A STUDY OF TOOTH NUMBER ANOMALY USING PANORAMIC RADIOGRAPHS

파노라마 X선사진을 이용한 치아수 이상에 관한 연구

The purpose of this study was to evaluate the prevalence and distribution of tooth number anomaly by means of the analysis of panoramic radiographs in 6,531 patients visited the Dental Infirmary of Kyungpook National University Hospital from January 1983 to May 1992. The results were as follows: 1. The prevalence of congenitally missing teeth except third molar was revealed to be 10.8%, and there was a hihger prevalence in females(44.6%) than in males(55.4%). Mandibular 2nd premolars(23.2 %) were absent most frequently, followed by maxillary lateral incisors(18.4 %), mandibular lateral incisors(18.3%), and maxillary second premolars(15.4 %) in descending order of frequency. As to the number of congenitally missing teeth, the percentage of missing one tooth was 48%, missing two teeth was 35.4 %, missing three teeth was 6.6%. 2. he prevalence of congenitally missing third molars was revealed to be 39.7%. There was a higher prevalence n the maxilla(60.3%) than in the mandible(39.7%). Maxillary right 3rd molars(30.6%) were absent most frequently, followed by maxillary left 3rd molar(29.7%), mandibular right 3rd molar(202%), mandibular left 3rd molar(19.5%) in descending order of frequency. 3. The prevalence of supernumerary teeth was revealed to be 4.2%, and there was a higher prevalence in males(65.7%) than in females(34.3 ). They were ound most frequently in maxillary central incisor area(64.8%), followed by maxillary lateral incisor area(132%), posterior area of maxillary third molar(8.7%) in descending order of frequency. As to the number of supernumerary teeth; The percentage of one supernumerary tooth was 79.9%, two supernumerary teeth was 8.9%, three supernumerary teeth was 1.2 %.

경북대학병원 치과에 내원한 8세에서 27세까지의 환자 6,531명의 파노라마 X선사진에서 제3 대구치를 제외한 선천성 결손치, 제3대구치의 선천성 결손, 과잉치의 발생율, 성별분포, 호발 부위 및 수에 따른 분포를 조사하여 다음의 결과를 얻었다. 1. 제3대구치를 제외한 선천성 결손치의 발생율은 10.8%였으며, 남성이 44.6%, 여성이 55.4%였다. 하악 제2소구치가 23.2 %로 가장 많았으며, 상악 측절치 18.4%, 하악 측절치 18.3%, 상악 제2소구치 15.4%의 순으로 나타났다. 결손치의 수는 1개 인 경우가 48%로 가장 많았으며, 2개인 경우가 35.4%, 3개인 경우가 6.6%로 나타났다. 2. 제3대구치 선천성 결손의 발생율은 39.7%였으며, 남성이 48.6%, 여성이 51.4%였고, 상악 60.3%, 하악이 39.7%였다. 결손치의 수는 1개인 경우가 28.7%, 2개인 경우가 37.2%, 3개인 경우가 12.5%, 4개인 경우가 21.6%로 나타났다. 3. 과잉치의 발생율은 4.2%였으며, 남성이 65.7%, 여성이 34.3%였다. 상악 중절치부가 64.8%로 가장 많았으며, 상악 측절치부 13.2%, 상악 제3대구치 후방부 8.7%의 순으로 나타났다. 과잉치의 수는 1개인 경우가 79.9%로 가장 많았고, 2개인 경우가 18.9%, 3개인 경우가 1.2%로 나타났다.