Background
Saliva contains a number of protective factors such as mucins, immunoglobulins (e.g., IgA, IgG, and IgM), and enzymes (e.g., lysozyme and lactoperoxidases) that play an important role in the maintenance of oral health. The aim of this study was to compare levels of sIgA, histatin-5, and lactoperoxidase in saliva of adolescents with dental caries.
Material and Methods
Thirty-five adolescents (age 18 years) from high school were examined. Eight subjects with DMF=3 (Group I) and 27 adolescents with DMF>11 (Group II) were enrolled for this study. Clinical evaluation procedures comprised oral examination (including tooth, periodontal, and oral mucosal status) and collection of saliva samples. Saliva was collected for enzyme-linked immunosorbent assay (ELISA) and was used for determination of sIgA, histatin-5, and lactoperoxidase levels.
Results
Our results showed that adolescents with very high intensity of dental caries (DMF>11) had increased levels of sIgA, histatin-5, and lactoperoxidase compared to adolescents with lower intensity of caries. The increase was statistically significant (p<0.05).
Conclusions
We suggest that high intensity of caries is associated with increased levels of some salivary components – sIgA, histatin-5 and lactoperoxidase – that possess strong bactericidal or bacteriostatic effects, resulting in aggregation of oral bacteria and their clearance from the oral cavity.

Keywords: DMF Index, Adolescent, Dental Caries - enzymology, Histatins - metabolism, Immunoglobulin A, Secretory - metabolism, Lactoperoxidase - metabolism, Saliva - enzymology