Original Article OPEN ACCESS Knowledge of dental fluorosis of undergraduate dental at a private university in Brazil Juliana De Oliveira Ferla, DDS. 1, José Augusto Rodrigues, DDS, MS, PhD. 1, Eduardo dos Santos Leonetti, DDS. 1, Kenitiro Suguio, PhD. 2, Jamil Awad Shibli, DDS, MS, PhD., Alessandra Cassoni, DDS, MS, PhD. 1 Departments of Restorative Dentistry 1, Geoscience 2 and Periodontology, School of Dentistry Guarulhos University, São Paulo, Brazil. Citation: Ferla JDO, Rodrigues JA, Leonetti EdS, Suguio K, Shibli JA, Cassoni A. Knowledge of dental fluorosis of undergraduate dental at a private university in Brazil. North Am J Med Sci 2010; 2: 71-7. Doi: 10.4297/najms.2010.271 Availability: www.najms.org ISSN: 1947 2714 Abstract Background: The understanting of the dental fluorosis process, that begins with enamel maturation, is important to Dentistry, since fluoride has drastically decreased the incidence of caries in several population groups, with a resultant increase in fluorosis prevalence and severity, as shown in literature. Aims: The objective of this paper is to report the changes in the level of knowledge about dental fluorosis of undergraduate Dentistry at Guarulhos University. Subjects and Methods: One hundred and twenty-four undergraduate enrolled in the first and second semester and seventh semester were evaluated. The data was obtained through questionnaires with dichotomic questions (true and false) and an alternative to evaluate whether the subject had been presented in the classroom. The data obtained was submitted to statistical analysis using the Chi-square test (α=0.0). Results: When evaluating the first semester, differences were verified in numbers of the questions assigned with the alternatives true or false, when compared with seventh semester (p<0.001). However, there were no differences when the same questionnaire was applied to the first semester after six months (p=0.8). Conclusions: It is possible to conclude that the six months period was insufficient to increase the level of knowledge about dental fluorosis, and when the beginning and concluding the dentistry course were compared, there was an increase in the number of correctly assigned true or false questions in the latter group. Keywords: Dental fluorosis, dentistry education, undergraduate of dentistry, follow up. Correspondence to: Alessandra Cassoni, Universidade Guarulhos, Pós-Graduação em Odontologia, Praça Teresa Cristina, 9, Centro - Guarulhos - SP, Brazil - CEP 0702-070. Tel./Fax: ()2464178, Email: acassoni@prof.ung.br Introduction Exposure to fluoride throughout one s lifetime is essential for preventing caries. Beltran-Aguilar et al. [1], in a summary to the United States Surveillance Center for Disease Control and Prevention, affirmed that for the majority of permanent teeth, enamel fluorosis is hipomineralization of the enamel related to exposure to fluoride during tooth formation, during the first six years of life. Fluorosis is the side effect of excessive (systemic) fluoride ingestion, and presents as an enamel defect manifested as stains and/or puntiform stains in tooth enamel [2]. 71 In a study on the perception of dental fluorosis, the observers felt that its appearance could embarrass children according to the increase in severity of the enamel alterations. With the exception of dentists, ordinary people are led to believe that more severely stained enamel could indicate children s negligence in caring for their teeth []. Moderate fluorosis is accepted as a side effect of water fluoridation, and more recently, has been recognized as a consequence of another caries prevention strategy based on fluoride. The Secretary of Health of the State of São Paulo (Brazil), in partnership with universities, developed an
Epidemiological Survey on Oral Health in 1998 [4], and dental fluorosis was also evaluated in school children of, 12 and 18 years of age, when a mean prevalence of.2% was found. In practically all the Regional Health Boards (RHB) (Diretorias Regionais de Saúde DIR), the prevalence of fluorosis did not exceed 20% at the studied ages. Ritter [2] affirmed that studies have indicated a prevalence of between 2 and 12% of dental fluorosis in communities with fluoridated water supplies. Through an evaluation of persons between the ages of 2- years and between 6-9 years in the United States, from 1999 to 2002, it was concluded that 2% presented a moderate or higher degree of dental fluorosis. An increase of around 9% in the prevalence of a moderate or higher degree of dental fluorosis was observed among persons from 6-19 years of age when the 1990-2002 data were compared with researches conducted between 1986-1987 among school children, since it increased from.8% in the period from 1986 to 1987 to 2% in the period from 1999 to 2002 [1]. A study of dental fluorosis perception by means of using intra- and extraoral photographs of individuals with variable degrees of severity was conducted by means of descriptors of personal characteristics. The characteristics used for describing fluorosis varied with the degree of severity, which were also significantly influenced by the intra or extraoral view and by the degree of suggestion to mention the mouths of individuals with fluorosis []. Another interesting aspect as regards the perception of dental fluorosis was approached in a study of adolescents, as the esthetic acceptability diminished with the increase in the degree of fluorosis presented in digital images, which became more acceptable with the increase in distance [6]. Toassi & Abegg [7] reported on the prevalence and severity of dental fluorosis in 29 school-age children between 4 and 18 years, in the Municipality of Santa Tereza (Rio Grande do Sul, Brazil) and investigated the possible associated causes. The data was collected by means of a questionnaire and a clinical exam, using the Dean index. The prevalence of fluorosis was 6.7%, among which the predominant degree was very slight, 4.6%; followed by the slight degree, 12%; moderate, 7.7%; questionable, 7.% and severe, 0.4%. Around 8% of these persons had access to the use of fluoride in the present or past. Significant associations were found between places of residence, practice of using fluoridated mouthwashes in the past or present, and the prevalence and severity of fluorosis, as well as between the prevalence of fluorosis and the parents educational level, in addition to the frequency of brushing, access to fluoridated mouth washes and the use of fluoride gel (p < 0.0). In a study conducted in 2002, with the aid of questionnaires about computer generated photographs, changes in the perception of Dentistry about 72 dental fluorosis and other conditions were reported among with fourth-year and those at the beginning of the course. Fourth-year are generally more likely to perceive the esthetic appearance of moderate fluorosis and other conditions than at the beginning of the course [8]. Knowledge of the causes, diagnosis and treatment of stains caused by fluorosis are important to Dentistry course, although there is no information whatsoever about the acquisition of knowledge about dental fluorosis in current literature. The objective of this study was to report on the changes in the degrees of knowledge about dental fluorosis among undergraduate in the Dentistry Course at a Brazilian University. Subjects and Methods This research is of an exploratory nature, based on a quantitative approach. The undergraduate course in Dentistry at the Guarulhos University is concluded in 8 study semesters, in accordance with the ethical requirements of Resolution 196/96 of the National Health Counsel, Ministry of Health of the Federative Republic of Brazil (Brazil, Ministério da Saúde) [9], and it was approved by the Research Ethics Committee of the Guarulhos University. Ninety participated in the study (48 of the Day Course and 42 of the Night Course) in the first (1 st ) semester of 2008, and 4 of the seventh (7 th ) semester of 2008 (2. percent male/ 67. percent female). The same questionnaire applied in the first semester of 2008 was answered in the second (2 nd ) semester of 2008. Due to the absence of several for different reasons, 40 Day Course (8.%) and 2 Night Course (76.19%) were involved in the research. The data obtained was statistically analyzed by the Chi-square test at a % level of significance. The participating signed a free and informed term of consent, with the right to desist at any time, without any prejudice whatever. The criteria for suspending or closing the research were lack of personal interest, transfer, or desisting from the Dentistry Course of Guarulhos University during the course of the research. The questionnaire applied was pre-tested in the researched group. The results were obtained by means of a questionnaire, consisting of ten items (Table 1) and 4 options. The could select an alternative in each affirmation: A, B, C or D. Dichotomic alternatives (True - A and False - B) and two alternatives to evaluate whether the content had been taught in the classroom and presented to the ( don t remember received the information, but don t remember, alternative C and don t know didn t receive this information, alternative D). The results were compared and the data was statistically analyzed by the Chi-square test at a % level of
significance (α=0.0). Results Statistical analysis of the results allowed one to conclude that there were significant differences between the replies of 1 st Semester in comparison with those of the 7 th Semester (p<0.001). Nevertheless, no significant differences were found in the replies of the 1 st Semester, even after six months had elapsed (p=0.8). In Figure 1, the percentages of alternatives checked by 1 st Semester in 2008 are represented, and Figure 2 shows those checked by 7 th semester. Finally, Figure shows the alternatives checked by 2 nd semester in 2008. Fig. 1 Percentages (%) of alternatives checked by 1 st semester in Table 1 shows the percentages of correct answers found for enrolled in the 1 st, 7 th and 2 nd semester with the results obtained in each question evaluated. Discussion The use of fluoride to promote oral health involves a balance between the doses that provide protection against caries and diminish the risk of developing fluorosis. Exposure to fluoride in childhood is important for caries prevention, but there is the risk of dental fluorosis. The concept of fluorosis as hipomineralization seems to be well established among the Dentistry at Guarulhos University, as the rates of alternatives checked as A or B (True or False) are high (Figures 1 to ) for Question 1. Similarly, the concept that fluorosis affects the enamel, which was approached in Question 2, presented a correct answer rate of around 88% among 7th Semester (Table 1). On the other hand, beginning the dentistry course had high rate of wrong questions assigned for this topic (6%) and six months later this fact was similar (69% of wrong questions assigned). Zeedyk et al. [10] observed that in general, tooth brushing performed by parents was unsatisfactory, although the parents believed they were efficiently cleaning their children s teeth. These facts suggest that in a large number of cases, the dentists expectations with regard to tooth brushing are not met, even with the use of fluorides, and it is seriously compromised as a method for reducing caries in children, in spite of the practice of tooth brushing being implemented at an increasingly early stage. Nowadays children are exposed to innumerable sources of fluoride, and each of these has an unknown balance of risks and benefits. It is crucial to identify and maintain an efficient balance between the benefit of protection against caries and fluorosis, for the Dental professional and population to have confidence in the use of fluoride. Fig. 2 Percentages (%) of alternatives checked by 7 th semester in According to Bowen [], the transitory or initial stage of maturation of development is when the tissue is most susceptible to the changes induced by fluoride. As regards the permanent anterior teeth, especially those that are esthetically involved (maxillary central incisors), the critical period for ingesting higher doses of fluoride occurs in individuals in the age group between and 26 months of life. The dietary fluoride content in a community with fluoridated water generally ranges in value from 0.04 to 0.07 mg/kg per day. It is recommended that for reconstituting babies' powdered formula, the water should contain low quantities of fluoride (< 0. ppm fluoride). Fig. Percentages (%) of alternatives checked by 2 nd semester in 7 According to Browne et al. [12], the critical periods in which teeth are more exposed to the risk of developing dental fluorosis is between 1-24 months of age for boys and 21-0 months of age for girls. There are evidences showing that according to age, brushing with fluoridated dentifrice and the quantity of dentifrice placed on the brush are important risk factors for the incidence of
fluorosis. It is recommendable that brushing with fluoridated dentifrice should not be started before the age of two years, and after this age, around 0.2 g of dentifrice should be placed on the brush, corresponding to approximately a grain of birdseed. The cause of dental fluorosis and the possible ingestion of fluoride through dentifrices was inquired in questions and 8 respectively. The 7 th Semester showed correct answer rates of and 78% to these questions (Table 1). Table 1 Frequencies and percentages (%) of A or B (True or False) responses checked by 1 st, 7 th and 2 nd semester in 2008 concerning fluorosis and affirmation presented to Students enrolled in the Dentistry Course at the Guarulhos University. Question Affirmation presented to Students of the Dentistry Course at the Guarulhos University 1 st semester 7 th semester 2 nd semester 1 Dental fluorosis is considered a hipomineralization. (True) 7 70% 16 0% 1 1 0 71% 12 29% 2 Dental fluorosis affects enamel and dentin. (False) % 40 6% 29 88% 4 12% 16 1% 6 69% The cause of dental fluorosis is the excessive ingestion of fluoride up to the age of years. (True) 6 8% 26 42% 2 4% 21 46% 4 There are different degrees of fluorosis. (True) 6 1 27 0 1 Depending on the degree of severity in which dental fluorosis is presented; the regions of the affected dental elements could require intervention by the dentist. (True) 6 We can point out microabrasion as a treatment alternative for dental fluorosis. Microabrasion consists of etching performed with 6.% hydrochloric acid and must be performed by Dentistry Professionals. (True) 7 The index of fluoride in the water supply in Brazil is around 1 ppm. (True) 8 Fluoride ingested mainly from dentifrices is a possible cause of dental fluorosis. (True) 9 Dental fluorosis is normally found in equal quantities in both posterior and anterior teeth. (False) 10 The differential diagnosis between fluorosis and hypoplasia could take into account the presence of stains in homologous teeth. (True) n = frequency Al-Sugair & Akpata [1] conducted research about the effects of fluorosis on the pattern and depth after acid etching of human enamel. They concluded that teeth with more severe fluorosis required a longer etching time, because after 4 seconds the organic subsurface was evident, but the typical etching pattern appeared again when the time was increased to 7-90 seconds. The concept related to the degrees of severity of fluorosis is well established among the of the Dentistry Course at Guarulhos University, because the alternative relative to this question (4) had a high rate of correct answers in all the groups evaluated (Table 1) and low rates of alternatives the alternatives C ( don t know ) or D ( don t remember ) checked in all groups (Figures 1, Figure 2 and Figure ). Question concerns the Dentist s intervention, and was clear to the, because high percentages of correct answers were found in all the groups (Table 1). When hydrochloric acid (6.%) is applied to human enamel, it can correct defects up to 0.2 mm deep and it is called microabrasion technique. It can be applied and polished with a rubber cup for 60 seconds, when fluorosis 74 98% 0 96% 88% 19 61% 7% 2 44% 17 8% 2% 2 4% 12% 1 9% 2% 2 6% 1% 84% 0 91% 7 44% 17 8% 2 78% 8% 27 100% 16% 9% 9 6% 1% 7 % 4 1% 0 0% 98% 4 90% 19 86% 18 86% 81% 1 8% 24 8% 2% 10% 14% 14% 19% 24 62% 17% stains are removed without damaging the enamel structure [14]. However, in Question 6, many checked items C ( don t know ) or D ( don t remember ) in all the groups evaluated. This fact is notable in Figure 2 of the 7 th Semester, in which 1% checked the alternatives C or D. The authors foresaw this result, since the undergraduate course does not contemplate this subject related to the treatment of fluorosis by microabrasion. In Figures 1 (72%) and (71%), one observes that alternatives C or D were also frequently checked by at the beginning of the course. Question 7 deals with the fluoride content in water supplies in Brazil, which is around 1ppm. According to Figures 1 (62%) and 2 (70%) the at the beginning of the course mainly checked Alternatives C or D. On the other hand, the rate of correct answers of in the last year was 8%, according to Table 1, showing that this knowledge was acquired during the course. Question 9 discusses the differences in the rates of incidence of dental fluorosis between posterior and anterior teeth. Students at the beginning of the course
showed error rates between 6% and 62% (Table 1), when they checked as True, the affirmation that equal numbers of anterior and posterior teeth are affected. Question 10 deals with the criterion of differential diagnosis between fluorosis and hypoplasia, in which many of the in the beginning of the course checked the alternatives C ( don t know ) or D ( don t remember ) according to Figures 1 and. On the other hand, 79% of in the last year preferentially checked A (True) or B (False) (Figure 2). The percentage of correct answers to this question was 100% (Table 1) to the latter group, showing that the acquired this knowledge during the progress of the course. Comparison of the numbers of questions with True or False answers between 1 st and 7 th semester (p<0.001) clearly demonstrated that the level of knowledge about dental fluorosis increased during the course. No statistical differences were found when the questions applied to 1 st Semester were compared with those submitted after six months, suggesting that the time that had elapsed was insufficient for statistically significant increase to occur in the level of knowledge about dental fluorosis. According to Narendran et al [1] improved knowledge of fluorides among health care professional can maximize dental caries prevention and minimize deleterious effects as dental fluorosis. Conclusion It was concluded that the time interval of one semester was not sufficient to increase the level of knowledge about dental fluorosis. However, comparison of the at the beginning of the course with those at the end of it, clearly demonstrated improvement, as there was a larger number of that checked the questions of True or False alternatives. References 1. Beltran-Aguilar ED, Barker LK, Canto MT, et al. Centers for diseases Control and prevention (CDC). Surveillance for dental caries, dental sealants, tooth retention, edentulism, and enamel fluorosis-united States, 1988-1994 and 1999-2002. MMWR Surveill Summ 200; 4:1-4. 2. Ritter AV. Talking with patients - dental fluorosis. J Esth Rest Dent 200; 17: 26-27.. Riordan PJ. Perception of dental fluorosis. J Dent Res 199; 72: 1268-1274. 4. Núcleo de Estudos e Pesquisas de Sistemas de Saúde/Núcleo de Apoio ao Desenvolvimento de Sistemas de Saúde. Levantamento Epidemiológico em Saúde Bucal: Estado de São Paulo, 1998. São Paulo: Secretaria do Estado da Saúde de São Paulo/Faculdade de Saúde Pública, Universidade de São Paulo; 1999.. Williams DM, Chestnutt IG, Bennett PD, Hood K, Lowe R. Characteristics attributed to individuals with dental fluorosis. Community Dent Health 2006; 2: 209-216. 6. Edwards M, Macpherson LMD, Simmons DR, Gilmour WH, Stephen KW. An assessment of teenager s perceptions on dental fluorosis using digital simulation and web-based testing. Community Dent Oral Epidemiol 200; : 298-06. 7. Toassi RF, Abegg C. Dental fluorosis in schoolchildren in a county in the mountainous region of Rio Grande do Sul State, Brazil. Cad Saude Publica 200; 21: 62-6. 8. Levy SM, Warren JJ, Jakobsen JR. Follow-up study of dental ' esthetic perceptions of mild dental fluorosis. Community Dent Oral Epidemiol. 2002; 0: 24-28. 9. Conselho Nacional de Saúde. Resolução 196/96 do Conselho Nacional de Saúde sobre a regulamentação da pesquisa em seres humanos. Brasília: Ministério da Saúde; 1997. 10. Zeedyk MS, Longbottom C, Pitts NB. Tooth-brushing practices of parents and toddlers: a study of home-based videotaped sessions. Caries Res 200; 9: 27-.. Bowen WH. Fluorosis: is it really a problem? J Am Dent Assoc 2002; 1: 140-1407. 12. Browne D, Whelton H, O Mullane D. Fluoride metabolism and fluorosis. J Dent 200; : 177-186. 1. Al-Sugair MH, Akpata ES. Effect of fluorosis on etching of human enamel. J Oral Rehabil 1999; 26: 21-28. 14. Allen K, Agosta C, Estafan D. Using microabrasive material to remove fluorosis stains. J Am Dent Assoc 2004; 1: 19-2. 1. Narendran S, Chan JT, Turner SD, Keene HJ. Fluoride knowledge and prescription practices among dentists. J Dent Educ 2006; 70: 96-964. 7