بررسی شیوع ناهنجاری‌های دندانی-صورتی و نیاز به درمان‌های ارتودنسی در جمعیت دانش‌آموزی سال اول راهنمایی شهرستان کرج

Background & Objectives: Malocclusion is not a disease but rather a set of dental deviations, which in some cases can influence quality of life. The aim of this study was to assess the frequency of various dento–facial anomalies. Methods: In this cross-sectional study in 2006 we assessed a sample of 600 randomly selected schoolchildren, with a mean age of 11.97 years, who were attending secondary school in various districts of Karaj. We used questionnaires to obtain information on extracted teeth, crowding, spacing, diastem, the severest disorders in anteriors (maxilla and mandible), overjet, negative overjet, open space between two jaws and antero-posterior molar relationship.Results: Ninety-nine percent of children had no extracted teeth in maxillary anteriors, while 98.3% had no extracted teeth in mandibular anteriors. In 41.2% of the subjects there was no crowding, and 57.7% of the sample had no spacing. The mean diastem was 0.36 mm and the mean of the most severe disorders in anteriors was 1.08 mm in the maxilla and 0.78 mm in the mandible. Mean overjet was 1.98 mm, mean negative overjet 0.03 mm, and mean open space between two jaws was 0.28 mm. In 58.5% of the subjects the antero–posterior molar relationship was normal. The DIA ranged form 13 to 63, with a mean of 24.12.Conclusions: This study indicates that over than one-third of the population needs different degrees of orthodontic treatment.