前伸头位对咀嚼肌功能活动时的肌电影响

Effect of forward head posture on the electromyogrphy of masticatory muscles during functional activities

目的:研究前伸头位对牙尖交错位自主用力紧咬和吞咽两功能活动时咀嚼肌肌电活动的影响。方法:以30名健康正常青年女性受试者为研究对象,应用BioEMGII型表面肌电测量仪,测量正常人群分别在自然头位和最大前伸头位情况下,牙尖交错自主用力紧咬以及吞咽时颞肌前束(TA)、咬肌(MM)、胸锁乳突肌(SCM)、二腹肌前腹(DA)的肌电幅值,并对结果进行统计学分析。结果:最大前伸头位吞咽时TA、MM、SCM、DA的肌电幅值以及最大前伸头位牙尖交错位自主用力紧咬时MM和DA的肌电幅值与自然头位时相比增高且具有统计学意义(P<0.05);最大前伸头位牙尖交错位自主用力紧咬时TA以及SCM的平均肌电幅值高于自然头位时的肌电幅值,但差别没有统计学意义(P>0.05)。结论:吞咽活动时各咀嚼肌对最大前伸头位有着明显的反应,牙尖交错位紧咬时MM和DA对前伸头位反应明显,最大前伸头位时各咀嚼肌肌紧张度增加,肌电活动增强。

Objective To study the effect of forward head posture on the electromyogrphy of masticatory muscles during two functional activities-voluntary clenching in intercuspal position （ICP） and swallowing. Methods The electromyography（EMG） of bilateral anterior temporalis（TA）,masseter muscles（MM）, sternocleidomastoid muscles（SCM） and anterior digastric muscles（DA） of maximum forward head posture（FHP） and natural head posture（NHP） was taken respectively in 30 heath young female subjects to measure the myoelectric value during voluntary clenching in ICP and swallowing by means of Bio PAK system. Results EMG activities of MM and DA at maximum FHP during voluntary clenching in ICP were significantly higher than in control group（NHP） （P〈0.05）. EMG activities of TA ,MM,SCM and DA at maximum FHP during swallowing were also significantly higher than in control group （P〈0.05）. There was no significant statistic difference in the myoelectric value of TA and SCM in ICP between FHP and NHP （P〉0.05）,although the value at FHP was higher than the control group. Conclusion Masticatory muscles activities during swallowing are responded to maximum FHP obviously.EMG activities of MM and DA during clenching in ICP also have significant response to FHP.At maximum FHP masticatory muscles tensity（/tone） rise, and EMG activities increase.