Bisphenol A Release from Dental Composites and Resin-Modified Glass Ionomers under Two Polymerization Conditions

Bisphenol A (BPA)-based monomers are commonly contained in dental resin-based materials. As BPA is an endocrine disruptor, its long-term release from restorative composites and resin-modified glass ionomers (RM-GICs) under two polymerization conditions was measured in this study. Specimens of two conventional composites containing BPA-based monomers, two BPA-free composites, and two RM-GICs were polymerized from one side for 20 s at 1300 mW/cm(2) or for 5 s at 3000 mW/cm(2). The amounts of BPA released in artificial saliva and methanol after 1, 4, 9, 16, 35, 65, 130, and 260 days were measured using liquid chromatography-tandem mass spectrometry. The highest amounts of BPA were released from conventional composites, followed by RM-GICs, while the least was released from BPA-free composites. Amounts of released BPA were significantly higher in methanol and decreased gradually after the first day. Fast polymerization (5 s at 3000 mW/cm(2)) resulted in a significantly higher release of BPA after 1 day, but the effect of polymerization conditions was not significant overall. In conclusion, fast polymerization increased the initial release of BPA, but the released amounts were significantly lower than the current tolerable daily intake (4 mu g/kg body weight/day) even in methanol, representing the worst-case scenario of BPA release.

Automated summary

This study measured the long-term release of Bisphenol A (BPA) from dental resin-based materials. The results showed that conventional composites released the highest amounts of BPA, while BPA-free composites released the least. Fast polymerization increased the initial release of BPA, but the overall effect of polymerization conditions was not significant.