An increased frequency of odontogenous abcesses was observed on certain days in the course of routine clinical practice. We therefore investigated the possibility of a statistically significant weather-related odontogenous soft-tissue purulence originating from chronic apical periodontitis. Medical reports of patients treated between 1970 and 1977 were used. Our study indicated that the frequency of odontogenous abcesses was significantly higher with cyclonic weather conditions, i.e., weather with low barometric pressure.