Tooth mineral and dentinal tubules

Tooth mineral, primarily composed of hydroxyapatite [Ca10(PO4)6(OH)2], and dentinal tubules are the fundamental structural targets in the management of dental caries and dentin hypersensitivity (NIH, 2023). Dentinal tubules are microscopic, fluid-filled channels that extend from the dental pulp to the dentino-enamel junction, serving as a pathway for sensory stimuli (StatPearls, 2023). According to the hydrodynamic theory, external stimuli cause fluid movement within these tubules, which activates nociceptors in the pulp, resulting in sharp pain (PubMed, 2021). Pharmacological and therapeutic interventions target these structures to either restore mineral density or block sensory transmission. Remineralizing agents, such as various fluoride compounds, promote the formation of fluorapatite to strengthen the tooth mineral matrix and occlude tubule openings (Journal of Dentistry, 2020). Desensitizing agents like potassium nitrate work by increasing the extracellular potassium concentration around nerve fibers within the tubules, thereby inhibiting repolarization and reducing nerve excitability (Cochrane Database, 2014). Other treatments, including bioactive glasses and arginine-calcium carbonate complexes, physically plug the tubules to prevent fluid flow and provide rapid relief from hypersensitivity.

Other names

Dentinal tubulesHydroxyapatiteDental mineralTooth enamel mineralDentinal canaliculiDentin-pulp complex

Therapeutic agents target these structures through three primary mechanisms: tubule occlusion, nerve desensitization, and remineralization. Occluding agents (e.g., fluorides, oxalates, and arginine-calcium carbonate complexes) form mineral precipitates that physically block the orifices of dentinal tubules, preventing the hydrodynamic movement of fluid that triggers pain. Desensitizing agents, specifically potassium salts, penetrate the tubules to increase extracellular potassium concentration around pulpal nerve fibers, thereby inhibiting repolarization and reducing nerve excitability. Remineralizing agents promote the deposition of hydroxyapatite or fluorapatite onto the existing tooth mineral matrix to restore structural integrity and reduce permeability.