Success rate and failures for fixed partial dentures after 20 years of service: Part I

The objective of this study was to identify failures and to assess rate for fixed partial dentures constructed 20 years earlier by general practitioners in Sweden.

The original group consisted of 164 patients who had received prosthodontic treatment in 1974 comprising fixed partial dentures with at least five units. They had all been selected at random from the files of the Swedish Federal Dental Insurance Register. Twenty years later, 98 of them could be located and 72 of them agreed to participate in a clinical examination. The majority of drop-outs of the original group had died, could not be traced, or could not participate because of medical reasons. The examination focused on removed prostheses and/or units and a number of other clinically valid variables that will be reported in a forthcoming article. The 26 patients not participating in the clinical examination were interviewed by telephone.

The examined participants had a total of 140 fixed partial dentures, 557 retainers, and 383 pontics still in service. When the number of failed and removed prostheses was calculated, a cumulative success rate of 65% was found, i.e., one third had been lost since 1974. There was no difference in failures between fixed partial dentures with or without cantilevers during the previous 8 years compared to the first 12 years in service. Loss of retention together with periodontal and esthetic problems, wear, and discoloration of acrylic veneers were the most frequently reported reasons for removal.

The cumulative success rate for fixed partial dentures placed in 1974 was 65%. Failed prostheses had in most cases been replaced by a new fixed partial denture.