Effects of difference of occlusal splint contacts on masticatory system

Abstract

The short-term effects of the difference of occlusal splint contacts on the jaw function were investigated on five healthy subjects. The maxillary stabilization splint (S-type) was fabricated and sectioned into three parts: an anterior section (A-type) and two posterior sections (P-type). These 3 types of splints were used for 10 days for each subject. The EMG activity of the masseter and the anterior and the posterior temporal muscles were measured during the maximum clenching in the intercuspal position and on the wearing splint. Subsequently on the bite force-measuring device with two transducers the bite and the EMG activity were measured during the maximum clenching, and the intercuspal occlusal contacts were recorded. The results were as follows: 1. After wearing the P-type, the total EMG activity during clenching in the intercuspal position was decreased, then increased after removal. 2. After wearing the S-type and the A-type the anteroposterior distribution of the bite force during clenching was changed, then returned after removal. 3. After wearing the A-type, the occlusal contact area of the anterior teeth in the intercuspal position was decreased, then increased after removal, while after wearing the S-type and the P-type that of the posterior teeth was decreased, then increased after removal.