Heritability of thirty cephalometric parameters on monozygotic and dizygotic twins: twin study method.

Genetic mechanisms are already predominant during embryonic craniofacial morphogenesis, but environment is also thought to influence dentofacial morphology postnatally, particularly during facial growth. A better understanding of the relative effects of genes and environment on dentofacial and occlusal parameters should improve our knowledge on the etiology of orthodontic disorders and therefore also on the possibilities and limitations of the orthodontic treatment and treatment planning. The aim of the present study is to explore the genetic and environmental influence on craniofacial dimensions in a group of 19 pairs of twins using the twin study method.

Objective evaluation of cervical vertebral bone age' its reliability in comparison with hand-wrist bone age: by TW3 method.

Aim: The aim of this study was to establish the validity of a new method for evaluating skeletal maturation by assessing the 3rd and 4th cervical vertebrae seen in the cephalometric radiograph.

Materials And Methods: This study consisted of a sample of 50 patients in the age group of 8 to 14 years of age. Chronologically, they were divided into six groups, based on the age consisting of a minimum of six to a maximum of 10 subjects.