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Purpose: The aim of this systematic review was to compare straight-line and offsetimplant configurations for three-element implant-retained prostheses. Materials and Methods: Two independent reviewers conducted a review onPubMed/Medline, EMBASE, and Cochrane Library for studies published in En-glish, from January 1, 1995 to January 17, 2014. A systematic review was conductedfollowingthePRISMAstatement.Allrelevanttitleswereselectedaccordingtoinclu-sion/exclusioncriteria.Fromthispooloftitles,abstractsandfulltextswerereviewed. Results: Atotalof6080titleswereidentifiedwiththeinitialsearch.Twenty-onewereselected based on title and abstract. Of these, after discussion and complete reading,12studieswereselectedaccordingtotheinclusionandexclusioncriteria,allofwhichwere in vitro studies. Conclusions: A systematic review of the current literature showed only in vitroevidence that there is no consensus on the advantage of using an offset configurationimplant compared to those in straight-line configuration, even though some studiespresent a slight improvement of bone stress distribution when an offset implant isunder oblique loading (PICO).At present, the use of dental implants to rehabilitate patientswith tooth loss has become a clinical reality.

Purpose The aim of this study was to assess the influence of cusp inclination on stress distribution in implant-supported prostheses by 3D finite element method. Materials and methods Three-dimensional models were created to simulate a mandibular bone section with an implant (3.75 mm diameter x 10 mm length) and crown by means of a 3D scanner and 3D CAD software. A screw-retained single crown was simulated using three cusp inclinations (10 degrees, 20 degrees, 30 degrees). The 3D models (model 10d, model 20d, and model 30d) were transferred to the finite element program NeiNastran 9.0 to generate a mesh and perform the stress analysis. An oblique load of 200 N was applied on the internal vestibular face of the metal ceramic crown. Results The results were visualized by means of von Mises stress maps. Maximum stress concentration was located at the point of application. The implant showed higher stress values in model 30d (160.68 MPa). Cortical bone showed higher stress values in model 10d (28.23 MPa). Conclusion Stresses on the implant and implant/abutment interface increased with increasing cusp inclination, and stresses on the cortical bone decreased with increasing cusp inclination.

Interim restorations are frequently used in prosthodontic treatments. Many complex situations require the combination of fixed and removable partial prostheses. An appropriate interim restoration design that accurately implements the treatment plan is necessary to prepare the oral cavity for the prostheses, and to contribute to the preservation and health of remaining natural teeth, bone support, and gingival tissues. This report describes a modified technique for construction of interim restorations with a combination of fixed and removable partial prostheses. The technique consists of the construction of a milled fixed prosthesis and removable partial denture with metallic framework for use during extensive treatment, improving masticatory function and esthetics and preserving the periodontal health of supporting structures. This interim restoration can also serve as a template for the definitive restoration, allowing patient and dentist to evaluate appearance and function and helping to ensure the success of the definitive restoration.