Exposure to bisphenol A from bis-glycidyl dimethacrylate-based dental sealants

Background. Bisphenol A (BPA) is a common component of composites and dental sealants. The potential exists for human-exposure after sealant placement. Methods. The authors prospectively enrolled 15 men in an exposure assessment study; 14 completed the study. After placement of clinically appropriate amounts of one of two sealants, the authors measured BPA in saliva and urine samples collected at prescribed intervals after the sealants were placed. They used selective and sensitive isotope-dilution mass-spectrometry-based methods for BPA measurements, thus providing the most reliable results. Results. Helioseal F (Ivoclar Vivadent, Amherst, N.Y.) leached negligible amounts of BPA. Urinary and salivary BPA levels in subjects who received these sealants were similar to baseline levels. Delton Light Cure (LC) Opaque pit-and-fissure sealant (Dentsply/Ash, York, Pa.) leached more BPA, resulting in low-level BPA exposures similar to those used in laboratory animal testing. BPA exposure after Delton LC sealant placement was significantly higher than exposure after placement of Helioseal F. Patients treated with Delton LC had significantly higher doses of BPA (110 mu g) than did those treated with Helioseal F (5.5 mu g) (P < .0001). Conclusions. Placement of clinically relevant amounts of Delton LC sealant resulted in low-level BPA exposure; however, exposure was negligible after placement of Helioseal F. Saliva collection after sealant placement likely reduced systemic absorption of BPA from dental sealants. Sealants should remain a useful part of routine preventive dental practice, especially those that leach negligible amounts of BPA. Clinical Implications. Dental sealants may be a point source for low-level BPA exposure at levels that show health effects in rodents. Further research is required to determine whether human exposure to BPA at these levels causes adverse effects.