Association between season and temperature and unstimulated parotid and submandibular/sublingual secretion rates

Objective: The purpose of the present study was to evaluate parotid and submandibular/sublingual (SM/SL) unstimulated salivary secretion rate in a group of healthy individuals in winter and summer, and to observe the effect of room-adjusted temperature (air-conditioning) on salivary flow-rate in those seasons. Design: Unstimulated salivary secretion rates of the right parotid and the SM/SL glands were measured in 50 healthy Israeli volunteers. Each volunteer was evaluated four times during the study: twice in winter (February-March) and twice in summer (July-August). Results: Parotid and SM/SL salivary mean secretion rate in winter was significantly higher than in summer (p < 0.02 and p < 0.05, respectively). Room heating in winter lowered significantly the mean parotid flow. Air-conditioning cancelled almost completely the seasonal effects on parotid and SM/SL secretions. Conclusions: The results of this study suggest that room temperature is an important factor in measurement of salivary secretion rate. Hence, temperature should ideally be recorded and reported when assessing salivary flow-rates.