Journal of Dental Medicine

Background and Aim: Extensive studies on the epidemiology of teeth and oral diseases are an important part of health care programs specially for hearing impaired groups. For adequate programming in this field, proper situation analysis is mandatory. The aim of this study was to assess the DMFT (decayed missed filled teeth) of 12 years old students attending hearing impaired schools in Tehran and exploring the relation between sex, hygiene and hearing threshold with the index.

Materials and Methods: This cross sectional descriptive study was based on examining 12 years old (± 6 month) students (117 cases) attending hearing impaired schools in Tehran. A questionnaire was filled for each case. T, Chi-square and Kruskall-Wallis tests were used to analyze the results with p<0.05 as the limit of significance.

Results: The mean DMFT in these students was 3.07. Mean DMFT in students with very severe hearing loss was 2.99. Mean ranked DMFT in girls and boys was similar (56.09 in boys and 61.96 in girls). Mean ranked DMFT in students who didn’t use floss (66.40) was higher than those who used floss (46.71). Mean ranked DMFT in students who seldom brushed, was the highest (72.82) and in students who brushed once a day was the lowest (51.26).

Conclusion: The DMFT index in hearing disabled children was 3.07. Regular brushing and flossing reduced the index.

Background and Aims: One of the common human evolutionary anomalies is dental Missing. Evolution of dental system is toward deduction of teeth number. The Missing of third molar is interesting subject for dentists and genetic researches because of its variety in different races. Consideration of bilateral effect of third molar Missing with jaw relation is an important subject. The aim of this study was to evaluate the third molar missing in Cl I and Cl II skeletal (without rotation) and comparison of them together.

Materials and Methods: The patients of the orthodontic department of school of Dentistry (Tehran University of Medical Sciences) were analyzed. About 121 patients had Cl I and 60 patients had ClI jaw relation. This relation identified based on cephalometric lateral radiographic ANB corner angle. Patient who had rotation in maxilla or mandible based on SN-Go Gn angle were excluded. The incidence of third molars agenesis in individual dentition quadrants, upper and lower jaw and right and left side of dentition was examined from panoramic radiography. AChi-square test was used for statistical analysis of data.

Results: Missing of one or more third molar in skeletal Cl I and Cl II was 43% and 33.3%, respectively. Missing of one or more third molar in Cl II was fewer than Cl I, but no statistically significant differences were seen between them.

Conclusion: There was not a direct relationship between jaw relation and third molar Missing.