The influence of craniofacial form on bite force and EMG activity of masticatory muscles. VIII-1. Bite force of complete denture wearers.

Today, Japan as a society is aging. The average life expectancy of Japanese people is approximately 80 years. One result of this is that preservation of masticatory functions in elderly people has become increasingly important from the viewpoint of quality of life. In the furture, the use of dentures in facilitating masticatory functions as a substitute for teeth that are lost during the aging process will assume greater significance. Accordingly, appropriate evaluation and judgment of complete dentures for edentate jaws is crucial. This study was designed to elucidate the effects of the craniofacial form in complete denture wearers on the mode of activity of gnathic functions. First, subjects wearing complete dentures in both the upper and lower jaws were instructed to carry out vertical clenching, and bite force direction was determined. These data were then related to the subject's craniofacial morphology. These results suggest that the bite force direction in complete denture wearers is not affected by gender differences, but is closely associated with lateral craniofacial morphology, and that appropriate setting of occlusal plane and the occluded vertical dimension is extremely important in the preparation of complete dentures. (J. Oral Sci. 41, 19-27, 1999)