Dentinal tubules and dentin mineral matrix

Dentinal tubules and the dentin mineral matrix constitute the primary structural component of the human tooth, situated between the enamel and the dental pulp. The dentin mineral matrix is a calcified tissue consisting of approximately 70% inorganic hydroxyapatite, 20% organic collagen fibers, and 10% water (StatPearls: Physiology, Dentin, 2023). Traversing this matrix are the dentinal tubules, microscopic channels that house odontoblastic processes and dentinal fluid, serving as a conduit for sensory stimuli from the external environment to the pulp (PubMed: PMC3894084). This complex is a critical therapeutic target for managing dentin hypersensitivity and dental caries. Treatments focus on either occluding the tubules to stop fluid flow—based on the hydrodynamic theory of pain—or remineralizing the matrix to arrest the progression of decay (Journal of Conservative Dentistry, 2014). Understanding the physical and chemical properties of this target is vital for the development of restorative materials and desensitizing agents in clinical dentistry.

Other names

DentinDentinal canaliculiDental mineralized matrixDentin-pulp complex

Therapeutic agents target this structure through two primary pathways: physical occlusion and chemical desensitization. Occluding agents like stannous fluoride, arginine-calcium carbonate, and calcium sodium phosphosilicate (NovaMin) form precipitates that block the dentinal tubules, preventing the hydrodynamic movement of fluid that stimulates pulpal nerves (Journal of Clinical and Experimental Dentistry, 2021). Alternatively, potassium-based salts (e.g., potassium nitrate) increase the extracellular potassium concentration around nerve fibers within the tubules, depolarizing the membranes and inhibiting the transmission of pain signals (StatPearls: Physiology, Dentin, 2023). Remineralizing agents also interact with the dentin mineral matrix to promote the growth of hydroxyapatite crystals, restoring the structural integrity of the tissue (PubMed: PMC4252862).