Abstract
The purpose of this study was to elucidate whether the hepatitis B virus infection of practicing dentists occurrs through saliva. I investigated the mechanism of HBs antigen occurrence in saliva and the possibility of contamination from saliva containing by hepatitis B virus during dental treatments.
1. From the analysis of the relationship between the amount of HBs antigen in serum and saliva and the amount of occult blood in saliva in HBV carriers, I found that the HBs antigen found in saliva might come from direct contamination by blood. Therefore, the amount of HBs antigen in saliva can be estimated by the amount of occult blood.
2. The occult blood was measured with Hemastix in 245 cases of general dental treatment. Bleeding was found to increase more than 90% in cases of tooth extraction, scaling, and crown & bridge preparation. These cases gave a veading of more than positive “+++” in the Hemastix test.
The results suggested the possibility that minimum infective dose (according animal experiments) was released into the mouth as HBs antigen. This comfirmed the possibility that practicing dentists are exposed to danger of infection with HBV through the HBV carriers' saliva.
It might be possible to decrease the efficacy of hepatitis B virus by frequent washing of the oral cavity during dental treatments.
