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Purpose To determine if surface treatment and cement selection for traditional 3 mol% yttria partially stabilized zirconia (3Y‐PSZ), “translucent” 5 mol% yttria‐stabilized zirconia (5Y‐Z), or lithium disilicate crowns affected their fracture load. Materials and Methods Crowns with 0.8 mm uniform thickness (96, n = 8/group) were milled of 3Y‐PSZ (Lava Plus), 5Y‐Z (Lava Esthetic), or lithium disilicate (e.max CAD) and sintered/crystallized. Half the crowns were either particle‐abraded with 30 µm alumina (zirconias) or etched with 5% hydrofluoric acid (lithium disilicate), and the other half received no surface treatment. Half the crowns from each group were luted with resin‐modified glass ionomer (RMGI, RelyX Luting Plus) and half were luted with a resin cement (RelyX Unicem 2) to resin composite dies. Crowns were load cycled (100,000 cycles, 100 N force, 24°C water) and then loaded with a steel indenter until failure. A three‐way ANOVA examined the effects of material, cement, and surface treatment on fracture load. Post‐hoc comparisons were performed with the Tukey‐Krammer method. Results Fracture load was signficiantly different for materials and cements (p < 0.0001) but not surface treatments (p = 0.77). All lithium disilicate crowns luted with RMGI failed in fatigue loading cycling; 3Y‐PSZ and 5Y‐Z crowns luted with resin showed a higher fracture load compared with RMGI (p < 0.001). With resin cement, there was no signficant difference in fracture load between 5Y‐Z and lithium disiliciate (p = 1) whereas 3Y‐PSZ had a higher fracture load (p < 0.0001). Conclusions Cement type affected fracture load of crowns but surface treatment did not. The 0.8 mm uniform thick crowns tested benefited from using resin cement regardless of type of ceramic material. Crowns fabricated from 5Y‐Z may be particle‐abraded if luted with resin cement.

Within the limitations of this study, tilting the implant apex to the lingual significantly reduced the fracture strength of angle-corrected zirconia abutments. Accordingly, while the angle between the occlusal force application and the long axis of the implant decreases, the resistance (force) to fracture decreases.

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A patient presenting with severe microstomia (PDI Class IV) was unable to insert a maxillary complete denture. Sectional final impressions were made using two impression materials and an interlocking custom tray. A folding record base was used for maxillomandibular relationship records. A novel folding maxillary denture with a custom hinge and plunger attachment to lock the denture in the open position was fabricated. The patient was able to insert the collapsed denture, open it intraorally, and enjoy successful masticatory function.

Purpose Candida albicans has been regarded as the most predominant oral fungal pathogen and the main cause of denture stomatitis. This study aimed to investigate C. albicans adherence to three types of denture base polymers: heat‐cured polymethylmethacrylate (PMMA), CAD‐CAM milled and 3D‐printed. The efficacy of four common disinfection techniques, glutaraldehyde, brushing, microwave irradiation, and Polident overnight tablets, were also examined. Material and methods Sixty blocks of pink acrylic specimens were fabricated from each polymer group. To investigate the C. albicans adherence, as well as the efficacy of different disinfection techniques on removing the yeast from the different materials, specimens were cultured within the fungal culture overnight followed by disinfection. The adhered C. albicans on the materials were then obtained by vortexing in phosphate buffered saline (PBS), and the numbers of the yeast in the suspensions were evaluated by measuring the optical density and/or colony‐forming units on agar plates. Data were expressed as mean ± SEM (standard error of the mean). Statistical differences were evaluated by one‐way analysis of variance (ANOVA) followed by the post hoc Tukey HSD tests. Results Significant differences in C. albicans adherence to the three polymers were noted. CAD‐CAM milled and heat‐cured PMMA showed significantly less C. albicans adherence compared with 3D printed PMMA. No significant difference was noted between milled and heat‐cured PMMA. In the disinfection test, microwave irradiation, mechanical brushing, and Polident tablets were found to be effective in removing fungal attachment on the different denture materials, while glutaraldehyde was found to be the least effective. Conclusion C. albicans adherence to the polymers varies greatly based on the types of PMMA. 3D‐printed had the highest fungal biofilm attachment. Microwave irradiation, mechanical brushing, and Polident overnight tablets had comparable results in removing C. albicans from all types of PMMA, while glutaraldehyde was not as effective.