Evaluation of monomer leaching from a resin cement through dentin by a novel model

To evaluate the elution of HEMA, BPA, UDMA and BisGMA from a conventional resin cement (Multilink Automix^®, Ivoclar Vivadent) through human dentin, under constant positive pulpal pressure.

Ten human dentin disks (n=10) were adjusted in a new testing device and transparent glass slabs were luted with Multilink Automix^® resin cement, following manufacturer's instructions, under a steady pressure of 25N. The device was filled with Ringer's solution. At 5min, 20min, 1h, 2h, 21h, 3 days, 7 days, 10days and 21days time intervals, the whole eluate was retrieved from each one of the ten specimens and then, the specimens were refilled with fresh Ringer's solution. The eluates were analyzed by High Performance Liquid Chromatography (HPLC).

HEMA was detected in the eluate of all of the specimens, from 5min until 10 days. At four of the specimens, HEMA was also detected in the 21days eluate at very low concentrations. BPA, UDMA and BisGMA were not detected at any eluate. An unknown compound was also detected at 4.4min.

The concentrations of HEMA that enabled to diffuse from Multilink Automix^® cement in an aqueous solution, through a dentin barrier, did not reach toxic levels and BPA, UDMA and BisGMA were not detected at all.