Dental students attitude towards anti-smoking programmes: a study in Flanders, Belgium

Eur J Dent Educ 2007; xxx: 1 7 All rights reserved ª 2007 The Auths. Journal compilation ª 2007 Blackwell Munksgaard european journal of Dental Education Dental students attitude towards anti-smoking programmes: a study in Flanders, Belgium J. Vanobbergen, P. Nuytens, M. van Herk and L. De Visschere De Pintelaan 185, Ghent, Belgium Objective: The aim of the study was to assess the dental students attitude towards tobacco cessation counselling in the dental setting and to exple the influence of knowledge, belief in effectiveness, smoking status, gender and curriculum. Material and methods: The study group consisted of all undergraduate students from the 2002 2003 classes of the Ghent University (n ¼ 96). A validated questionnaire was administered to all students involving four different sections: demographic characteristics, attitude related to tobacco cessation programmes in the dental setting, belief in their effectiveness and knowledge concerning tobacco health effects. Statistical analysis included simple univariate nonparametric tests f evaluating differences in attitude towards tobacco cessation programmes, belief in effectiveness of tobacco cessation programmes in the dental setting and knowledge of students concerning tobacco health effects by of graduation, smoking status and gender. Multiple logistic regression was chosen to calculate adjusted odds ratios and 95% confidence intervals. Results: Students view willingness to advise individual patients to quit using tobacco. Yet only 51.3% are willing to co-operate in anti-tobacco programmes at the community level, and the perception of students of the effectiveness of smoking cessation counselling in the dental setting is low. The variance of attitude towards tobacco cessation programmes was significantly affected by knowledge and the belief in effectiveness of tobacco cessation programmes in the dental setting. Better knowledge and belief in effectiveness of tobacco cessation counselling was associated with an increasing positive attitude towards tobacco cessation programmes expressed by an odds ratio of 3.12 (95% CI 1.00 9.67) and 1.17 (95% CI 1.00 1.37) respectively. Conclusion: Belief in effectiveness and knowledge seem to influence the attitude of students towards tobacco cessation counselling. Practice implications: Besides imparting knowledge, the attitude of newly graduated dentists could be improved by stressing the effectiveness of smoking cessation activities during lectures and integrated training modules in the undergraduate education. Key wds: tobacco control; dental students; attitudes; patient counselling. ª 2007 The Auths Accepted f publication, 3 January 2007 Introduction S moking has an imptant negative effect on health. Accding to the most recent estimate by the Wld Health Organization (WHO), 4.9 million people wldwide died in 2000 as a result of their addiction to nicotine (1). Tobacco use also causes serious al health problems. It is firmly established that tobacco use is a primary cause of many al diseases and adverse al conditions (2). Tobacco is a risk fact f al cancer, al cancer recurrence, adult periodontal diseases and congenital defects such as cleft lips and palate in children (3, 4). The dental team can play an imptant role in tobacco control programmes, both, directed towards the community as a whole towards the individual patient. Through participation in community and political action and in counselling their patients to E J E 4 5 6 B quit, the health professional, in particular the dentist and his/her team, can contribute to a me tobaccofree society. Besides the imptant impact of national and international legislation, there is ample evidence that general medical practitioner advice to quit tobacco use is respected by the majity of patients, and several recent studies show that the effts of dentists can be equally effective (5 7). The problem is that, while the majity of dentists believe that providing infmation about tobacco cessation and offering smoking cessation suppt are both part of their duty, fewer dentists actually do so. The reasons f not providing it include time and reimbursement issues, po education and lack of further postgraduate training and po co-dination of dental and smoking cessation services (8 10). Another matter of research is the attitude of dental students, the future dentists, towards tobacco control Dispatch: 14.6.07 Journal: EJE CE: Ponjesuraj Journal Name Manuscript No. Auth Received: No. of pages: 7 PE: Kajalakshmi 1

Vanobbergen et al. programmes. Even when some reservations are mentioned, USA dental students appear to be positive regarding their responsibility to educate patients about the risks of tobacco use. There was a general agreement that their educational programme adequately prepared them to help smokers quit (11 13). The majity of Australian dental students planned to advise patients about tobacco use, although their perception of the effectiveness of smoking cessation counselling seems to be low (14). The same trend was observed in Europe where Greek students considered tobacco cessation counselling a duty f every dentist, 2 although an impted part (32%) believed it to be ineffective. On the other hand, students showed significant knowledge on tobacco health effects (15). The high rate of smoking among healthcare professional students in Hungary, Eastern Europe (16), compared with Western European, American and Australian students, could be an explanation why they are less proactive regarding tobacco intervention. The effectiveness of training health professionals to deliver smoking cessation interventions to their patients has been reviewed recently and repted in the Cochrane database. The auths concluded that training health professionals to provide smoking cessation interventions had a measurable effect on professional perfmance but that there was no strong evidence that it changed smoking behaviour (17). At least there is an agreement that students attitude will be influenced by peers, teachers and curriculum content. The educational system s movement towards prevention and holism is a trend that deals with the relevant themes in our changing society and that can contribute to the development of students attitudes. The refmation of the dental and medical curriculum at Ghent University switched the traditional biomedical ientation into a me biosocial iented and integrated approach: patient-centred; student-centred; community iented; problem and evidence based. Within this new dental curriculum, attention is paid to al health promotion, including tobacco cessation counselling. Yet tobacco cessation counselling is taught only in theetical terms during the second of the education. This refmation should be beneficial in reienting dental students attitudes towards a me positive attitude regarding health promotional and educational programmes (18). The aim of the present study was to assess the dental students attitude towards tobacco cessation promotion in the dental setting and to exple the influence of knowledge, belief in effectiveness, smoking status, gender and curriculum. Material and methods The study group f the present study comprised the dental students from the 2002 2003 classes of the Ghent University. Dental education programme at the Ghent University consists of two first-cycle s (bachel) and three second-cycle s (master). All undergraduate students (n ¼ 96) participated in the study with 25 students in the first, 25 in the second, 13 in the third, 11 in the fourth and 22 in the final. The final students went through their undergraduate education in the old curriculum. As, from this moment, the new curriculum was entered progressively, comparison between curricula is possible. A questionnaire was administered to all students (Fig. 1). This questionnaire was designed with four different sections: demographic characteristics, attitude related to tobacco cessation programmes in the dental setting, belief in their effectiveness and knowledge concerning tobacco health effects. In the first section respondents were asked about their age, sex, actual smoking status and undergraduate level. Non-smokers and ex-smokers were classified as non-current smokers, moderate/social and heavy smokers as current smokers. In the second section, a seven-item tool generated a total sce f attitude related to tobacco cessation programmes in the dental setting, both on an individual and on community level. This sce was calculated by totalising the yes responses and was further standardised to a maximum of 10 [(number of positive answers/number of questions) 10], a higher sce indicating a me positive attitude. F use in the logistic regression analyses this variable was dichotomised with the median value as the cut-off. The third section comprised items dealing with students belief in effectiveness of tobacco cessation programmes in the dental setting. Two yes no closeended questions and one rank dering question were used to assess this item. The rank dering question asked the respondents to rank, in der of imptance in the tobacco counselling process, a list including healthcare wkers, family, friends and the media. All three questions had the same weight (maximum 1 minimum 0). The rank dering question was sced from 0 (the dentist ranked in the last place) to 1 (the dentist ranked in the first place). This variable was further handled the same way as the variable attitude. In the last section 19 questions were included assessing students knowledge concerning tobacco health effects, in particular al health effects. This variable was calculated as the sum of crect answers 2

Belgian dental students attitude towards tobacco control Graduation :.. Age: Gender: o male o female Smoker: o never o in the past o moderate/ social smoker o heavy smoker 1. Are you willing to show your patients the damage that smoking can cause upon al health? 2. Are you willing to show your patients the damage that smoking can cause upon general health? 3. Are you willing to fbid the patients to smoke in the waiting-room of your own practice? 4. Are you willing to advise patients to stop smoking? 5. Are you willing to cooperate actively in anti-tobacco programs on community level? 6. Are you willing to use anti-tobacco programs in your own practice? (e.g. flyers, advisement, etc.) 7. Do you think that every dentist has the duty to cooperate in anti-tobacco programs? 8. Do you think that anti-tobacco programs in the dental practice can be effective? 9. Do you think that the patients will take notice of your advisement? What/who has the greatest influence on smoking behaviour: (classify from 1 to 10, starting with 1 = of greatest influence and 10 = of smallest influence) School Commercials on the street Doct Friends Colleagues Dentist Do you think that smoking: 1. -can cause a nose polyp? 2. -can cause lung cancer? 3. -can slow down al wound healing? 4. -can slow down growing? 5. -can cause nefropathology? 6. -can increase an existing periodontal pathology? 7. -can cause cancer of the oesophagal tractus? 8. -can cause al cancer? 9. -can cause liver-dysfunction? 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. -combined with alcohol has an increased risk of al cancer? -can cause al implant failure? -on elder age influences saliva-constitution? -of selfmade-cigarettes is wse than filter-cigarettes? -occurs me in upper class of the society? -during the pregnancy can cause breathing problems on the newly bn child? -influences al candidiasis? -influences leukoplakia? -influences taste sensitivity? -influences the amount of saliva? Fig. 1. Questionnaire (translated from the iginal Dutch). and standardised to a maximum of 10. The questions in this section were checked f relevance and the evidence of the answer was based on data directly 3 addressing the question (2,3) (19 25). The questionnaires were administered anonymously during scheduled class times and/ clinical courses. The questionnaire was pilot-tested pri to the study. The relevance of questions, response fmats and wding was tested. The process resulted in some questions being deleted and others being changed. A test retest with 10 students, spread over the graduations s, smoking status and gender, was perfmed to assess the reliability of the questionnaire with an interval of 1 month. Test retest measures (intra-class crelation) were combined with nonparametric tests f related samples and were used f the sum sces of attitude, belief in effectiveness and knowledge (Table 1). The Wilcoxon signed rank test was used to measure systematic differences between the two related measurements. F knowledge a significant systematic increase was 3

Vanobbergen et al. TABLE 1. Reliability measurement f sum sces related to knowledge, belief in effectiveness and attitude (n ¼ 10) Test mean (SD) (up to a max. of 10) Retest mean (SD) (up to a max. of 10) P-value 1 ICC Attitude towards tobacco cessation counselling 6.8 (2.1) 7.3 (2.2) 0.08 0.97 Belief in effectiveness of tobacco counselling 6 (1.4) 5 (2.3) 0.26 0.89 programmes in the dental setting Knowledge concerning tobacco health effects 5.9 (0.7) 6.6 (1.2) 0.048 0.69 ICC, intra-class crelation coefficient. 1 Wilcoxon signed rank test. found at the retest compared to the first test (P < 0.05). The survey was analysed using the SPSS 12.0 software package. Descriptive statistics were generated f relevant items. Univariate analysis was perfmed with nonparametric Kruskal Wallis and Mann Whitney tests. Multiple logistic regression analyses were carried out to determine the facts that were independently related to the attitude towards tobacco cessation programmes, belief in their effectiveness and knowledge of students concerning tobacco health effects. Data were analysed as dichotomous variables (except f age and of graduation ) and compared using odds ratios. Point estimates and 95% confidence intervals were calculated. Odds were calculated in one group (e.g. males) by dividing the number of males with e.g. high knowledge by the number of males with low knowledge. This odds calculation was repeated f girls. The odds ratio was obtained by dividing the odds of having a high knowledge among males by the odds of having a high knowledge among girls. Statistical significance level was set at P < 0.05. Results Response rate was 81% (78/96). Respondents were 62% female and 38% male. The average age of the sample was 21.79 (SD 4.16) s. Seventy-five per cent of respondents repted to be non-smokers. A narrow majity of the students (53.8%) had an explicit positive attitude towards tobacco cessation programmes, receiving an average rating of at least 7.5 out of 10 (a sce of 10 is the best possible attitude) on the responses related to this item. All respondents agreed to show their individual patients the al health hazards of tobacco use and 96% of respondents were willing to use anti-tobacco programmes in their practice to advise patients to quit using tobacco. However, only 40% of respondents agreed that it is the responsibility and duty of every dentist to co-operate in anti-tobacco programmes and only 51.3% are willing to co-operate actively in anti-tobacco counselling programmes at the community level. Based on the descriptive analyses of the responses related to the effectiveness of tobacco cessation activities in the dental setting, one can observe that the mean sce of all respondents was clearly lower compared with the mean sces of attitude and knowledge (5.1 vs. 8.1 and 8.3 respectively). Only 32% of the respondents had a sce equal to higher than 7 on the 1 to 10 scale. Figure 2 shows the different values f the three imptant outcome variables (attitude, belief in effectiveness and knowledge) during the 5 s of the undergraduate education. In the univariate analysis (Table 2) some relevant crelations were observed among the studied variables. There was a significant difference in attitude depending on the level of belief in effectiveness (P < 0.05). In fact, the me students believe in the effectiveness of tobacco cessation programmes, the me likely they are to have a positive attitude towards these programmes. Furtherme, a trend was observed towards a better attitude in students with a higher knowledge (P ¼ 0.09). A slightly different situation is observed f belief in effectiveness, where female students were shown to have a higher Value 10.0 9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0.0 1st 2nd 3rd 4th Graduation 5th Attitude Belief in effectiveness Knowledge Fig. 2. Attitude towards tobacco counselling in dental settings, belief in effectiveness and knowledge concerning tobacco health effects by of graduation. 4

Belgian dental students attitude towards tobacco control TABLE 2. Univariate analysis f differences in attitude towards tobacco cessation programmes, belief in effectiveness of tobacco cessation programmes in the dental setting and knowledge of students (n ¼ 78) concerning tobacco health effects by of graduation, smoking status and gender Attitude Belief in effectiveness Knowledge Mean P-value Mean P-value Mean P-value Graduation 0.36 1 0.74 1 <0.01 1 5 First 82 5.5 7.8 Second 7.9 5.6 7.9 Third 8.9 5.3 8.9 Fourth 7.8 4.1 8.7 Fifth 7.8 5.0 8.5 Curriculum 0.34 2 0.66 2 0.19 2 New curriculum 8.2 5.2 8.2 Old curriculum 7.8 5.0 8.5 Smoking status 0.24 2 0.64 2 0.44 2 Current smoker 7.7 4.8 8.4 Current non-smoker 8.2 5.3 8.3 Gender 0.35 2 <0.05 2 0.97 2 Female 8.2 5.4 8.4 Male 7.9 4.7 8.3 Belief in effectiveness <0.05 2 Less effective 7.7 Effective 8.3 Knowledge 0.09 2 0.55 2 Low knowledge 7.7 5.5 High knowledge 8.3 5.0 1 Kruskal Wallis test. 2 Mann Whitney test. belief in effectiveness of tobacco counselling than their male counterparts (P < 0.05). F knowledge the only significant crelation found in the data was the effect of graduation level (P < 0.01). No differences were found between final students (old curriculum) and the others (new curriculum). Logistic regression models determined the independent impact of demographic facts (gender, smoking status, level of graduation and age) on knowledge of students concerning tobacco health effects, attitude towards tobacco cessation programmes and belief in effectiveness of tobacco cessation programmes in the dental setting. These models explained about 18% of the variance of the outcome variable (R 2 ¼ 0.18, 0.18 and 0.17 respectively). They indicated that knowledge increased with of graduation, but not necessarily with age (Table 3). The odds ratio f increasing knowledge per was 2.03 (95% CI 1.20 3.44), representing a significant increasing knowledge during the undergraduate education with a peak between the second and the third (first and second cycle). The variance of attitude towards tobacco cessation programmes was significantly affected by knowledge and the belief in effectiveness of tobacco cessation programmes in the dental setting. Better knowledge and belief in effectiveness of tobacco cessation counselling was associated with an increasing positive attitude TABLE 3. Logistic regression model with knowledge, attitude towards tobacco cessation programs and belief in effectiveness of tobacco cessation programs in the dental setting as dependent variables adjusting f gender, smoking status, of graduation and age Explanaty variable Attitude Knowledge Effectiveness P-value OR 95% CI P-value OR 95% CI P-value OR 95% CI Gender Male vs. female 0.83 0.89 0.31 2.51 0.87 0.91 0.30 2.75 0.23 0.54 0.20 1.50 Smoking status Smoker vs. non-smoker 0.51 0.68 0.22 2.16 0.91 0.88 0.25 3.10 0.62 0.75 0.31 2.34 Year of graduation 0.23 0.75 0.48 1.19 <0.01 2.03 1.20 3.44 0.44 0.84 0.54 1.30 Age 0.96 1 0.84 1.18 <0.05 0.76 0.61 0.96 0.91 0.99 0.86 1.18 Belief in effectiveness 0.05 1.17 1.00 1.37 Attitude 0.09 2.22 0.89 5.97 Knowledge 0.05 3.12 1.00 9.67 0.44 0.65 0.22 1.95 Constant 0.84 0.72 0.02 96.80 0.82 1.44 Nagelkerke R 2 ¼ 0.18. 5

Vanobbergen et al. towards tobacco cessation programmes expressed by an odds ratio of 3.12 (95% CI 1.00 9.67) and 1.17 (95% CI 1.00 1.37) respectively. Discussion and conclusion Discussion When interpreting the results of this study one has to take into consideration some limitations. First, notwithstanding the high response rate, the 78 students represent a rather small sample. The number of incoming dental students in Flanders is actually very low. During a national campaign a few s ago, pursued by the dental association, young people were dissuaded from attempting a dental career. This resulted in a political debate followed by the restriction of the intake of students to the programmes of medicine and dentistry in Flanders through an entrance examination. Second, the development and implementation of the present study was conducted in only one dental school (there are two dental schools in Flanders). Thus, the findings repted in this study may have a limited generalisability and the power of the study may be limited. Non-response bias was evaluated but no significant differences were found between non-responders and responders in gender, of graduation and smoking status. Nevertheless, the results may reveal imptant infmation about Flemish dental students attitude, beliefs and knowledge towards tobacco cessation counselling in the dental setting. Compared to the current literature, smoking prevalence of dental undergraduates in the University of Gent remains high with 25% of the students being current smokers. Unftunately, smoking prevalence increased progressively with the of study from 12.5% in the first to 38.1% in the final, which goes against the trend observed in several international repts (12). In comparing current smokers with non-smokers, no differences in attitudes, beliefs and knowledge were observed, which is in agreement with the literature. Approximately two-thirds of the respondents were female, reflecting the actual trend towards increasing numbers of females in dental schools all over the Western wld. The only gender difference observed in the univariate analysis was that females tended to have me confidence in the effect of tobacco counselling in the dental setting. Gender was one of the confounders included in the logistic regression model, but no gender differences were found in the multiple analyses. The fact that 96% of students were willing to advise patients to quit using tobacco is consistent with the results of previous studies mentioned in the Introduction, but it seems remarkable that a lower percentage of them (40%) repted that it is their responsibility and duty to co-operate in anti-tobacco programmes. Knowledge seems to influence the attitude of dental students, but the very wide confidence interval may threaten the validity of this finding. The low mean sce observed f belief in effectiveness indicates that respondents have low confidence in the fact that tobacco counselling offered in the dental office can have an impact on patients quitting. This rather low perception of effectiveness follows the general trend repted in the literature (13 15). These responses suggest that many students may still be sceptical about the extent to which tobacco cessation counselling is effective in helping patients to quit. Much remains to be done in the undergraduate education to show the scientific evidence on both the efficacy and cost-effectiveness of tobacco prevention. Standardised and simple schemes, such as the Four As, are widely used around the wld, and advice on how to use this scheme is available. Here too, there is ample evidence proving that dentists advice to quit tobacco use is respected by the majity of patients (26, 27). The present study shows that belief in effectiveness of tobacco cessation counselling may also contribute to the attitude of students towards tobacco counselling. It is all the me reason why the effectiveness of tobacco programmes should be emphasised in the dental curriculum. So far, the effect of the new curriculum on students attitude, belief and knowledge has been minimal. As suggested in the literature one may need me alternate teaching methods such as problem-based discussions, tutials, small group discussion and skills labaties to improve the awareness, belief and skills of dental students, especially in this matter, in which attitudes play a significant role. Gradually these alternate methods will be implemented in the new curriculum, recently once again adapted to the Bologna agreement. However, the follow-up period in the present study was too sht to reveal the longer term effects of the new curriculum. Further research will be carried out to evaluate this new BaMa 4 structure. Conclusion Dental students attitude towards tobacco cessation counselling in the dental setting represents a promising baseline f future tobacco cessation programme development. Students view willingness to advise 6

Belgian dental students attitude towards tobacco control individual patients to quit using tobacco. Yet only a minity are willing to co-operate in anti-tobacco programmes at the community level, and the perception of students of the effectiveness of smoking cessation counselling in the dental setting is low. Knowledge and belief in effectiveness seem to influence the attitude of students towards tobacco cessation counselling. Practice implications Besides imparting knowledge, the attitude of newly graduated dentists could be improved by stressing the effectiveness of smoking cessation activities during lectures and integrated training modules in the undergraduate education. Both aspects, the community-based programmes and the individual communication skills, need to be emphasised. References 1. Petersen PE. The Wld Oral Health Rept 2003: continuous improvement of al health in the 21st century the approach of the WHO Global Oral Health Programme. Community Dent Oral Epidemiol 2003: 31 (Suppl. 1): 3 23. 2. Petersen PE. Tobacco and al health the role of the Wld Health Organization. Oral Health Prev Dent 2003: 1: 309 315. 3. Reibel J. Tobacco and al diseases. Update on the evidence, with recommendations. Med Princ Pract 2003: 12 (Suppl. 1): 22 32. 4. Little J, Cardy A, Munger RG. Tobacco smoking and al clefts: a meta-analysis. Bull Wld Health Organ 2004: 82: 213 218. 5. Warnakulasuriya S. Effectiveness of tobacco counselling in the dental office. J Dent Educ 2002: 66: 1079 1087. 6. Johnson NW. The role of the dental team in tobacco cessation. Eur J Dent Educ 2004: 8 (Suppl. 4): 18 24. 7. Carr AB, Ebbert JO. Interventions f tobacco cessation in the dental setting. Cochrane Database Syst Rev 2006: 1: CD005084. 8. Monaghan N. What is the role of dentists in smoking cessation? Br Dent J 2002: 193: 611 612. 9. Allard RH. Tobacco and al health: attitudes and opinions of European dentists; a rept of the EU wking group on tobacco and al health. Int Dent J 2000: 50: 99 102. 10. Allard RH. The role of health professionals in discouraging tobacco use. Ned Tijdschr Tandheelkd 2004: 111: 396 399. 11. Yip JK, Hay JL, Ostroff JS, Stewart RK, Cruz GD. Dental students attitudes toward smoking cessation guidelines. J Dent Educ 2000: 64: 641 650. 12. Fried JL, Reid BC, DeVe LE. A comparison of health professions student attitudes regarding tobacco curricula and interventionist roles. J Dent Educ 2004: 68: 370 377. 13. Victoff KZ, Dankulich-Huryn T, Haque S. Attitudes of incoming dental students toward tobacco cessation promotion in the dental setting. J Dent Educ 2004: 68: 563 568. 14. Rikard-Bell G, Groenlund C, Ward J. Australian dental students views about smoking cessation counselling and their skills as counsells. J Public Health Dent 2003: 63: 200 206. 15. Polychonopoulou A, Gatou T, Athanassouli T. Greek dental students attitudes toward tobacco control programmes. Int Dent J 2004: 54: 119 125. 16. Nagy K, Barabas K, Nyari T. Attitudes of Hungarian healthcare professional students to tobacco and alcohol. Eur J Dent Educ 2004: 8 (Suppl. 4): 32 35. 17. Lancaster T, Silagy C, Fowler G. Training health professionals in smoking cessation. Cochrane Database Syst Rev 2000: 3: CD000214. 18. Deveugele M, Derese A, DeMaesschalck S, Willems S, Van Driel M, De Maeseneer J. Teaching communication skills to medical students, a challenge in the curriculum? Patient Educ Couns 2005: 58: 265 270. 19. Bergstrom J. Tobacco smoking and chronic destructive periodontal disease. Odontology 2004: 92: 1 8. 20. Whitefd L. Nicotine, CO and HCN: the detrimental effects of smoking on wound healing. Br J Community Nurs 2003: 8: S22 S26. 21. Vehemente VA, Chuang SK, Daher S, Muftu A, Dodson TB. Risk facts affecting dental implant survival. J Oral Implantol 2002: 28: 74 81. 22. Macgreg ID. Effects of smoking on al ecology. A review of the literature. Clin Prev Dent 1989: 11: 3 7. 23. Sudbo J, Samuelsson R, Risberg B, et al. Risk markers of al cancer in clinically nmal mucosa as an aid in smoking cessation counselling. J Clin Oncol 2005: 23: 1927 1933. 24. Charalabopoulos K, Assimakopoulos D, Karkabounas S, Danielidis V, Kitsis D, Evangelou A. Effects of cigarette smoking on the antioxidant defence in young healthy male volunteers. Int J Clin Pract 2005: 59: 25 30. 25. Khan GJ, Mehmood R, Salah UD, Ihtesham UH. Effects of long-term use of tobacco on taste recepts and salivary secretion. J Ayub Med Coll Abbottabad 2003: 15: 37 39. 26. Havlicek D, Stafne E, Pronk NP. Tobacco cessation interventions in dental netwks: a practice-based evaluation of the impact of education on provider knowledge, referrals, and pharmacotherapy use. Prev Chronic Dis 2006: 3: A96. 27. Silagy C, Stead LF. Physician advice f smoking cessation. Cochrane Database Syst Rev 2001: 2: CD000165. Address: Prof Jacques Vanobbergen De Pintelaan 185 Ghent Belgium 9000 Tel: +39 9240 4025 Fax:??? 1 e-mail: Jacques.vanobbergen@Ugent.be 7

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