成人骨性Ⅲ类偏颌患者颅底形态特征的三维研究

Three-dimensional analysis on morphology of cranial base in adults with skeletal classⅢmalocclusion and facial asymmetry

目的骨性Ⅲ类偏颌畸形是一种表现复杂、临床矫治困难的错牙合畸形,其发生发展一般受遗传与环境因素的共同影响。颅底作为颅面复合体的一部分,其与错牙合畸形的内在联系一直受到正畸学者的关注。本研究基于锥形束CT(CBCT)检测数据,以探索成人骨性Ⅲ类偏颌畸形患者颅底形态与颌面骨骼对称性的关系。方法选取成人骨性Ⅲ类偏颌患者及非偏颌者各40例,将其CBCT数据导入Mimics 21.0软件进行三维重建,测量相关指标。使用SPSS 26.0软件,分别对偏颌患者的偏斜侧与偏斜对侧各测量值进行配对t检验,对偏颌组及对照组两侧差值进行独立样本t检验。对颏部偏移量与各测量指标进行双变量相关分析。结果偏颌组颅底测量指标中,两侧GIS-L差异有统计学意义(P<0.05)。下颌骨测量指标中,两侧Co-H、Co-V、Co-Go、Go-Me、Co-Me差异有统计学意义(P<0.05)。对照组下颌骨测量指标中,两侧Co-V差异有统计学意义(P<0.05)。2.颅底测量指标中,偏颌组两侧Op-P差值,Cl-P差值、S-Cl-P差值、GIS-L差值与对照组差异有统计学意义(P<0.05)。颌骨测量指标中,偏颌组两侧Co-A差值、Co-V差值、Co-Go差值、Go-Me差值、Co-Me差值、Me-MSP与对照组差异有统计学意义(P<0.05)。3.偏颌组中,Me-MSP与S-Cl-P差异、Co-Me差异呈正相关(P<0.05)。结论成人骨性Ⅲ类偏颌患者中颅窝、岩嵴、关节窝及下颌骨形态不对称。其下颌偏斜程度与两侧中颅窝角度差异呈正相关,也与两侧下颌全长差异呈正相关。除下颌骨自身不对称发育外,下颌偏斜还可能与中颅窝的不对称发育有关。

Objective Skeletal class III malocclusion has always been a complicated and a difficult subject in orthodontics.Its occurrence and development were generally affected by both genetic and environmental factors.As a part of the craniofacial complex,the inner correlation of the skull base and craniofacial deformities has always been concerned by orthodontists.Based on the statistics of the cone beam computed tomography(CBCT)the purpose of the study was to analyze the relationship between cranial base and mandibular in adults with skeletal class III malocclusion and facial asymmetry.Methods Patients were divided into two groups-the skeletal classⅢmalocclusion group with facial asymmetry and the skeletal classⅢmalocclusion group with non-facial asymmetry.Each group had 40 patients.The data of CBCT were imported into Mimics 21.0 software to measure related variables.Using SPSS 26.0 software,all measurements were compared between the deviated and non-deviated sides were analyzed with student t test in the asymmetry group.And differences between skeletal ClassⅢasymmetry group and symmetry group were compared with paired t test.The correlation between mandibular deviation and other variables were performed in the skeletal ClassⅢasymmetry group.Results①In cranial base variables,there were significant differences between the deviated side and the non-deviated side in the GIS-L of asymmetry group.Considering about mandibular variables,there were significant differences between the deviated side and the non-deviated side in the Co-H、Co-V、Co-Go、Go-Me、Co-Me(P<0.05).In the symmetry group,there were significant differences in the Co-V between the deviated side and the non-deviated side(P<0.05).②In cranial base variables,there were significant differences between the asymmetry group and the symmetry group in the Op-P、Cl-P、S-Cl-P and GIS-L(P<0.05).In mandibular variables,there were significant differences between the asymmetry group and the symmetry group in the Co-A、Co-V、Co-Go、Go-Me、Co-Me、Me-MSP(P<0.05).③In our study,the Me-MSP were weakly positively correlated with the differences of middle cranial angle and the difference of Co-Me(P<0.05).Conclusion The middle cranial angle,the distance from Op to P、distance from Cl to P、length of articular fossa、height of condyle、volume of condyle、axial angle of condyle、length of mandibular ramus、length of mandibular body、length of mandible were asymmetrical in patients with skeletal classⅢmalocclusion and facial asymmetry.The degree of mandibular deviation was positively correlated with the differences of middle cranial angle and the length of mandible on both sides.In addition to the asymmetrical development of the mandible itself,mandibular deviation may be related to the asymmetrical development of the middle cranial fossa.