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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]

Peri-implant infections, in the absence of adequate treatment, can finally lead to premature loss of the implant. Among targeted protocols recently proposed for the treatment of peri-implant bone defects, and in the case of short implants, reconstructive surgery represents a recommended option. The purpose of this study was to evaluate the outcomes, in terms of maintenance, of a reconstructive treatment for peri-implantitis in locking-taper plateau-design single-crown implants, followed for 5 years after surgery. A retrospective evaluation was conducted in 20 patients treated with access flap surgery, concomitant chemical and mechanical surface decontamination, and bone grafting (using a self-hardening mixture of bone substitutes and biphasic calcium sulfate without the use of membranes). Of the 21 implants assessed, 9 were 8 mm-length, and 12 were 6 mm-length. Implant loss and treatment success were, respectively, 0% and 80.95% after 5 years from surgery. All parameters related to bone levels and soft tissue conditions significantly improved after 3 years and remained stable at the 5-year follow-up. The proposed protocol, followed by an effective supporting periodontal therapy, demonstrated the maintenance of the function of all implants, providing adequate stability during the healing process after surgery and limiting the onset of disease recurrence. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate and compare the reliability of implant-supported single crowns cemented onto abutments retained with coated (C) or noncoated (NC) screws and onto platform-switched abutments with coated screws. Materials and Methods: Fifty-four implants (DT Implant 4-mm Standard Platform, Intra-Lock International) were divided into three groups (n = 18 each) as follows: matching-platform abutments secured with noncoated abutment screws (MNC); matching-platform abutments tightened with coated abutment screws (MC); and switched-platform abutments secured with coated abutment screws (SC). Screws were characterized by scanning electron microscopy and x-ray photoelectron spectroscopy (XPS). The specimens were subjected to step-stress accelerated life testing. Use-level probability Weibull curves and reliability for 100,000 cycles at 200 N and 300 N (90% two-sided confidence intervals) were calculated. Polarized light and scanning electron microscopes were used for fractographic analysis. Results: Scanning electron microscopy revealed differences in surface texture; noncoated screws presented the typical machining grooves texture, whereas coated screws presented a plastically deformed surface layer. XPS revealed the same base components for both screws, with the exception of higher degrees of silicon in the SiO2 form for the coated samples. For 100,000 cycles at 300 N, reliability values were 0.06 (0.01 to 0.16), 0.25 (0.09 to 0.45), and 0.25 (0.08 to 0.45), for MNC, MC, and SC, respectively. The most common failure mechanism for MNC was fracture of the abutment screw, followed by bending, or its fracture, along with fracture of the abutment or implant. Coated abutment screws most commonly fractured along with the abutment, irrespective of abutment type. Conclusion: Reliability was higher for both groups with the coated screw than with the uncoated screw. Failure modes differed between coated and uncoated groups. [ABSTRACT FROM AUTHOR]

Aims: To address the two following questions: (1) What kind of somatosensory abnormalities may be characterized in patients receiving dental implants (IMP), in ongoing inflammatory dental pulpitis (IP) patients, and in neuropathic pain (atypical odontalgia [AO]) patients? and (2) What sort of sensory and neural changes may result from dental implant placement surgery and pulpectomy? Methods: A total of 60 subjects were divided into three groups: the IMP (n = 20), IP (n = 20), and AO groups (n = 20). Quantitative sensory testing (QST) was performed preoperatively (baseline) for all three groups and postoperatively at 1 month and 3 months after dental implant placement or pulpectomy (in the IMP group and IP group, respectively). Statistical analyses were completed with one-way and two-way analysis of variance and z score transformations (a = 5%). Results: The main findings of this study indicated that: (1) Elevations in mechanical detection threshold (MDT) and in current perception threshold (CPT) related to C-fiber activation, indicating a loss of function, were found at baseline in IP patients; (2) Somatosensory abnormalities such as allodynia, reduced MDT and mechanical pain threshold (MPT), and impaired pain modulation were found in AO patients; (3) No somatosensory alterations after implant placement were found in the IMP group; and (4) Somatosensory alterations in the form of reduction in the CPT related to C-fiber activation were reported 3 months after pulpectomy in the IP group. Conclusion: This study showed that somatosensory abnormalities were evident in AO and IP patients, and somatosensory alterations were seen in IP patients even 3 months after pulpectomy. However, no somatosensory alterations were seen after implant placement. [ABSTRACT FROM AUTHOR]

Aims. This study evaluated the effects of L-PRF presence and implant surface texture on bone healing around immediately placed implants. Methods. The first mandibular molars of 8 beagle dogs were bilaterally extracted, and implants (Blossom™, Intra-Lock International, Boca Raton, FL) were placed in the mesial or distal extraction sockets in an interpolated fashion per animal. Two implant surfaces were distributed per sockets: (1) dual acid-etched (DAE, micrometer scale textured) and (2) micrometer/nanometer scale textured (Ossean™ surface). L-PRF (Intraspin system, Intra-Lock International) was placed in a split-mouth design to fill the macrogap between implant and socket walls on one side of the mandible. The contralateral side received implants without L-PRF. A mixed-model ANOVA (at α=0.05) evaluated the effect of implant surface, presence of L-PRF, and socket position (mesial or distal), individually or in combination on bone area fraction occupancy (BAFO). Results. BAFO values were significantly higher for the Ossean relative to the DAE surface on the larger mesial socket. The presence of L-PRF resulted in higher BAFO. The Ossean surface and L-PRF presence resulted in significantly higher BAFO. Conclusion. L-PRF and the micro-/nanometer scale textured surface resulted in increased bone formation around immediately placed implants. [ABSTRACT FROM AUTHOR]