The effect of partial denture design on abutment tooth and saddle movement.

A laboratory investigation designed to simulate the effect of loads applied to a free-end saddle partial denture was carried out. Abutment tooth and also saddle movement were monitored using a photogrammetric method. Loads applied to the denture saddle were transmitted through the occlusal rest and also the clasp components causing movement of both denture saddle and the abutment tooth. The direction of abutment tooth movement was towards the mesial, whether the occlusal rest was situated on the mesial or distal aspect of the tooth crown. It was also evident that the design of the clasp unit used affects the magnitude and direction of abutment tooth movement.