EFFECTS OF COOLING AND HEATING OF THE TOOTH ON PULPAL BLOOD-FLOW IN MAN

Laser Doppler flowmetry (LDF) was used to study the changes in pulpal blood flow (PBF) evoked by application of cold or heat to the palatina l surfaces of teeth 11 or 21 in nine young subjects. Switching from a thermode temperature of 33-degrees-C to 5-degrees-C on average induced a slow decrease of PBF to about 80% of control, and also warming to 3 9-degrees-C evoked a small reduction in most subjects. Interindividual differences were large, however, and both cooling and warming sometim es triggered a rise in PBF. In contrast, skin blood flow, as recorded with LDF in the forearm, invariably rose during warming and fell durin g local cooling. The results suggested a more complex interaction betw een local and nervously mediated effects of moderate changes in temper ature in the tooth pulp than skin, and that the previously held view o f cold and heat decreasing and increasing PBF, respectively, is wrong.