Tooth pain is the most common form of orofacial pain. Tooth sensory system is very sensitive to detect noxious stimulus. Most of sensory stimulus, which come from pulp afferent fibres will cause pain sensation. Action potential transmits the stimulus from periphery to the central. Sodium channels have an important role to generate and propagate the action potential. One of its isoforms, Nav1.8, has only found in sensory nerve, especially in nociceptive neuron that deliver pain stimulus. In myelinated neuron such as A-δ fibres, sodium channels located in high density on the node of Ranvier. The density of sodium channel Nav1.8 has a strong relation with tooth sensitivity. We implement method to detect nodes of Ranvier and detect Nav1.8 as our region of interest. In this paper, threshold and local enhancement is used for nodes of Ranvier detection and improvement of Euclidean path for sodium channels Nav1.8 detection.