Epidemiologic studies have shown that caris or "infective damage of hard tissues in teeth" are the most common type of infection in human. In Iran, a few studies have investigated this hygienic problem, but no practical results have been defined yet. In this research, the conditions of the first upper and lower permanent molars (it contains four minor variables), have investigated. For this reason, in a descriptive analytic study, which was of retrospective and cross- sectional type, one thousand files were chosen systematically. The data were analysed by SPSS packages. The mean values of DMFT for permanent first molars were 3.47±0.50 (MT-1.23, FT=0.86, DT-1.38). The number of extracted teeth in mandible was moer than maxilla and the number of untreated caries teeth in maxilla was more than mandible (PO.001). DMFT ratio of the first molars to total DMFT, was approximately 29%, which indicates that caries and that complications on the first molars, make the main part of the overall DMFT. Therefore, hygiene training, preventive methods and the improvement of ecomonical status seem necessary in dental services.