Dental caries in relation to smoking and the use of Swedish snus: epidemiological studies covering 20 years (1983-2003)

Objective. The aim of this study was to evaluate some intra-oral caries-associated variables and tobacco use on dental caries. Materials and methods. The participants were randomly recruited from three cross-sectional studies in Jonkoping, Sweden, in 1983, 1993 and 2003. Each study consisted of 130 individuals in each of the 20, 30, 40, 50, 60 and 70-year age groups. Of these, 550, 552 and 523 dentate individuals attended respective year of examination. They were all examined both clinically and radiographically. A questionnaire was completed in conjunction with the examination. In the studies, 345 were smokers, 104 snus users and 1142 non-tobacco users, in total 1591 individuals. Results. In 1983 and 1993, there were no significant differences in mean DFS between non-users and smokers, but a statistically significantly higher mean DFS in comparison with snus users. In 2003, there was no statistically significant difference in mean DFS between the groups. Multiple regressions showed that, after adjusting for age, gender and socio-demographic variables, there was a statistically significant association between DFS and smoking in 1983 (smoking excluded in favour of lactobacilli when further analysed) and DFS and plaque index (PLI) in 1993. In 2003, there was no association, apart from buffer capacity (Power rising) between DFS and the examined intra-oral caries-associated variables and tobacco use. Conclusions. The results of these epidemiological studies, performed in 1993 and 2003, indicate that daily smoking or snus use does not increase the risk of dental caries.