A clinical evaluation of masticatory function in maxillary bilateral free-end-saddle removable partial denture in changes of mucosal support area

Abstract

The purpose of this study was to elucidate optimal relations between functional load distribution of periodontal supports and mucosal supports from denture bearing area in maxillary bilateral free-end-saddle RPD. Therefore, specially designed, palatal plate changeable RPDs were designed without changing occlusal relation and all other elements. The denture bearing area were measured by the thin foil method, standardized by Cubscraniophor. After wearing RPD, clinically physiological observation in occlusal contacts and loads were carried out by Prescale with an exclusive computer analyzing system. Masticatory muscular EMG and occlusal contacts were recorded with Prescale at i.p. clenching. Five maxillary bilateral shortened archcases were used for this prosthodontic research and studied in periodically at pre- and post-RPD treatments. These data were analyzed and compared with those of the control group. The outlines of these results were as follows: 1. The relation with mucosal denture supporting area and musculature activities were shown as y = -0.19x2 + 5.3x + 93.8, the maximal value: 13.48 cm2. 2. The direct proportion was observed in relation with anteroposterial location of masticatory center in dental arch and denture bearing area. 3. The optimal denture bearing area was observed in each shortened arch case.