Prevalence of Open Bite Malocclusion Among 11 - 12 Years Old School Children in Yazd, Iran

Background: many studies have been conducted in iran to know the prevalence of malocclusions and orthodontics needs but no study so far has been conducted in yazd.objectives: the aim of this study was to determine the prevalence of anterior open bite (aobo) among 11 - 12 years old school-aging children in yazd, iran.patients and methods: a total number 550 (278 boys and 272 girls) school aging children between 11 - 12 years old with permanent dentition were selected in this study from yazd, iran. the subjects were randomly selected, and none had received previous orthodontic treatment. clinical examinations were carried out by one trained and calibrated examiner. the occlusal anteriorposterior sagital relationship were assessed based on the angle classification and also the vertical anterior relationship. the statistical software spss version 22 was used for the analysis different parameters as gender and age.results: aob was present in 2.9% of subjects. 2.1% of the male and 3.6% of the females students in the sample were affected with anterior open bite. the prevalence of class i, class ii and class iii malocclusion with aob was 1.7%, 3.2%, 21.4%, respectively.conclusions: this study shows that 2.9% of children examined had anterior open bite malocclusion which required treatment.