Background: Salivary secretory IgA (sIgA) is said to play an important role in the immune response against dental caries. This study aimed to determine the salivary sIgA levels in healthy smokers and non-smokers, and its correlation with dental caries.
Methods: A total of 70 healthy subjects were selected and classified into four groups according to dental caries and tobacco smoking habits: smoking with caries (Group 1, n = 15); smoking without caries (Group 2, n = 15); non-smoking with caries (Group 3, n = 15); and non-smoking without caries (Group 4, n = 25). Salivary sIgA was measured using ELISA. The fissure and proximal caries were examined clinically and radiographically. Caries status was determined according to the decay surface index.
Results: Smokers showed a higher number of caries and the lowest concentration of sIgA. The highest levels of sIgA were observed in non-smoking and caries-free subjects compared to caries-active smokers (123.2 ± 19.9 vs. 13.3 ± 4.1 μg/ml respectively, p < 0.001). Also, the mean level of sIgA in Group 4 was significantly higher than Group 3 (p = 0.009). More importantly, higher and significant levels of sIgA were found in Group 3 versus Group 1 (p < 0.0001) and Group 2 (p = 0.0004).
Conclusions: Our findings indicate that low concentrations of salivary sIgA are correlated with a higher prevalence of dental caries in smokers.
© 2013 Australian Dental Association.