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Purpose: This multicenter cross‐sectional clinical study aimed to evaluate the membrane perforation rate during transcrestal sinus floor elevation (TSFE) using osseodensification (OD) burs and assess risk factors associated with the procedure. Materials and Methods: This study was conducted in six centers, following ethical standards and approved by local committees. It included patients over 18 years old missing maxillary posterior teeth with crestal residual bone height (RBH) ≥2 and ≤6 mm. Preoperative evaluations were done, including CBCT scans, to assess bone dimensions and sinus health. All centers and surgeons followed a standardized surgical protocol for TSFE using OD burs. Surgical complications, particularly sinus membrane perforations, were recorded and analyzed. Factors such as implant site, premolars or molars, as well as, healed or fresh socket, along with initial RBH were evaluated for their impact on membrane perforation rate. Descriptive statistics, χ2, and logistic regression analysis were used to analyze the data. Results: A total of 621 subjects with an average age of 57.9 years were included. Sinus lifting was performed at 670 sites, with 621 implants placed in the maxilla. The majority of sinus lifts were done in the molar region (76.87%) and in healed bone sites (74.33%). The average RBH was 5.1 mm (ranging from 2 to 7 mm). Sinus membrane perforation occurred in 49 cases (7.31%). RBH ≤3 mm posed a risk factor for sinus membrane perforations followed by RBH >3 and ≤5 mm. Tooth region and implant site were not associated as risk factors for sinus membrane perforation. Conclusion: OD drilling used for TSFE resulted in low membrane perforation rate. Challenging scenarios of severe posterior maxillary atrophy presented as risk factors for increased perforation rate. [ABSTRACT FROM AUTHOR]

Nanostructured Y‐TZP samples with Non‐Homogeneous Yttria Distribution (NNHYD) were prepared by mixing co‐precipitated 3Y‐TZP powder (Tosoh TZ‐3Y) with yttria‐free monoclinic powder (Tosoh TZ‐0), yielding an overall yttria content of 2 mol%. The cyclic fatigue behavior of NNHYD was evaluated by Step‐Stress Accelerated Life Testing (SSALT) and mechanical cycling in a biaxial flexural strength test (BFST) setup and compared to Conventional Submicrometric 3Y‐TZP (CS). Physical, structural, microstructural, and mechanical characterizations of all groups were also evaluated and compared before and after artificial aging in autoclave. NNHYD presented a higher capacity for damage accumulation and maintenance of phase transformation potential than CS, associated with elevated resistance to the propagation of Low‐Temperature Degradation (LTD). A nanostructured 3Y‐TZP surface layer introduced in NNHYD by dip coating (DC‐NNHYD) improved resistance to LTD at the cost of reduced reliability under cyclic fatigue by increasing the stability of the tetragonal phase. This surface alteration highlights the impact of surface properties on mechanical performance. The results of this study present practical possibilities to help achieve the ideal balance between strength, toughness, and LTD resistance to improve the lifetime of zirconia‐based biomaterials. [ABSTRACT FROM AUTHOR]

A technique is outlined for utilising a polymeric composite reinforced with glass fibres in a three-dimensional mesh as a post-core in aesthetic cases. The clinical procedure involves obtaining an impression of the root canal space, scanning the definitive cast, and milling a fibre-reinforced composite post-core. Subsequently, the intra-radicular post-core is cemented using an adhesive resin cement. The use of custom-made computer-aided design–computer-aided manufacturing (CAD-CAM) fibre-reinforced composite post-core facilitates repairability, provides better adaptation to the root canal space, avoids uneven cement thickness, ensures chemical adhesion to resin cement, and promotes favourable aesthetics when combined with all-ceramic crowns. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of two finishing techniques, glazing or polishing, in comparison with the as‐cut condition, on the biaxial‐flexural‐strength (BFS) of a zirconia‐reinforced lithium silicate ceramic (ZLS). Cylinders were milled from CAD/CAM blocks and sliced to obtain disc‐shaped specimens (ISO6872:2015). Polished and glazed specimens were processed following the manufacturer's instructions. Thirty‐three specimens were obtained for each condition and microstructural and BFS/fractographic characterizations were performed. BFS and roughness data were analyzed using Weibull statistics and ANOVA one‐way with Tukey post‐hoc test, respectively. While a rougher surface was observed for as‐cut specimens, smoother surfaces were observed for polished and glazed ZLS at microscopical evaluation and confirmed through surface‐roughness evaluation. X‐ray spectra depicted a glass phase for all groups and characteristic metasilicate, lithium disilicate, and lithium phosphate peaks for the as‐cut and polished specimens. Glazed specimens showed higher characteristic strength than polished and as‐cut specimens, which did not differ significantly. While higher Weibull‐modulus was observed for the polished than for the as‐cut specimens, no statistically significant differences were noted between glazed and polished, and between glazed and as‐cut specimens. ZLS presents higher strength when glazed, and polishing increases the structural reliability of the material relative to the as‐cut condition. Both finishing techniques reduced surface roughness similarly. [ABSTRACT FROM AUTHOR]

Statement of Problem: The tapered interference fit (TIF) implant system, a screwless system with purely frictional retention, was developed to minimize prosthetic complications associated with screw loosening. However, evidence regarding its biomechanical behavior is scarce., Purpose: The purpose of this in vitro study was to compare the reliability, failure mode, and stress distribution of frictional TIF implant systems with straight and custom in-office angled abutments and conventional taper integrated screw-in (TIS) systems., Material and Methods: One hundred and five implants with single crowns were divided into 5 groups (n=21) according to the type of retention (TIF or TIS) and angulation of the abutment, straight (S) or angled (A): straight universal abutment (TIF); 17-degree angled abutment (TIF-A); straight universal abutment (TIS); 17-degree angled abutment (TIS-A); and straight abutment with passing screw (TIS-P). The reliability was assessed by step-stress accelerated life testing (SSALT) (n=21). The failure mode was investigated using fractographic analysis. Finite element analysis (FEA) was performed to analyze stress distribution. The von Mises stress (σvM) and displacement were assessed for implant and abutment, while shear stress (τmax) and minimum principal stress (σmin) were evaluated for cortical and cancellous bone., Results: All groups presented high reliability at a load of 100 N. The TIS-P (93%) showed lower reliability than the TIF and TIS-A (99%) groups. However, with the increase of load to 150 N, the reliability of the TIS (60%), TIS-P (82%), and TIF-A (81%) groups decreased. No changes were observed for TIF and TIS-A. All specimens failed by fracture after SSALT, with failures restricted to the transmucosal area of the abutment. FEA showed an increase in σvM of at least 60% in the abutment for the TIF groups, while a reduction of 64% was observed in the implant. The displacement was greater for TIF (54.36 mm) in the abutment and higher for TIS-P (6.97 µm) in the implant. Also, the TIF and TIF-A groups exhibited better cortical and cancellous bone stress distribution., Conclusions: The TIF systems can be safely indicated for implant-supported prostheses in the anterior region because of their high reliability and excellent stress distribution to the bone. Custom in-office angulation may decrease reliability, suggesting a preference TIS systems., (Copyright © 2025 Editorial Council for The Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

This study evaluated the development and characterization of alumina-toughened zirconia (ATZ) composites containing 10 wt% Al 2 O 3 whiskers subjected to the glass infiltration. To obtain ATZ 90/10 composites, the commercial 3Y-TZP powder was mixed with synthesized alumina whiskers and subsequently compacted. Discs (n = 210) were pre-sintered at 1000 °C for 1 h. The infiltration of glass (68SiO 2 -11.7Al 2 O 3 -3CaO-7.3Na 2 O-10K 2 O) was developed by mixing glass and propylene glycol, which was then applied onto ATZ pre-sintered specimens. For infiltration, the graded discs were divided into two different sintering protocols: protocol 1 (1550 °C for 2 h) and protocol 2 (1350 °C for 1 h followed by 1550 °C for 2 h). As a control group, non-infiltrated specimens were sintered using protocol 1. The specimens were characterized by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), and Raman spectroscopy. Hardness, fracture toughness, and biaxial flexural strength tests followed by fractographic analysis were performed. Statistical analyses were conducted using Weibull distribution to calculate the material's modulus (m) and characteristic strength (95% CI), as well as ANOVA tests. High-aspect ratio alumina whiskers (10 μm × 200 nm) were synthesized. While the control group's XRD patterns evidenced only characteristic tetragonal zirconia and α-alumina peaks, the glass-infiltrated groups did not present characteristic peaks of crystalline materials. ATZ with alumina whiskers showed higher fracture toughness and characteristic strength compared to conventional ATZ. Furthermore, glass-infiltration improved the characteristic strength of conventional ATZ with no significant differences observed in the Weibull modulus. For W-G-2, C, and W groups the fractures originated at the zirconia surface, while for C-G-1-, C-G-2, and W-G-1 the origins were inside the ceramic microstructure. In conclusion, the development of ATZ with alumina whiskers increased the biaxial flexural strength and fracture toughness compared to conventional ATZ. The glass gradation significantly improved the characteristic strength of conventional ATZ regardless of the sintering protocol used, whereas it only improved the characteristic strength of whisker-reinforced ATZ when a single sintering was performed. Additionally, the sintering protocol influenced the thickness and amount of glass gradation in the composites., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025. Published by Elsevier Ltd.)

This study evaluated the survival probabilities of two lithia-based glass-ceramics after final crystallization in a microwave furnace using conventional crystallization as a reference. Disc-shaped samples of a lithium silicate (LS, Celtra Duo) and a lithium disilicate (LD, e.max CAD) were prepared and divided into two groups according to the crystallization method (n = 30): microwave (M) or conventional furnaces (C). The biaxial flexural strength test was used to determine the fatigue test profile and its parameters. Then, specimens were submitted to an accelerated life test (step stress) using three profile levels - mild, moderate, and aggressive - varying the load increments and the number of cycles until fracture (4 Hz). Survival data were used to calculate Weibull's beta (β) value and reliability of the assigned missions. Scanning electron microscopy was employed to analyze surface morphology, fracture characteristics, and failure patterns. Beta (β) values for the LS-C, LS-M, LD-C, and LD-M groups were 2.65, 0.25, 0.62, and 0.3, respectively. Similar reliability was observed in all groups after 50,000 cycles at 100 and 150 Mpa. At 200 Mpa, the crystallization method did not affect the reliability within LS or LD. However, LD showed greater reliability than LS when crystallized by microwave energy. Thus, microwave energy can be suggested as an alternative to the process of conventional lithia-based glass-ceramics crystallization without damaging their survival probabilities.