The Relationship between Salivary and Serum IgA and IgG Levels and Dental Caries in Adults

BACKGROUND Dental caries is one of the most common microbial infectious diseases. The important method for as-sessment of oral health status is DMFT (Decayed, Missing, and Filled Teeth). Recent studies have shown conflicting results regarding the relationship of antibodies with dental caries. This study aimed to investigate the salivary and serum IgA and IgG levels in adult caries. METHODS This cross-sectional study was conducted on 96 patients with dental caries who were referred to the specialized dental clinic in Yasuj. Based on the DMFT index, patients were divided into three groups. DMFT index in group 1, 2, and 3 were 0, 1 - 3, and more than 3, respectively. Salivary and serum levels of IgA and IgG were measured by nephelometric method. Data were analyzed using SPSS software, chisquared, and paired t-test. RESULTS The mean salivary IgA level in group 1, 2, and 3 were 0.259 ± 0.118, 0.264 ± 0.175, and 0.169 ± 0.106 mg%, respectively (p = 0.001). Also, the mean salivary IgG level in group 1, 2, and 3 were 1.360 ± 316, 1.320 ± 0.350 and 1.320 ± 0.370 mg% (p = 0.929). The mean serum IgA level were 1.443 ± 0.433, 1.805 ± 0.518 and 1.790 ± 0.700 gr% in group 1, 2 and 3, respectively (p = 0.363). Also, the mean serum IgG level in group 1, 2, and 3 were 9.275 ± 1.899, 10.257 ± 1.658 and 10.589 ± 3.113 gr% (p = 0.451). CONCLUSIONS This study showed that by decreasing the level of salivary IgA, the rate of dental caries and DMFT index increase and this indicates the protection mechanism against dental caries by IgA.