功能矫治器治疗儿童下颌后缩的颜面美学变化

Relationship between changes of facial soft tissue and hard tissue profile in correction of children's mandible retruding by functional appliance

目的 分析经Activator、Frankel等功能矫治器治疗后的安氏Ⅱ类 1分类下颌后缩患者 ,面部侧貌软组织的变化量及其与颌面部硬组织变化的相关性 ,以揭示下颌前伸后引起颜面美观变化的因素。方法 选取生长发育高峰期下颌后缩患者 32例 ,采用Activator、Frankel等功能矫治器矫治至磨牙达中性或中性偏近中关系 ,前牙覆盖 <4mm。采用Holdaway、Pancherz等方法 ,分析矫治前后X线头侧位片上的软硬组织变化量 ,并进一步分析它们之间的相关关系。结果 除了面角和上唇基厚度 ,下颌平面角 (MP SN)和上颌基骨位置 ,其余软硬组织指标治疗后都发生了明显变化 (P <0 .0 5 ) ;下列软硬组织的变化存在相关性 :唇颏高和后面高 (r =0 .5 4 ) ,颏部软组织厚度和前上面高 (r =0 .5 5 ) ,上唇长度和下切牙位置 (r=0 .5 2 ) ,颏唇沟深度和下切牙 (r =0 .6 0 )、下颌基骨的矢状位置及上下基骨的矢状关系 (r =0 .4 7)相关。结论 功能矫治器矫治安氏Ⅱ类 1分类错牙合 ,明显改善了患者的颜面美观 ,而软组织侧貌的变化 ,主要源于下切牙位置的改变、下颌前伸及由此引起的面高和上下颌骨矢状关系的改变。

Objective To evaluate the changes of soft tissue and hard tissue in the correction of Class II division 1 malocclusion by functional appliance, and to investigate the correlation between these changes and the mechanism underlying the soft tissue profile changes. Methods A total of 32 cases of developing class II division 1 malocclusion were selected. They were in the spurt or pre-spurt phase of growth and development and treated with functional appliance, the molar relationship was corrected to either Class I or overcorrected Class I occlusal relationship. Soft tissue and hard tissue variables on the cephalograms were selected and analyzed. Firstly, paired t-tests were performed to compare the changes between before and after-treatment. Secondly, those variables that had statistically significant differences were selected and analyzed with the Pearson coefficient of correlation (r) between soft tissue and hard tissue changes. Results All variables had statistically significant differences between before and after treatment except for soft tissue facial angle and basic upper lip thickness, mandible plane angle and position of basic upper bone; Correlations between soft tissue and hard tissue changes were as follows: height of lower lip to Me' and S-Go (r=0.54); soft tissue chin thick and N-ANS (r=0.55); height of upper lip and ii/OLp (r=0.52); inferior sulcus to H-line and ii/OLp (r=0.60), pg/OLp, saggital relationship between upper-and lower-jaw (ss/OLp-pg/OLp) (r=0.47). Conclusion The changes of soft tissues profile results from the change of lower incisors' position, mandible' moving forward and its subsequent changes of facial heights and saggital relationship between upper-and lower-jaws.