Objectives: Dental caries is a public health problem that affects pre-school and school children throughout the world. Poor oral health profoundly affects a person’s quality of life. Information on caries prevalence and severity represents the basis for caries prevention programs and indicates treatment necessity in the population. The occurrence of permanent teeth caries particularly in non-industrial societies, seems to be highThe aim of this study was to present the prevalence of dental caries inunder supervision 12 years old children living in Tehran and to assess the influence of the factors which are related to their oral health.

Methods: This cross-sectional study was carried out on 113 undersupervision children.The clinical examinations focused on dental status, expressed as DMFT (Decayed, Missed, Filled Permanent Teeth) index,following WHO standards methodologies. Clinical examinations and personal interviews to investigate the related factors to oral health were conducted by a single investigator.

Results: The level of DMFT was estimated at 1.32±0.86. Among the relevant factors, the reason for visiting the dentist (P<0.0001) and duration of stay in the center (P<0.04) had a meaningful relation to DMFT index of more than 2.

Discussion: The community under the research has a good condition as compared with the WHO goal. Further studies are recommended due to meaningful relation between DMFT index and the reason for visiting dentists as well as the duration of stay in the center.