Mineralization of Resin Using Experimental Adhesives Containing Hydroxyapatite in Long Term

Abstract

Incomplete resin infiltration into acid-etched dentin leaves water-rich, resin-poor regions in hybrid layers that may cause degradation of resins and collagen fibrils. Incorporation of hydroxyapatite (HAp) into resins may provide a reservoir of calcium phosphate that might "backfill" water-filled voids in hybrid layers and resins. The purpose of this study was to test the hypothesis that incorporation of HAp into experimental resins can fill in microvoids with calcium phosphate. Three experimental adhesives were created by adding 0, 5 or 10wt% HAp. We carried out the following experiments: Water sorption and solubility evaluation, Evaluation of the calcium deposition inducibility, SEM observation and energy dispersive X-ray analysis, Tensile Testing. Although hydroxyapatite appears to have no effect on the ability of resin to infiltrate dentin in this study, incorporating HAp into dental adhesives may allow the formation of crystals below the hybrid layer, which could help create a stronger anchor.