RADIOLOGRAPHIC STUDY OF MANDIBULAR THIRD MOLARS

하악 제3대구치의 X-선학적 연구

  • Ahn Hyung Kyu (Dept. of Oral Radiology, College of Dentistry Seoul National University)
  • 안형규 (서울대학교 치과대학 치과방사선학교실)
  • Published : 1986.12.01

Abstract

The author performed radiographical analysis of the third molar dentition and characteristic relation to anatomical oral structure. For this purpose 506 orthopantomagraph film, male 283cases and female 223 cases, aged from 15 to 30 years were evaluated by means of Winter's classification in conjunction with some other methods. Through the study following results were obtained; 1. The eruption of(equation omitted) were found in 229 cases followed by 61 cases of(equation omitted) and 45 cases showed no evidence of eruption. 2. The classification based on the relation of ramus to distal portion of the 2nd molar revealed class Ⅱ, 460 cases (61.8%) and 182 cases (24.5%) were class Ⅲ. 3. Parallelism between long axis of mandibular third molar and the second molar were found in 302 cases (40.8%) and mesial inclination of the third molar were 280 cases (37.6%). 4. Average inclination degree among these cases showed 138.62±12.56°.

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