青年女性浅层嚼肌B超形态与牙弓形态关系的研究

目的了解肌肉形态、功能与牙弓形态之间的相互作用关系,探讨错牙合畸形的形成机理。方法本研究采用超声成像技术测量31例正常牙合青年女性浅层嚼肌横截面的周长、面积、横径、平均厚度、最大厚度及纵截面的长度,并将测量结果与牙弓测量指标进行统计相关分析。结果超声测量浅层嚼肌横截面的周长、面积、横径、平均厚度、最大厚度对下颌牙弓磨牙区宽度影响明显,且成负相关;横截面的周长、面积、横径与下颌牙弓前段长度关系显著,呈正相关,厚度与下颌牙弓前中段长度呈正相关,周长与下颌牙弓后段长度呈正相关;横截面的面积、周长与上颌牙弓长度成正相关;纵截面长度与上下颌尖牙角、下颌双尖牙角成负相关关系。结论浅层嚼肌形态与牙弓形态相关关系显著,浅层嚼肌形态越粗壮,功能越强,则越有利于面下1/3矢状向发展,而限制其宽度发育。

Study of relationship between ultrasonographic measurements of masseter muscle and dental arch form

Objective To investigate the relationship between the ultrasonographic measurements of the masseter muscle and the morphology of the dental arch form. Methods The subjects consisted of 31 females with normal occlusion. Their mean age was 21.3 years old. Ultrasound technique was applied to measure the image of masseter muscle. The indices included perimeter, area, width, average thickness, maximal thickness of cross section and length of the vertical section of the masseter muscle. The dental arch forms were also surveyed by recording some indices such as width, length and angle. Correlation analysis was done between the indices of masseter muscle image and dental arch forms. Results The results showed that the stockier the massoter muscle, the narrower the dental arch form and the masseter muscle also had a negative effect on the canial angle of the dental arch. Conclusions The dental arch forms were notably influenced by the functional activities of the masseter muscle.