安氏Ⅰ类和Ⅱ类1分类错患者下颌位置的研究

Analysis of mandibular position of patients with Angles Class Ⅰ and ClassⅡ,Di vision 1 malocclusion

目的 研究错患者下颌处于正中关系位 (centricrelation ,CR)和最大牙尖交错位(maximumintercuspation ,MI)时髁突位置与咬合关系的变化。方法 使用Panadent架系统和髁突位置测量仪 ,检查 5 0名错患者 (安氏Ⅰ类、Ⅱ1类各 2 5人 )的下颌位置和咬合情况。结果 几乎所有患者均存在CR -MI髁突位置差异 ,在矢状方向上多为向后下移位。 65 %的受检者CR初始接触位于单侧最后磨牙。当下颌从CR位移至MI位时 ,咬合变化主要表现为磨牙关系近中化、切牙覆加深、覆盖变浅。安氏Ⅰ类与Ⅱ1类错之间 ,上述改变的差异无显著性。结论 正畸治疗前必须了解患者下颌处于正中关系时的咬合情况 ,发现与下颌位置之间的不协调。

Objective To study changes of condyle position and occlusion betw een centric jaw relation and maximum intercuspation positions. Methods The power centric registration advocated by Roth was used to take centric relation bite re gistration for 50 patients (25 Class I and 25 ClassⅡ,Division 1) and diagnosti c models were mounted and analysed with Panadent articulator and condyle positio n indicator. Results Nearly all patients had CR-MI difference s in all three planes of space. 70% of the sagittal displacement was within 2. 0 mm an d 87% of the transverse displacement was within 1.0 mm. Most of the condyles m ov ed posteriorly and inferiorly. 65% of the initial contacts in CR occured on the most posterior molar on single side. Correlation was found between some varia bles of condylar displacement and occlusion changes. No significant difference was observed in condylar position and occlusion changes between Class I and Clas sⅡ,Dvison 1 patients. Conclusions The occlusion in centric j aw relation should be analysed before treatment to reveal the disharmony between occlusion and jaw position.