The Study of Eruption Process of the Permanent Teeth (First Permenent Molar)

Kim,  Jin-Tae

J Korean Dent Assoc > Volume 21(12); 1983 > Article

The Journal of The Korean Dental Association 1983;21(12):1005-1010.
Published online December 31, 1983.

영구치 맹출양상에 관한 연구(제1대구치)

김진태

서울대학교 치과대학 소아치과학교실

The Study of Eruption Process of the Permanent Teeth (First Permenent Molar)

Jin-Tae Kim

Dept. of Pedodontics, School of Dentistry, Seoul National University

Abstract

To study the eruption process of the permanent tooth, esp., 1st molar, the author took 303 cases of oblique cephalogram (Male. 162 cases, Female: 141 cases) from age 3 to 8 yea old children, and observed the vertical change and axial change. The result were as follow: 1. The mesial end of upper 1st molar was closer to the occlusal plane than the distal, and they were erupting toward the occlusal plane by aging. In the case of lower 1st molar, the distal end was closer to the occlusal plane than the mesial and the occlusion showed the tendency to accord with the plane to be settled by aging. 2. Eruption rate of the upper and lower 1st permanent molar increased rapidly at 5 or 6 years of age. 3. Axial inclination of lower 1st permanent molar to the mandibular plane decreased gradually from 3 years of age, except for 6 years of age. There was some increase at 5 or 6 years of age.