A STUDY ON CALCIFICATION OF THE SECOND MOLARS IN SKELETAL CLASS III MALOCCLUSIONS

골격형 III급 부정교합자의 제2 대구치 석회화과정에 관한 연구

  • Cha, Kyung Suk (Dept. of Orthodontics, Graduate School, Seoul National University)
  • 차경석 (서울대학교 대학원 치의학과 교정학)
  • Published : 1981.12.01

Abstract

This investigation was designed to compare the calcification degree of maxillary second permanent molar to mandibular second permanent molar in skeletal Class III Malocclusion. The material selected for this study consisted in standand lateral cephalogram study model and orthopantomogram of two hundred fifty seven Korean Children, one hundred twenty one boys and one hundred twenty four girls, aged 6 through 12 years, having skeletal Class III Malocclusion. On the basis of findigs of this study, the following results were obtained 1. In the stage of completion of crown, there was no significant difference in calcification degree between maxillary second molar and mandibular second molar of both boys and girls in skeletal Class III Malocclusion. 2. From 8 years of age at the stage of beginning root formation to 12 years of age, the calcification degree of mandibular second molar was more advanced than Maxillary second molar of both boys and girls in skeletal Class III Malocclusion.

Keywords