The factors predisposing to the development of complications at various stages of the treatment of the patients presenting with odontogenic local perforative maxillary sinusitis include not only the specific anatomical features of the maxillary region but also the errors of planning and performing selected surgical and conservative interventions. Aim. The objective of the present study was to improve the quality of the combined treatment of the patients presenting with chronic odontogenic local perforative maxillary sinusitis by developing the new approaches to the prevention of complications of this pathology with the use of up-to-date means and technologies. Material and methods. A total of 68 patients presenting with perforations of the maxillary sinus floor were available for the observation. They included 12 patients with acute perforations of the maxillary sinus in the absence of the clinical symptoms of the chronic inflammatory process, 11 patients with odontogenic oroantral fistulas in the absence of the clinical symptoms of chronic maxillary sinusitis, 19 patients with chronic odontogenic local perforative maxillary sinusitis at the stage of exacerbation of the inflammatory process, and 22 patients presenting with chronic odontogenic local perforative maxillary sinusitis in the absence of exacerbation. The routine methods of clinical examination were supplemented by modern and diagnostically significant radiodiagnostic, microbiological, and functional studies. Results. The analysis of the results obtained in this study provided a basis for the formulation of the principal directions of prophylaxis of complications the probability of which is especially high at the stages of the surgical and postoperative treatment. These directions include the restoration of the lost bone tissues and the improvement of maxillary sinus drainage as well as the adequate antibacterial treatment.