Analysis of Bisphenol A Released From Resin-Based Dental Sealants

Objectives: Dental sealants are used successfully to prevent occlusal caries. Resin-based sealants using bisphenol A glycidyl methacrylate (bis-GMA) contain bisphenol A (BPA) as an unreacted monomer from the manufacturing process. A variety of adverse effects are associated with exposure to BPA. The US Environmental Protection Agency (EPA) established an exposure level of 50,000ng/kg body weight/day. The objective of this study was to evaluate BPA content of dental sealants available in the US market.
Methods: 12 dental sealants purchased through distributors were analyzed for BPA content to assess any hazardous levels. Samples were formed and weighed using Teflon molds with a 10-mm diameter and 2-mm depth. Polymerization followed manufacturers’ instructions. Extraction of polymerized (24h) and unpolymerized (48h) samples was in artificial saliva or acetonitrile at 37 C° (72 samples,n=3). Samples were cured using an Optilux 501(Kerr) with light radiant emittance of >600mW/cm². Extracts were analyzed using LC-MS/MS with a ≤0.5ng/mL detection limit.
Results: Of the 12 polymerized sealants analyzed at 24h in artificial saliva, one group(8.3%) had BPA levels below the quantification limit (BQL), six groups(50%) had BPA levels ≤0.1ng, four groups(33.3%) were between 0.1Conclusions: BPA exposure from these dental sealants is well below the daily exposure level set by the EPA and can be considered safe.