[The relative role of hereditary and environmental factors in the formation of the maxillodental system].

The contribution of hereditary and environmental factors to the formation of maxillodental abnormalities in the ontogenetic aspect was analyzed using a twin model. A total of 80 twin pairs aged 3 to 18 were examined. The results permitted the authors define the age periods favorable for therapeutic and prophylactic measures in children with abnormalities of the teeth, dentition, and occlusion. Effects of sex dimorphism on the parameters of the maxillodental system at various stages of ontogenesis were studied. Sex-specific differences were found to augment with age; all the analyzed parameters in boys were superior to those in girls at the age when sex-specific factors completely exerted their effects on the maxillodental system at the period of permanent teeth occlusion.