[The effects of local anesthesia on the thermoregulation of the tooth pulp]

Laser Doppler flowmetry was used to measure the effects of local anesthesia on the thermoregulation of the tooth pulp. Heat affecting the pulp is physiologically offset by a reactive increase in blood flow. An increase in temperature from 35 degrees C to 45 degrees C results in an increase in blood flow by 100%, on an average. Local anesthetics produce a reversible block of this protective mechanism, thus eliminating more or less the reactive increase in blood flow. Under local anesthesia the defence power of the tooth pulp against noxious temperatures seems to be considerably reduced.