The Relation Ship Between the Changes of Facial Form and the Changes of Lip Pressure of Pre-and Post-Orthodontic Treatment.

本研究的目的是评估正畸治疗前后牙位变化、面部形态变化和唇压之间的关系。讨论了云纹形貌在人脸三维评价中的可靠性和测量精度，表明该方法适用于人脸分析。本研究中使用的设备是使用电阻应变片的压力传感器。得到了以下结果：前交叉咬合患者治疗前唇形与下门牙位置的关系。但在治疗后，唇形与上门牙的位置有关。治疗后的上唇压力比治疗前有增大唇压的趋势，而下唇压力比治疗前有增大唇压的趋势。正畸手术治疗中软组织的变化与硬组织的变化高度相关。治疗后上唇压力较治疗前升高，下唇压力较治疗前降低。本研究表明，唇压是造成牙弓形成的因素之一，正畸治疗后的牙位或牙弓在功能上与新的口腔状况相适应。

The purpose of this study is to evaluate the relationship among the changes of tooth position, the changes of facial form and lip pressure of pre-and post-orthodontic treatment. The reliability and measurement accuracy of moire topography in three dimensional assessment of the human face were discussed and this method appeared to be suitable to analyze the face. The devices employed in this study were pressure transducers using resistance-strain gauges.The following results were obtained.1. The pre-treatment lip form related to the position of lower incisors in anterior cross bite patients. But in post-treatment the lip form related to the position of the upper incisors. The upper lip pressure of post-treatment showed a tendency of higher labial pressure than the pre-treatment, but lower lip pressure of the post-treatment showed a tendency of lower labial pressure than the pre-treatment.2. The changes of the soft tissues were highly correlated with the changes of hard tissues in surgical orthodontic treatment. In post-treatment Upper lip pressure increased and lower lip pressure decreased than the pressure of pre-treatment.This study demonstrated that the lip pressure was one of the factors of making the dental arch form, and the tooth position or the arch form after orthodontic treatment functinally suitable to the new oral conditions.