Journal of Oral Implantology December 2014 - (Page 758)

LITERATURE REVIEW Fit of CAD/CAM Implant Frameworks: A Comprehensive Review Jaafar Abduo Computer-aided design and computer-aided manufacturing (CAD/CAM) is a strongly emerging prosthesis fabrication method for implant dentistry. Currently, CAD/CAM allows the construction of implant frameworks from different materials. This review evaluates the literature pertaining to the precision fit of fixed implant frameworks fabricated by CAD/CAM. Following a comprehensive electronic search through PubMed (MEDLINE), 14 relevant articles were identified. The results indicate that the precision fit of CAD/CAM frameworks exceeded the fit of the 1-piece cast frameworks and laser-welded frameworks. A similar fit was observed for CAD/CAM frameworks and bonding of the framework body to prefabricated cylinders. The influence of CAD/CAM materials on the fit of a framework is minimal. Key Words: implant framework fit, misfit, titanium, zirconia, distortion INTRODUCTION T he passive fit of an implant framework is defined as the simultaneous and even contact of all the fitting surfaces, without the development of strains prior to functional loading.1,2 Obtaining a passive fit between the implant framework and the infrastructure is to minimize biologic and mechanical complications.1,3 In light of the available evidence, this correlation is difficult to assume, as an inevitable degree of inaccuracy would always be present. Further, the clinical approaches to assessing the implant framework fit are crude and only detect gross misfits.2 On these bases, some authors have argued against the importance of passive fit, and have assumed that well-controlled fabrication techniques are sufficient in providing a long-term successful implant treatment.4 Still, until clear guidelines are formulated regarding the acceptable level of implant framework fit, together with a method of confirmation, it is crucial to aim for the best implant framework fit to minimize strain and gap formation. In order to enhance implant framework fit, Melbourne Dental School, Melbourne University, Melbourne, Australia. Corresponding author, e-mail: DOI: 10.1563/AAID-JOI-D-12-00117 758 Vol. XL /No. Six /2014 several processing technologies have been proposed. In general, 2 categories of processing technologies were identified: (1) the addition of a fit refinement step, or (2) the elimination of certain fabrication steps.5 Included in the first category are sectioning and soldering/laser welding, spark erosion, and bonding of the framework body to prefabricated cylinders. The second category includes computer-aided design and computer-aided manufacturing (CAD/CAM). In modern dentistry, CAD/CAM technology is heavily used for toothsupported and implant-supported prostheses. The proposed advantages of CAD/CAM are durability, predictability, and accuracy.6 Furthermore, CAD/ CAM is the only means of producing dental restorations constructed from high strength ceramics, such as zirconia. Given that well-engineered and accurate frameworks can be predictably produced by CAD/CAM, it is possible to move from conventional one-piece casting of highly expensive noble metal alloys. Subsequently, the cost efficiency of the implant treatment will markedly improve. For tooth-supported fixed partial prostheses, there is a lack of compelling evidence supporting the superiority of CAD/CAM restoration fit over restorations fabricated from conventional fabrication techniques. In fact, earlier studies revealed an inferior fit of CAD/CAM restorations on teeth when

Table of Contents for the Digital Edition of Journal of Oral Implantology December 2014

Effect of Splinting in Accuracy of Two Implant Impression Techniques
Assessment of the Stress Transmitted to Dental Implants Connected to Screw-Retained Bars Using Different Casting Techniques
Retentiveness of Various Luting Agents Used With Implant-Supported Prosthesis: An In Vitro Study
Role of rhBMP-2 and rhBMP-7 in the Metabolism and Differentiation of Osteoblast-Like Cells Cultured on Chemically Modified Titanium Surfaces
Coated vs Uncoated Implants: Bone Defect Configurations After Progressive Peri-implantitis in Dogs
Why Guided When Freehand Is Easier, Quicker, and Less Costly?
Advanced Platelet-Rich Fibrin: A New Concept for Cell-Based Tissue Engineering by Means of Inflammatory Cells
Flapless Alveolar Ridge Preservation Utilizing the ‘‘Socket-Plug’’ Technique: Clinical Technique and Review of the Literature
Implants Placed in the Nasopalatine Canal to Rehabilitate Severely Atrophic Maxillae: A Retrospective Study With Long Follow-up
Severe Mandibular Atrophy Treated With a Subperiosteal Implant and Simultaneous Graft With rhBMP-2 and Mineralized Allograft: A Case Report
Full-Mouth Rehabilitation of a Patient With Ectodermal Dysplasia With Dental Implants
The 2-Visit CAD-CAM Implant-Retained Overdenture: A Clinical Report
Assessment of Implant-Related Treatment With Edited Three-Dimensional Reconstructed Images From Cone-Beam Computerized Tomography: A Technical Note
Retrieval of a Separated Implant Screwdriver Fragment
Correction of Esthetic Complications of a Malpositioned Implant: A Case Letter
Fixed Partial Denture Treatment With Mini Dental Implants
Replacement of an Implant and Prosthesis in the Premaxilla Due to a Malposition and Prosthetic Failure: A Clinical Case Letter
A New Restorative Technique for the Perishing Implant Due to Abutment Screw Fracture
Fit of CAD/CAM Implant Frameworks: A Comprehensive Review

Journal of Oral Implantology December 2014