Moriyama K, Motohashi N, Kitamura A, Kuroda T
Department of Orthodontics, The University of Tokushima, Japan.
Cleft Palate Craniofac J. 1998 Mar;35(2):173-80. doi: 10.1597/1545-1569-35.2.173.
In this study, we analyzed the craniofacial and dentoalveolar morphologies of three pairs of monozygotic twins discordant for cleft lip and/or palate (CL/P) in order to evaluate the effects of environmental factors on growth and development.
Craniofacial and dentoalveolar morphologies revealed by analyses of cephalograms and dental casts were compared for each pair of twins discordant for CL/P.
In case 1, the subjects were 10-year-old male twins, one of whom had a repaired unilateral cleft lip and alveolus and one of whom had an unrepaired unilateral cleft lip. In case 2, the subjects were 13-year-old female twins, one of whom had a repaired bilateral cleft lip and palate and one of whom had an unrepaired unilateral cleft lip. In case 3, the subjects were 9-year-old female twins, one of whom had a repaired unilateral cleft lip and palate and one of whom had no cleft.
Cephalometric analysis disclosed distinguished intrapair differences in the maxillary and mandibular morphologies in cases 2 and 3. However, the tooth axes of the incisors in operated subjects were consistently influenced in all three cases. Dental cast analysis indicated that the shapes and sizes of the alveolar and dental arches in the operated subjects were affected in case 2 and, more severely, in case 3, while they looked fairly similar in case 1.
Cephalometric and dental cast analyses demonstrated characteristic intrapair differences between the twins discordant for CL/P according to each cleft type. These morphological differences indicate that surgical closure of clefts may have considerable effects on craniofacial and dentoalveolar growth and development in CL/P patients.
在本研究中，我们分析了三对唇腭裂（CL/P）不一致的同卵双胞胎的颅面和牙-牙槽形态，以评估环境因素对生长发育的影响。
对每对CL/P不一致的双胞胎进行头影测量分析和牙模分析，比较所揭示的颅面和牙-牙槽形态。
病例1中，受试者为10岁男性双胞胎，其中一人单侧唇裂和牙槽突已修复，另一人单侧唇裂未修复。病例2中，受试者为13岁女性双胞胎，其中一人双侧唇腭裂已修复，另一人单侧唇裂未修复。病例3中，受试者为9岁女性双胞胎，其中一人单侧唇腭裂已修复，另一人无唇腭裂。
头影测量分析显示，病例2和病例3中上颌和下颌形态存在明显的双胞胎内差异。然而，在所有三个病例中，手术受试者的切牙牙轴均受到一致影响。牙模分析表明，病例2中手术受试者的牙槽弓和牙弓的形状和大小受到影响，病例3中影响更严重，而病例1中两者看起来相当相似。
头影测量和牙模分析表明，根据每种腭裂类型，CL/P不一致的双胞胎之间存在特征性的双胞胎内差异。这些形态学差异表明，腭裂的手术闭合可能对CL/P患者的颅面和牙-牙槽生长发育产生相当大的影响。
