ABSTRACT EXAMINATIONS. John Itakpe, DrPH, December, Public Health Analysis.

Transcription

1 ABSTRACT Title of Dissertation: ORAL CANCER IN MARYLAND: THE CORRELATION BETWEEN DENTIST KNOWLEDGE AND PRACTICES REGARDING ORAL CANCER EXAMINATIONS John Itakpe, DrPH, December, 206 Dissertation Chair: Dr. Farin Kamangar, MD, Ph.D. Public Health Analysis. Maryland was ranked 7 th among states with the highest oral cancer mortality rate in 996 (Siriphant, Horowitz, & Child, 200) and also had the highest disparity in oral cancer mortality rates for black males in all 50 states (Maybury, Horowitz, & Goodman, 202). Currently, Maryland ranks 27th in the incidence of oral cancer when compared to other states (Maybury et al., 202). This puts Maryland in the middle of the pack showing there is still a lot of work to be done to reduce the incidence of oral cancer. Horowitz, Drury, and Canto (2000) looked at the practices of Maryland dentists regarding oral cancer prevention and made some recommendations. These recommendations include continuing education for dental practitioners and a greater emphasis on oral cancer prevention and early detection in dental school curricula (Horowitz et al., 2000). This assumes that if dentists are knowledgeable about oral cancer, there will be a corresponding increase in the practices of oral cancer prevention and early detection. This research is a follow-up to the one done by Horowitz et al. (2000) to evaluate the effectiveness of Maryland dentist practices regarding oral cancer

2 prevention and early detection. The objective of this study is to look at the correlation between Maryland dentist knowledge and practices regarding oral cancer prevention and early detection. This is a mixed methods study where the researcher analyzed both quantitative and qualitative data. Responses from survey questionnaires that were distributed to Maryland dentists were analyzed using univariate, bivariate, and multivariate analyses. The qualitative aspect involved in-depth interviews regarding the progress made in reducing morbidity and mortality rates in Maryland from the late 990s until now. The purpose of this dissertation was to answer the question: will knowledge of oral cancer prevention and screening among dentists in Maryland who participated in the study have an association with their provision of oral cancer. Results showed that dentists who had a medium or high knowledge index score were more likely to practice oral cancer examinations 00% of the time compared to those with a low knowledge score.

3 ORAL CANCER IN MARYLAND: THE CORRELATION BETWEEN DENTIST KNOWLEDGE AND PRACTICES REGARDING ORAL CANCER EXAMINATIONS by John Itakpe A Dissertation Submitted in Partial Fulfillment of the Requirement for the Degree Doctor of Public Health MORGAN STATE UNIVERSITY December 206

4 ORAL CANCER IN MARYLAND: THE CORRELATION BETWEEN DENTIST KNOWLEDGE AND PRACTICES REGARDING ORAL CANCER EXAMINATIONS by John Itakpe has been approved October 206 DISSERTATION COMMITTEE APPROVAL:, Chair Farin Kamangar, MD, Ph.D. Alice Horowitz, Ph.D. Anne Marie O Keefe, JD, Ph.D. ii

5 Dedication I would like to thank God Almighty for His grace, wisdom, and strength that carried me throughout the course of this doctoral program. I dedicate this dissertation to my wife, Rosemary Azuka Itakpe, and to my children, Sharon, Anna and Bernice. Thanks for standing by me through this process that seemed unending. iii

6 Acknowledgements Several people were instrumental in several ways to seeing me through the course of my doctoral program. First, I would like to thank my dissertation committee comprised of the best minds in public health research. I am particularly grateful to my dissertation chair, Dr Farin Kamangar, for his encouragement and patience with me, to Dr. Alice Horowitz for believing in me and working with me through the process, and to Dr. O Keefe for her motivation throughout my doctoral program. To my mother, Rose Itakpe, you now have another doctoral degree to your record, and to my siblings, Joseph, Elizabeth, Peter, and Gloria, for your encouraging words. To the ladies in my life, Rosemary, Sharon, Anna, and Bernice, you mean the whole world to me. Rosemary, you always make sacrifices to accommodate me, you are a virtuous woman worth more than rubies. I love you dearly. To Alissa Leigh, Jummai Apata, Ndidi Adenuga, Eunice Ihotu, Bartholomew Omoba, Linda Kinney, Robinson Ohanador, and members of RCCG Mercy Court, thank you very much. Thank you Lord. iv

7 Table of Contents List of Abbreviations... viii List of Tables... ix List of Figures... x Chapter : Introduction... Background... Global statistics... 2 U.S. Statistics... 4 Maryland statistics... 6 The economic impact of oral cancer in Maryland... 8 Public health interventions to managing oral cancer... 9 Significance of Study... 0 Chapter 2: Literature Review... 2 Epidemiology... 4 Oral cancer etiology... 5 Tobacco... 6 Alcohol consumption... 7 Dietary factors... 8 Sexual activity and viral infection... 8 Exposure to sun... 9 Age... 9 Socioeconomic status... 9 Genetic predisposition v

8 Common Sites and Forms of Oral Cancer Demographics of Oral Cancer... 2 Survival and mortality rates... 2 Early Presentation of Oral Cancer Diagnosis of Oral Cancer Examination and detection of oral cancer Oral cancer screening through visual examination Early stage diagnosis General Medical and Dental Practitioners Updated Knowledge on Oral Cancer Training and Continuing Education Knowledge, Opinions, and Practices Regarding Oral Cancer Prevention Theory and Conceptual Model Research Question Chapter 3: Methodology Study Approval Research Design/Population and Sample - Quantitative Portion of Study Measurement of dependent variable Independent variables Statistical analysis Analytic Model Qualitative Portion of the Study... 4 Focus of inquiry... 4 vi

9 Interview data entry Qualitative data analysis of interviews Data Analysis Plan Chapter 4: Results Quantitative Results Qualitative Results Theme : The need for more education Theme 2: Importance of funding Theme 3: Importance of collaborations Theme 4: Importance of oral cancer prevention plan Theme 5: The importance of HPV and HPV vaccines in oral cancer prevention Theme 6: Importance of incentives in oral cancer screening Chapter 5: Discussion Strengths Limitations Recommendations References Appendices vii

10 List of Abbreviations ADA American Dental Association AMC American Cancer Society CDC Centers for Disease Control and Prevention DHMH Department of Health and Mental Hygiene HPV Human Papilloma Virus IARC International Agency for Research on Cancer MSDA Maryland State Dental Association NCI National Cancer Institute NDA National Dental Association NIDCR National Institute of Dental and Craniofacial Research SEER Surveillance, Epidemiology and End Results US United States WHO World Health Organization viii

11 List of Tables Table List of Qualitative Codes 43 Table 2 Demographics of Surveyed Maryland Dentists 46 Table 3 Logistic Regression of Performing Oral Cancer 49 Examinations at Initial Visit in Patients Age 8-39 by Demographic Data Table 4 Logistic Regression of Performing Oral Cancer 5 Examinations at Initial Visit in Patients Age 40 and Older by Demographic Data Table 5 Logistic Regression of Performing Oral Cancer 54 Examinations at Recall Visits in Patients Age 8-39 by Demographic Data Table 6 Logistic Regression of Performing Oral Cancer 56 Examinations at Recall Visits in Patients Age 40 and Older by Demographic Data ix

12 List of Figures Figure. Age standardized ratio, mortality, and incidence rates for oral 3 cancer by population and gender for the world (International Agency for Research on Cancer, 205). Figure 2. Cumulative risk for developing oral cancer by population 4 (International Agency for Research on Cancer, 205). Figure 3. Incidence and mortality rates for oral and other cancers by 6 population for different cancers within the United States (International Agency for Research on Cancer, 205). Figure 4. Oral cancer incidence and mortality rates by gender and race 7 comparing Maryland with the United States in 20. Figure 5. Percentage of Maryland adults who had oral cancer 8 examinations in the past 2 months between 2002 and 202 (Maryland Department of Health and Mental Hygiene, 203). Figure 6. Conceptual model. 37 Figure 7. Analytical model. 4 Figure 8. Mixed methods explanatory research design 44 Figure 9. Stata output of correlation between dentists practices and knowledge index. 58 Figure 0. Scatterplots for correlations of oral cancer examinations at 59 initial and recall visits with dentist knowledge score. x

13 Chapter : Introduction Background Oral cancers are a group of tumors found in and around the oral cavity, lip, tongue, palate (soft and hard), pharynx, tonsils, salivary glands, and other less frequent areas around the oral region (Applebaum, Ruhlen, Kronenberg, Hayes, & Peters, 2009; Greenlee, Hill-Harmon, Murray, & Thun, 200). There are predisposing contributory factors to developing oral cancers, and globally tobacco and alcohol are regarded as the major factors for these cancers (Krüger et al., 204; Petersen, 2009). Other factors include oral health conditions, diet, exposure to sunlight and more recently, the association with Human Papillomavirus (HPV; Kreimer, Clifford, Boyle, & Franceschi, 2005). Persons who are older than age 40, who smoke heavily, and also consume alcohol are at the highest risk for developing oral cancers (Cruz et al., 2002). It is imperative, therefore, to say that when smoking and alcohol consumption are stopped or controlled, it will impact the incidence of oral cancer and subsequently lead to the reduction of the global burden of the disease. In 2003, the International Agency for Research on Cancer (IARC) determined that consumption of smokeless tobacco is one of the causes of oral cancer (Petersen, 2009). It also has been noted that increases in oropharyngeal cancers lately in the United States has been attributed to HPV (Chaturvedi et al., 20). Preventive programs such as tobacco cessation education and increasing taxes on the respective products can go a long way to reduce the incidence of oral cancers. The increase of taxes on tobacco products has shown the greatest progress of all interventions to reduce the use of tobacco products (Chaloupka, Yurekli, & Fong, 202).

14 Global statistics. The IARC runs the Globocan project. The aim of the project is to provide contemporary estimates of the incidence of mortality and prevalence from major types of cancer, at national level, for 84 countries of the world (International Agency for Research on Cancer, n.d.). The IARC is an arm of the World Health Organization (WHO). Epidemiological data on oral cancer incidence and mortality are stored in the Global Oral Health Data Bank (Petersen, 2009). These data are shared within and between countries to build capacity in oral cancer prevention. It is estimated that more than 20 million people in the world live with a diagnosis of cancer, and about half of these people live in developing countries (Petersen, 2009). Figure shows incidence and mortality age standardized ratio for oral cancer around the world with Melanesia a region consisting of four countries, namely Vanuatu, Solomon Islands, Fiji, and Papua New Guinea having the highest incidence and mortality rates. This is also clearly depicted in Figure 2 showing the cumulative risk of developing oral cancer in ages

15 Figure. Age standardized ratio, mortality, and incidence rates for oral cancer by population and gender for the world (International Agency for Research on Cancer, 205). 3

16 Figure 2. Cumulative risk for developing oral cancer by population (International Agency for Research on Cancer, 205). U.S. statistics. According to the National Cancer Institute (NCI), the age adjusted incidence rate for oral cancer and oropharyngeal cancers is per 00,000 persons per year, with an age adjusted mortality rate of 2.5 per 00,000 persons per year based on data collected between 2008 and 202. The International Agency for Research on Cancer 4

17 (205) list of cancers by population in the U.S. is shown in Figure 3. The American Cancer Society estimates that about 39,500 people are diagnosed with oral or oropharyngeal cancers in the U.S., and about 7,500 persons will die from oral cancers in a year. There had been a decrease in the incidence of oral cancer in the U.S., but the advent of the Human Papillomavirus (HPV), which is associated with oropharyngeal cancers, has increased its incidence especially in white men and women (Simard, Ward, Siegel, & Jemal, 202). The advent of HPV-associated oral cancers also led to a decrease in the average age incidence of oral cancers (Jacobson et al., 202). 5

18 Figure 3. Incidence and mortality rates for oral and other cancers by population for different cancers within the United States (International Agency for Research on Cancer, 205). Maryland statistics. In 20, the Maryland age adjusted incidence (0.2/00,000 population, 95% CI [9.4-.0]) for oral cancer was similar to that of the U.S. Surveillance, Epidemiology and End Results (SEER) (.0/00,000 per population, 95% CI [0.8-.2]), while the oral cancer age adjusted mortality rate was 2.4/00,000 population (95% CI [ ]) (Maryland Department of Health and Mental Hygiene, 204). This can be seen in Figure 4. From data collected between 2006 to 200, 6

19 Maryland was ranked 27 th in the oral cancer mortality rate compared to other states and Washington D.C. Oral Cancer Incidence and Mortality Rates by Gender and Race, Maryland and the United States, 20 Incidence 20 Total Males Females Whites Blacks A/PI New Cases (count) MD Incidence Rate U.S. SEER Rate Mortality 20 Total Males Females Whites Blacks A/PI Deaths (count) MD Mortality Rate U.S. Mortality Rate ** N/A Rates are per 00,000 population and are age-adjusted o 2000 US. Standard population Total also includes cases reported as transsexual, hermaphrodite, unknown gender, and unknown race ** MD mortality rates based on death counts of 0-9 are suppressed per DHMH/Center for Cancer Prevention and Control Mortality Data Suppression Policy Source: Maryland Cancer Registry U.S. SEER, SEER*Stat Maryland Vital Statistics Administration U.S. SEER, Cancer Statistics Review Figure 4. Oral cancer incidence and mortality rates by gender and race comparing Maryland with the United States in 20. Figure 5. Maryland has consistently fallen short of its objectives which can be seen in 7

20 Maryland *Adults age 40 years and older Note: Graphic includes results from both the Maryland BRFSS and Maryland Cancer Survey. See Appendix A, Section G for a cautionary note on comparing these data. Source: Maryland Cancer Survey, 2002, 2004, 2006, and 2008 Maryland BRFSS, 200 Maryland Comprehensive Cancer Control Plan Figure 5. Percentage of Maryland adults who had oral cancer examinations in the past 2 months between 2002 and 202 (Maryland Department of Health and Mental Hygiene, 203). The economic impact of oral cancer in Maryland. Oral cancers contribute globally to the burden of disease caused by all cancers. Cancer is an expensive disease to manage; prevention is the most cost effective way to deal with the disease (Petersen, 2009). The cost of managing oral cancer patients is enormous due to the high morbidity it has on the patients. Some of the patients will not be able to go back to work after treatment. The management of cancers contributes significantly to the cost of health care in the U.S. (Jacobson et al., 202). Jacobson et al. (202) commented on the fact that 8

21 head and neck cancers are of particular interest because they are extremely expensive to treat, have a high morbidity, and of those individuals that survive only 48% return to work (p. ). Jacobson et al. (202) has suggested that the treatment of oral cancers may be the highest of all cancers in the U.S., and the cost of burden is not just on the patient but on the employer as well. The cost burden of oral cancer takes a toll on the health care systems themselves including the insurance companies, Medicare, and Medicaid (Jacobson et al., 202). Due to the high mortality rate of oral cancer, especially when it is found at the later stages III and IV, screening and early diagnosis is very important (van der Waal, 203). Public health interventions for managing oral cancer. The major predisposing factors to oral cancer include tobacco, alcohol consumption, diet, HPV infection, exposure to sunlight, age, and genetic predisposition. Oral cancer can be prevented when we intervene with the risk factors (Petersen, 2009). Some oral cancers can be prevented while others can be treated if detected early. The aim of cancer prevention is to reduce as much as possible new cases and deaths that are attributed to oral cancer and also to ensure that those who had oral cancer can lead normal lives with little debilitating effects. Tobacco cessation programs and programs to reduce alcohol consumption are the major interventions to reduce oral cancer incidence and mortality. Increases in taxes of tobacco and tobacco products have been shown to be a very effective tool in reducing tobacco consumption which ultimately leads to a reduction in oral cancer (Chaloupka et al., 202). 9

22 Another important public health intervention in managing oral cancer is the legislation against smoking in public places. This has led to the prevention of nonsmokers from second hand smoke and its consequences and has also encouraged people to quit smoking or to reducing the number of cigarettes they smoke (Fichtenberg & Glantz, 2002). Protective safe oral sex practices also are important public health interventions especially as they relate to HPV-associated oral cancers. It is interesting to note that younger adults with no typical behavior of smoking or consuming alcohol are now increasingly being diagnosed with oral cancer (Martín Hernán, Sánchez Hernández, Cano Sánchez, Campo, & Romero, 203). Protective safe oral sex practices is one approach to prevent people from contracting HPV, which is implicated in the increasing number of oral cancers that are currently seen. Significance of the Study Oral cancers are among the most debilitating and disfiguring malignancies in the United States, and they are the sixth most common cancers worldwide (Horowitz, Canto, & Child, 2002). The incidence of oral cancers increases with age, especially after age 40, and there is a gender disparity with men more predisposed to it than women. Overall, the National Institute of Dental and Craniofacial Research (206) estimates the five year survival rate for oral cancer as 75% when diagnosed early, but only 25% when diagnosed at later stages. Oral cancer staging is important in the prognosis of the disease and a good predictor of survival (Cleveland & Thornton-Evans, 2009). On average, only about 60% of people diagnosed with oral cancer will survive more than five years. When oral cancer is diagnosed early, it is more likely that such persons will survive longer (Cleveland & 0

23 Thornton-Evans, 2009). This makes it very important for dental professionals who are the main custodian of the oral cavity to screen early for oral cancers. In Maryland, previous reports have shown that incidence and mortality rates from oral cancer were higher than the national average, however, they are decreasing. There has been some reduction in age adjusted oral cancer mortality rates (2.5/00,000 population, 95% CI [2.-2.9]) which are now similar to what is reported for the United States as a whole (2.4/00,000 population, 95% CI [ ]) (Vargas, Casper, Altema- Johnson, & Kolasny, 202). Interventions like tobacco cessation programs, reduction in chronic alcohol consumption, and early screening can reduce mortality rates from oral cancer (Jemal, Center, DeSantis, & Ward, 200). With the advent of the Human Papillomavirus (HPV), the incidence of oral cancer, which was on the decline, began to increase. The Centers for Disease Control and Prevention (202) has reported that about 72% of oral cancers are HPV-related. Dentists attitudes and knowledge in Maryland regarding oral cancer prevention have been published by Maybury et al. (202). This study found gaps in dentist knowledge and attitudes regarding oral cancer prevention. According to the authors, less than one third of dentists surveyed knew that oral cancers were more common in people older than age 60. In Maryland, there has been a lot of research showing the attitudes and knowledge of dentists, but there has been no publication written about the practices of dentists since the Yellowitz et al. (995) study. This current research will highlight the current practices of Maryland dentists and the impact on oral cancer reduction.

24 Chapter 2: Literature Review Oral cancer refers to all aggressive neoplasms that affect the external lip and oral cavity oropharynx, but oral squamous cell carcinoma (OSCC) can affect all tissues of epithelial origin (Barnes, Eveson, Reichart, & Sidransky, 2005). Cancer over the years has turned out to be a major public health issue in both developed and developing countries (Peterson, 2003). According to Ferlay, Bray, Pisani, and Parkin (2000), the World Health Organization (WHO) has identified oral cancer as one of the cancers with the highest mortality ratio among major malignancies. Oral cancer is also ranked as the eighth most common cancer in the world (Petersen, Bourgeois, Ogawa, Estupinan-Day, & Ndiaye, 2005; Stewart & Kleihues, 2003). Many countries have reported the incidence rate of oral cancer to be between -0 cases per 00,000 population of males (Petersen, 2009). Furthermore, the highest rate of oral cancer cases have been found in Melanesia, south central Asia, and central and eastern Europe; the lowest rate of cases have been reported in eastern Asia, Central America, and Africa in male and female populations. Oral cancer accounts for -40% of major malignancies in the United Kingdom (Johnson & Warnakulasuriya, 993). The incidence rate was pegged at 3,500 cases per year in the UK (McCann, Macpherson, & Gibson, 2000). The highest incidence rate was recorded in France with approximately 5,500 cases annually (Warnakulasuriya, 200). In south central Asia, oral cancer was ranked as one of the most common types of cancer. Data obtained from Africa proves difficult to be used in estimating the true incidence rate because they are limited to a few hospital registries (Warnakulasuriya, 2008). In Sudan, oral cancer is the fifth most common type of cancer with an estimated 2

25 incidence rate of 920 per year (IARC, 200). In men, a high mortality rate was recorded, and this may be due to the snuff-using style in men from that region (Idris, Ahmed, Mukhtar, Gadir, & El-Beshir, 995). Globally over 90% of oral cancers are oral squamous cell carcinoma. This malignancy has a very high ability to gradually metastasize to regional lymph nodes and is more prevalent in individuals that are over age 40 (Barnes et al., 2005; Warnakulasuriya, 2009). The tumor stage is the most important prognostic marker of oral cancer, as such there is need for early detection at the premalignant or potentially malignant stage to reduce morbidity and mortality (Lingen, 2008; McCullough, Prasad, & Farah, 200). Oral potentially malignant lesions (OPML) is a collective term used for a wide range of clinical presentations of oral lesions that may harbor oral epithelial dysplasia (OED). OPMLs may appear as leukoplakia, erythroplakia, or erythro-leukoplakia (Brocklehurst, Baker, & Speight, 200). The clinical presentation of these lesions is the major factor deciding whether to do a biopsy or other interventions (Dost, Le Cao, Ford, & Farah, 203). The most common OPMLs are the leukoplakias, and they have a low rate of malignant progression (4-8%). When diagnosing OPMLs histopathologically, they may be classified as mild, moderate, or severe dysplasia (Tsantoulis, Kastrinakis, Tourvas, Laskaris, & Gorgoulis, 2007). WHO classifies OED into mild, moderate, and severe dysplasia which is also known as carcinoma insitu (Barnes et al., 2005). Notwithstanding advances in technology and treatment, there has been just a little improvement in the five-year survival rate of patients diagnosed with oral cancer over the 3

26 past ten years (Downer, Moles, Palmer, & Speight, 2006). The major reason associated with poor prognosis according to Lingen (2007) is late diagnosis. When oral cancer is detected at the early stage, the survival rate is 83% in the United States; if detected after it has metastasized distantly it is only 28% (Lingen, 2007). This research is poised to address the issue. Although the oral cavity can be accessed easily, about 67% of oral cancers in the United States are diagnosed after the disease has metastasized regionally or distantly (Lingen, 2007). Epidemiology The knowledge, attitudes, and practices for oral cancer among dentists have been investigated, and many epidemiological results have been published. The essence of these studies is to understand the knowledge, attitudes, and practices of dental health care providers to determine if educational interventions are needed to increase their effectiveness in the prevention and early detection of oral cancer and their capacity to help reduce the associated morbidity and mortality rates (Horowitz, Drury, Goodman, & Yellowitz, 2000). Opinions and practices regarding oral cancer prevention and early detection have been described in numerous surveys with variable results. Various studies have been done to assess the knowledge of dentists. A few of these studies have been done in the United States including Maryland, Texas, and New York (Alonge & Narendran, 2003; Horowitz et al., 2000; Gajendra, Cruz, & Kumar, 2006; Yellowitz, Horowitz, Drury, & Goodman, 2000 ). Studies have also been done in the UK, Brazil, Canada, Ireland, Spain, and Italy (Clovis, Horowitz, & Poel, 2002; Colella, Gaeta, Moscariello, & Angelillo, 2008; Decuseara, MacCarthy, & Menezes, 20; Kujan, Duxbury, Glenny, Thakker, & Sloan, 2006; Leão, Góes, Sobrinho, & 4

27 Porter, 2005; López-Jornet, Camacho-Alonso, & Molina-Miñano, 200). The results of these studies showed that dentists were generally knowledgeable about oral cancer, but at there were gaps in their knowledge about oral cancer. They further went on to report that sufficient preventive activities that could help patients were not provided. Responses obtained from these studies varied greatly. Warnakulasuriya and Johnson (999), in a study among dentists in the UK, obtained a weak response rate of 6% when they analyzed data from 2,532 questionnaires. Decuseara and colleagues (20) in Ireland obtained an 8% response rate, while in Italy a 45.7% response rate was obtained by Colella and colleagues (2008). Kujan et al. (2006) obtained a better response rate of 66.9%. In New York, a random sample of practicing dentists was surveyed and it was found that these professionals were knowledgeable but had gaps in knowledge related to the risk factors and oral cancer examination techniques (Gajendra et al., 2006). Leão, Góes, Sobrinho, and Porter (2005) observed that knowledge of oral cancer among Brazilian dentists was suboptimal, while a comparable study in Ireland suggested that Irish dentists were generally knowledgeable of oral cancer risk factors and diagnostic concepts (Decuseara et al., 20). Oral cancer etiology. Oral cancer is not caused by any single factor, rather it emanates from a combination of extrinsic and intrinsic factors which after a period of time may lead to oral cancer (Warnakulasuriya, 200). Also each individual s unique response to both known and unknown risk factors may lead to development of oral cancer (Petersen, 2009). Tobacco, alcohol use, and poor diet are modifiable risk factors (Petersen et al., 2005). Other risk factors may include age, immunosuppression, and 5

28 previous history of oral cancer. The frequency of HPV-associated oral cancer has been on the rise and therefore HPV status of a patient will have a significant effect on the prognosis of oral cancer (Westra, 2009). The most common HPV serotype associated with oral cancers is HPV 6 (Herrero et al., 2003). Tobacco. The most significant risk factor of cancer is tobacco, and it is available in both smoked and smokeless form. The addictive element of tobacco is nicotine, while the carcinogens are in the tar. Discontinuation of tobacco use is the most valuable form of primary prevention (Patton, Ashe, Elter, Southerland, & Strauss, 2006). According to Davenport et al. (2003), the risk of oral cancer is correlated with the time tobacco has been used. The risk of oral cancer and premalignant lesions increased with the amount of tobacco consumed and the number of years a smoker has been on alcohol. In a study by Speight et al. (2006), a relative risk of 3.43 was found when smokers were compared to nonsmokers. They further reported that patients who continued to smoke after an oral cancer diagnosis were at a greater risk for a second oral cancer. The World Health Organization (2003) reported that 4.4 million people died as result of nicotine addiction. This very large number of deaths is rising rapidly, particularly in low and middle income countries where half of all deaths are attributed to tobacco use (Guilbert, 2003). This proportion was projected to rise by 2005 worldwide (World Health Organization, 2003), and 42% of deaths recorded from oral cancer are as a result of tobacco smoking (Danaei, Vander Hoorn, Lopez, Murray, & Ezzati, 2005). A recent study estimated that in the United Kingdom, about 70% of oral and pharyngeal cancers occur in men and about 30% occur in women, and in most cases the oral cancers were caused by tobacco smoking (Warnakulasuriya, 2009). 6

29 Tobacco is used in several ways; it can be smoked, chewed alone, or added to betel quid. The IARC has confirmed the evidence that smokeless tobacco also causes oral cancer (Cogliano et al., 2004; Reibel, 2003) and confirmed that the risk was both dose and time dependent. There is a strong association between oral cancer and tobacco use ( Johnson, 200). Although smokeless tobacco use increases the risk of developing oral cancer by up to four times, smoking tobacco is far worse (Johnson, 200). The risk of developing oral cancer increases from three to seventeen times in smokers compared to non-smokers (Neville & Day, 2002). Data obtained by Lubin et al. (200) suggests that a lifetime dosage relationship exists. Smokers with less than 30 pack years show an odds ratio of 2.9 compared to those with greater than 40 pack years with an odds ratio of 0. (Lubin et al., 200). Alcohol consumption. Heavy use of alcohol is also a major risk factor for oral cancer and is often cited as such (Altieri et al., 2004). Studies done by Andre, Schraub, Mercier, and Bontemps (995) and Lewin et al. (998) show that heavy alcohol consumption increases the risk of developing oral cancer from three to nine times. Alcohol has a dose dependent response relationship to oral cancer. Risk of oral cancer increases both with the duration of alcohol consumption and amount consumed. The mechanism by which alcohol acts as a carcinogen is not known, but some theories include the presence of actetylaldehyde, a known carcinogen and metabolite of alcohol and ethanol which causes DNA damage, nutritional deficiencies associated with heavy drinking and also the carcinogen effect of chemicals other than ethanol in alcohol beverages (Yellowitz et al., 2000). 7

30 Dietary factors. Diet plays a crucial role as a protective factor against the development of oral cancer (World Health Organization, 2003). According to Schatzkin and Kipnis (2004), 30% of cancers in Western countries are as a result of dietary factors. Diets low in vitamins A, C, and E have been associated with increased risk of oral cancer development (McLaughlin et al., 988). In 2006, a study identified evidence that vegetables and fruits, particularly citrus fruits, protect against oral cancer development. The study showed a significant risk reduction of above 50% for each additional daily serving of fruits or vegetables (Pavia, Pileggi, Nobile, & Angelillo, 2006). According to Sanchez et al. (2003), an individual who consumes a diet low in fruits and vegetables is at an increased risk for oral cancer. They further reported that a combination of poor nutrition with tobacco and alcohol use accounts for about 85% of oral cancers. Pavia et al. (2006) recommended the daily allowance of fruits and vegetables to reduce the risk of oral cancer by 50%. They suggested that citrus fruits and orange and yellow vegetables should be consumed daily since they have been found to be particularly protective. Sexual activity and viral infection. According to Gillison (2007), infectious agents have been implicated in some cancers of the oral cavity and pharynx. Recent studies have implicated the Human Papilloma Virus (HPV) and suggest that about 35% of all oral cancers are positive for HPV DNA (Kreimer et al., 2005). HPV is a large group of viruses that are responsible for a variety of oral and skin pathology including warts, papilloma, and cancers of the cervix. HPV is classified into low and high risk subtypes. The high risk subtypes are associated with cancer when they 8

31 turn the cells in that area to become abnormal. Oral health professionals should be aware of the role HPV plays in the etiology of oral cancer and how the virus is transferred. This is important so as not to ignore clinical lesions in patients who do not have other more obvious risk factors. Heck et al. (200) reported an association between oral cancer and sexual activity. They observed that women who had indulged in oral sex had four times the risk of developing oral cancer of the base of the tongue compared to women who do not. Exposure to sun. Exposure to sunlight can put people at increased risk of developing skin cancer. When people are outdoors for an extended period of time, there is increased risk of developing lip cancer (Johnson, 200). A high incidence of lip cancer has been reported among Caucasians compared to blacks and it is higher in Caucasian males than females (Canto & Devesa, 2002). The use of photoprotective lip blocks, i.e..lip products that contain sunscreen, are helpful in the prevention of lip cancer Age. In Europe, 98% of all head and neck cancers were seen in patients over 40 years of age. This shows that increasing age was a significant risk factor in developing oral cancer (Shedd & Gaeta, 97). Oral cancers are seen an earlier age in HPVassociated oral cancers (Chaturvedi, Engels, Anderson, & Gillison, 2008) Socioeconomic status. Conway et al. (2008) observed that low socioeconomic status is significantly associated with an increased oral cancer risk. This group is likely to have low levels of health literacy. They lack empowerment due to less access to health services and health education and they likely have fewer fact finding skills. These shortcomings make them less capable of making knowledgeable decisions to protect and improve their own health (Petersen, 2009). 9

32 Genetic predisposition. Until recently the etiology of oral cancer has been examined in terms of environmental factors, but recently the possible role of genetic factors that predispose persons to this condition have been brought to light. An individual with a hereditary predisposition to this condition has an increased likelihood of developing oral cancer in the long run (Negri et al., 2009). Individuals who have homozygous deletion of the Glutathione S-transferase Mu (GSTM ) gene have increased risk of oral cancer. The risk increases further when these individuals are exposed to environmental toxins such as chemicals in cigarette smoke, alcohol, and betel quid (Kietthubthew, Sriplung, & Au, 200). Copper et al. (995) reported that there was an increased risk of cancer among relatives of patients with squamous cell carcinoma. Common Sites and Forms of Oral Cancer According to Kujan et al. (2006), 90% of the cancers that affect the oral cavity are oral squamous cell carcinoma (OSCC) arising from the oral mucosal lining. This is closely followed by adenocarcinomas and Kaposi sarcomas. Oral cancers may appear on any mucosal site. They usually occur in a U-shaped zone from the tonsillar pillars and lateral margins of the soft palate, laterally on the tongue, floor of mouth and ending at the anterior part of the mouth (Neville & Day, 2002). Warnakulasuriya (2009) reported that the tongue was the most common anatomical site of oral cancer. The incident rates of oral squamous cell carcinomas according to Sapp, Eversole, and George (2004) are the tongue (25%), lower lip (30-40%), floor of mouth (20%), and oropharynx and soft palate (5%). Tobacco and alcohol related lesions are located in different areas of the oral cavity, as are lesions from HPV. HPV-related lesions appear 20

33 towards the posterior regions of the oral cavity, while lesions related to alcohol and tobacco use appear more often on the anterior aspect of the tongue, floor of the mouth, buccal mucosa, and alveolar ridges (Oral Cancer Foundation, 2008). In a study conducted by Lopez-Jornet, Camacho-Alonso, and Molina-Miñano (20) in Spain, 90.6% of dentists correctly identified OSCC as the most frequent histological type of oral cancer. Colella et al. (2008) in their study reported that only 32% of Italian dentists identified this fact. Eighty nine percent (89%) of Spanish dentists and 59.5% of Italian dentists were aware that the tongue and floor of the mouth were the two most common sites of oral cancer. Yellowitz et al. (2000) reported similar findings among practicing dentists in the United States. Applebaum et al. (2009) carried out a survey in Massachusetts in which they sampled dentists and primary care physicians. Only 9% of physicians and 39% of dentists identified the two most common sites of oral cancer. Demographics of Oral Cancer Recently there has been an increase in the number of young adults developing oral cancer. Previously it had usually occurred in middle aged and older people (Llewellyn, Johnson, & Warnakulasuriya, 200). Canto, Drury, and Horowitz (200) report in their study that only 35% of dentists surveyed reported that the majority of oral cancer was diagnosed in patients age 60 or older. Vijay, Kumar, and Suresan (202) reported that the high risk age groups for oral cancer were in their 40s, 50s, and older than 60s. Survival and mortality rates. Silveira et al. (2007) reported that the mortality rate of oral cancer was strongly correlated with the stage of the diagnosis. They observed 2

34 that early detection and low staged lesions were associated with significantly improved survival. In most cases, diagnosis of oral cancer is in stages 3 and 4 with lymph node metastasis (Silverman & Gorsky, 990). Although great advances in chemotherapy, radiation, and surgery have been made, the five year survival rate of oral cancer has not improved significantly (Neville & Day, 2002). Early Presentation of Oral Cancer The term oral potentially malignant disorders (OPMD) was recommended in 2005 by an international working group convened by the WHO Collaborating Center for Oral Cancer and Precancer in London (Warnakulasuriya, Johnson, & van der Waal, 2007). This term was coined because many oral cancers appear in the oral mucosa but some may be preceded by pre-existing oral diseases such as leukoplakia, erythroplakia, Lichen Planus, and submucosal fibrosis. People with OPMD have an increased risk of progressing to malignancy (Ho et al., 2009; Reibel, 2003) Reibel (2003) also noted that the transformation of OPML lesions to malignancy varies according to site, gender, duration, and population. It is also noted that when the lesions occur in the floor of the mouth and lateral border of the tongue, a higher risk of malignancy is expected (Napier & Speight, 2008). Diagnosis of Oral Cancer Pathologic assessment and tissue biopsy by trained health care providers remains the gold standard for oral cancer diagnosis. This technique is invasive, sometimes painful, time consuming, and very expensive. Another procedure which is useful is called exfoliative cytology which involves removal of cells with a cytology brush. This 22

35 procedure was reported by Pektas, Keskin, Gunhan, and Karslioglu (2006) to be highly sensitive and specific. Applebaum et al. (2009) surveyed dentists and physicians, and among the dentists sampled 57% of them correctly identified the most common symptoms of early oral cancer while 24% of physicians correctly identified these symptoms. They further reported that 34% of dentists and 0% of physicians could identify erythroplakia and leukoplakia as the two most likely conditions to be associated with oral cancer. Two thirds of New York dentists correctly identified that enlarged lymph nodes are usually hard, painless, and either mobile or fixed. Leukoplakia and erythroplakia were identified by 95% of Spanish dentists as mucosal lesions mostly associated with oral cancer (Lopez-Jornet et al., 20). Colella et al. (2008) reported that Italian dentists showed significant gaps in knowledge with respect to diagnostic procedures; only one third of them could correctly identify oral cancer lesions. Examination and detection of oral cancer. The primary method for detecting oral cancer is a comprehensive clinical examination; this examination usually includes physical examination and a thorough history (Sciubba, 200). The history usually covers the medical history and social history considering risk behavior such as tobacco and alcohol use. Horowitz, Siriphant, Sheikh, and Child (2000) noted that the risk determination is important for oral cancer and the need for tobacco cessation counseling. Horowitz et al. (200) also noted physical examination involves digital palpation of neck nodes regions, bimanual palpation of the floor of mouth, and observation of oral pharyngeal mucosa with good light and mouth mirror. This examination takes less than 90 seconds to perform. Smith, Cokkinides, and Eyre, 2007 reported that the American 23

36 Cancer Society recommends oral cancer examinations for people older than age 40 every year. The majority of Spanish dentists (89.7%) suggested that oral cancer examinations should be provided annually for patients aged 40 and older (Lopez-Jornet et al., 20). In Texas, 86% of dentists agreed that they conducted such routine oral cancer examinations, 83% of Maryland dentists agreed that they conducted routine examinations, and 92% of dental specialists in the UK carried out such routine examinations (Dodds et al., 994; Yellowitz & Goodman, 995). In 2004, Le Hew and Kaste reported that 92.3% of dentists performed oral examinations on asymptomatic patients, and 40.6% said they do so at least annually. Cruz, Ostroff, Kumar, and Gajendra (2005) reported that 86% of dentists in New York carried out routine oral cancer examinations. Oral cancer screening through visual examination. When patients present themselves for regular dental checkups it is recommended that an oral cancer screening test should be performed as a proactive measure that may result in reduced morbidity and mortality (Warnakulasuriya & Johnson, 996). The sites involved in oral cancer are easily visible with the exception of the base of the tongue and accessible to dental caregivers and do not require specialized equipment and techniques (Petersen, 2008). Kujan et al. (2006) observed that 95% of UK dentists used a visual examination for oral cancer screening because it is simple, acceptable, inexpensive, and highly specific. Early stage diagnosis. Early detection of oral cancer can suggest either a short time interval of oral cancer development or a small tumor at the time of diagnosis (van 24

37 der Waal, de Bree, Brakenhoff, & Coebergh, 20). The aim of early detection is to diagnose oral cancer at a very early stage. To achieve this, the tumor should be small, less that 2cm in diameter and 4mm in invasion depth, and the patient should be asymptomatic (Woolgar, 2006). In addition to the challenge of detecting and diagnosing oral cancer at an early stage, it is important to note that diagnostic delay is also a determinant factor in oral cancer survival (Brocklehurst et al., 203). Diagnostic delay refers to the total time that elapses from the time a patient first becomes aware of symptoms until a definitive diagnosis is made by a professional (Seoane-Leston et al., 200). Psychosocial issues such as perceptions of symptoms and illness, behavioral responses, accessibility to health care including financial barriers, and structural and personal barriers such as beliefs, culture, and language are causes of patient delay (Seoane-Leston et al., 200). Causes of professional delay provide an opportunity for interventions, which may lead to increases in opportunistic screening of high-risk populations. Studies have shown that lack of knowledge on the part of health providers regarding the main locations of oral cancer, low suspicion of oral cancer, and low levels of skill and confidence to perform a full head and neck examination with appropriate equipment are prevalent in the general medical and dental communities (Alonge & Narendran, 2003). Studies done by Sandoval et al. (2009) and Kantola, Jokinen, Hyrynkangas, Mantyselka, and Alho (200) showed a strong relationship between professional delay and decreased survival rates. 25

38 General Medical and Dental Practitioners To achieve early stage at diagnosis, patients must be diagnosed in the asymptomatic phase. This requires health practitioners to perform oral cancer screening examinations (Horowitz & Alfano, 200). In December 2000, the United Kingdom introduced an oral cancer awareness week and also attempted to reduce professional delay (Hobson, Malla, Sinha, Kay, & Ramamurthy, 2008). When oral cancer awareness among general medical practitioners (GMP) and general dental practitioners (GDP) was accessed in a study, there was divergence in most of the populations studied. Carter and Ogden (2007) conducted a study in the UK and found that GMPs were less likely to examine patients oral mucosa routinely. They were less likely to advise patients about risk factors for oral cancer screening. They also identified fewer risk factors for oral cancer and felt less confident about diagnosing it from clinical appearance than general dental practitioners. A study of 640 dental practitioners in Australia showed that over 90% were in the habit of regularly performing oral mucosa screening examinations for all patients (Allen & Farah, 205). They reported that Australian dentists lack training, confidence, time, and financial incentives as barriers to performing mucosal screening. Updated Knowledge of Oral Cancer It is recommended that continuous updating of oral cancer knowledge and understanding through post-graduate programs is important to enhance professionals knowledge of oral cancer risk factors and diagnostic concepts. Some studies carried out in the United States among dentists showed that 72% of New York dentists agreed that their knowledge was up-to-date (Gajendra et al., 2006). Yellowitz, Horowitz, Goodman, 26

39 Canto, and Farooq (998) also reported that three-fourths of U.S. dentists strongly agreed or agreed that their knowledge of oral cancer is current. British Columbia and Nova Scotia dentists were assessed, and 56.7% of them agreed that their knowledge of oral cancer was current (Clovis et al., 2002). Applebaum et al. (2009) reported that 50% of dentists in Massachusetts agreed or strongly agreed that their knowledge about oral cancer was up-to-date. Training and Continuing Education There is no uniformity in the training of dentists to diagnose early cancerous lesions, leaving a large number of dentists inadequately trained (Yellowitz, Horowitz, Goodman, Canto, & Farooq, 998). In the UK, Kujan et al. (2006) reported that 50% of dentists described their training in providing oral cancer examinations as sufficient while 88% of U.S. general dentists strongly agreed or agreed that their training on screening was adequate (Yellowitz et al., 998). Studies also have shown that dentists and other health care workers need systematic educational updates in oral cancer prevention and early detection (Horowitz et al., 2000). LeHew and Katse (2007) reported that most dentists attend continuing education (CE) programs on oral cancer early detection. This suggests that many perceive a need to update their knowledge and early detection skills. Clovis et al. (2002) observed that dentists who attended an educational course in the preceding year on oral cancer were more likely to have a higher level of knowledge about oral cancer. Changes in knowledge and perceived competency due to diagnosis of oral and pharyngeal cancer after a multi-component educational intervention targeted at health care professionals was reported by Barker, Williams, McCunniff, and Barker (200). 27

40 Parrott, Godfrey, Raw, West, and McNeill (998) showed in their study that a 0-minute quit smoking consultation by a health professional can assist 3% more smokers to abstain from smoking for six months or longer compared to those who received no advice. The United States Preventive Services Task Force recommends that appropriate counseling should be provided to those persons who smoke, chew tobacco, or use snuff. Early identification of high-risk patients with oral cancer and speedy referral to a specialist for treatment are an important part of primary dental care (Sciubba, 200). Knowledge, Opinions, and Practices Regarding Oral Cancer Prevention Horowitz et al. (2000) reported that primary prevention of oral cancers included reducing risk factors such as tobacco, alcohol, exposure to sunlight, and others. They also reported that increased consumption of fruits and vegetables is a protective measure. They hypothesized that detection of lesions in the early stage would reduce morbidity and mortality. In their study, they sampled dentists in Maryland with the aim to determine their knowledge of oral cancer risks, determine knowledge of diagnostic procedures, and describe any relationship between dentist background characteristics and their knowledge of oral cancer. They administered a pretested 34-item questionnaire to a simple random sample of 800 general practice Maryland dentists. They obtained a total of 508 useable questionnaires. Knowledge of oral cancer was assessed from 4 questions, nine questions were on oral cancer diagnostic procedures, and some items described selected aspects of the respondents background. From the results they obtained, virtually all respondents identified use of tobacco as a risk factor, and about 95% correctly identified a prior oral cancer lesion and use of 28

41 alcohol as risk factors. In contrast, only 68% identified older age as a risk factor, and about 35% indicated that the majority of oral cancers are diagnosed at age 60 and older. One third of the participants recognized the protective effect of consuming fruits and vegetables. When knowledge of the diagnostic procedure was accessed, 80% of the respondents reportedly knew how to examine the tongue and surrounding areas for signs of oral cancer, 80% knew that the most common type of oral cancer is squamous cell carcinoma and that early oral cancer lesions are small and painless, and 70% knew that a patient is asymptomatic when he or she has an early oral cancer lesion and that the ventral lateral border of the tongue is the most common area for oral cancer. Fifty percent (50%) knew that oral cancer lesions are diagnosed in advanced stages, and 32% identified erythroplakia and leukoplakia as the two most common conditions associated with oral cancer. Horowitz et al. also evaluated the pattern of knowledge of oral cancer risks and diagnostic procedures. They used scores ranging from 0 to 3 and categorized the scores as low (0 7), medium (8 9), and high (0-3). Their results showed that 39% of dentists received a low score, 35% received a medium score, and 35% received a high score in the knowledge section. For knowledge about the procedure, the distribution was 35%, 44%, and 29% for the low, medium, and high score categories, respectively. They also observed that dentists who graduated from between 980 and 995 were about 2.5 times more likely to have a high score for knowledge of oral cancer and diagnostic procedures compared to those who graduated after

42 Their study found that dentists with higher levels of knowledge provided more favorable opinions about performing oral cancer examinations. They also found that knowledge of diagnostic procedures was associated with recentness of both graduation from dental school and participation in oral cancer education courses. They recommended that a requirement be set by the state of Maryland for minimum continuing education hours in topics related to oral cancer for licensure and relicensure. Although the idea of screening every patient was not practical, McGurk and Scott (200) suggested that selective opportunistic screening was a better option. The U.S. Department of Health and Human Services (HHS) released its objective for oral cancer examinations. Emphasis was placed on the importance of oral cancer examinations in order to increase the number of oral cancers detected at early stages (Centers for Disease Control, 206). Messadi, Wilder-Smith, and Wolinsky (2009) suggested that dentists should improve rates of oral cancer examinations especially in high risk populations. This invariably will promote oral cancer awareness and potentially detect oral cancers at early stages. Langevin et al. (202) suggested that there should be education of providers to ensure that oral cancer examinations are performed correctly with respect to palpation. Studies by Yellowitz et al. (2000) observed that although dentists were reportedly thorough with oral cancer examinations, they did not know what to look for or where to look when they perform oral cancer examinations. These practices lead to less detection due to lack of recognition of suspicious lesions. Geana, Kimminau, and Greiner (20) carried out a study on the knowledge and practices of health care providers. They 30

43 suggested that there was inconsistent knowledge of risk factors and signs of oral cancer. This translated into inconsistent oral cancer examination practices. The knowledge about oral cancer risk factors has been reported to bea predictor for awareness of the existence of an oral cancer examination (Cruz et al., 2005). Decuseara et al. (20) conducted a study in Ireland and found that the majority of Irish dentists identified alcohol and tobacco as the main risk factors associated with oral cancers. This was similar to studies in the United States, Canada, and Brazil (Clovis et al., 2002; Leão et al., 2005; Yellowitz et al., 2000). In Italy, respondents for a similar survey were aware of tobacco, alcohol usage, and prior oral cancer lesions as risk factors; however, only a few respondents were aware of the protective effect of fruit and vegetable consumption (Colella et al., 2008). Gajendra et al. (2006) found that a very high percentage of New York dentists and dental hygienists were aware that tobacco and alcohol are risk factors, but just a few knew about the protective effect of fruits and vegetables in preventing oral cancer. Irwin et al. (20) investigated the quality of oral cancer information on the internet. They hypothesized that a potential reason for the imbalance in content presentation may be the absence or dearth of basic information or research on various aspects of the disease (p. 3). They designed a strategy with the help of a Medline Plus search to identity websites about oral cancer and their quality of oral cancer information. Google and Yahoo were searched using the key words oral cancer, mouth cancer, and tongue cancer. The web search avoided and excluded professional and complex terms. The search calculated that 5-26% of website users for oral health were consumers while -7% were dentists. 3

44 Horowitz et al. (2002) carried out a qualitative study generated by two focus groups in Maryland: one face-to-face group session with ten dental hygienists in the Baltimore area and one telephone group with seven dentists who practiced on the Eastern Shore. They used criterion-purposeful sampling and qualitative content analysis. Six major factors emerged from the focus groups: ) dental hygiene; 2) lack of awareness of Maryland s oral cancer statistics; 3) level of training to provide oral cancer examinations; 4) provision of oral cancer examinations and barriers to not providing them; 5) reaction to Maryland surveys of dental hygienists on dentists assessment of oral cancer risk factors; and 6) interest in additional training. Most participants in Baltimore used words like mind boggling and shocking when told of the high incidence of oral cancer in Maryland. In contrast, participants from the Eastern Shore were not surprised. The training provided to carry out oral cancer examinations varied considerably in both groups. Some dental hygienists indicated that their formal training provided little or no training on oral cancer prevention and detection. The study also asked about the barriers to oral cancer examination and found that routine examination depended largely on dental hygienists confidence in their current skills and knowledge to conduct them Canto et al. (200) conducted a study of 800 Maryland general practice dentists to assess their knowledge of risk factors and diagnostic procedures for oral cancer. The data they obtained showed that nearly all respondents identified use of tobacco, prior oral cancer lesions, and use of alcohol as risk factors. The study showed that only 36% correctly identified that poorly-fitting dentures is not a risk factor, nearly 87% knew how 32

45 to examine the tongue and surrounding areas, and 32% identified erythroplakia and leukoplakia as conditions associated with oral cancer. The researchers concluded that appropriate knowledge about risk factors and diagnostic procedures is essential for dentists to counsel patients and perform appropriate oral cancer examinations. Gajendra et al. (2006) assessed the knowledge, practices, and opinions of dentists and dental hygienists in New York. Surveys were sent to a stratified random sample of dentists and dental hygienists selected from a list of licensed oral health care professionals. Results showed that 85% of dentists and 78% of dental hygienists reported providing annual oral cancer examinations to patients age 40 and older. They also observed that many dentists and dental hygienists lacked knowledge in some aspects of risk factors. They, however, observed that dentists had significantly higher knowledge than hygienists. Horowitz et al. (2000) observed a disappointing level of skills and knowledge in providing necessary and routine oral cancer examinations. They also observed that proper health histories were not being taken by dentists and thus called for comprehensive educational interventions which can be achieved by changing dental curriculum and providing continuing education after becoming licensed practicing dentists. Syme, Drury, and Horowitz (200) carried out a survey with Maryland dental hygienists and found that 99.7% correctly identified tobacco use as a risk factor and 59% identified alcohol use, but 3% incorrectly identified poor oral hygiene as a factor and 64% identified old age. Only 6% identified that the majority of oral cancer was detected in people age 60 and older. They also suggested the need for continuing education 33

46 courses to clarify risk factors and diagnostic procedures associated with early oral cancer detection and prevention. Reed et al. (200) investigated oral cancer preventive practices of South Carolina dentists and physicians. The study uses a cross-sectional survey. They reported that 8% of dentists and 3% of physicians agreed that they conduct oral cancer examinations at least half of the time patients came for a checkup. Forty percent (40%) of dentists and 37% of physicians were interested in receiving training on oral cancer screening. They suggested that tailored education of dentists and physicians to achieve the Healthy People 200 oral health objective should be organized. LeHew, Epstein, Kaste, and Choi (200) explored new methods for assessing in greater detail what dentists do when performing oral cancer examinations. They used a 38-item survey instrument ed to dentists in the western United States. They found that the mean of general knowledge was 0-4, while the mean for thoroughness in performing oral cancer examinations was.34. They also observed that when a test for significance was carried out on present knowledge and any recent continuing educational program attended, there was a significant association. Recent continuing education was also tested with thoroughness of carrying out oral cancer examinations and results showed that they were only marginally associated. Mahalaha, Cheruvu, and Smyth (2009) observed that the state of oral health in nursing homes was less than satisfactory and therefore there is a need to study knowledge, opinions, and practices of dentists working in these nursing homes. A crosssectional study was done to determine these variables using a 28-item questionnaire mailed to 75 dentists serving in 606 nursing homes throughout Ohio. They found that 34

47 younger dentists were more likely to have higher knowledge scores regarding oral cancer prevention when compared to older dentists. In Massachusetts, Applebaum et al. (2009) reported that 92% of dentists performed oral cancer examinations on patients aged compared to 49% of physicians. They also reported that 39% of dentists compared to 9% of physicians were able to identify the two most common sites where oral cancer develops. They also observed that 59% of dentists correctly identified the most common symptom of early cancer. They concluded that crucial gaps existed in the knowledge and practices among physicians and dentists and therefore a need to enhance oral cancer education among both professional groups. Patton, Elter, Southerland, and Strauss (2005) assessed the level of knowledge among dentists regarding risk factors and diagnostic concepts in dental practice. A 38- item questionnaire was sent to,5 licensed dentists practicing in North Carolina. Results showed that dentists who had higher risk factor and diagnostic knowledge scores were significantly more likely to have heard of one or more diagnostic aids (p < 0.05, OR 2.7). They were also more likely to have graduated within the previous 20 years and have performed biopsies or referred five or more patients with suspicious lesions per year. They suggested that more education is needed in dental schools, post graduate programs, and continuing education programs to enhance dental professional knowledge. Alonge and Narendran (2003) found inadequacy and ambivalence in respondents oral cancer knowledge and practices among dentists along the Texas-Mexico border. Mehdizadeh, Seyed Majidi, Sadeghi, and Hamzeh (204) evaluated the knowledge, attitudes, and practices of general dentists regarding oral cancer in Sari, Iran. 35

48 A cross-sectional study was performed on general dentists. They observed that age and period of practice since graduation had no correlation with the score obtained on knowledge of oral cancer and so they concluded that dentists of Sari have limited knowledge about oral cancer. Cruz et al. (2005) conducted a study to examine oral cancer prevention and early detection patterns in a population-based random sample of practicing oral health care professionals in New York. The results obtained showed that in terms of readiness to perform oral cancer examinations for patients older than age 40, 82% of dentists were in the practice of routinely screening for oral cancer. They concluded that dentists in New York seem to have adopted a routine oral cancer examination of patients but cancer prevention services, such as counseling regarding cessation of tobacco use and alcohol abuse, were still lacking. Theory and Conceptual Model There are several predisposing factors that could lead to an individual developing oral cancer, some of which are remote to the individual. Sociocultural and environmental factors play a major role which could expose the individual to risk behaviors that could lead to oral cancers. These risk behaviors include tobacco use, alcohol consumption, diet, HPV, poor oral hygiene, and poor oral health literacy among public and health care providers (Figure 6). Poor oral hygiene has also been implicated as a possible cause of oral cancer (Homann et al., 200). 36

49 Figure 6. Conceptual model. Research Question The question the researcher is trying to answer is: Among the dentists in Maryland who participated in the survey, will their knowledge of oral cancer prevention and screening have an association with their provision of oral cancer examinations and screenings? 37

50 Chapter 3: Methodology This section of the research illustrates the research design and methodology used in this study. The study is a mixed research, so the quantitative and qualitative analysis are discussed separately. The process of seeking for approval for the study will also be discussed and the researcher will end with discussing the study plan. Study Approval The researcher sought for approval from the principal investigator of a study that was conducted at the University of Maryland looking at the knowledge, attitude, opinions and practices of dentists. The Morgan State Intuitional Review Board (IRB) subsequently gave approval for the use of the data and for the qualitative aspect of the study. Research Design/Population and Sample - Quantitative Portion of Study A modified survey instrument created by researchers at the NIDCR and colleagues was used to collect the data for the quantitative analysis. Two new areas of interest were added to the original survey instrument. These areas included HPV as a risk factor for oral cancers and the use of adjunctive procedures in detecting and diagnosing oral cancers. Other questions in the instrument included dentist s biographic data, attitudes, practices, and knowledge regarding oral cancer prevention, and early detection and screening. The survey instrument and cover letter were mailed to,69 Maryland dentists who were randomly selected from the master membership list by staff at the Maryland State Dental Association (MSDA) in December The total number of Maryland dentists at that time was 2,500. Dentists were asked to complete and return the survey within two weeks of receiving it. After four weeks a second questionnaire was mailed to 38

51 all non-respondent dentists. The survey instrument was designed to be returned without an envelope, with the return address and postage printed on the back page of the survey instrument. It was discovered that 2 survey instruments were sent to the same people, hence the total number of survey instruments mailed were,57. A total of 69 completed questionnaires were received for a response rate of 56.3%. One hundred fifty six (56) surveys were invalid because the questionnaires mailed were incomplete and could not be used in the analysis; therefore, a total of 463 questionnaires were analyzed. Measurement of dependent variable. The dependent variable was dentist practices regarding oral cancer prevention. One question with four possible responses in the survey instrument addressed dentist practices in connection with oral cancer prevention. The question asked the respondent to provide the best estimate of the percentage of patients by age group for whom he/she provides an oral cancer examination at their initial (emergency or scheduled) and recall appointments for ages 8-39 and age 40 and older. The best practice estimates were divided into two groups for both initial and recall appointments. These groups include those who examined patients 00 of the time and those who examined less than 00% of the time. Independent variables. The independent variables included age, gender, year of graduation, and dentist s knowledge. Dentist s knowledge was based on 4 questions regarding what they know and understand about oral cancer and its prevention. The survey instrument can be found in Appendix A. A knowledge index score was generated assessing the 4 questions. These results were analyzed using Stata and divided into the following categories: low = 0-4, medium = 5-9, and high =

52 Statistical analysis. Stata c was used for analyzing the data. The data was audited and cleaned. Univariate analysis examining the raw data, frequencies, and percentages were explored. The factors associated with dentist s practices were explored. This factors included the knowledge of dentists, age, race, gender, practice setting, rating of undergraduate training, year of graduation, country trained and country born. Also, bivariate statistics to determine the relationship between dependent variable and the independent variables using percentages, chi square, and Fishers exact test were used to calculate the p value and confidence intervals. Simple logistic regressions (crude odds ratios) was performed since the outcome variable was dichotomous. Multiple logistic regression (adjusted odds ratios) was also used to predict the correlation between dentists practices and knowledge. Analytic Model As reflected in Figure 7, the independent variable is Maryland dentists practices regarding oral cancer prevention and early detection, while the dependent variable is the knowledge index score of the dentists regarding oral cancer prevention. The confounders and effect modifiers include dentists training, specialization, compensation, time, age, gender, and year of graduation. 40

53 Independent Variable Knowledge Dependent Variable Dentist s practices Confounders and effect modifiers Training, specialization, compensation, time, age, gender, year of graduation Figure 7. Analytical model. Qualitative Portion of the Study A total of four individuals participated in one-on-one in person interviews. A total of seven individuals were contacted, giving a response rate of 57%. Interviewees were purposively sampled to include a range in perspectives of key stakeholders who were involved in the transformational changes that occurred in Maryland regarding oral health care and cancer prevention during late Prior to the interview being conducted, participants were provided with key information, including the purpose of the research and consent for participation. All interviewees were asked in advance for their approval to audio-record the interview, therefore, allowing the researcher to accurately collect word-for-word responses from interviewees. All interviews lasted between 5-30 minutes. Questions for the semi-structured interview are listed in Appendix B. 4

54 Focus of inquiry. All interview questions focused on the following aspects of oral cancer in Maryland: Reduction of oral cancer mortality rates Current emphasis on oral cancer prevent and early detection Federal government s role The role dentists played Collaborations involved in reducing oral cancer mortality rates Interview data entry. All interviews conducted were audio-recorded to capture word-for-word responses from the interviewees. Once a key informant interview was conducted, the audio-recording was then transcribed in Microsoft Word in order to be analyze. The researcher also had a pen and paper where he took notes as the interview progressed. Qualitative data analysis of interviews. Qualitative data analysis of information for each one-on-one interview was based on phenomelogical method, allowing for codes to be developed as they emerged from within the interviews. Interview notes and interviews were analyzed for repetitious patterns of ideas generated from participant responses to the six questions asked. Analysis was completed by unitizing data, which included identification and recording of the units from the interviews that were relevant to the focus of inquiry. For each question asked, emerging themes were identified and coded for, allowing for categorization and constant comparison. Due to the small number of interviews, analysis was done first by reading through each paper copy of an interview and identifying emerging themes in the margin. Once this phase was complete, interviews 42

55 were coded and analyzed using a computer-assisted qualitative analysis software program called Atlas.ti. A list of codes was developed to represent the emerging themes resulting from participant responses to the six questions. Codes were constantly refined and merged as new themes emerged during analysis. Table is a list of the codes used to analyze the interviews. Table List of Qualitative Codes Q What did Maryland government do? Q3 Current emphasis in Maryland Qa Oral cancer prevention Q3a Not enough emphasis plan/legislation Qb Needs assessment surveys Q4 Maryland dentists role Qc Oral health screenings - are they Q4a Don t know/not sure being done correctly Qd Funding to local health department - Q4b Some took courses oral cancer projects Qe All started in mid 990s Q4c They don t get it/understand importance- not taught Qf Restricting tobacco, banning from places Q5 Collaborations involved Qg High taxes on alcohol, tobacco Q5a Friendships Qh Increased awareness Q5b NIDCR Qi Dental director position-obligated funds Q5c DHMH Q2 What did federal government do? Q6 Improve ranking Q2a Funding opportunities - money into Q6a Needs assessment (again) five states Q2b Listened to and supported champions Q6b More education provided for dentists, hygienists Q6c Improve dental school curriculum: oral cancer screenings Q6d Continue education for dentists and physicians 43

56 Data Analysis Plan After analyzing the quantitative secondary data, it will be followed up with the analysis of the qualitative data. The qualitative data analysis will hopefully help to explain some of the results that will be deduced from the quantitative analysis. The explanatory sequential mixed methods research will be used to analyze this research. Quantitative Data Results Qualitative Data Results Interpretation Following up Figure 8. Mixed methods explanatory research design. 44

57 Chapter 4: Results Quantitative Results The present study was aimed at accessing knowledge of oral cancer and its resultant effect on practice of oral cancer prevention and early detection by Maryland dentists. Frequency of dentist practices were divided into two categories: those who examined their patients 00% of the time and those who did not examine their patients 00% of the time. Other variables that were analyzed were age, gender, practice setting, rating of undergraduate training, year of graduation, country of birth, and country of dental training. The main outcome variables were dentist practices regarding oral cancer examinations at initial and recall visits for patients age 8-39 and age 40 and older. Table 2 displays the demographics of the participants in the study. A total of 456 dentists participated in this study. Among the participants, 349 (75.5%) were male while 07 (23.5%) where female. The majority of the participants were white (n = 380, 86%) and the fewest number were American Indians (n =, 0.2%). Asian/Pacific Islanders accounted for 8.% (n = 37), blacks accounted for 3.2% (n = 4), and Hispanics and other ethnicity accounted for 0.5% (n = 2) and 2% (n = 9), respectively. Participants were categorized according to age range: 20-29, 30-39, 40-49, 50-59, and The majority of the participants (40%, n = 83) were age Participants age represented the fewest number of respondents (2.6%, n = 2). One hundred and six (06, 23.%) respondents were age 60-69, while participants age accounted for 20.5% (n = 94) of respondents. 45

58 The majority (62.3%, n = 286) of dentists had a solo practice. This was followed by group private practice (36.4%, n = 67) and practice in community health centers and hospitals (0.7%, n = 3). Finally, the primary occupation of the participants was categorized as private practice dentist (98.5%, n = 452), dental school faculty/staff member (0.4%, n = 2), state or local government employee (0.7%, n = 3), and health/dental organization staff member and not in practice (0.2%, n = ). The dentists practices regarding oral cancer prevention and early detection measured at initial and recall visits for patients age 8-39 and those age 40 and older were used as the measuring indices. Table 2 Demographics of Surveyed Maryland Dentists Background Characteristics N Percent Gender (n = 456) Male Female Ethnicity (n = 442) White Black Hispanic Asian/Pacific Islander American Indian/Native Alaskan 0.2 Other Year of Graduation (n = 45) (Continued) 46

59 Table 2 Demographics of Surveyed Maryland Dentists (continued.) Background Characteristics N Percent Age (n = 458) Practice Setting (n = 459) Solo Practice Group private practice Community health center Hospital Primary Occupation (n = 459) Private practice dentist Dental school faculty/staff member State or local government employee Health/dental organization staff member 0.2 Not in practice/looking/waiting for licensure 0.2 Table 3 shows the frequency with which dentists carried out oral cancer examinations when patients age 8-39 years presented for initial oral cancer examination. The odds of examining a patient 00% of the time by a dentists with a high knowledge index was.73 compared to those with low knowledge index (8.78%, n = 75). Dentists with medium knowledge score also performed oral cancer examinations 00% of the time with an adjusted odds ratio of.53 compared to those with low knowledge index. The confidence interval was not statistically significantly different. Age was also analyzed with the highest percentage (83.46%, n = 227) of dentists examining their patients 00% of the time found in the age category. There was also no statistical significant difference between groups as all confidence intervals included. The majority of the male dentists (82.%, n = 280) compared to the female dentists (77.67%, n = 80) examine their patients who come for initial visits 00% of the time. 47

60 Dentists race was also examined. It was found that 28.33% (n = 7) of dentists from Other races did not examined their patient 00% of the time, though the difference was not statistically significant. Results also show no difference in practice between dentists who had a solo practice and those who worked in other settings such as group practice or hospitals. Most (85.62%, n = 3) dentists who claimed their undergraduate training was very good had higher odds of performing oral cancer examinations 00% of the time when patients age 8-39 came for an initial oral cancer examination. The difference between those who claimed they had very good training, good training, and poor training regarding oral cancer examinations at initial visits for patients age 8-39 was not statistically significant. When the results for year of graduation were analyzed, 83.80% (n = 269) of dentists who graduated during where twice more likely to examine their patients age 8-39 at initial visits 00% of the time than 72.88% (n = 86) of dentists who graduated during The bivariate analysis was statistically significant with a confidence interval of but was not significantly different in the multivariate analysis. There was no difference in the odds of examining a patient age 8-39 for oral cancer at initial visits based on country of birth. Dentists who trained in the United States had an odds ratio of.53 in performing an oral cancer examination at initial visits in patients age 8-39 compared to dentists who trained outside the United States. This was not statistically significantly as the confidence intervals included. 48

61 Table 3 Logistic regression of Performing Oral Cancer Examinations at Initial Visit in Patients Age 8-39 by Demographic Data Variables Knowledge Index Low Medium High Age Gender Male Female Race White Others Practice Setting Solo Practice Others Undergraduate Training Very good Good Poor Year of Graduation Country of Birth Other USA Country of Training Other Perform Exam 00% of the Time n (%) 8 (72) 75 (8.78) 73 (8.60) 5 (70.83) 227 (83.46) 83 (8.37) 280 (82.) 80 (77.67) 304 (82.6) 43 (7.67) 226 (80.43) 36 (8.93) 3 (85.62) 66 (78.67) 59 (76.62) 269 (83.80) 86 (72.88) 48 (75) 38 (82.7) Perform Exam < 00% of the Time n (%) 7 (28) 39 (8.22) 39 (8.40) 2 (29.7) 45 (6.54) 9 (8.63) 6 (7.89) 23 (22.33) 66 (7.84) 7 (28.33) 55 (9.57) 30 (8.07) 22 (4.38) 45 (2.33) 8 (23.38) 52 (6.20) 32 (27.2) 6 (25) 69 (7.83) Bivariate OR (95% CI).75 ( ).73 ( ) 2.08 ( ).80 ( ) 0.76 ( ).55 ( ).0 ( ) 0.62 ( ) 0.55 ( ) 0.52 ( ).08 ( ) Adjusted OR (95% CI)*.53 ( ).34 ( ).09 ( ) 0.9 ( ). ( ) 0.69 ( ). ( ). ( ). ( ) 0.53 ( ).30 ( ) USA 6 (80) 350 (8.2) 4 (20) 8 (8.79).53 ( ) *Adjusted for knowledge index, age, gender, race, practice setting, undergraduate training rating, year of graduation, country of birth, and country of training. P < ( ) Table 4 shows the frequency of performing oral cancer examinations in patients age 40 and older. The odds of performing an oral cancer examination based on knowledge index showed that 8.6% (n = 68) and 8.22% (n = 73) of dentists with 49

62 medium and high knowledge score, respectively, had an odds ratio of 2.4 compared to 64% (n = 6) of dentists with low knowledge score who performed an oral cancer examination 00% of the time in patients age 40 and older. The difference in oral cancer examination based on knowledge index was not statistically significant. Based on the age of the dentists, the odds of performing an oral cancer examination in all age groups was similar with the bivariate analysis but the odds of performing an oral cancer examination 00% of the time among 80.42% (n = 24) dentists aged was 0.69 compared to 78.87% (n = 56) of dentists age in the multivariate analysis. The difference was not statistically significant. The odds for examining a patient 00% of the time at initial visits for patients age 40 and older is similar for both male and female dentists with 80.42% (n = 27) for males and 79.2% (n = 80) for females. This was not statistically significant. The odds of performing an oral cancer examination 00% of the time is 0.65 among dentists of other races compared to Whites and is not statistically significant. There is also no statistical difference among practice setting. Rating of undergraduate training was analyzed with 83.33% (n = 25), 67% (n = 79.52), and 75%( n = 57) of dentists who rated their undergraduate training as very good, good, and poor performed oral cancer examination 00% of the time, respectively. The odds of examining a patient 00% of the time who is age 40 and older at initial visits was also analyzed, with 80.76% (n = 256) of dentists who graduated during performing oral cancer examinations compared to 78.63% (n = 92) who graduated during The difference in the practice of dentists based on country 50

63 of birth or country where trained was also not statistically significant in both bivariate and multivariate analyses. Table 4 Logistic Regression of Performing Oral Cancer Examinations at Initial Visit in Patients Age 40 and Older by Demographic Data Variables Knowledge index Low Medium High Age Gender Male Female Race White Others Practice Setting Solo Practice Others Undergraduate Training Very good Good Poor Year of Graduation Country of Birth Other USA Country of Training Other Perform Exam 00% of the Time n (%) 6 (64) 68 (8.6) 73 (8.22) 56 (78.87) 24 (79.85) 82 (8.9) 27 (80.42) 80 (79.2) 299 (8.25) 42 (73.68) 223 (8.09) 30 (78.3) 25 (83.33) 67 (79.52) 57 (75) 256 (80.76) 92 (78.63) 46 (75.4) 3 (80.99) Perform Exam < 00% of the Time 9 (36) 39 (8.84) 40 (8.78) 5 (2.3) 54 (20.5) 9 (8.8) 66 (9.58) 2 (20.79) 69 (8.75) 5 (26.32) 52 (8.9) 36 (2.69) 25 (6.67) 43 (20.48) 9 (25) 6 (9.24) 25 (2.37) 5 (24.59) 73 (9.0) Bivariate OR (95% CI) 2.42 ( ) 2.43 ( ).06 ( ).6 ( ) 0.93 ( ) 0.65 ( ) 0.84 ( ) 0.78( ) 0.60(0.3-.8) 0.88 ( ).39 ( ) Adjusted OR (95% CI)* 2.32 ( ) 2.9 ( ) 0.69 ( ) 0.95 ( ).5 ( ) 0.64 ( ) 0.77 ( ) 0.72 (0.40-,30) 0.54 (0.26-.) 0.79 ( ) 0.89 ( ) USA 4 (73.68) 343 (80.52) 5 (26.32) 83 (9.48).476 ( ) *Adjusted for knowledge index, age, gender, race, practice setting, undergraduate training rating, year of graduation, country of birth and country of training. P < ( ) 5

64 Table 5 shows the frequency of performing oral cancer examinations 00% of the time among patients age 8-39 who come for recall visits. The results show that 85.78% (n = 87) and 84.43% (n = 79) of dentists who had medium and high knowledge index, respectively, examined their patients 00% of the time at recall visits for patients age 8-39, with the odds of examining for oral cancer being.9 and.7, respectively, when compared to the 76% (n = 9) of dentists who had low knowledge index. This difference was not statistically significant. The age of dentists was also analyzed, with 88.32% of dentists age examining their patients age % of the time for recall visits. The odds of dentists age carrying out oral cancer examinations at recall visits for patients age 8-39 is 3.2 compared to dentists age This difference was not statistically significant. When analyzing dentists practice regarding oral cancer examinations among patients age 8-39 who come for recall visits, 80.95% (n = 85) of female dentists compared to 86.0% (n = 295) examine their patients 00% of the time, with an odds ratio of 0.69 (95% CI [ ]). With multivariate analysis, the odd ratio is increased to.24 among female dentists compared to male dentists. Regarding race, 85.75% (n = 39) of Whites compared to 77.42% (n = 48) of dentists from Other races examine their patients 00% of the time and this was not statistically significant. Many (85.80%, n = 45) dentists who worked in Other practices had an odds ratio of.5 (95% CI [ ]) of examining their patients 00% of the time at recall visits compared to 84.04% (n=237) of dentists working in solo practices. Bivariate and multivariate analyses regarding undergraduate training rating were analyzed as very good, good, and poor. Dentists who rated their training as poor (79.22%, 52

65 n = 6) had an odds ratio of 0.47 (95% CI [ ]) in the bivariate analysis. This infers that there is a statistical difference in practice between dentists who rated their undergraduate training as very good and those who rated theirs as poor regarding examining patients age % of the time at recall visits. There was also a statistically significant difference between 88.24% (n = 285) of dentists who graduated during (OR 0.40, 95% CI [ ]) and 75% (n = 90) of dentists who graduated during regarding oral cancer examination among patients age 8-39 who present themselves at recall visits. Regarding country of birth and country of training, United States dentists frequently examined their patients 00% of the time compared to those from Other countries. In both cases, about a quarter of dentists from Other countries did not examine their patients 00% of the time in patients age 8-39 and this was not statistically significant. 53

66 Table 5 Logistic Regression of Performing Oral Cancer Examinations at Recall Visits in Patients Age 8-39 by Demographic Data Variables Knowledge index Low Medium High Age Gender Male Female Race White Others Practice Setting Solo Practice Others Undergraduate Training Very good Good Poor Year of Graduation Country of birth Other USA Perform Exam 00% of the Time n (%) 9 (76) 87 (85.78) 79 (84.43) 52 (70.27) 242 (88.32) 87 (85.29) 295 (86.0) 85 (80.95) 39 (85.75) 48 (77.42) 237 (84.04) 45 (85.80) 39 (89.) 76 (83.02) 6 (79.22) 285 (88.24) 90 (75) 50 (75.76) 335 (86.2) Country of training Other USA 6 (76.9) 369 (85.02) Perform Exam < 00% of the Time n (%) 6 (24) 3 (4.22) 33 (5.57) 22 (29.73) 32 (.68) 5 (4.7) 48 (3.99) 20 (9.05) 53 (4.25) 4 (22.58) 45 (5.96) 24 (4.20) 7 (0.9) 36 (6.98) 6 (20.78) 38 (.76) 30 (25) 6 (24.24) 54 (3.88) Bivariate OR (95% CI).9 ( ).7 ( ) 3.2 ( ) 2.45 (.7-5.5) 0.69 ( ) 0.57 ( ).5 ( ) 0.6 ( ) 0.47 ( ) 0.40 ( ).98 ( ) Adjusted OR (95% CI)*.72 ( ).28 ( ).77 ( ).32 ( ).24 ( ) 0.92 ( ).26 ( ) 0.62 ( ) 0.4 ( ) 0.47 (0.9-.2).63 ( ) 5 (23.8) 65 (4.98).77 ( ) *Adjusted for knowledge index, age, gender, race, practice setting, undergraduate training rating, year of graduation, country of birth and country of training. P < ( ) 54

67 Table 6 shows the frequency of oral cancer examinations among patients age 40 and older who came for recall visits. Knowledge index score was analyzed using both bivariate and multivariate analysis and in both cases the analyses were statistically significantly among those with low, medium, and high knowledge index. The odds of 86.26% (n = 82) of dentists who have a medium knowledge index compared with 68% (n = 7) is Dentists from different age groups did not have any significant difference in examining patients age 40 and older who came for recall visits. Most (85.55%, n = 290) male dentists examined their patients 00% of the time compared to 82.35% (n = 84) of female dentists. This was not statistically significant. Regarding the race of dentists who examined patients age 40 and older for oral cancer, 85.4% (n = 36) of Whites compared to 82.76% (n = 43) of Others, examined patients 00% of the time, which was statistically insignificant. There was no significant difference in practice setting among dentists who were analyzed. Analysis of undergraduate training rating shows that 76.32% (n = 58) of dentists who rated their training as poor compared to 88.25% (n = 35) of dentists who rated their training as very good examined their patients 00% of the time. This was statistically significant (OR 0.42, 95% CI [ ]). The odds ratio of the year of graduation when comparing those who graduated during is 0.70 for the bivariate analysis and. for the multivariate analysis. Both ratios were not statistically significant. There was a statistical difference in practice regarding country of birth. The odds of examining a patient age 40 and older if they were born in the United States is.96 compared to Other dentists (95% CI [ ]). Most (85.08%, n=365) dentists who trained outside the U.S. examined their patients 00% of 55

68 the time compared to 73.68% (n = 4) of Other dentists who were not trained in the United States, with an odds ratio of Table 6 Logistic regression of Performing Oral Cancer Examinations at Recall Visits in Patients Age 40 and Older by Demographic Data Variables Knowledge index Low Medium High Age Gender Male Female Race White Others Practice setting Solo Practice Others Undergraduate Training Very good Good Poor Year of Graduation Country of Birth Other USA Country of Training Other Perform Exam 00% of the Time n (%) 7 (68) 82 (86.26) 80 (84.9) 57 (79.7) 233 (86.30) 85 (84.6) 290 (85.55) 84 (82.35) 36 (85.4) 48 (82.76) 233 (84.73) 43 (84.62) 35 (88.24) 79 (85.24) 58 (76.32) 96 (8.36) 275 (86.2) 47 (75.8) 332 (86.0) Perform Exam <00% of the Time n (%) 8 (32) 29 (3.74) 32 (5.09) 5 (20.83) 37 (3.70) 6 (5.84) 49 (4.35) 8 (7.65) 54 (4.59) 0 (7.24) 42 (5.27) 26 (5.38) 8 (.76) 3 (4.76) 8 (23.68) 22 (8.64) 44 (3.79) 5 (24.9) 54 (3.99) Bivariate OR (95% CI) 2.95 ( ) 2.65 ( ).66 ( ).40 ( ) 0.79 ( ) 0.82 ( ) 0.99 ( ) 0.77 ( ) 0.42 ( ) 0.70 ( ).96 ( ) Adjusted OR (95% CI)* 2.96 ( ) 2.22 ( ).5 ( ).0 ( ).04 ( ).5 ( ).02 ( ) 0.73 ( ) 0.38 ( ) 0.69 ( ).49 ( ) USA 4 (73.68) 365 (85.08) 5 (26.32) 64 (4.92) 2.04 ( ) *Adjusted for knowledge index, age, gender, race, practice setting, undergraduate training rating, year of graduation, country of birth and country of training. P < ( ) 56

69 Correlation between dentist knowledge and practice of oral cancer examinations was done for initial visits and recall visits for patients age 8-39 and age 40 and older. Correlation was positive for all, indicating that as knowledge increased practice increased, but the increase was not statistically significant. When knowledge was correlated with practice in Figure 9, the correlation coefficient was 0.03 and 0.06 for dentists practices for oral cancer examination at initial visits for patients age 8-39 and age 40 and older showing a positive correlation. This implies that as knowledge index increased, there was a non-significant increase in the frequency of practice of dentists when patients age 8-39 or age 40 and older presented themselves for initial dental examinations. Furthermore, for patient s age 8-39 who presented themselves for recall visits, when knowledge was correlated with practice, the coefficient was 0.02 compared to 0.05 which was seen at recall visits for patients age 40 and older in Figure 9. Therefore, if the dentist knowledge index increased, the frequency of carrying out an oral cancer examination was positively related for recall visits. For both initial and recall visit patients, there was a weak positive correlation with knowledge which can be seen in Figure 0 which was not statistically significant because all p values were greater than

70 den~t_9_39 know_i~x den_pct_in_.0000 know_index den~t_40 know_i~x den_pct_in_ know_index den~c_40 know_i~x den_pct_re_.0000 know_index den~c_9_39 know_i~x den_pct_re_ know_index Figure 9. Stata output of correlation between dentist s practices and knowledge index. 58

71 know_score know_score initial oral cancer examination for 9-39 years Fitted values initial oral cancer examination for 40+ years Fitted values know_score Recall oral cancer examination for 9-39 years Fitted values know_score Recall oral cancer examination for 40+ years Fitted values Figure 0. Scatterplots for correlations of oral cancer examinations at initial and recall visits with dentist knowledge score. Qualitative Results Seven researchers were approached for the in-depth interviews and of these, four agreed to be interviewed. From the interviews that were successfully conducted the following overarching themes were deduced from the six questions that were asked: Theme : The need for more education Theme 2: Importance of funding Theme 3: Importance of collaborations Theme 4: Importance of the Oral Cancer Prevention Plan 59

72 Theme 5: Importance of HPV and HPV vaccines in oral cancer prevention Theme 6: Importance of incentives in oral cancer screening Theme : The need for more education. The interviews revealed that more education is needed for dentists, physicians, nurses, dental hygienists, and dental students. Multiple interviewees discussed dentists lack of knowledge in regards to oral health cancer screening. In addition, interviewees specifically mentioned that medical providers and dentists do not know what to look for in the mouth during an oral exam. One interviewee in talking in reference to an oral cancer examination stated, They do not know where to look, they didn t know the two most common major sites to look for, and they didn t know the kind of lesions to look for. Another interviewee still referencing the knowledge of physicians talked not only about physician s lack of knowledge regarding oral health cancer screening, but also how this may be due to the changes in the type of education provided in medical and/or dental school: One of the problems with that is that most physicians are not really taught very well on how to examine the mouth. I mean things may have changed since my days but I came out of dental school when I went to medical school and did my MD. You know I think that the, umm, teaching on the oral cavity after four years sort of dental school in medical school was a one half hour lecture so most MDs are not as confident or as happy with examining the mouth as they are examining other parts of the body. Suggestions were made that oral cancer education should be included in dental student s curriculum. It also was suggested that dentists should attend continuing education courses, especially in oral cancer. For example, one interviewee indicated that doing an oral cancer exam should be necessary in order to receive a license, In order to 60

73 get your license to practice medicine or dentistry or hygiene or nurse practitioners that they have to demonstrate that they know how to do an oral cancer exam. This suggests that oral cancer screening skill sets be made mandatory as a requirement for receiving a license to practice medicine whether that be a medical provider or nurse, dentist or dental hygienist. This point was elucidated by another interviewer referencing the notion that what you continue to practice you will eventually be skillful in doing, Any kind of student, if they are trained to be competent in whatever axis and if they are trained to be competent in x, they are more likely to practice that on the outside. Interviewees also mentioned that increase the practice of oral cancer examination, that education would be a key component. The following are ways in which interviewees indicated that practitioners could gain the necessary education in to conduct an oral cancer exam: In medical school: The curricula of the dental and medical students would include emphasis in performing oral cancer examinations. Medical students should spend more time studying oral health since most times they are the ones that patients go to first when they have health related problems (Crossman et al., 206). Continuing education: Emphasis on continuing education also was made. That dentists should be required to attend continuing education courses on oral cancer to update their knowledge and skills annually. Inter-professional trainings: Successful interventions are carried out by multidisciplinary teams; hence the need to train professionals like dentists, physicians, dental hygienists, etc. in oral cancer examinations. 6

74 Educating patients also was emphasized because it was also referenced that the patients were not knowledgeable regarding oral cancer. For example, one interviewee stated, It was really terrible in that the majority of adults had no idea that there was such a thing as an oral cancer exam. Theme 2: Importance of funding. Another recurrent theme was the availability of funds. Findings showed that money had to be available for funding surveys and training practitioners to educate both practitioners and patients. It was also mentioned that when funding was available, educating young dentists and patients went well as noted by one interviewee This [effort] followed through for years but then, and then the oral health office also got additional kinds of money where they went out to baseball parks and educated. They did oral exams there. They educated the public at baseball games and they had enough money at the time to give to some of the counties to do some of these same things, to focus on oral cancer. Suggestions showed that if more funds are made available, then more interventions could be done to increase the level of knowledge, understanding and practice of carrying out oral cancer examination. One interviewee noted, If more funds are available then training could be organized in form of inter-professional training since most causes of oral cancer could be identified by physicians. Theme 3: Importance of collaborations. A major theme that was recurrent in all the interviews was the importance of collaboration between stakeholders in the community. Efforts were concerted from the federal, state, and local communities to ensure these changes occurred. Due to the high mortality and morbidity rates in Maryland, these coalitions were put together to make sure that these rates dropped. 62

75 According to one of the interviewees, These coalitions was formed to address high incidence and mortality rates for cancer in the states of Maryland. Another interviewee also said that this coalition developed a model of health prevention approach to be implemented in Maryland: And as part of that coalition, a model was developed using the Precede Proceed Model of Health Prevention approach to be implemented in Maryland and it had three phases: initial-assessment, implementation, re-evaluation (to assemble). The phase [was] included the assessment of the Department of Health getting some statistics by county. Based on the interviews, it can be inferred that coalitions were vital to the success achieved in the reduction of morbidity and mortality rates of oral cancer in Maryland. Men and women from all walks of life were incorporated into this coalition. For example one of the interviewees indicated that: We developed a small committee of all kinds of people. It was the American Cancer Society, University of Maryland, Office of Oral Health, NIDCR, NIDR at the time, and others as well and we worked together to do a number of things. Theme 4: Importance of oral cancer prevention plan. An oral cancer prevention plan was developed in the 990s during this period, a needs assessment was done on both medical and dental professionals. At that time it was observed that the Preventive Health Service Task Force did not see a benefit in carrying out an oral cancer examination annually on all individuals. Some researchers thought this was not correct since early detection of oral cancer could reduce mortality and morbidity. According to one of the interviewees: Screening tools [had] been pushed very hard by manufacturers for so called early detection. They ve included the brush biopsy, the visiline scan, the vinyl cyclo microscope, toluidine blue, and self-test kits now for HPV and the problem is that you know there is no really good evidence based literature that they do any good. In fact most of the series that have been done have shown really they don t make 63

76 any difference and that they are probably not effective so you could say well you know these things are not effective. It seems the Oral Cancer Prevention Plan made oral cancer a top priority among the health care issues that were addressed by Maryland government at that time. As time went by and funding for oral cancer prevention waned, the emphasis shifted to other health issues that had funding to be addressed. This was expressed by one of the researchers stating that, emphasis on oral cancer recently has dropped, the emphasis is now on children s oral health. Statements made by interviewees showed that oral cancer was not a priority since most people felt it was not a high profile cancer like breast or lung cancer. One interviewee stated, Well, I can say oral cancer is not really high on most people s list... A drop in oral cancer morbidity and mortality rates in Maryland was observed as the government kick started the Oral Cancer Prevention Plan. They used the funds from the class action tobacco law suit according to one of the interviewees: States had a windfall of money that came from it so most states use the windfall from this tobacco to do anything but cancer prevention and tobacco prevention but not Maryland. Maryland was one of the few states that truly used it to go into cigarette restitution fund and truly used it both try to prevent tobacco use and to prevent cancer. Theme 5: The importance of HPV and HPV vaccines in oral cancer prevention. The topic of HPV and HPV vaccines was mentioned by each of the interviewees, even when no question related to HPV was asked. The topic was usually mentioned in reference to increasing new cases of oral cancer especially in younger adults. Some of these statements can be found below: I think when you get your pap smear now they do HPV testing at the same time so if there is any positive result maybe just to let the women know so as to let their partners know or just to know their risk, i.e. education related to the risk side, not 64

77 just smoking and alcohol but also there is the human papilloma virus. Although the people with this virus have a low mortality rate compared to the related risk factors. I think more and more of what we should be doing is focusing on getting all kinds of health care providers to get more and more young people vaccinated for HPV. This is, to me, a major thing we should be doing. I do not think they are doing that much. In fact we are actually getting a little reenergized because of HPV because we re starting to work with there s a cancer program department and they re really working now on getting the word out about HPV, the vaccines essentially, and so we re beginning to get messaging out again starting to go back to tip toeing basically. Theme 6: Importance of incentives in oral cancer screening. Another theme that emerged in the interviews was that practitioners were also not particularly interested to carry out oral cancer examinations because they felt they were not being paid for the time spent doing the examination. Dental practitioners were more likely to spend time on patients when they know that the time spent will result in them being reimbursed. Several interviewees shared similar thoughts regarding reimbursement for oral cancer examinations: There s no fee for oral cancer exam so dentist don t get paid to do it so, you know, there is no financial incentive for them to do it so if there is a code and recognized fee for oral cancer screening then I think you may get more improvement. But a lot of dentist think they should get an extra fee for doing that oral cancer exam, but they don t do it because it does take a couple of extra minutes. If a dentist buys a brush biopsy kit or a visilie kit it raises their awareness and it makes them think that, oh, they should look at lesions in a slightly different way. So although they are using tools to screen that really lack good evidence based medicine behind them but I think that has the very fact that those things are out and this HPV test are out there has raised the awareness of the dentist. And if they are not reimbursed then they will not spend money to buy this screening tool, well if they can get reimbursed for these screening tests they can charge for those, okay, they can t get paid for an oral cancer exam but if they do a brush biopsy exam or whatever else they can charge the fees. 65

78 Based on the interviewees, it can be inferred that if dentists are incentivized, then there would be motivation for them to examine patients for oral cancer and it will also encourage them to invest in new investigative instruments that will enhance screening and early detection of oral cancer. These screening tools are expensive and if dentists are not reimbursed for the time they spend examining the patients they will not be encouraged to buy these tools according to one of the interviewees who said, And if there are not reimbursed then they will not spend money to buy this screening tool. Still on the aspect of incentivization of dental practitioners, one of the interviewees suggested that even dental health institutions are redistributing funds and concentrating on areas where there are more financial rewards as seen in private practices as stated below: We have to change the dental schools... See its one of those things that because there is not a lot of money in it, dental schools in my view like private practice they had to keep their heads above water and make money. So you know it s a hassle. 66

79 Chapter 5: Discussion This study was set to investigate the correlation between dentist knowledge about oral cancer and frequency of practice (i.e. examination of patients at initial and recall visits). In addition, qualitative data was collected by conducting one-on-one key informant interviews. To obtain the frequency of carrying out oral cancer examinations, patients were grouped into initial visits and recall visits. Furthermore, patients were also grouped based on age and 40 and older. Several articles have shown that if oral cancer can be detected early, then the mortality rate can be further reduced. The question then is, as a matter of public health concern, what will equip dentists in carrying out oral cancer examinations to detect lesions early? If they are knowledgeable about oral cancer and how to carry out an oral cancer examination, will they perform them more frequently? One of the interviewees called the men and women who helped see this success story come to fruition in Maryland champions. Champions of the Maryland model of oral cancer prevention were instrumental in the interventions that were carried out in Maryland. These champions had a common cause and worked to improve oral cancer ratings in Maryland. They worked alongside other coalitions to effect changes to morbidity and mortality rates in Maryland. It seemed to the researcher that beyond the common interest that these champions had was that they were also trusted colleagues and friends who had a shared vision that made the coalition work so well. Such coalitions cut across federal institutions like the NIDCR. The Maryland Department of Health and Mental Hygiene s role cannot be overemphasized as it was pivotal to the success in Maryland. NIDCR provided most of the funding, but also other institutions like the state 67

80 provided funds to see that it was successful. It is noteworthy that as the funding waned, emphasis in oral health shifted to other areas that had funding availability. The issue of dealing with oral health as though it is separate from the overall health of the person should be discouraged as this is not true. The oral cavity is the gateway to the body and a vital part of the human body. Funds pooled from various sources were used for training and educating all who cared to hear or learn something about oral cancer including medical and dental professionals. It is interesting that there was more funding for oral cancer in the 990s than what we have currently. This has led to a shift in the emphasis on oral cancer prevention to some other health prevention programs. Investing in public health interventions such as oral cancer prevention is not just a cost effective measure but will also provide a good return in investment. It has been shown that investing in proven public health preventive measures will save the U.S. billions of dollars annually (Maciosek, Coffield, Flottemesch, Edwards, & Solberg, 200). Questionnaires were mailed to dentists, and one of the questions asked was the frequency of oral cancer examinations, which is the outcome variable in this research. Dentists were expected to remember when patients visited for an oral cancer examination and whether patients were age 8-39 or age 40 and older. This was to ascertain if the age of the patient or when the patient visited the dentists played a role in the frequency of oral cancer examinations. Initial visits were defined as the first time the patient visited the dentist, while recall visit was the second or third time such a patient visited the dentist for an oral cancer examination. 68

81 From the study it was seen that if the patient was age 8-39 and was seen at initial visit, the frequency of a dentist carrying out an oral cancer examination 00% or less than 00% was dependent on some factors. These factors are age of the dentist, gender of the dentist, rating of undergraduate training, year of graduation, practice setting, the country of birth, and the country of training. This study analyzed 463 questionnaires of Maryland dentists who were 75.5% males, mainly Whites (86%), and worked in solo practices (62.3%). Forty percent (40%) of the dentists were age who were private practitioners (98.5%). Results showed that when patients age 8-39 presented for initial visits, certain variables were positively associated with carrying out oral cancer examinations 00% of the time. Dentists age were two times more likely to carry out oral cancer examinations 00% of the time in patients age 8-39 compared to dentists age (OR 2.08, CI [ ]) in the univariate analysis. Although the association was statistically significant in the bivariate analysis, this association was not significantly different in the multivariate analysis. Dentists from other races were 45% less likely to examine their patients age 8-39 at initial visits for oral cancer compared to White dentists. This result may be due to the fact that white dentists constitute 86% of dentists who were surveyed. For dentists who examined their patients age 40 and older for oral cancer, the researcher found out that those with medium and high knowledge index had an odds ratio of 2.44 and 2.43, respectively, compared to those that had a medium index score. The confidence intervals were borderline in both the bivariate and multivariate regressions. Younger dentists age frequently examined patients age 40 and older who came to the practice for oral cancer examinations. This may be because of the classical teaching 69

82 that oral cancer is more prevalent in patients older than age 40, hence they feel these patients are more at risk than younger patients. For recall visits of patients age 8-39 who came to the dentists for oral cancer examinations, it was also observed that dentists whose country of birth was the United States were twice more likely to examine their patients age8-39 for oral cancer compared to dentists from other countries. The age of the dentist was also a significant factor in examining patients age 8-39 who came to the practice for recall visits. Dentists who were older consistently had a higher odds of 2.5 or greater in examining their patients compared to dentists who were age The year of graduation of the dentist also showed some significance. Dentists who graduated during were 60% less likely to examine their patients age 8-39 at recall visits. This was consistent to what was seen at initial visits for patients age Also rating of undergraduate training showed that dentists who claim their undergraduate training was poor were 48% less likely to examine their patients for oral cancer. This correlates with what one of the interviewers said, Any kind of student, if they are trained to be competent in whatever axis and if they are trained to be competent in X, they are more likely to practice that on the outside. These dentists who rated that their undergraduate training was poor may have rated it as such because competencies in oral cancer screening practices might not have been emphasized in their undergraduate training. Patients age 40 and older presented themselves at recall visits at the dental practice and the knowledge index of dentist played a role in whether they were examined for oral cancer or not. Dentists with medium and high knowledge index were about three times more likely to examine their patients than those with a low knowledge index score. 70

83 Also dentists who were born in the United States were twice more likely to examine their patients age 40 and older than those born in Other countries. The rating of undergraduate training was also significant for dentists examining patients age 40 and older at recall visits. Dentists who rated their training as poor were about 60% less likely to examine their patients for oral cancer, which was similar to what was seen for recall patients age Some dentists who rated their undergraduate training as poor were consistently less likely to examine their patients From the study a positive correlation was observed when knowledge index was compared with frequency of oral cancer examinations. The age of the dentist notwithstanding, the frequency of carrying out oral cancer examinations increased as knowledge increased. This, therefore, confirms the existence of a positive association. The majority of young dentists carried out oral cancer examinations on older patients while older dentists carried out the examinations on both categories of patients. This trend is consistent with reports by Shiboski, Shiboski, and Silverman (2000). They reported that oral cancer was largely a disease of elderly people. The importance of changing the curriculum of dental schools was also mentioned during the in-depth interviews, and this would help to synchronize and update dental curricula so that emphasis is placed on graduating dentists with specific competencies, especially in oral cancer examination and early diagnosis. This study also observed that dentists with poor knowledge and poor training carried out oral cancer examinations less frequently, and these findings are consistent with studies by Gajendra et al. (2006). This was consistent with the qualitative results that dentists and medical practitioners had gaps in knowledge of oral cancer and hence not 7

84 confident in examining their patients. Lack of knowledge is a major delimiting factor in oral cancer prevention, both from the practitioner and also from the patient. A patient who is well informed will most likely request services than a patient who is not, and that was one of the reasons why the Maryland Oral Cancer Prevention Plan was very effective in that it empowered not just the practitioners and other health care providers but also the patient through trainings and seminars held across the state. As one of the interviewees mentioned, We spoke to whoever cared to listen. An issue that was mentioned in the qualitative results was HPV. HPV has been strongly correlated with oral cancers and there are many serotypes. One of the serotypes that causes cervical and oral cancer is Serotype 6. A vaccine has been developed for the prevention of cervical cancers and since it is the same serotype, it might be extrapolated that the same vaccine may be effective in the prevention of oral cancers. Also, overall results showed that U.S. trained dentists carried out oral cancer examinations more frequently and this concurred to research by Yellowitz et al. (998). They found that U.S. trained dentists confidently agreed that they were adequately trained to detect early oral cancer lesions. In this study, a relationship was seen between the time the dentist graduated and the frequency of carrying out an oral cancer examination. Dentists who graduated in the 990s frequently carried out oral cancer examinations when compared to dentists who graduated after 2000, but those who graduated after 2000 carried out oral cancer examinations more on recall visits of patients age 40 and older. These findings are similar to those reported in Ireland and Italy (Colella et al., 2008; Decuseara et al., 20). 72

85 Early diagnosis of oral premalignant or small cancerous lesions is very important for the successful management of oral cancers. That is the reason why dentists and physicians must regularly examine their patients. The issue of incentivization has been a common theme among dentists and physicians, but the truth is that a comprehensive oral examination includes an oral cancer examination and therefore no additional fee should be needed. Delay in diagnosis of oral cancers has been related to poor survival rates (Sandoval et al., 2009). In summary, results from this study are consistent with findings of prior studies on dentists in different geographical regions. Variation amongst dentist practices suggests the need for well laid out practice standards and training. These standards can be introduced in undergraduate training and reinforced as continuing education for practicing dentists. This study has delivered valued perceptions into the task of realizing asymptomatic diagnosis of oral cancer in its early stage. Young dentists in this study felt that most oral cancer patients were in age 40 and older, suggesting the reason they screened more of the older patients. Oral cancer patients are more likely to see a physician a number of times in a year for dissimilar medical matters in the asymptomatic phase before their diagnosis, suggesting a great opportunity for physicians to perform opportunistic oral cancer screening and the need to train physicians on how to look out for oral cancer. Research in the future should be focused on investigating the obstacles to and causes of late diagnosis in target populations. Furthermore, novel and innovative ways of carrying out opportunistic oral cancer screening should be developed. 73

86 The present study has emphasized significant confidence on the part of U.S. trained and U.S. born dentists in carrying out oral cancer screening, as the majority of dentists who carried out and who are likely to carry out an oral cancer examination are U.S. trained. This study has shown that Maryland dentists have an adequate level of knowledge of oral cancer, as well as an adequate level of skill in carrying out oral cancer screening examinations. With the present level of dentist knowledge and great confidence, it is unlikely that thorough visual and tactile oral cancer screening examinations will not be done, even in a non-high-risk individual. To encourage better rates of screening, practicing dentists need to continue to update their knowledge and should be in line with every modern literature and systematic review concerning oral cancer examinations. Also for oral cancer examinations to increase on the part of dentists in Maryland, interventions are desirable to expand the knowledge and confidence of dentists towards early detection and diagnosing of oral cancer. Strengths There have been several publications on this subject matter. These results have added to our understanding of what dentists know and do about oral cancer prevention. The survey instrument that was used to collect the data is a standardized questionnaire that has been developed and used by several authors with a little variation by adding questions regarding HPV. Most of the publications on this subject matter had either been based on qualitative or quantitative analysis. This is one of the first studies using a mixed methods approach. 74

87 Limitations Since the dentists had to report what was done in the past, there could have been some difficulty in recollecting the actual estimates. Some dentists could have just written what they think and not necessarily what they practiced. Also there could be some selection bias since not all the dentists responded to the questionnaire. The dentists who responded might have been the ones more interested in the subject and more comfortable with examining patients for oral cancer. In the selection of participants, dentists not currently in clinical practice on September, 2009, and dental specialists such as oral surgeons, orthodontists, and pedodontists were excluded from the study. Though the majority of patients go to general practitioners, it would have been good to have more diversity from the dentist practices. Responses from dentists who worked in specialist practices, hospitals, or government establishments would have added some more weight to the data even though this was deliberately omitted in the initial research question for designing the questionnaires. In addition, another limitation was the small number of interviews of key informants Recommendations From the present study, it is recommended that the level of knowledge should be used to reinforce frequency of practice. The level of knowledge could be improved by embedding the need for oral cancer screening in both undergraduate dental students and practicing dentists. Continuing education should be done by practicing dentists to improve their skills and update their knowledge on oral cancer and the latest procedures. 75

88 Standardized screening procedures should be formulated; knowledge and skills should be improved. Working across multi-disciplinary teams should be used as a means to getting lasting and effective results in public health interventions. Funds should be immediately made available for oral cancer prevention programs. The following are more recommendations for further research and interventions focused on the primary medical healthcare setting identified during the dissertation preparation and aimed at increasing the detection of asymptomatic, early-stage oral cancers and, ultimately, the survival of patients diagnosed with oral cancer. Investigate the curricula used in postgraduate and undergraduate medical school so as to establish the recent scope of oral medicine and pathology training thereby ensuring that the knowledge and skill needed in oral cancer examinations is properly taught and learned. Explore the most operational ways of training dentists and most especially physicians in risk factors of oral cancer, confidence in diagnostic procedures, and performance of oral cancer examinations is achieved. Examine the most operative means of raising awareness among the health practitioners and the public of oral cancer, its risk factors, and the availability of screening examinations. Consider ways of increasing awareness in high-risk target populations of oral cancer and the accessibility of screening examinations. 76

89 Investigate roles played by professional organizations in public awareness campaigns, health practitioner education interventions, and the development of policy to improve early detection of oral cancer. Involve the Preventative Health Taskforce with suggestions at any future opportunity to include early detection of oral cancer as part of future updates or revisions. This study and most literature reviewed have shown that a lot has already been achieved in dental healthcare settings in Maryland. Changing the deep-seated practice conduct of the Maryland dentist population toward oral cancer examinations is a great task that will necessitate determined energy both from persons and from specialized multidisciplinary societies. The laborious design and execution of additional research activities following the recommendations above will improve the early detection of oral cancer. If early stage diagnosis is to be achieved, then future research should be focused on improving oral cancer screening in the asymptomatic phase through appropriate screening strategies. The true clinical aim is to diagnose a lesion in the asymptomatic phase as either an OPML and OED or a small size tumor (Woolgar, 2006). 77

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114 Appendix A Questionnaire 02

115 03

116 04

117 05

118 06

119 07