Takeda Hiroaki, Nakamura Yoshiki, Handa Hideho, Ishii Hiroaki, Hamada Yoshiki, Seto Kanich
Department of Orthodontics, Tsurumi University School of Dental Medicine, Yokohama, Japan.
J Oral Maxillofac Surg. 2009 Sep;67(9):1844-9. doi: 10.1016/j.joms.2009.04.027.
We examined the movement of the mandible in skeletal Class III patients with a unilateral posterior cross-bite to clarify whether the correction of the cross-bite caused conversion of the masticatory movement from a reverse to a grinding pattern.
We studied 10 adults with mandibular prognathism who had been treated with surgery. The masticatory movement and rhythm (cycle time) during gum chewing were recorded before and after treatment.
The results before treatment demonstrated a high frequency of patterns IV, VI, and VII and a low frequency of patterns I, II, and III on the cross-bite side. After treatment, the masticatory movement on the cross-bite side showed different patterns than from before treatment. The high frequency of pattern VI (reverse pattern) before treatment was significantly reduced, and patterns I and III had significantly increased in frequency after treatment. No significant changes were seen in cycle time, opening phase, occlusal phase, or the closing phase before and after treatment.
These results suggest that correction of a unilateral posterior cross-bite induces conversion of the masticatory pattern from the reverse pattern to the grinding pattern.
我们研究了单侧后牙反合的骨性III类患者下颌骨的运动，以阐明反合的矫正是否会导致咀嚼运动从反向模式转变为研磨模式。
我们研究了10例接受过手术治疗的下颌前突成年患者。记录治疗前后咀嚼口香糖时的咀嚼运动和节律（周期时间）。
治疗前的结果显示，反合侧IV型、VI型和VII型模式的频率较高，而I型、II型和III型模式的频率较低。治疗后，反合侧的咀嚼运动表现出与治疗前不同的模式。治疗前VI型（反向模式）的高频率显著降低，治疗后I型和III型的频率显著增加。治疗前后的周期时间、开口期、咬合期或闭口期均未见明显变化。
这些结果表明，单侧后牙反合的矫正会导致咀嚼模式从反向模式转变为研磨模式。
