بررسي شيوع كراس بايت خلفي در كودكان 3-5 ساله مهدكودكهاي شهر زاهدان در سال 1381

Prevalence of posterior crossbite in (3-5) years - old nursery schoolsʹ children in Zahedan in 2002 - 2003

Background and Aim: Posterior crossbite is a common phenomenon in primary dentition which is classified in three general types of skeletal, dental and functional which are not mostly self - corrected, however; a suitable and on - time treatment may prevent it to change into a skeletal disorder. The goal of this study was to determine the prevalence of posterior crossbite among 3-5 year-old nursery schoolʹs children in Zahedan. Materials and Methods: In this cross - sectional descriptive study, data were gathered through clinical examination and questionnaire in 870 children, 500 boys and 370 girls. The unilateral crossbite was characterized by cusp - to - cusp position of molars in central occlusion and the mandible, to find a stable occlusion, had to slide to one side. If there was no midline deviation it was classified as bilateral cross-bite. The data were analyzed using descriptive statistical methods and X2 test. Results: The prevalence of posterior crossbite in the studied group was 3.2%. The posterior cross-bite was more in girls (4.3%) than boys (2.4%). Unilateral posterior crossbite was observed in 92.8% of cases and bilateral posterior crossbite was seen in 7.2%. Conclusion: The prevalence of posterior crossbite was 3.2% in (3-5) year - old children in Zahedan nursery schools.