Insufficient supply of iodine in regions with a natural deficiency of the microelement adversely affects the function of the thyroid gland and the state of the dental system in the child population. The aim of this study was to assess the state of the dental status and oral hygiene of the child population living in the territory with biogeochemical iodine deficiency. Our study included 289 schoolchildren aged 12 and 15 years old from three regions of Bashkortostan (Russia) located in the mountains and foothills of the Southern Urals. The following parameters were assessed: concentration of iodine in the urine, content of thyroid-stimulating hormone and free thyroxine in the blood plasma, the state of the mucous membrane and soft tissues of the oral cavity, prevalence of dentoalveolar anomalies, indexes of the CFE/cf and ACI, PAM and SHI. It has been shown that children and adolescents have a high prevalence of iodine deficiency, accompanied by an increase in the level of thyrotropin in the blood plasma and a decrease in free thyroxine. The schoolchildren of both ages with insufficient iodine supply have a significantly higher frequency of occlusal anomalies, occlusal deformities, anomalies of the dentition and individual teeth; non-carious and carious lesions of the teeth, and periodontal pathology. The children and adolescents with iodine deficiency have worse indices of CFE/cf and ACI, PAM and SHI, and oral hygiene status. The necessity of developing a complex of therapeutic and preventive measures of dental care, combined with an adequate supply of iodine, is stated.