Preparation of an Effective Photocure Bonding Agent for Orthodontic Application

Abstract

The purpose of this study is to develop a suitable photocure bonding agent for direct bonding system (DBS) and to show the importance of monomer diffusion into enamel. The photocure adhesive was prepared by mixing monomers and a polymerized reactive organic composite filler (TPMT-filler). The most suitable adhesive was obtained in the 3 wt% HNPM/TEGDMA-TMPT group. The tensile bonding strength to enamel etched with 65 wt% phosphoric acid was 13.1 Mpa and the stability was excellent. SEM examination of the cross-sectional specimens modified with HCl-demineralization suggested that monomer impregantion beyond the etched enamel surface was important for increasing the bonding stability and HNPM was effective to encourage the monomer impregnation.