【作者】 刘莹；

【导师】 郭杰；

【作者基本信息】 山东大学 ， 口腔医学（专业学位）， 2023， 硕士

【摘要】 目的:微种植体辅助快速扩弓(microimplant-assisted rapid palatal expansion,MARPE)是矫治生长发育高峰期后患者上颌横向发育不足(maxillary transverse deficiency,MTD)的常用方法,多项研究推测MARPE疗效可能与颅面结构差异有关,本研究使用几何形态测量学(geometric morphometrics,GM)初步探究面中部形态差异与MARPE疗效的相关性,以期提高诊断精确性,辅助判断MARPE治疗效果,从而为治疗方案选择提供参考。方法:选取于山东大学口腔医院正畸科接受MARPE治疗的患者44例(平均年龄22.7±5.8岁),治疗前及扩弓保持3个月时拍摄CBCT。为衡量MARPE疗效,定义上颌骨基骨扩弓量与螺旋扩弓器激活量的比值为上颌基骨扩弓率(maxillaryexpansionratio,MER),并根据MER将44例患者分为高效、低效两组。随后使用GM进行面中部形态学分析,将患者面中部分为颞骨颧突、颧骨、鼻旁、牙槽突四个区域分别进行界标点和半界标点的放置和数字化,通过广义普氏分析提取面中部形状信息,采用普氏方差分析探究治疗前高、低效两组患者的面中部平均形状、平均尺寸是否存在差异,利用主成分分析揭示形状差异的主要来源,最后评估面中部尺寸差异对形状分析过程的影响。结果:1.本研究中上颌骨性扩弓成功率为90.9%,患者MER不符合正态分布,平均值为39.77±20.99%(范围 2.88%-94.33%,中位数 35.85%)。2.高、低效两组患者颞骨颧突、颧骨、鼻旁、牙槽突区域均不存在尺寸差异(P>0.05)。3.高、低效两组患者颞骨颧突区域存在显著形状差异(P<0.05),第一、第二主成分分别可代表所有形状差异的39.37%和15.03%,第一主成分与颧突长度有关,第二主成分与颧突的粗细和弯曲度有关,即高效组患者颧突更为细长、弯曲度更小。4.颧骨、鼻旁区域的形状差异与尺寸显著相关(P<0.01;P<0.001),而高、低效两组间颧突形状差异与尺寸无关(P>0.05)。结论:1.生长发育高峰期后患者MARPE疗效与面中部形态尤其是颞骨颧突形状存在相关性,颧突细长、生理性曲度小者可能获得较好的骨性扩弓效果,其中与颧突长度关系最为密切。2.生长发育高峰期后患者MARPE疗效和颧骨、上颌骨形状无关。3.生长发育高峰期后患者MARPE疗效与患者颧突、颧骨、上颌骨尺寸无关。更多还原

【Abstract】 Objectives:Microimplant-assisted rapid palatal expansion(MARPE)is an effective technology to correct the maxillary transverse deficiency(MTD)in patients with advanced bone maturation.Studies have shown that the MARPE effectiveness may be related to differences in craniofacial structures.This project intended to preliminarily investigate the correlation between the midfacial morphology and the MARPE effectiveness by geometric morphometrics(GM).And to improve the accuracy of diagnosis,assist in judging the effect of MARPE,and provide guidance for the selection of treatment objectives.Materials:CBCT scans of 44 subjects(22.7±5.8 years)treated with MARPE at the Department of Orthodontics,Stomatology Hospital of Shandong University were obtained before and after treatment.The maxillary expansion ratio(MER)was defined as the ratio of maxillary expansion width to the MARPE jackscrew expansion width and it was used to evaluate the MARPE effectiveness.The subjects were divided into two groups by the MARPE effectiveness:the high maxillary expansion ratio(HMER)group and the low maxillary expansion ratio(LMER)group.Landmarks and semi-landmarks were digitized on mid-face by four aspects of the morphology:zygomatic process,zygomatic bone,nasal and alveolar dataset.Generalized Procrustes analysis and principal component analysis were performed to remove information other than shape and reveal the main patterns of shape variation.The shape and size differences between the two groups were analyzed by Procrustes analysis of variance,respectively.The influences of size differences on shape analysis were evaluated finally.Results:1.The success rate of the MARPE treatment in this study was 90.9%.The maxillary expansion ratio did not conform to a normal distribution.The mean value of the maxillary expansion ratio was 39.77%±20.99%(range:2.88%-94.33%,median:35.86%).2.There were no statistical size differences between the HMER and LMER group in each dataset(P>0.05).3.A statistical difference was found in the shape of zygomatic process between the two groups(P<0.05).The principal component 1(PC1)explained 39.37%of the total variance and showed variability was mainly manifested in the length of the zygomatic process,which described the most crucial variance statistical difference in the shape of the zygomatic process.The principal component 2(PC2)explained 15.03%of the total variance and showed variability was mainly manifested in the diameter and the curvature of the zygomatic process.Subjects in the HMER group presented slender and straight zygomatic processes.4.The shape of the zygomatic bone and nasal region was correlated with the size(P<0.01;P<0.001).The shape variation of the zygomatic process was independent of size,thus,the shape differences between groups were not due to differences in size(P>0.05).Conclusions:1.Mid-facial morphology,especially the shape of the zygomatic process may influence the MARPE effectiveness in patients with advanced bone maturation.Patients with long,slender and straight zygomatic processes may be prone to have a better effect of MARPE.2.The shape of the zygomatic bone and the maxilla were not correlated with the MARPE effectiveness.3.The size of the zygomatic process,zygomatic bone and maxilla were not correlated with the MARPE effectiveness.更多还原