The incidence of patients with chronic rhinosinusitis (CRS) has increased by 150—200% in recent years. According to some sources, chronic maxillary sinusitis (CMS), including odontogenic CRS, accounts for some 20—40% of the total number of inflammatory diseases of the maxillary sinus. One reason for the increased frequency of odontogenic rhinosinusitis is the wide use of dental implants to treat secondary edentulism. The goal is to develop methods to improve the efficacy of treatment for patients with CRS and secondary edentulism. Patients and methods. A total of 26 patients aged 27—65 years with cystic maxillary sinusitis and secondary edentulism of the posterior teeth in the upper jaw were examined. All of the patients were treated using surgical treatment for CMS with simultaneous maxillary sinus bone grafting, a technique developed by the authors. Conclusion. Cone beam computed tomography monitoring of the paranasal sinuses, 6 months and 1 year after surgery, resulted in no reported recurrences of cysts in the maxillary sinus. Postoperatively, there was increase in the quality of life (disability index was zero). The method presented here has helped, not only to reduce the rehabilitation period for this group of patients to 9 months, but also to avoid the recurrence of cysts in the maxillary sinus floor over the long term.