Estrogenicity of resin-based composites and sealants used in dentistry

We tested some resin-based composites used in dentistry for their estrogenic activity. A sealant based on bisphenol-A diglycidylether methacrylate (bis-GMA) increased cell yields, progesterone receptor expression, and pS2 secretion in human estrogen-target, serum-sensitive MCF7 breast cancer cells. Estrogenicity was due to bisphenol-A and bisphenol-A dimethacrylate, monomers found in the base paste of the dental sealant and identified by mass spectrometry. Samples of saliva from 18 subjects treated with 50 mg of a bis-GMA-based sealant applied on their molars were collected 1 hr before and after treatment. Bisphenol-A (range 90-931 micrograms) was identified only in saliva collected during a 1-hr period after treatment. The use of bis-GMA-based resins in dentistry, and particularly the use of sealants in children, appears to contribute to human exposure to xenoestrogens.This work was supported by grant 94/1551 from the Fondo de Investigaciones Sanitarias (FIS), the Spanish Ministry of Health and the Consejeria de Salud, Junta de Andalucía (to N.O.), National Institutes of Health grant CA13410 (to C.S.), CA55574, and NSF-DCB-105594 (to A.M.S.)