Abstract
An investigation was performed on 721 patients who received treatment at the Orthodontic Department of Kyushu Dental College during a 5 year period from 1977 to 1981, concerning distribution of sex, age, and time of first treatment, kinds of malocclusion, orthodontic appliance used for active treatment, etc., on the bases of the gnathostatic models, x-ray cephalograms and clinical records which were obtained from these patients. The results were as follows : 1) Out of the 721 total number of the patients, male numbered 243 (33.7%), and female 478 (66.3%). In other words, female accounted for two thirds of the total. 2) Analyzed by the kinds of malocclusion, the number of mandibular protrusion cases was the largest among the total number of the patients, that of crowding cases came next and that of maxillary protrusion cases came third, that of cleft lip, jaw and/or palate cases came fourth. 3) In the frequency of using different kinds of orthodontic appliances for treatment, the use of multi-banded appliances ranked top, that of lingual arch appliances ranked second, that of chin caps ranked third and that of head gear appliances ranked fourth. There was observed remarkable decrease in the use of activator and plate appliances during a five year period since 1977.
