Bisphenol a Blood and Saliva Levels PRIOR to and after Dental Sealant Placement in Adults: AN Exploratory Study

Placement of dental sealants is an effective therapy for tooth decay prevention. Sealants are formed by reacting glycidyl methacrylate with bisphenol A (BPA). BPA is a hormonally active, synthetic chemical that is part of a broad group of chemicals known as endocrine discrupting compounts, xenoestrogens. Laboratory studies using rodents with BPA exposure as low as 2.5ug/kg body weight/day revealed increased fertility and mammary and prostate cancer. BPA can leach from a dental sealant if not completely polymerized and is released into the oral cavity as a degradation product. This exploratory study examined the presence of BPA in saliva and blood after placement of pit and fissure sealants in 30 subjects, 18-40 years of age, of mixed gender and ethnicity. Differences in bisphenol A comparing low-dose (1-sealant) and high-dose (4-sealants) groups were examined. Data were analyzed using a parametric, two-way analysis of variance for repeated measures. Results reveal presence of bisphenol A one-hour prior to sealant placement in all saliva samples tested. Salivary BPA levels were highest at the one-hour post time period, remained high at the three-hour time period and decreased after 24hrs. Bisphenol A was not detected in serum samples after dental sealant placement. Results for salivary BPA revealed statistically significant differences at all post sealant placement time periods for the high dose sealant group. Further research is needed to examine the cumulative estrogenic effects of BPA from dental sealants.