گياهان دارويي منطقه حفاظت شده گنو

Background and Aim: Enamel defect is a developmental disorder which may be occurred with other tissues dysplasia. Following any quantitative and qualitative defects of enamel and dentin, teeth susceptibility to decay is observed. Disorders of any type in enamel developmental process may lead to complications in the appearance and microscopic structure of enamel. The aim of this study was to determine the prevalence of enamel defects in permanent incisors and first molars and its influencing factors among (8-9) - year - old children of Tehran. Materials and Methods: In this nested case control study, 1400 primary school students from 5 educational regions (1-6-8-9-16) were randomly selected. In each region, two girl schools and two boy schools, out of each 140 grade two students were randomly selected as case and control groups. Subjects were examined clinically using a portable light, a mirror and probe. After dental examination, a questionnaire comprising of possible etiologic factors was filled by parents. The obtained data were analyzed through Chi - square and fisher exact tests. Results: The prevalence of enamel defects was 34.2% in girls and 30.1% in boys. Enamel defects were found as follows: 65 children with permanent incisors, 222 children with permanent first molars and 165 children with permanent first molars and incisors defects. A statistically significant correlation (P<0.05) was observed between enamel defects and respiratory diseases Conclusion: Although the etiology of enamel defects is not thoroughly recognized, it seems that embryonal and infantile disorders, especially respiratory diseases in the first 5 years of life, are important factors.