Objective. The wear behavior of the novel zirconia generation is less well understood and may be affected by compositional modifications compared to the conventional zirconia. Materials and Methods. Combinations of keywords such as “zirconia,” “high translucent,” and “wear” were searched in PubMed and Google Scholar databases up to May 2021. The total of 23 relevant articles was selected according to inclusion criteria. Results. Reports show comparable wear resistance of translucent zirconia to the conventional zirconia despite an increased cubic phase content and lower mean flexural strength. A meticulously polished surface creates the lowest surface roughness, producing favorable zirconia wear resistance and antagonist wear compared to a glazed surface. In comparison to other ceramic materials, zirconia produces the least wear on an enamel antagonist and almost undetectable wear when opposed by zirconia. Wear when paired against resin materials yields a favorable outcome, whereas wear behavior against a metal antagonist varies with the surface hardness of the metal. Conclusions. All zirconia generations are considered wear‐friendly to all types of antagonists. Nonetheless, comparative studies on antagonist wear opposing zirconia of different compositions are still limited and further investigation is required.

Purpose. To investigate effects of number and location on patterns of von Mises stress distribution and volume average stress on abutment tooth, edentulous ridge, mini dental implant, and surrounding bone of mini dental implant‐assisted mandibular Kennedy class I removable partial denture. Materials and Methods. Eight three‐dimensional finite element models of mandibular Kennedy class I with different numbers and locations of mini dental implants were constructed. Mini dental implants were generated in the area of second premolar, first molar, and second molar, respectively. A static load of 400 N was applied on all models. The von Mises stress and volumetric average stress were calculated by three‐dimensional finite element analysis. Result. The minimum volumetric average stress of abutment tooth was found in the model, where there was one mini dental implant at the second molar position and 2 mini dental implants at first molar and second molar positions. The model with three mini dental implants had reduced volumetric average stress of abutment tooth, which was not different from the model with two mini dental implants. However, the minimum volumetric average stress of mini dental implant and surrounding bone were found when three mini dental implants were applied, followed by two and one mini dental implants, respectively. Conclusion. Placing at least one mini dental implant at a second molar position can help reduce stress transferred to the abutment tooth. Stresses around each implant and surrounding bone reduced with increased numbers of mini dental implants.

Objective Despite the emergence of numerous three-dimensional (3D) printed provisional resin, there are no conclusive guidelines for repairing them. This study aims to investigate the effects of different repair materials and surface treatments on the shear bond strength of 3D-printed provisional resin. Materials and Methods A total of 180 3D-printed resin specimens underwent six surface treatments: no surface treatment (control), silicon carbide paper (SP), sandblasting with aluminum oxide (SB), SP followed by SB (SP + SB), SP with bonding agent (SP + BD), and SB with bonding agent (SB + BD). Each group was repaired with polymethyl methacrylate (PMMA), Bis-acryl, and flowable composite resin (FCR). The shear bond strength of the bonded specimens was tested using a universal testing machine and the mode of failure was examined with stereomicroscope. Statistical Analysis The Shapiro–Wilk test was used to assess normal distribution, and two-way analysis of variance (ANOVA; α = 0.05) was used to find the effect of independent variables on the shear bond strength. The post hoc test was achieved using the Tukey honest significant difference (HSD) test. Results Two-way ANOVA indicated a statistically significant interaction between repair materials and surface treatments in relation to the shear bond strength of 3D-printed resin (p < 0.001). The three highest shear bond strengths overall were SB repaired with Bis-acryl (17.30 ± 0.77 MPa), SB + BD repaired with FCR (17.20 ± 0.29 MPa), and SB + BD repaired with PMMA (16.60 ± 0.71 MPa), which were significantly higher than their control group (p < 0.001). However, there were no significant differences between these groups. Notably the lowest shear bond strength in PMMA occurred in the control group (8.49 ± 0.42 MPa), while the lowest shear bond strength in Bis-acryl and FCR was observed in the SP group (7.28 ± 0.71 and 8.84 ± 1.15 MPa, respectively). Conclusion Repair materials and surface treatments play an important role in repairing 3D-printed resin. PMMA and composite resin–based repair materials require both sandblast and a chemical bonding agent, while Bis-acryl-based repair materials only need sandblasting to improve the shear bond strength.