A Study of Bite Force Distribution on the Dental Arch in Normal Subjects.

The purpose of this study was to clarify the bite force distribution on the dental arch during five types of clenching; bilateral, left and right unilateral, and protrusive and retrusive clenching. Bite forces on each mandibular tooth was measured by using pressure sensitive film, “Dental Prescale 50 H, type R”(Fuji Photo Film, Co., Japan), in six normal subjects with natural dentition. The bite force distribution was defined as the proportion of bite force on each tooth to the total bite force.The proportion of bite force on the tooth located more posteriorly was higher during bilateral clenching. During left and right unilateral clenching, the teeth on the clenching side showed a higher proportion of bite force as compared with that during bilateral clenching. During protrusive clenching, a higher proportion of bite force on incisors, canine, and premolars and a lower proportion on molars were observed as compared with that during bilateral clenching. A higher proportion on the first premolar was observed during retrusive clenching.These result suggested that constant regularities of bite force distribution associated with clenching types can be recognized and that regularities could be useful guidelines for occlusal diagnosis.