Hirai Shinya, Ogawa Takumi, Shigeta Yuko, Ando Eriko, Hirabayashi Rio, Ikawa Tomoko, Kasama Shintaro, Fukushima Shunji, Matsuka Yosizo
Department of Fixed Prosthodontics, Tsurumi University School of Dental Medicine, Tsurumi university, Yokohama, Japan.
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 Nov;108(5):e75-81. doi: 10.1016/j.tripleo.2009.07.008.
The aim was to report the kinetics of masticatory muscles using a 4-dimensional muscle model and kinetically investigate the etiology of square mandible (SQM) in vivo.
To ascertain the mandibular movements in patients with SQM, we compared a group of 11 SQM patients with painless limited mouth opening to a matched group of 11 healthy volunteers who acted as control subjects. Mandibular movements were recorded using a 6-degrees-of-freedom jaw-tracking device, with the incisal and kinematic condylar as analytic points.
For the control group, mean tracking distance for the incisal point was 50.1 +/- 6.8 mm, whereas for the SQM group mean tracking distance was 27.1 +/- 2.8 mm. With lateral excursions, the control group's mean tracking distance of the incisal point was 9.9 +/- 2.01 mm, and the SQM group's was 8.1 +/- 1.64 mm.
Despite a sufficient lateral excursion, motion of the mandible was limited by some factors at opening and suggests that the mode of lateral movements in SQM patients may differ slightly from those in healthy individuals.
旨在使用四维肌肉模型报告咀嚼肌的动力学，并在体内对方形下颌骨（SQM）的病因进行动力学研究。
为确定SQM患者的下颌运动情况，我们将一组11名患有无痛性张口受限的SQM患者与一组11名健康志愿者（作为对照对象）进行了比较。使用六自由度颌骨跟踪装置记录下颌运动，以切牙点和髁突运动点作为分析点。
对照组切牙点的平均跟踪距离为50.1±6.8毫米，而SQM组的平均跟踪距离为27.1±2.8毫米。在侧方运动时，对照组切牙点的平均跟踪距离为9.9±2.01毫米，SQM组为8.1±1.64毫米。
尽管有足够的侧方运动，但下颌骨在开口时的运动受到某些因素的限制，这表明SQM患者的侧方运动模式可能与健康个体略有不同。
