Evaluation and comparison of floozies and DMFT and their relation with the amount of fluoride in three flowing source of drinking water (Karoon, Maroon, Karkheh) in 12-15 years old students in Khozestan 2002

Fluorine is the most important chemical element that changes the tooth surfaces, therefore it's consumption within the permitted range is useful for dental health, but it's decrement or increment over the optimal range causes damages to different body and dental systems. The amount of flouride in surface water has been stated to be about 0.5 mg.l which is less than the optimal level of flouride in drinking water suggested by WHO (1 ppm). According to study of the ministry of health and medical education in 1998, more than 68% of drinking water in Khoozestan province is provided from surface water resources and fluorosis and dental caries are seen abundantly in the province. In order to determine the role of fluoride this study has been made to evaluate the prevalence rate of fluorosis and DMFT and also compare them in Maroon, Karoon and Karkheh branches. The purpose of this study was to determine the prevalence of hypodontia in 15 year old students (boys & girls) in AHWAZ on 2002. Method & Materials: During this analytical descriptive study, 1152 twelve to fifteen years old students were examined regarding different fluorosis rates (Dean index) and DMFT rate (WHO index). Each student had a questionnaire including demographic in formation, oral hygiene status, caries and fluorosis. Collected data was analysed using T, chi – square test and Spearman – Pearson tests. Prevalence of fluorosis in Maroon, Karoon and Karkheh branches was 62.2%, 34.9% and 57.3% respectively and the average of DMFT was 1.33, 1.20 and 0.6. Increase in fluoride level caused increase in fluorosis prevalence (P<0.001). Fluoride increment in drinking water and prevalence of fluorosis have been accompanied by DMFT decrement in Karoon and Karkheh branches, but in Maroon branch, with fluoride increment of drinking water and prevalence of fluorosis DMFT also increased. The evaluation of different Dean index rates show that: the caries free rate has decreased from degree 2 to degree 5. In Khoozestan province, in spite of low level of fluoride, lower than the level suggested by WHO the tropical climate, high level of sea foods consumption and possibly the high interest of people of this region to drink tea have caused high level of fluorosis. Beside the mentioned factors, the effect of economic and cultural verity in this province is seen from the result of this study.