Comparison of Mandibular Displacement from Habitual Occlusal Position to Intercuspal Position in Normal Adults and Volunteers with Temporomandibular Disorders

• Published in: Nihon Hotetsu Shika Gakkai Zasshi Vol. 47; no. 1; pp. 117 - 124
• Main Authors: Park, Gang-Suk, Kawazoe, Takayoshi, Sato, Masaki
• Format: Journal Article
• Language: Japanese
• Published: Japan Prosthodontic Society 10.02.2003
• Subjects: intercuspal position; occlusal examination; silicone occlusal registration; temporomandibular joint noise
• ISSN: 0389-5386; 1883-177X
• DOI: 10.2186/jjps.47.117

Purpose: The purpose of this study was to clarify the differences in amount and direction of mandibular displacement from habitual occlusal position to intercuspal position, between normal adults and volunteers with temporomandibular joint (TMJ) noise. Methods: Six normal adults, and six volunteers with TMJ noise, participated in this study. Two silicone occlusal registrations were taken for each subject with different occlusal forces: light clenching, and 30% maximum voluntary clenching (MVC). The silicone occlusal registration was digitized by a non-contact three-dimensional form measuring device. The cranio-facial bones were reconstructed from CT data, and the frame of reference on the cranio-facial system was established using anatomical landmarks. The marker-registration of 3 D-data, the silicone occlusal registration and cranio-facial bones, were made by teflon balls. The mandibular displacement was estimated by the relationship of the maxillary and mandibular occlusal surfaces. The parameters of mandibular displacement, movement of dentition (MOD), and movement of condyle (MOC), were selected. Results: The mandibular displacement in the volunteers with TMJ noise was larger than that in the normal adults. The direction of MOD was superior, and the direction of MOC was posterior, in all of the volunteers with TMJ noise. Conclusions: These results suggested that the mandibular displacement from habitual occlusal position to intercuspal position was associated with noise in the joint.