不同年龄段Ⅲ类偏颌患者髁突位置和下颌骨形态的锥形束CT研究

A cone beam computed-tomography study on condylar position and mandibular morphology of skeletal ClassⅢpatients with mandibular deviation in different ages

目的通过对不同年龄组骨性Ⅲ类伴下颌偏斜患者髁突位置和下颌骨形态的研究,探讨各年龄组该类患者下颌偏斜特征,为下颌偏斜患者的鉴别诊断及治疗提供参考。方法选择骨性Ⅲ类伴下颌偏斜患者34例(未成年和成年人各17例),术前拍摄锥形束CT,采用三维测量软件对骨组织进行三维重建,测量分析:关节间隙、髁突、下颌升支、下颌体的相关指标。结果髁突位置:未成年人组左右髁突-关节窝的相对位置[偏斜侧:(-1.15±11.99),对侧:(7.58±12.92)]差异有统计学意义(P<0.05),偏斜侧髁突相对靠后,对侧相对靠前。下颌骨形态:未成年人组下颌体长度[偏斜侧:(85.05±7.06)mm,对侧:(88.01±5.89)mm]、下颌骨总长度[偏斜侧:(121.82±9.69)mm,对侧:(127.55±9.53)mm]、下颌角[偏斜侧:(123.45±3.91)°,对侧:(125.19±4.21)°]的测量项目,对侧>偏斜侧(P<0.01);成年人组髁突高度[偏斜侧:(16.98±2.51)mm,对侧(19.10±2.43)mm]、髁突内外径[偏斜侧:(18.01±2.69)mm,对侧:(19.56±1.80)mm]、下颌升支高度[偏斜侧:(55.63±4.14)mm,对侧:(59.49±5.22)mm]、下颌体长度[偏斜侧:(92.06±5.52)mm,对侧:(93.59±5.87)mm]、下颌骨总长度[偏斜侧:(131.68±6.66)mm,对侧:(137.75±6.36)mm]、下颌角[偏斜侧:(123.92±6.18)°,对侧:(125.94±5.55)°]的测量项目,对侧>偏斜侧(P<0.05),其余项目两组间差异无统计学意义(P>0.05)。结论骨性Ⅲ类伴下颌偏斜患者,未成年人以左右髁突位置不对称为主,成年人以双侧颌骨形态不对称为主。

Objective The aim of this study was to investigate condylar position and mandibular morphology of skeletal ClassⅢpatients with mandibular deviation in different ages,and to provide a reference for clinical differential diagnosis and treatment plan.Methods Thirty-four skeletal ClassⅢpatients with mandibular deviation were divided into the adolescent group(17 cases)and the adult group(17 cases).Cone beam CT scans of all the patients were obtained before treatment.Invivo Dental 5 was used to reconstruct the bone tissues.Joint space the relevant indicators about condyle、mandibular ramus and mandibular body were analyzed.Results Condylar position:there was a statistical difference between the relative position of each side of condyle-articular fossa[the deviation side:(-1.15±11.99),the opposite side:(7.58±12.92)](P<0.05)in the adolescent group;the deviated side was relatively posterior while the contralateral side was relatively anterior.Mandibular morphology:in the adolescent group,there were significant differences between each side in the measurements of mandibular body length[the deviation sides:(85.05±7.06)mm,the opposite sides:(88.01±5.89)mm],total mandible length[the deviation sides:(121.82±9.69)mm,the opposite sides:(127.55±9.53)mm],and the angle of the mandible[the deviation sides:(123.45±3.91)°,the opposite sides:(125.19±4.21)°](P<0.01),in which the measurement of the opposite sides were all larger than the that of the deviation side.In the adult group,there were statistical differences between each side in the measurement of the height of condyle[the deviation sides:(16.98±2.51)mm,the opposite sides:(19.10±2.43)mm],the inner and outer diameter of the condyle[the deviation sides:(18.01±2.69)mm,the opposite sides:(19.56±1.80)mm],the height of mandibular ramus[the deviation sides:(55.63±4.14)mm,the opposite sides:(59.49±5.22)mm],the length of mandibular body[the deviation sides:(92.06±5.52)mm,the opposite sides:(93.59±5.87)mm],the total mandible length[the deviation sides:(131.68±6.66)mm,the opposite sides:(137.75±6.36)mm],and the mandibular angle[the deviation sides:(123.92±6.18)°,the opposite sides:(125.94±5.55)°](P<0.05),in which all the opposite sides were larger than the deviation sides.The other measurements had no statistical difference(P>0.05).Conclusions The mandibular deviation in skeletal ClassⅢpatients is mainly from condylar position difference of each side in the adolescent group,while from mandibular morphological difference of each side in the adult group.