The aim of this work was to determine the values of plaque accumulation indices and oral hygiene indices, to conduct a comparative assessment before the start of multimodality therapy in patients with mild and moderate parodontitis and after its completion among the adult population of the Chuvash Republic. The study of index evaluation values of 146 patients aged 33–62 years with a diagnosis "chronic generalized parodontitis of mild and moderate severity" was conducted. The age range was determined by the criteria for dividing the age groups according to WHO data – early adult (25–35 years), middle adult (36–45 years), late adult (46-60 years). The examination was carried out according to standard clinical methods of simplified oral hygiene index OHI-s (according to Green – Vermillion), dental plaque hygiene index (PI) Silness-Loe (1964), evaluation of the state of periodontal tissues PI (by Russel). The authors present the criteria for evaluating the indices before the start of standard treatment and after its completion for all the studied patients and in groups with mild and moderate severity of chronic generalized parodontitis. The authors give as well a comparative analysis of the patients’ index assessment depending on the severity of the disease, the dynamics of the infection resolution in groups with different degrees of of parodontitis severity.