Abstract
The purpose of this study was to compare the properties of trial hard resin teeth with an enamel layer made of nanocomposite to those of conventional hard resin teeth. Mechanical properties such as flexure strength, compressive strength and hardness of the nanocomposite were significantly greater than those of the enamel layer of conventional hard resin teeth. However, because of a lack of staining resistance, about 10 wt% poylmethyl methacrylate(PMMA) powder was added to the nanocomposite. The enamel layer containing PMMA powder was inferior to that of the conventional hard resin teeth in mechanical properties. Surface roughness of the trial hard resin teeth after the abrasion test was significantly less than that of the conventional hard resin teeth. Furthermore, the plastic rod used for the abrasion test of the trial hard resin teeth showed significantly less abrasion loss than the conventional hard resin teeth. The reduced surface roughness and abrasion loss may decrease negative effects on antagonistic teeth in clinical use. The trial hard resin exhibited significantly better transparency and staining resistance than the conventional hard resin teeth. This can be explained by the features of the nanocomposite in which nanoparticles are uniformly distributed.
