齒牙硬組織의 異常에 關한 調査 : Part Ⅰ- Variation in number = A Study of Dental Anomalies of Ewha Womans University Students in Korea

다국어 초록 (Multilingual Abstract)

A study of congential dental anomalies was done through annual examination of Ewha Womans University students in Korea. Data of 5,354 students, aged 18-22 years, were collected and analyzed for this project.
Variations in number, variation in size, fusion, and anomalies in tooth position were included in the study. Among them, the variation in number-anodontia-were very interesting and made an article here.
The frequency of congenitally missing permanent teeth of this study were quite different from other reports, especially from European and American studies. That is, Oriental origin in its pattern of the missing was considerably diferent from them. And racial differences were found even a little.
Supernumerary tooth and fusion were checked and recorded in addition to them.
A statistical report of variation in number is very significant to understand the dental status of Korean college girls, particularly to understand the practical missing teeth in DMF teeth of them.
The cause of tooth loss in this student group would be the next project as a serial study.
The findings of this study have be summarized as follows:
1. The prevalance of congenitally missing teeth was 6.6%(N=347).
2. The order of frequency of congenitally missing teeth was lower lateral incisors (23.4%), upper lateral incisors (17.1%), lower second bicuspids (14.8%), and upper second bicuspids (14.6%), while the European studies reported as upper lateral incisors and upper second bicuspids and lower second bicuspids and so on. An the Japanese one was similar with this data. Lower canines was revealed the lowest frequency of congenitally missing teeth. The average was 1.6 teeth per head. (N=561).
3. There were no significant differences between upper and lower nor right and left teeth.
4. 145 retained deciduous teeth instead of permanent teeth are found occuring in 561 cases of congenitally missing teeth (25.8%).
5. Supernumerary teeth were checked in only 23 cases on the maxillary except two cases on mandible.
6. Fusions were found in only 13 cases on mandibular anteriors except one case on a maxillary anterior. The prevalance was 0.2%.

목차 (Table of Contents)

• Ⅰ. 緖論
• Ⅱ. 調査對象 및 方法
• Ⅲ. 調査結果
• 1. 齒牙의 先天的缺如
• 2. 過剩齒
• 3. 癒合齒
• Ⅳ. 考按
• Ⅴ. 結論
• 參考文獻