Case-control study on the survival of abutment teeth of partially dentate patients.

OBJECTIVES

Due to the scarce amount of data available, a retrospective analysis of patients treated with removable dental prostheses (RDPs) was performed. The aim of the trial was to evaluate the rate of repairs and failures of attachment-retained RDPs (AR-RDPs) compared to clasp-retained RDPs (CR-RDPs) with respect to cofactors (e.g., type of loading). In this respect, two hypotheses were proposed: AR-RDPs are more prone to repairs than CR-RDPs, and AR-RDPs are more prone to fail than CR-RDPs.

MATERIALS AND METHOD

Two hundred three patients treated with 135 AR-RDPs and 68 CR-RDPs between 1994 and 2006 were evaluated in this trial. The dental treatment was carried out in the clinical training course of senior students. Kaplan-Meier estimates were calculated for the primary end point (repairs) and for the secondary end point (failures).

RESULTS

The survival of CR-RDPs and AR-RDPs did show significant differences regarding repairs (p = 0.034) but not with regard to failures (p = 0.169). Prostheses of the non-axially loaded group showed no significant differences in the frequency of repairs and failures.

CONCLUSIONS

Technical complications occurred more frequently in the CR-RDP group. Taking the higher observation time in the AR-RDP group into account, CR-RDPs are more prone to repairs, especially to those with technical background (e.g., fracture of the metal framework).

CLINICAL RELEVANCE

The use of crowns with rod attachments on tilted teeth seems to be an appropriate treatment approach in order to simplify removable dental prosthesis design.