唇腭裂患儿下颌骨三维稳定结构的探索:从8岁到12岁

The stable mandibular structures in three-dimensions in cleft lip and/or palate patients aged from 8 to 12 years

目的 探索下颌骨生长发育过程中相对稳定的三维结构,为下颌骨的三维重叠提供依据.方法 样本由17例唇和/或腭裂术后患者组成,每位患者都有两个CT影像资料,两次CT拍摄间隔平均3.7年,患者首次拍摄CT年龄(8.7±0.8)岁(T1),末次拍摄年龄为(12.4±1.5)岁(T2).经过统一头位校正后,进行定点测量.标志点包括颏部的Pog,下颌联合内侧骨皮质的C、D和E点,颏孔前缘点MFA,颏孔点MF以及下颌孔点MdF.测量C点到以上所有标志点的距离,分析距离的变化来评价标志点的稳定性.同时,我们评价了标志点定点的可重复性.结果 从T1到T2,C到D、E及Pog的距离变化均值均<0.30 mm,标准差<0.62 mm,差异没有统计学意义,这4个点的定点在三维方向上都具有很好的一致性(克伦巴赫α>0.98);C点到左右侧颏孔的距离分别变化了(0.99±1.00) mm和(0.93±1.16) mm;C点到左右侧下颌孔的距离分别变化了(5.48±1.70) mm和(5.14±2.23) mm;颏孔间宽度和下颌孔间宽度分别增加了(1.21±1.06) mm和(4.06±1.31)mm.结论 从8.7到12.4岁,颏前点和下颌联合内侧骨皮质下部相对稳定.下颌神经管在此期间发生了变化,颏孔处的生长量较小,下颌孔处在横向和矢状向都有明显的生长变化.

Objective To identify the relatively stable mandibular structures in three dimensional (3D) images in growing patients,and to provide references for future three-dimension superimposition.Methods Measurements were made on two computed tomography (CT) scans taken about 3.7 years apart on each of 17 growing patients with cleft lip and/or palate aged from 8.7 (T1) to 12.4 years (T2).After head orientation,landmarks on the chin (Pog),internal symphysis (Points C,D and E),and mental foramina (MF and MFA) and mandibular foramina (MdF) were located.The linear distance change between Point C and these landmarks was measured on each CT to test stability through time.The reliability of the suggested stable landmarks was also evaluated.Results The total mean distance changes between Point C and points D,E,Pog were all less than 0.30 mm (SD <0.62 mm) from T1 to T2,which was not statistically significant.All four landmarks showed good consistency (α>0.98).Between T1 and T2,the distance changes from Point C to the left and right mental foramina were (0.99±1.00) mm and (0.93±1.16) mm (P<0.05),respectively,while the distance changes from Point C to the left and right mandibular foramina were (5.48±1.70) mm and 5.14±2.23 mm,respectively.The width of the mental foramen increased by (1.21±1.06) mm (P<0.05),and the width of the mandibular foramen increased by (4.06±1.31)mm (P<0.05).Conclusions From age 8.7 to 12.4 years old,Pog and landmarks on the inferior part of the internal symphysis appear relatively stable.Changes are observed in mandibular canal,with the least growth at mental foramina,and significant changes in the transverse and sagittal dimensions at mandibular foramina.