成年女性骨性Ⅱ类高角错[牙合]患者拔牙掩饰治疗后软组织颏部突度变化的影响因素研究

Study on the soft mental protrusion changes in adult female patients with skeletal classⅡhigh-angle malocclusion after camouflage treatment

目的探究影响成年女性骨性Ⅱ类高角错[牙合]患者拔牙掩饰治疗后软组织颏部突度变化的软硬组织因素以及治疗前后的硬组织变化规律,为其疗效评估和矫治设计提供参考。方法选取2017年1月至2020年10月于四川大学华西口腔医院正畸科完成拔牙掩饰治疗的成年女性骨性Ⅱ类高角错[牙合]患者48例,依据治疗前后头颅侧位片上软组织颏前点(Pos)矢状向的位移量将患者分为Pos后移组和Pos前移组,测量2组治疗前后的牙性、骨性及软组织指标。比较2组治疗前各项指标差异,以及各组治疗前后的硬组织指标变化。结果治疗前2组下颌中切牙矢状向位置(L1-H)、下颌第一磨牙近远中倾斜度(L6-MP)、上下唇及软组织颏部矢状向位置(UL-H、LL-H、Pos-H)比较,差异有统计学意义(均P<0.05)。Pos前移组治疗前后上下颌骨矢状向位置关系(ANB)、下颌平面角(MP-SN)、上下颌中切牙矢状向位置(U1-H、L1-H)及上下颌第一磨牙矢状向位置(U6-H、L6-H)、上下颌中切牙唇舌向转矩(U1-SN、L1-MP)、下颌第一磨牙近远中倾斜度(L6-MP)、上颌中切牙和上颌第一磨牙及下颌第一磨牙近中颊尖垂直向位置(U1-V′、U6d-V′、U6m-V′、L6m-V′)比较,差异均有统计学意义(均P<0.05);而治疗前后上下牙槽座角(SNA、SNB)及上颌第一磨牙近远中倾斜度(U6-SN)比较,差异均无统计学意义(均P>0.05)。Pos后移组治疗前后SNA、SNB、U1-H、L1-H、U1-SN、L1-MP、上下颌第一磨牙近远中倾斜度(U6-SN、L6-MP)及下颌中切牙垂直向位置(L1-V′)比较,差异均有统计学意义(均P<0.05);而治疗前后ANB、MP-SN、U6-H及L6-H比较,差异无统计学意义(均P>0.05)。结论在成年女性骨性Ⅱ类高角错[牙合]患者中,下颌中切牙、上下唇及软组织颏部更前突,以及下颌第一磨牙近中倾斜程度更大者,可能更难通过拔牙掩饰治疗获得软组织颏部的前移。成年女性骨性Ⅱ类高角错[牙合]患者拔牙掩饰治疗可以更加精细地控制前牙内收量、磨牙近移量、前牙唇舌向转矩、磨牙近远中倾斜度以及上下颌前、后牙的压低量,从而尽可能达到软组织颏部的前移,更大程度改善患者侧貌。

Objective To explore the soft and hard tissue factors that affect the change of chin protrusion and the change rule of hard tissue before and after treatment in adult female patients with skeletal classⅡhigh-angle malocclusion who have completed tooth extraction camouflage therapy,and to provide reference for the efficacy evaluation and treatment design.Methods A total of 48 adult female patients with skeletal classⅡhigh-angle malocclusion who had completed tooth extraction camouflage therapy were selected.According to the sagittal change of the pogonion of soft tissue(Pos)on the lateral radiographs before and after treatment,the samples were divided into Pos backward shift group and Pos forward shift group.Measure the dental and skeletal indexes of the two groups and compare the differences of each index between the two groups before treatment,as well as the changes of hard tissue index before and after treatment in each groups.Results Before treatment,the sagittal position of mandibular central incisors(L1-H),the mesial and distal inclination of mandibular first permanent molars(L6-MP),the sagittal position of upper,lower lips and soft chin(UL-H,LL-H,Pos-H)were significantly different between the two groups(P<0.05).There were significant differences in the sagittal position relationship of maxilla and mandible(ANB),the mandibular plane angle(MP-SN),the sagittal position of upper and lower central incisors and first permanent molars(U1-H,L1-H,U6-H,L6-H),the labial and lingual torque of upper and lower central incisors(U1-SN,L1-MP),the mesial-distal inclination of mandibular first permanent molars(L6-MP),and the vertical position of upper central incisors,upper first permanent molars and the mesiobuccal cusp of lower first permanent molars(U1-V′,U6d-V′,U6m-V′,L6m-V′)in Pos-forward group before and after treatment,while there were no significant differences in the upper and lower alveolar angle(SNA,SNB)or the mesial-distal inclination of maxillary first permanent molars(U6-SN)(P>0.05).There were significant differences in SNA,SNB,U1-H,L1-H,U1-SN,L1-MP,U6-MP,L6-MP and U1-V′of the Pos-backword group before and after treatment(P<0.05),while there were no significant differences in ANB,MPSN,U6-H or L6-H(P>0.05).Conclusion For adult female patients with skeletal classⅡhigh-angle malocclusion,with more protruding lower central incisors,lips and soft tissue chin,and more mesial inclination of mandibular first permanent molars,it may be more difficult to obtain absolutely forward soft chin through orthodontic camouflage therapy.The orthodontic camouflage therapy may obtain the absolute forward soft tissue chin,so as to improve the patients′profile by controlling more carefully the amount of the anterior teeth retraction,mesially movement of the molars,the torque of the anterior teeth,the mesio-distal inclination of the molars and the amount of the anterior and posterior teeth intrusion.