咬合力による下顎の変位に関する研究

第1報実験方法の確立

抄録

Part of the biting force is believed to be transmitted to the temporomandibular joint and cause interarticular pressure. In this paper, we shall examine bite-pressure during mastication and employ a method which estimates this pressure from mandibular displacement measured by the face-bow.
To ensure that interarticular pressure is accurately measured, mandibular displacement should only refer to this pressure. But previous studies have never mentioned this point. Its clarification required the following experimental conditions:(1) that the object bitten would not become deformed, (2) that the mandible would not bend, and (3) that tooth movement be prevented. Considering object size and location in normal crushing, we opted for the followings limitations:(1) that the object be located at the first molar, and (2) that the vertical dimension of the incisal point be less than 10 [mm].
We manufactured an intraoral appliance consisting of upper and lower metal clutches, which strictly limit tooth movement and mandibular bending. As an immovable object, a pivot was fixed to the clutch which satisfied the limitations referred to above. The experiments proved that the pivot moves a distance of less than 0.15 [mm] during clenching, which limits the accuracy of this method.