The aim — to study the effect of toothbrushes of various types on the accumulation of plaque and the proteolytic potential of gingival fluid as a pathogenic factors in long-term orthodontic treatment of patients with a distal permanent bite. Material and methods. We examined 63 patients of both sexes aged 11—18 years. Orthodontic treatment was carried out for the close position of the teeth with a distal permanent bite (K07.2) and cleft palate and lips (Q37.1). Patients were divided into three groups depending on the type of toothbrush used for individual oral hygiene: group 1 (n=21) — an orthodontic manual toothbrush (Professor Persin, «Spazzolificio Piave», Italy); Group 2 (n=22) — an ultrasonic toothbrush (Emmi-dent, EMAG AG, Germany) and group 3 (n=20) — an electric toothbrush (“Oral-B Pro-Expert, «Procter & Gamble», USA). Results. The amount of soft plaque was assessed by the Silness-Loe hygiene index in the subgingival region. The activity of proteolytic enzymes — elastase, collagenase, and a α-inhibitor of proteinases was determined by the enzymatic method using a XL 200 biochemical analyzer («Erba Lachema», Czech Republic). The accumulation of plaque in the gingival region on both jaws during the entire period of orthodontic treatment is most pronounced when using a manual brush compared to ultrasonic and electric brushes. An increase in proteolytic activity in the gingival fluid with a simultaneous decrease in antiprotease potential with long-term orthodontic treatment of patients was observed when using a manual orthodontic brush, which can be regarded as an increase in the activity of the pathogenic factors for the development of local inflammatory and destructive changes. Conclusion. To prevent inflammatory and destructive changes during prolonged orthodontic treatment of patients, the use of ultrasonic and electric toothbrushes in daily oral hygiene is justified.