TI : Radiologic study of mandibular third molar of Korean youths
AU : Ahn HK
AD : Dept. of Oral Radiology, College of Dentistry, Seoul National University
SO : JKAMFR. 1982;12(1):57-61
ISSN : 1225-049X
LA : KOREAN
CP : KOREA
AB : The author has made a study on the classification of the mandibular 3rd molars of Korean youths through dental radiography by means of Pell & Gregory's classification and on the prevalence of the dental caries of distal surface of the mandibular 2nd molar adjacent to the mandibular 3rd molars turned anteriorly.
The results are as follow;
1. It was found that the largest case number was class I (272 cases, 52.9%) in the relation of the tooth to the ramus of the mandible and 2nd molar.
2. The mesio-angular position was the largest number (239 cases, 46.5%) in the relation of the long axis of the impacted mandibular 3rd molar to the long axis of the 2nd molar.
3. The mesio-angular position of class I was the largest number (140 cases, 27.2%) in the relation of the tooth to the ramus of the mandible and 2nd molar and the long axis of the impacted mandibular 3rd moral to the long axis of the 2nd molar.
4. The average angle of the long axis of mandibular 3rd molar in mesioangular position or horizontal position to the occlusal plane was 143 W
5. Mandibular 3rd molar with lesion such as dental cries or pericoronitis was 73 cases (14.2).
6. The caries incidence rate of the distal surface of the 2nd molar was about 3.1%.