EVALUATION OF THE OCCLUSAL TABLE PATTERN IN REMOVABLE PARTIAL DENTURE WITH UNILATERAL DISTAL EXTENSION SADDLE

Abstract

This investigation was undertaken for the purpose of understanding the function al behavior of unilateral extension saddle removable partial dentures and their optimal design, based on clinical experiments. Mainly, the relation between the pattern of the occlusal table and the transmitting lateral force to the abutment tooth was examined. A specially simulated model fo1 the unilateral mandibular extension saddle denture was devised for this purpose. Devices for measuring the tooth mobility and force applicator, and their recording system were used. Conclusions drawn from this investigation were as follows: (1) An optimal load distribution on the residual ridge under denture saddle was observed when a vertical force was applied on the crest spots of the occlusal table. (2) Reduction of the bucco-lingual width of the occlusal table, particularly in distal area, rationally reduced the lateral transmitting force against the abutment tooth. (3) A lateral force against distal extension saddle had a great effect on the abutment tooth, chiefly on the abutment of indirect retainer. (4) The amount of vertical excursion of distal extension saddle was markedly concerned with the location of loading area when the vertical force was applied on the occlusal table of the denture saddle.