Environmental Tobacco Smoke and Dental Caries in South African Adolescents

Exposure to environmental tobacco smoke (ETS) or passive smoking has been associated with primary teeth caries in some developed countries, but little is known of this relationship in developing countries or in permanent dentition. Objective: To examine the relationship between permanent teeth caries in a population of adolescents and their exposure to smoking by a household member (HHM). Methods: Cross-sectional data obtained from a representative sample of 8th-graders from the Limpopo province, who had both dental examination and data on exposure to HHM smoking (N=1856). Socio-demographic data, information on smoking by any HHM, and history of dental care including daily sugar intake and brushing frequency were obtained through a self-administered questionnaire. Data analysis included chi-square statistics and logistic regression. Main outcome measure: Caries experience in a permanent tooth using the WHO diagnostic criteria. Results: The mean (±SD) age of the respondents was 14.6 (±1.6) years and 89.5% were black Africans (50.1% female). The mean DMFT was 0.69 and significant caries index (SiC) was 2.07. Of the respondents, 22.4% had at least one decayed tooth and 36.8% reported at least one HHM smoking. Compared to those who did not report smoking by HHM, those who reported smoking by HHM were significantly more likely to present with a decayed tooth (29.1% vs. 18.3%; p < 0.001). After adjusting for age, race, gender and dental visits history, exposure to HHM smoking remained significantly associated with dental caries (odds ratio [OR], 1.63; 95% confidence interval [CI] 1.30 - 2.05). Other significant determinants of dental caries included sugar intake ≥ X4 daily (OR=1.37; 1.06 - 1.78), living with only the mother (OR=0.67; 0.50 - 0.88) and being in the highest income rank (OR=1.78; 1.20 - 2.65). Conclusion: Study findings suggest that reduction of ETS may be important for the promotion of dental health among South African children.