Effects of periodontal support and fixed splinting on load transfer by removable partial dentures

Statement of problem. Periodontally compromised abutment teeth complicate the design of bilateral distal extension removable partial dentures. Purpose. This study investigated the stress induced in the remaining oral structures by a bilateral distal extension I-bar-retained RPD with periodontally involved abutments in a photoelastic simulation model. Material and methods. Composite photoelastic models were used as a simulation model in determining the stress generating characteristics of I-bar RPDs with varying degrees of periodontal involvement of the distal abutments. Effects of fixed splinting were considered. Results and Conclusions. Under the same load conditions, the highest stresses developed in the model with the largest osseous defect. Increasing the number of splinted teeth did not provide a proportional decrease in maximum stress levels. The more severe the osseous defect, the greater assistance was provided by splinting to periodontally sound teeth. This simulation study suggests that routine cross-arch splinting may not be appropriate.