正常牙合青年男性咀嚼肌不同功能位超声形态研究

Ultrasound Images of the Masticatory Muscles under Different Functional Positions in Young Males

目的:建立正常牙合青年男性浅层嚼肌、颞肌前束在下颌处于不同功能位置时超声形态正常值,比较其差异,为评价正畸患者浅层嚼肌、颞肌功能提供参考。方法:应用超声成像技术测量69位正常牙合青年男性下颌分别处于姿势位、最大紧咬位、最大前伸位时浅层嚼肌周长、面积、宽度、最大厚度、平均厚度、长度及颞肌前束最大厚度、平均厚度并对其不同功能位置的各项形态指标进行比较分析。结果:下颌处于姿势位时浅层嚼肌、颞肌前束的厚度与最大前伸位时比较,有显著性差异(P<0.05);下颌处于最大紧咬位时浅层嚼肌的各项超声形态指标及颞肌前束厚度与最大前伸位及姿势位时比较,有显著性差异(P<0.05)。结论:处于不同功能位浅层嚼肌、颞肌前束超声形态差异显著。

Objective： To establish the average of superfacial masseter and anterior temporalis of young males with nomal occlusion, and to identify the possible morphology characteristics differences in ultrasound images of the mas seter and anterior temporalis under different functional positions,and to establish the base for dentists to evaluate the muscle function of patients with malocclusion. Methods： The subjects consisted of 69 males with nomal occlusion （mean age：23. 6 years）. Ultrasound scanning was used to measure the perimeter, area, width, mean thickness, maximal thickness and length of masseter muscle and mean thickness and maximal thickness of anterior temporaliis. All items were measured under relaxing, maximal clenching and maximal protruding mandibular position. Results： The thickness of superfacial masseter and anterior temporalis were statistically significant different between in relax- ation and in maximal protruding position （P^0.05）. The ultrasound parameters of images of superfacial masseter and the thickness of anterior temporalis in maximal clenching were statistically significant different from those in the relaxing and in the maximal protruding position （P＇~0.05）. Conclusion： There were statistically significant differ- ences which was found in the ultrasound parameters of images of superfacial masseter and anterior temporalis under different mandibular functional positions.