Restoration-enamel interface with argon laser and visible light polymerization of compomer and composite resin restorations: a polarized light and scanning electron microscopic in vitro study

This polarized light (PL) and scanning electron microscopic (SEM) in vitro study investigated the effect of argon laser (AL) and visible light (VL) polymerization on the interfaces between compomer and composite resin restorations and the enamel cavosurfaces. Surface topography by SEM revealed a smooth transition between the restorative materials and adjacent enamel surfaces with no microspaces between the restorations and enamel surfaces. The enamel surfaces showed relatively smooth surface coatings with AL curing compared with exposure of etched prism endings with VL curing. The restoration-enamel interface by PL showed an intimate relationship between the restorative materials and the cavosurface enamel. No differences were found between AL and VL polymerization. With the restoration-enamel interface by SEM, compomers and composite resins were adapted closely to the cavosurface enamel and tags of restorative material protruded into the adjacent cavosurface enamel. Both VL and AL polymerization of compomers and composite resin restorations in vitro produced closely adapted restorations with intimate restoration-enamel interfaces. Such restoration-enamel interfaces may provide a certain degree of resistance against secondary caries formation, and this may be enhanced by the caries protective effect of argon laser irradiation.