In vitro assessment of fracture resistance of premolar teeth restored with diatomite zirconia versus barium glass filled resin composite.

Evaluate the fracture resistance of premolar teeth with MOD cavities restored with Diatomite Zirconia/Silica Filled Resin Composite Versus Barium Glass/Yetterbium Fluoride Filled resin composite systems. A 40 maxillary premolar were divided equally into four main groups (10 teeth each); a positive control group of unprepared teeth and a negative control group with prepared and unrestored MOD cavity. While the two other restored groups in which teeth with prepared MOD cavities were restored either with Diatomite Zirconia/Silica Filled Resin Composite (Zircon Fill composite, ZF) or Barium Glass/Yetterbium Fluoride Filled resin composite (Neo Spectra Composite, NS). A standardized MOD cavity was prepared in premolar teeth. Teeth were restored according to the corresponding group, and then exposed to thermocycling prior fracture resistance tested. Data collected from fracture resistance and failure mode were collected and statistically analyzed with ANOVA test. The significance level was set at p < 0.05 within all tests. There was a significant difference between different tested groups, with prepared teeth having significantly lower fracture resistance than sound teeth and samples restored with both restorative materials (p < 0.001). For Neo Spectra, most samples had mixed while Zirconfil were either had adhesive or cohesive failures with no statistically significant difference (p = 0.077). All the associations between fracture resistance and failure modes were not statistically significant. The two tested resin composites exhibited similar fracture resistance to each other and to sound teeth. Diatomite Zirconia/Silica Filled Resin Composite versus Barium Glass/Yetterbium Fluoride Filled resin composite systems were able to reinforce and restore the strength properties of the tooth.