Association of passive smoking with caries and related salivary biomarkers in young children

ObjectiveTo investigate the association between passive smoking, as determined by salivary cotinine level, and caries, salivary pH, buffering capacity, flow rate and microbiological counts in young children.DesignNinety passive smokers (PS) with a mean age of 5.02 years and 90 healthy age-matched controls were included in this study. Family income, smoking habits of household members, parental education levels, child's tooth-brushing habit and child's daily dietary sugar exposure were recorded by questionnaire. Three categories were formed with respect to the number of cigarettes smoked. A dmft score was calculated according to the criteria recommended by the World Health Organization. The children were also investigated for stimulated salivary cotinine level, pH, flow rate, buffering capacity and salivary Streptococcus mutans and lactobacilli colonisation.ResultsThere were no significant differences in tooth-brushing habit, sugar exposure, family income and parental education levels between the two groups (P > 0.05). The mean cotinine level of the PS subjects was 1.58 ± 4.3 ng/ml. The dmft scores, and salivary S. mutans and lactobacilli colonisation in PS children were significantly higher than in the control subjects (P < 0.05). Statistically significant decreases in salivary pH, flow rate and buffering capacity were found in the PS subjects (P < 0.05).ConclusionPS children are at increased risk of caries compared with control subjects.