A study on the distributions and trends in malocclusion patients from department of orthodontics, college of dentistry, Yonsei university

Yu, Hyng Seon; Ryu, Young Kyu; Lee, Jang Yeol

Abstract

Distributions trends were examined in 9159 malocclusion patients had been examined and diagnosed at Department of Orthodontics, College of Dentistry, Yonsei University over a 6 year-period from 1992 to 1997. The results were as follows: 1. The total number of orthodontic patients in 1997 increased in comparing with that of 1992(86%)and after 1995, the number of annual patients showed an increase. 2. Age distribution had shown over-19 year-old group being the largest(39.9%) but percentages of pre-adolescent patients had been decreasing while that of adult patient had gradually increased. 3. Distributions in the types of malocclusion, the Angle's Classification had shown : 33. 3% for Class I, 28.6% for ClassII and the largest 38.1% for Class III. 4. Among Class I patients, crowding showed the largest(32.6%) and protrusion group had gradually increased to 33.9% in 1996. Otherwise openbite and groups tend to decrease, annually. 5. Geographic distribution showed a majority of patients from Seoul(above 70%). Among the patients from Seoul, group within the distance 3-6km from Yonsei dental hospital was the largest(32.3%) and group within 9km showed 69% of total patients.