Salivary blood group antigens and microbial flora.

OBJECTIVE: Secretor is an individual with ability to produce blood group reactive substances in the exocrine glands and to secrete these substances in the body fluids such as saliva. In saliva the blood reactive antigens are found primarily on mucins which exhibit microheterogenicity and different subtypes of these molecules. This study was done to find out if the salivary blood group antigens have any role in the adherence of certain selected microorganism in the oral cavity.

METHODS: Unstimulated whole saliva and sub gingival plaque samples were collected from subjects with clinically healthy gingival, chronic gingivitis and chronic periodontitis with probing pocket depth ≥4mm and attachment loss ≥1mm. Secretor status was determined by using Haemagglutination Inhibition Assay. Unstimulated whole saliva and sub gingival plaque samples were collected to culture and isolate the selected microorganisms. The clinical scores, secretor status and the presence or absence of selected microorganisms were compared within the groups using Chi-square test and students unpaired t-test.

RESULTS: The numbers of secretors were more in the healthy group (22.2%) and non secretors were more in the chronic periodontitis group (22.2%). The clinical scores were higher in the in non secretors compared to the secretors in all the three groups. P intermedia and P gingivalis were prevalent among non secretors in chronic gingivitis group. (P=0.075 and P=0.032) and chronic periodontitis group (P=0.068 and P=0.009).