title: Craniofacial structure related to inheritance pattern in amelogenesis imperfecta.
abstract: The aim of this study was to investigate the craniofacial structure in 66 children and adolescents, 34 girls and 32 boys, with known clinical manifestations and inheritance patterns for amelogenesis imperfecta (AI), and to compare the results with those obtained in a control group of age and sex matched persons with normal occlusion. The ages ranged from 6.8 to 21.2 years. Clinically, AI was divided into cases characterized by either hypoplasia or hypomineralization of the enamel. In a further subgrouping, eight clinical variants were diagnosed. Measurements of 12 angular and 15 linear, parameters on lateral cephalometric radiographs were included in comparisons between the AI and the control group. Compared with the control group, the AI group displayed statistically significant differences indicating a skeletal open bite. In the analysis of inheritance patterns and clinical manifestations, a skeletal open bite was associated with autosomal dominant (AD) and X-linked inheritance, and in the AD group with hypomineralization. When all cases except those with X-linked inheritance were pooled, deviations indicating a skeletal open bite were found in the subgroups "rough hypoplastic AI" and "hypomineralization AI." Since a skeletal open bite was found both with X-linked inheritance and in some of the subgroups connected with autosomal inheritance, the hypothesis of a pleiotropic gene effect as the cause of the simultaneous occurrence can be ruled out. The influence of modifying genes or environmental factors is suggested.
authors.affiliation: Department of Pedodontics, Faculty of Odontology, University of Umeå, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Bäckman
authors.forename: U
authors.initials: U
authors.lastname: Adolfsson
mesh_terms: D000293:Adolescent; D000567:Amelogenesis Imperfecta / Q000150:complications / Q000235:genetics* / Q000473:pathology; D016022:Case-Control Studies; D002508:Cephalometry; D002648:Child; D003743:Dental Enamel / Q000002:abnormalities; D003744:Dental Enamel Hypoplasia / Q000209:etiology / Q000235:genetics; D005260:Female; D005799:Genes, Dominant; D005808:Genes, Recessive; D008040:Genetic Linkage; D005838:Genotype; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000209:etiology* / Q000235:genetics; D008334:Mandible / Q000002:abnormalities*; D063173:Retrognathia / Q000209:etiology* / Q000235:genetics; D014074:Tooth Calcification; D014716:Vertical Dimension; D014960:X Chromosome