Peripheral sensory nerve fibers in dentin

Peripheral sensory nerve fibers in dentin are specialized neuronal extensions that originate from the dental pulp and penetrate the inner portion of the dentinal tubules. These fibers are primarily composed of myelinated A-delta fibers and unmyelinated C-fibers, which are responsible for transmitting pain signals in response to thermal, mechanical, or chemical stimuli (StatPearls, Dental Anatomy, Pulp and Pathology, 2023). According to the widely accepted hydrodynamic theory, fluid movement within the dentinal tubules triggers these mechanosensitive fibers, resulting in the sharp pain characteristic of dentin hypersensitivity (Journal of Clinical Periodontology, 2013). These nerve endings express a variety of molecular targets, including voltage-gated sodium channels (Nav1.7, Nav1.8) and transient receptor potential (TRP) channels such as TRPV1 and TRPA1, which are involved in nociceptive processing (PubMed, Journal of Endodontics, 2018). Pharmacological management of dental pain often involves local anesthetics like lidocaine to block sodium channel conductance or desensitizing agents like potassium nitrate that reduce nerve excitability by altering membrane potential (American Dental Association, 2022). While these fibers are essential for the tooth's sensory and protective functions, their over-activation is the primary driver of clinical dental distress.

Other names

Intradental nerve fibersDentinal sensory nervesPulpal nerve endingsNociceptive fibers of the dental pulpA-delta and C-fibers of the dentin-pulp complex

Drugs targeting these fibers typically function by inhibiting voltage-gated sodium channels to block action potential propagation, or by using potassium ions to depolarize the nerve membrane and induce a refractory state, thereby reducing excitability.