Title: 3206 - Estimated Loss of Overdenture Abutment Teeth – Review and Meta-Analysis


Alexander Mercouriadis-Howald, University of Bern
Noemie Rollier, University of Bern
Sayaka Tada, Niigata University
Gerald McKenna, Queens University Belfast
Kensuke Igarashi, The Nippon Dental University
Martin Schimmel (Presenter)
University of Bern


Objectives: To analyze the available evidence in the English, German and Japanese literature on the survival and complications of natural teeth with cast copings used to retain overdentures (ROD). The focused question for the review was: “In partially edentulous patients with RODs, what is the estimated annual loss of abutment teeth and complications of the abutment teeth with precision attachments?”

Methods: A systematic search strategy was conducted using MeSH terms and pre-defined criteria. Two groups of researchers searched Pubmed, CENTRAL, Embase (English, German), Ichushi-web (Japanese) as well as hand searching. Data were extracted independently by the two groups. The estimated frequency of abutment tooth loss was calculated from data on the number of lost teeth and exposure time. A meta-analysis was conducted to estimate the annual frequency of abutment tooth loss across all included studies.

Results: A total of 4791 eligible studies from PubMed, Embase, and CENTRAL were identified. An additional 316 articles were found from the Ichushi-Web and further 131 articles from additional sources. From those manuscripts, 19 reported relevant outcome data that was then extracted. The pooled data included a total of 1'954 abutment teeth with a combined total exposure time of 9'098 years. The estimated linear rate of loss was 1.76%/ year (95%CI 1.13; 2.72). Caries and periodontal infections were identified as the most common reasons for abutment tooth loss.

Conclusions: Natural tooth retained overdentures often constitute the last resort before edentulism and might aid in this transition, especially in very old patients with reduced adaptive capacities. Given correct design, preparation and aftercare, RODs still are a valid treatment option as the natural abutments preserve alveolar bone, muscle mass, maximum bite force, inter-occlusal sensitivity and chewing efficiency.

Disclosure Statement:
The submitter must disclose the names of the organizations with which any author have a relationship, the nature of the relationship, and the clinical or research area involved. The following is submitted: NONE