Minagi S, Ohmori T, Sato T, Matsunaga T, Akamatsu Y
Department of Removable Prosthodontics, Okayama University Dental School, Okayama, Japan.
J Oral Rehabil. 2000 Feb;27(2):175-9. doi: 10.1046/j.1365-2842.2000.00497.x.
Although the mechanical compression of the temporomandibular joint (TMJ), which could be caused by bruxism, would probably result in a slight change of the occlusal relationship, the effect of clenching in the eccentric mandibular position on the occlusal contact has not yet been clarified. This study aimed to investigate the effect of eccentric clenching on bilateral condylar position and thus to estimate any change of occlusal contact. Before and after voluntary clenching, with one third of the maximal voluntary clenching force, for 3 min at the canine edge-to-edge position, vertical deviation of the bilateral condyles was measured at the 1 mm open mandibular position. This was regulated by the three-dimensional position of the anterior reference point which stands for the incisor point. The mean vertical displacement of the highly deviated side of the condyle was 141+/-55 microm, and the calculated mean displacement of the mandibular first molar region of the highly deviated side was 65+/-27 microm. From the results of this study, it was revealed that the eccentric clenching gave rise to three-dimensional deviation of the mandible even when the mandible was in the vicinity of the rest position.
虽然颞下颌关节（TMJ）的机械性压迫（可能由磨牙症引起）可能会导致咬合关系略有变化，但下颌偏位紧咬对咬合接触的影响尚未明确。本研究旨在调查偏位紧咬对双侧髁突位置的影响，从而评估咬合接触的任何变化。在自愿紧咬前和紧咬后，以最大自愿紧咬力的三分之一，在尖牙对刃位置持续3分钟，于下颌开口1毫米位置测量双侧髁突的垂直偏差。这由代表切牙点的前参考点的三维位置进行调节。髁突高度偏斜侧的平均垂直位移为141±55微米，高度偏斜侧下颌第一磨牙区域的计算平均位移为65±27微米。从本研究结果可知，即使下颌处于休息位置附近，偏位紧咬也会导致下颌的三维偏差。
