Wear behavior of materials for fixed dental prostheses

PURPOSE: This study evaluated the wear behavior of dental materials for definitive fixed prostheses, including computer-aided design (CAD)- and manufacturing (CAM) composite resins, polyether-ether-ketone (PEEK), Ag-Pd-Au alloys, titanium, and zirconia, under standardized experimental conditions. METHODS: Three CAD-CAM-produced composite resins (HC, HCH, and CS), PEEK (SPE), Ag-Pd-Au alloys (CW), pure titanium class II (TJ), and zirconia (ZL) were tested. Two-body wear tests were conducted using an abrasion-testing machine under wet conditions using stainless-steel styluses as antagonists. Wear traces were examined using laser confocal scanning microscopy and scanning electron microscopy (SEM). Wear depths and heights were analyzed by one-way analysis of variance with Tukey's multiple comparison test. RESULTS: The wear depths of CS and TJ were significantly greater than those of the other materials (P < 0.05), whereas ZL exhibited the lowest wear depth. No significant differences were found among HC, HCH, SPE, and CW. The stylus opposing the SPE exhibited the smallest wear height, whereas TJ caused the most antagonist wear. SEM revealed distinct wear mechanisms, including adhesive and abrasive wear, depending on the material. CONCLUSIONS: The SPE and CW showed similar wear behavior. CAD/CAM composite resins demonstrated variable wear rates, which was likely attributable to variations in the composition and morphology of the constituent fillers. The TJ exhibited excessive antagonist wear, suggesting the need for improved tribological properties. These findings provide guidance for selecting materials that preserve occlusion and prevent excessive wear.