Studies on the Innervation of Dental Pulp

The dental pulp is innervated by nociceptive afferents. Information on the axons innervating dental pulp and their morphological change during their intrapulpal course, glutamate signaling associated with pulpal axons and on the sensory receptors and ion channel expressed in the pulpal axons help understand pathologic dental pain and dentin sensitivity. Two different types of axons innervate dental pulp;Myelinated and unmyelinated axons. Myelinated axons undergo morphological change during their extrapulpal course from trigeminal ganglion to teeth. Morphological change of the myelinated axons allows embedding of receptors and ion channels into axonal plasmamembrane and become functional. Myelinated and unmyelinated axons show different pattern in distribution of their varicosities within the dental pulp, which may be associated with regional difference in glutamate signaling between myelinated and unmyelinated axons.