[A correlate study on the first cervical vertebra and mandibular growth:A comparison of Shanghai females between 12 and 15 years old]
OBJECTIVE:To study the correlation between the cervical vertebra and mandibular growth and to reveal the intrinsic rule of the progress of individual growth, especially the trend of craniofacial development.METHODS:The morphological features of the first cervical vertebra and certain variables of craniofacial in lateral cephalometric radiographs from Shanghai females between 12 and 15 years old were measured and correlated. A set of normal values of the atlas vertebra shape of Shanghai 12 and 15 years old females were established.RESULTS:There was a significant correlation between D1 and AP of the first cervical vertebra and the direction of mandibular growth at the age of 12. But the association between atlas size ratio (AP/D1) and the mandibular growth is more notable than either AP or D1. When the atlas size ratio increased, a reduction of the amount of mandibular horizontal growth was showed, and the mandibular rotated backward; on the contrary, when the atlas size ratio decreased, the amount of mandibular horizontal growth increased and the mandibular rotated forward. CONCLUSION: The first cervical vertebra can be used as an indicator to predict the mandibular growth.
Liu
H H
HH
Department of Orthodontic, School of Stomatology, Shanghai Second Medical University. Shanghai 200011, China.
Lin
H
H
Sun
Y
Y
Tao
L
L