Examined the temporal relationship between the application of heat and cold to teeth, the evoked sensory response, and temperature changes in the region of the pulpodentinal junction.
N= 16 teeth to be extracted for ortho treatment from 8 patients were used. Heat and Endo ice were applied and the time elapsed for a response was recorded. Teeth were extracted and a thermal probe was placed to measure temperature changes occurring at Pulpodentinal junction with the application of heat and ice.
1.Mean response time for ice was 1.5 seconds and 1.3 seconds for heat.
2.The mean time for a temperature change to occur at the pulpodentinal junction was 3.7 seconds.
3.Mean maximum temperature change at the pulpodentinal junction was 3.9 C for heat.
Sensory response to thermal stimulation occurs before there is a temperature change in the region of the pulpodentinal junction where the sensory nerve endings are located.