Targeted Compounds Released from Resin-Based Dental Materials

Resin based materials are increasingly been used and their safety is assumed. However, these materials contain a number of different compounds some of which may be released into aqueous solutions and could have an adverse effect. Objectives: To investigate, in vitro, the elution of targeted compounds from 4 materials, into different solutions. Targeted constituents investigated were HEMA, TEGDMA, Bisphenol-A (BPA), Dibutyl phthalate (DBP), dicyclohexyl phthalate (DHP) and Di-2-ethylhexyl phthalate (DEHP). Methods: Resin based materials Z100, Kent Dental Composite (KD) and Compoglass flow (CF) along with a conventional glass-ionomer, KetacFil (KF), were investigated. Three standardised discs of each material were immersed in either 3ml of distilled water or 3ml of a 75% ethanol solution and transferred into fresh solution at 3hrs, 24hrs, 3days, 7, 14 and 28 days. Analysis of the solutions occurred using reverse phase chromatography with a Dionex modular HPLC system. Calibration curves were created using commercial standards of components examined. Results: The release of components was clearly different in the 2 solutions with the ethanol solution being more aggressive. Also there were differences between the resin-based materials (Z, KD, CF) and the glass ionomer material (KF). In ethanol solutions, TEGDMA was consistently released from the resin based materials only. Phthalate compounds, particularly DBP, were also occasionally noted from the resin based materials, although the amount released was very small. CF appeared to release very small amounts of BPA. A number of unknown peaks were noted from all of the resin based materials. Monomer levels released into distilled water were invariably less than into ethanol solution, with the exception of TEGDMA which was similar in both solutions. No phthalates were found released into distilled water. Conclusions: The present study suggested that certain compounds could be released from these materials. However, the effect of these compounds is not yet known.