Studies on Mastication and Biting Forces of Differences from Occlusal Form of Artificial Posterior Teeth of Complete Denturers

Until the present, artificial teeth that varied form, size and shade are used, and studied in large numbers. But it did'nt at the same time biting forces, masticating forces and the electoromyography of differences from occlusal form of artificial teeth of complete dentures. By way of finding out how the occlusal form of artificial teeth has a influences upon the masticatory functions of complete dentures, the author uses the semi-conductor apparatus developed by Moriya and Fukamizu. The biting forces, masticating forces and forces in the swallowing period of the upper first molars on the complete denture wears (6 males) from 50 to 60 in age at differences from occlusal form of artificial teeth are recorded at the same time as the electoromyography of masseters and temporalis of left and right side.As the result of these efforts, the following conclusions are obtained.1. The biting forces in upper first molars of the 30 degree cusp teeth are larger than 0 degree cusp teeth. Especially the biting forces of the 0 degree cusp teeth are'nt found at eccentric occlusion.2. The masticating forces in all foods of the 30 degree cusp teeth are smaller than 0 degree cusp teeth, but forces in the swallowing period are larger.3. As for amount of electoric discharge activity of the masseter and temporalis during masticating each foods, 30 degree cusp teeth have a tendency to be small quantity to 0 degree cusp teeth.4. Interval of electoric discharge activity of masseter and temporalis are'nt found difference between each teeth, but as for the duration, term and proportion of duration to term, 30 degree cusp teeth have a tendency of to be small to 0 degree cusp teeth.