On the basis of observations in 90 patients with odontogenic maxillary sinusitis who had been re-examined clinically and radiologically, the authors deal with the optimal utilization of all possibilities of conservative treatment. 74% of the patients were symptom-free, 55% presented a radiologically well pneumatized sinus. The healing quality of inflammatory alterations of the sinusal mucosa is once again confirmed by the observation of the course of the disease.