It is very important to study the problem of caries and gingivitis in adolescents who are being treated for orthodontic pathology with bracket systems. The method of combined treatment which incorporates the use of medicine and laser therapy has been proved effective in caries prevention. This research aims to study clinical aspects of the effectiveness of the combined influence of the low-intensity laser "OPTODAN" with a wavelength of 0.85 μm (Scientific Development and Production Center "VEND", Saratov, Russia) in carries prevention. The research also aims to study the disinfection method of PAD with "FotoSan" ("CMS Dental", Denmark, with a wavelength of 625–635 nm, where toluidine blue is used as photosensitizer molecules) combined with regular measure to prevent gingivitis in adolescents being treated for orthodontic pathology with bracket systems. This paper presents the results of 1.5 years of clinical study of 60 12–13-year-old children. They were examined before and after the orthodontic treatment: their decayed, missing, filled teeth (DMFT), decayed, missing, filled tooth surfaces (DMFS) index and hygiene status (OHI-S) were calculated, gum inflammations were detected. Before the orthodontic treatment, their mouths were sanitized. After orthodontic appliances were placed, the children were randomly divided into two groups of 30 each. Children of the first group, while being treated with braces, took traditional preventative measures against gum inflammation and caries: occupational hygiene, local antiseptics (0.05% chlorhexidine solution), the use of remineralizing and phosphorus containing applications four times a year. The children of the second group, along with the traditional scheme of preventive measures, were treated with the devices "FotoSan" and "Optodan". Results of clinical examination of the second group have accurately proved decrease in the growth of dental caries intensity and surface caries intensity (△DMFT, △DMFS) and in gingivitis level at the end of the orthodontic treatment. So the results of our clinical research have proved the effectiveness of laser therapy and comprehensive prevention of caries and gingivitis in adolescents using bracket system.