Effects of load on the temporomandibular joints with different occlusal positions using a dry skull

Abstract

We investigated the magnitude of occlusal pressure and stress distribution on the condylar head of a dry human skull when an experimental masseter muscle was activated at different clenching positions. Occlusal pressure increased as the occlusal support was moved distally. Clenching on the first premolar produced the strongest pressure on the head of the condyle on the nonworking side. Decreased pressure was observed on the front, top, lateral side and medial side of the head, in that order. Clenching from the region of the second premolar to the third molar produced the largest pressure on the top and front of the head. Clenching on the first premolar produced little pressure on the frontal, lateral and medial regions of the head of the condyle on the working side. Pressure on the front of the head of the working side condyle decreased with occlusion on the posterior teeth. The head tended to float in the mandibular fossa with occlusion on the second and third molars. We found that pressure on the temporomandibular joints changed with the position of the occlusal force.Shika Igaku(J Osaka Odontol Soc) 2003 Dec; 66(4): 331-338.