Abstract
INTRODUCTION: The inheritance of class III malocclusion has been well documented, but the inheritance of craniofacial structures in Colombian families with this malocclusion has been not yet reported. PATIENTS AND METHODS: The study sample of 25 families comprised 186 untreated orthodontic individuals from 8 to 60 years old. Pedigrees were drawn using Cyrillic software. Complete family histories for each proband were ascertained and the affection status of relatives was confirmed by lateral cephalograms and facial and dental photographs. Analysis of variance and odds ratio test for each parameter was performed to estimate inheritance from parents to offspring and to determine similar phenotypic features in relatives. RESULTS: The analysis of the pedigrees suggests autosomal dominant inheritance. The craniofacial characteristics that showed more resemblance between parents and offspring were middle facial height, shorter anterior cranial base and mandibular prognathism. In contrast the protrusion of upper lip and maxillary retrusion were the phenotypic features that contributed to class III in the majority of families. CONCLUSION: Knowledge of the inheritance of craniofacial phenotypes in class III malocclusion will enable the design of new therapies to treat this malocclusion.