Load bearing capacity of fiber-reinforced and unreinforced composite resin CAD/CAM-fabricated fixed dental prostheses.

It is unclear if fiber-reinforced fixed dental prostheses can be fabricated with physical properties that make them suitable for definitive prostheses. The purpose of this study was to compare the load bearing capacity of fiber-reinforced and unreinforced computer-aided design/computer-aided manufacturing (CAD/CAM) fabricated fixed dental prostheses. Fixed dental prostheses were fabricated with CAD/CAM from 3 experimental fiber-reinforced composite resin blocks, 1 experimental composite resin block, and 1 commercially available composite resin block. The experimental fiber-reinforced composite resin was prepared by mixing dimethacrylate resin with filler particles of BaO silicate and E-glass fiber. Different ratios of resin, filler, and fiber were used to fabricate specimens measuring 15.5 × 19 × 39 mm, which were allocated to 5 different groups (n=8) and statically loaded until final fracture. Statistical analyses were calculated according to final fracture values. A 1-way ANOVA and the Tukey post hoc multiple comparison test were used (α=.05). All groups showed significantly different load-bearing capacities (P<.001). Experimental randomly oriented fiber-reinforced composite resin blocks revealed the highest load-bearing capacity (2163 ±246 N), whereas commercial composite resin blocks showed the lowest (1290 ±172 N). Fixed partial dental prostheses consisting of experimental fiber-reinforced composite resin blocks showed higher load-bearing capacities than did unreinforced composite resin blocks.