安氏Ⅱ、Ⅲ类错畸形治疗后咬合关系与牙量比例的相关性研究

Connection between occlusal relationship and tooth-size discrepancy in Class Ⅱ and Class Ⅲ patients after orthodontic treatment

目的了解安氏Ⅱ1、Ⅱ2、Ⅲ类错畸形治疗后咬合关系与牙量比例的相关性。方法选择治疗结束的153例安氏Ⅱ、Ⅲ类错畸形患者的模型,利用PAR指数评分将患者分为咬合理想与咬合不理想两组,分别测量每一副模型Bolton全牙比值,根据其正常值得出两组样本牙量不调的比率并作统计学分析。结果治疗后咬合理想组Bolton全牙比值不调的占47.27%,而治疗后咬合不理想组Bolton全牙比值不调的占71.43%;治疗后咬合不理想组模型分类研究结果显示:牙量不调比率由大到小依次为安氏Ⅱ2类>安氏Ⅲ类>安氏Ⅱ1类,分别为85%、68.8%、66.7%。咬合不理想组全牙牙量不调明显高于咬合理想组,P=0.003,安氏Ⅱ2类全牙量不调发生率最高。结论上下牙量比例直接影响治疗后尖牙、双尖牙及磨牙的咬合关系的调整。

Objective To investigate the connection between occlusal relationship and tooth - size discrepancy in Class Ⅱ and Class m patients after orthodontic treatment. Methods One hundred and fifty - three dental casts of patients with Class Ⅱ and Class Ⅲ malocclusions were collected and divided into two groups according to PAR index scores. One group was the ideal occlusal relationship casts and the other was the non - ideal ones. The mesio - distal widths of the mandibular and maxillary 12 teeth （ first molar to first molar） were measured. Tooth - size discrepancy was statistically analyzed. Results Casts in patients with Bohon overall ratio discrepancy represented 47.27% in ideal occlusal relationship group while 71.43% in non -ideal occlusal relation group; In the non -ideal occlusal relationship group, the severity of tooth- size discrepancy was： Class Ⅱ^2 （85%） 〉 Class Ⅲ （68.8%）〉 Class Ⅱ^1 （66.7%）. Tooth- size discrepancy in the non - ideal occlusal relationship group was more severe than that in the ideal occlusal relationship group （ P = 0,003 ）. Tooth -size discrepancy was most severe in Class Ⅱ division 2 patients. Conclusion Tooth - size discrepancy directly affected the adjustment of occlusal relationship in cuspid, bicuspid and molar areas.