Laatikainen T, Ranta R, Nordström R
Department of Pedodontics and Orthodontics, University of Helsinki, Finland.
Cleft Palate Craniofac J. 1996 Mar;33(2):96-103. doi: 10.1597/1545-1569_1996_033_0096_cmitwc_2.3.co_2.
The craniofacial morphology of 11 pairs of monozygotic (MZ) and 28 pairs of dizygotic (DZ) Finnish twins, discordant or concordant for cleft of the lip (CL), unilateral cleft lip and palate (UCLP), or cleft palate only (CP) were investigated by means of lateral cephalometric radiographs. The results were compared to those of age-, sex-, and cleft-type matched single-birth cleft subjects, and also with normative data from the Nordic population. The co-twins with no cleft lip or palate (NONC) showed only slightly more obtuse gonial and steeper mandibular angles compared to normative data. Twins with CL, UCLP or CP had a more retrusive mandible, a wider cranial base and mandibular angle, and a wider angle between the maxilla and mandible than did the single-birth cleft subjects. Comparison of the noncleft twin group with the CL, UCLP, and CP twin groups for the CL twins showed no significant differences. For the UCLP twins, a more retrusive and down- and backward rotation of both jaws, a wider gonial angle, and a wider cranial base angle was seen. The CP twins had their maxillae slightly retrusive, the down- and backward rotation of both jaws was apparent, and the gonial angle was more obtuse. A comparison between the noncleft MZ and noncleft CDZ twins showed no significant differences. The MZ CP twins had a more retrusive mandible and more down- and backward rotation of both jaws than did DZ CP twins. It thus can be suggested that twinning itself does not seem to have an effect on maxillofacial morphology, but the features of the mandibular structure, the cranial base angulation, and the inclination of the jaws are at least partly genetically induced.
通过头颅侧位X线片对11对单卵（MZ）和28对双卵（DZ）芬兰双胞胎的颅面形态进行了研究，这些双胞胎在唇裂（CL）、单侧唇腭裂（UCLP）或仅腭裂（CP）方面存在不一致或一致的情况。将结果与年龄、性别和腭裂类型匹配的单胎腭裂患者的结果进行比较，同时也与北欧人群的正常数据进行比较。未患唇腭裂的双胞胎（NONC）与正常数据相比，仅表现出下颌角稍钝和下颌角更陡。与单胎腭裂患者相比，患有CL、UCLP或CP的双胞胎下颌更后缩，颅底和下颌角更宽，上颌与下颌之间的角度更宽。将非腭裂双胞胎组与CL、UCLP和CP双胞胎组进行比较，CL双胞胎组未显示出显著差异。对于UCLP双胞胎，观察到上下颌均更后缩且向下和向后旋转，下颌角更宽，颅底角更宽。CP双胞胎的上颌稍向后缩，上下颌向下和向后旋转明显，下颌角更钝。非腭裂MZ双胞胎和非腭裂CDZ双胞胎之间的比较未显示出显著差异。MZ CP双胞胎比DZ CP双胞胎下颌更后缩，上下颌向下和向后旋转更多。因此可以认为，双胞胎本身似乎对颌面形态没有影响，但下颌结构、颅底角度和颌骨倾斜度的特征至少部分是由遗传因素引起的。
