Posterior Bite Collapse: Guidelines for Treatment Based on Form and Function.

The clinical syndrome known as posterior bite collapse (PBC) consists of multiple, often pathognomonic factors that deviate from normal, or an occlusion wherein the posterior occlusion is compromised and may ultimately destroy the functional protective capacity of the entire dentition. Secondary clinical sequelae may include accelerated periodontitis progression, temporomandibular disorders (TMD), increasing mobility/fremitus, additional tooth loss, anterior flaring, and loss of occlusal vertical dimension. Etiologic factors may include tooth loss without replacement, orthodontic malocclusions and dentoskeletal disharmonies, periodontitis, accelerated retrograde occlusal/interproximal wear, severe caries, or iatrogenic and conformative dentistry. Not all PBC cases require treatment, but treatment is dependent upon the periodontium's stability and its ability to maintain its form and function. Treatment decisions can also be dependent upon periodontal health, caries, function, occlusion, TMD, esthetics, and phonetics. The purpose of this article is to provide general treatment guidelines based on form and function of the masticatory system for restoring a PBC case when treatment is necessary. This article does not discuss specific mechanics for restoring PBC cases.

Posterior Bite Collapse and Diagnostic Grading for Periodontitis.

The syndrome known as posterior bite collapse (PBC) has taken on multiple definitions over the years since its first introduction in 1964 by Morton Amsterdam and Leonard Abrams. In 2017, the World Workshop in the Classification of Periodontal and Peri-implant Diseases and Conditions proposed a staging system for periodontitis, defined by severity and extent of periodontal breakdown. Within this staging system, Stage IV periodontitis can include PBC. However, without a clear delineation regarding the clinical presentation or pathogenesis of PBC, this further obfuscates its definition. It is therefore the goal of this article to reexamine the original definition of PBC as defined by Amsterdam and Abrams, present an updated definition, and propose a clinical grading system of PBC to coincide with the 2017 staging of periodontitis.

Tooth-to-Implant-Supported Fixed Partial Denture: A Comprehensive Overview of Systematic Reviews.

OBJECTIVES: Tooth-to-implant-connected prostheses have been described as a possible treatment option for patients with long-span edentulous situations that were not conducive for placement of an adequate number of supporting implants. In this comprehensive overview of systematic reviews, the incidence of complications and the long-term survival rates of tooth-to-implant-supported fixed partial dentures (FPDs) were evaluated to determine whether it is a viable treatment. MATERIALS AND METHODS: A systematic search of 5 electronic databases was conducted for systematic reviews and meta-analyses of tooth-to-implant-supported FPDs up to January 2017. The articles were AMSTAR rated for methodological quality, and low-quality articles were eliminated. RESULTS: The initial search yielded 369 reviews in PubMed, 248 in Web of Science, 49 in EMBASE, 63 in Cochrane Library, and 27 in Google Scholar. After removal of duplicates and after full-text analysis, 5 were selected for the overview. CONCLUSIONS: Within the limitations of this overview, it was concluded that (1) the 10-year survival rates for tooth-to-implant FPDs were lower than the 5-year survival rates, (2) the tooth-to-implant FPDs' survival was lower than the individual abutment tooth or implant supporting it, (3) the biological and technical complications were more at 10 years compared with 5 years, and (4) the intrusion of the abutment teeth was more in the nonrigid connection FPDs than the rigid connection FPDs. Therefore, tooth-to-implant FPDs are a viable option but should be considered secondary to other available options with higher long-term survival rates and lower complications.

Common Prosthetic Implant Complications in Fixed Restorations.

Many clinicians consider implants to be one of the most important innovations in dental care. Even so, over the past 40 years of implant dentistry, complications have been a constant struggle for restorative dentists, surgeons, and patients alike. Implant-related problems can be particularly challenging and frustrating, especially given that an implant is thought to be a "lifetime" solution expected to yield minimal difficulties. This, however, is not necessarily the case with prosthetic restorations. With innovations in implant technology continuing to rapidly advance, maintaining knowledge of all the latest developments can be challenging for clinicians. The purpose of this article is to provide a basic understanding of the treatment, management, and prevention of common prosthetic and technical implant complications seen in the office of a restorative dentist.

A meta-analysis on the effect of implant characteristics on the survival of the wide-diameter implant.

The purposes of the study are to study the implant survival of the wide-diameter implant and to analyze if the length, the implant surface, or the placement location has any effect on its survival. Electronic databases were searched from inception to Dec 2014. Studies included in the review had implants placed in areas of adequate bone width and had clear inclusion and exclusion criteria for patient selection. Immediately placed and immediately loaded implants were excluded. A meta-analysis was done using the "random effects" model on the included studies. And, a meta-regression was used to evaluate the effects of location, length, and surface on the implant survival. Of the six studies selected, three evaluated surface-treated implants and three machined implants. The overall pooled survival rate of the wide implant is 96.3 %. The meta-regression showed that when using a wide implant, neither its surface nor its length nor its position in the maxilla or mandible adversely affected its survival (P > 0.05). This meta-analysis concluded that the location, length, and surface of the wide-diameter implant did not affect its survival and therefore suggested that when the conditions of the implant site corresponded to the inclusion criteria of our meta-analysis, choosing a wide-diameter implant in the posterior mandible or maxilla, where implant length may be limited by the nerve or the sinus, the use of a short implant regardless of its surface would not affect its survival.

Assessment of occlusion curriculum in predoctoral dental education: report from ACP Task Force on Occlusion Education.

PURPOSE: The purposes of this report were to (1) assess the current occlusion curriculum in the predoctoral prosthodontic education of US dental institutions and (2) to examine the opinions of faculty, course directors, and program directors on the contents of occlusion curriculum. MATERIALS AND METHODS: The Task Force on Occlusion Education from the American College of Prosthodontists (ACP) conducted two surveys using a web-based survey engine: one to assess the current status of occlusion education in predoctoral dental education and another to examine the opinions of faculty and course directors on the content of occlusion curriculum. The sections in the surveys included demographic information, general curriculum information, occlusion curriculum for dentate patients, occlusion curriculum for removable prosthodontics, occlusion curriculum for implant prosthodontics, temporomandibular disorder (TMD) curriculum, teaching philosophy, concepts taught, and methods of assessment. The results from the surveys were compiled and analyzed using descriptive statistics. The results from the two surveys on general concepts taught in occlusion curriculum were sorted and compared for discrepancies. RESULTS: According to the predoctoral occlusion curriculum surveys, canine guidance was preferred for dentate patients, fixed prosthodontics, and fixed implant prosthodontics. Bilateral balanced occlusion was preferred for removable prosthodontics and removable implant prosthodontics. There were minor differences between the two surveys regarding the occlusion concepts being taught and the opinions of faculty members teaching occlusion. CONCLUSION: Two surveys were conducted regarding the current concepts being taught in occlusion curriculum and the opinions of educators on what should be taught in occlusion curriculum. An updated and clearly defined curriculum guideline addressing occlusion in fixed prosthodontics, removable prosthodontics, implant prosthodontics, and TMD is needed.