正常青年女性下颌3种功能位浅层咬肌超声形态研究

目的:建立正常青年女性浅层咬肌在下颌处于不同功能位置时超声形态的正常值,为评价正畸患者咬肌功能提供参考。方法:采用超声成像技术测量了31例正常青年女性下颌处于姿势位、最大紧咬位、最大前伸位时浅层咬肌横截面的面积、周长、横径、平均厚度、最大厚度及纵截面的长度,得出各指标均值,并比较下颌处于不同功能位置时浅层咬肌形态的差异。结果:下颌处于3种功能位时各测量指标差异有显著性,最大紧咬位浅层咬肌收缩,最大前伸位咬肌牵张,姿势位时浅层咬肌的各项指标则介于两者之间。结论:超声成像技术是检测浅层咬肌形态以诊断其下颌功能位置的一种有效方法。

A study of ultrasound images under 3 different functional mandibular positions in young females]

OBJECTIVE: The aim of this study was to establish the average of superfacial masseter muscle of young females with normal occlusion, and further supply a clue for dentists to evaluate the muscle function of patients with malocclusion. METHODS: Totally 31 young females were investigated in this study, whose mean age was 21 years and 4 months old. Ultrasound technique was applied to obtain the ultrasound parameters of images, including area, width, mean thickness, maximal thickness of the cross-section and the length of the vertical-section of the masseter muscle under relaxing, maximal clenching and maximal protruding condition. The data were analyzed using ANOVA analysis. RESULTS: The mean value and standard deviation of every parameter were figured out and it was found that there was a significant difference between relaxing and maximal clenching as well as maximal protruding. CONCLUSION: The result indicates that ultrasonic technique is an effective method for describing superfacial masseter muscle morphology and diagnosing its function.