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Dental treatments in hemophilic patients are challenging, and the absence of adequate preparation for the procedures can be life-threatening. This letter describes a delayed postoperative bleeding after multiple dental implants with sinus floor elevation in a patient with mild hemophilia A. [ABSTRACT FROM AUTHOR]

Purpose: The aim was to evaluate the stress concentration caused by different cross sections of bar frameworks and clip materials used to retain overdentures. Materials and Methods: Three-dimensional models of a severely resorbed arch, an overdenture retained by two implants, and a bar-clip attachment system were made. A total of twelve models were made according to the cross section of the bar framework (round, oval, or Hader), clip material (gold or plastic), and presence of misfit. A vertical misfit of 100 μm between the implant and the bar framework was made on the right implant. Finite element models were obtained by importing the solid model into mechanical simulation software. The base of the mandible was set to be the fixed support, and a pressure of 100 MPa was applied to the right mandibular first molar. The analysis was made by means of von Mises stress for the prosthetic components and microstrain to the bone tissue. Results: Round bars led to lower values of stress in the clip and prosthetic screw of the ill-fitted component and lower microstrain values in the peri-implant bone tissue. The lowest values of stress in the bar were observed in the Hader groups. Plastic clips reduced the stress concentration in all structures compared with gold clips. Conclusion: The clip material and the cross section of the bar framework influenced the stress distribution in overdentures retained by a bar-clip system presenting vertical misfit. [ABSTRACT FROM AUTHOR]

Purpose: This study evaluated the vertical misfit of implant-supported frameworks made using different techniques to obtain passive fit.Materials and Methods: Thirty three-unit fixed partial dentures were fabricated in cobalt-chromium alloy (n = 10) using three fabrication methods: one-piece casting, framework cemented on prepared abutments, and laser welding. The vertical misfit between the frameworks and the abutments was evaluated with an optical microscope using the single-screw test. Data were analyzed using one-way analysis of variance and Tukey test (α = .05).Results: The one-piece casted frameworks presented significantly higher vertical misfit values than those found for framework cemented on prepared abutments and laser welding techniques (P < .001 and P < .003, respectively).Conclusion: Laser welding and framework cemented on prepared abutments are effective techniques to improve the adaptation of three-unit implant-supported prostheses. These techniques presented similar fit. [ABSTRACT FROM AUTHOR]

Purpose: To assess, through a systematic review, the influence of different implant geometries on clinical longevity and maintenance of marginal bone tissue. Methods: An electronic search was conducted in MEDLINE, Scopus, and Web of Science databases, limited to studies written in English from 1996 to 2017 using specific search strategies. Only randomized controlled trials (RCTs) that compared dental implants and their geometries were included. Two reviewers independently selected studies, extracted data, and assessed the risk of bias of included studies. Results: From the 4006 references identified by the search, 24 were considered eligible for full‐text analysis, after which 10 studies were included in this review. A similar behavior of marginal bone loss between tapered and cylindrical geometries was observed; however, implants that had micro‐threads in the neck presented a slight decrease of marginal bone loss compared to implants with straight or smooth neck. Success and survival rates were high, with cylindrical implants presenting higher success and survival rates than tapered ones. Conclusions: Implant geometry seems to have little influence on marginal bone loss (MBL) and survival and success rates after 1 year of implant placement; however, the evidence in this systematic review was classified as very low due to limitations such as study design, sample size, and publication bias. Thus, more well‐designed RCTs should be conducted to provide evidence regarding the influence of implant geometry on MBL and survival and success rates after 1 year of implant placement. [ABSTRACT FROM AUTHOR]

Framework misfit is a common problem observed in overdentures, which might result in prosthetic and biological complications. The aim of this study was to evaluate the influence of vertical misfit and clip material on the stress distribution in an overdenture-retaining bar system under masticatory loading. A 3-D finite element model of a resorbed jaw was created, including two implants and a bar-clip retained overdenture. A pressure of 100 MPa was applied to the right mandibular first molar. Different vertical misfit levels (50, 100, and 200 µm) and clip materials (plastic or gold) were evaluated. Data were evaluated using von Mises stress and microstrain. Vertical misfit amplification caused an increase in the microstrain values in the peri-implant bone tissue next to the ill-fitted component and increased the stresses in the prosthetic screws. The clip material influenced the stress and microstrain distribution in the prosthetic components and bone tissue. The levels of vertical misfit seem to be closely linked with the stress values in the prosthetic screws, mainly to that of the ill-fitted component. The gold clip presented an increase in the stress compared to the plastic clip. [ABSTRACT FROM AUTHOR]