局所機能圧・負担圧に関する基礎的研究 ＩＩ‐２． 上顎総義歯の中心こう合位について

Abstract

The purpose of the present study was to elucidate how the distribution of bearing stress and dynamics of basal seat under upper complete denture on during mastication give influence on the disorder of the under denture. First, evaluation was made on bearing stress of basal seat under upper complete denture at the centric occlusion on the alveolar bone.The results were as follows:1. Distribution of bearing stress Compared with the case of alveolar mucosa, the bearing stress on the alveolar bone was remarkably low.The bearing stress on the alveolar ridge was higher in both alveolar mucosa and alveolar bone than on the other measuring points. In paticular, the bearing stress was highest on the incisive papilla. Next to the alveolar ridge, it was high on the border. On the buccal region and palate, the bearing stress was lower compared with the alveolar ridge and border. The postdam region was the lowest.2. Dynamics of bearing stress1) The time of occurrence of the bearing stress on the alveolar bone was shorter than on the alveolar niucosa. Particularly, this was more remarkable on maxillary tuberosity and palate.2) Time of the bearing stress occurrence was approximately equal to the load reaching time, but it was remarkably shorter on maxillary tuberosity and a part of the palate.