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Updated: Jun 3, 2026

Determining heat and mechanical pain threshold in inflamed skin of human subjects
Published on: January 14, 2009
Analysis of thermal-induced dentinal fluid flow and its implications in dental thermal pain
Min Lin1, ShaoBao Liu, Lin Niu
1Biomedical Engineering and Biomechanics Center, School of Aerospace, Xi'an Jiaotong University, Xi'an 710049, PR China.
Objectives:
The initiation of the pain sensation experienced following the thermal stimulation of dentine has been correlated with fluid flow in the dentinal tubules. There may be other mechanisms.
Methods:
This study examines this possibility using a mathematical model to simulate the temperature and thermal stress distribution in a tooth undergoing thermal stimulation. The results obtained were then used to predict the fluid flow in a single dentinal tubule by considering the deformation of the dentinal tubules and dentinal fluid.
Results:
Deformation of the pulp chamber was observed before a noticeable temperature change was recorded at the dentine-enamel junction. Tubule deformation leads to changes in fluid flow more rapidly than fluid expansion or contraction. This finding agreed with previously reported experimental observations. An initially high rate of outward fluid flow under cooling was found to correspond to short latency neural responses whilst heating was associated with long latency neural responses.
Conclusion:
Rapid fluid flow caused by thermal deformation of dentinal tubules may account for the short latency (<1s) activation of mechano-sensitive receptors after of cooling. Long latency (>10s) neural responses could be associated with the activation of thermo-sensitive receptors.
