Exposed dentin and dentinal tubules

Exposed dentin and dentinal tubules represent a critical therapeutic target in the management of dentin hypersensitivity, a condition characterized by sharp pain in response to external stimuli. Dentin is a calcified tissue that forms the bulk of the tooth, containing thousands of microscopic fluid-filled channels called dentinal tubules that extend from the dental pulp to the enamel or cementum boundary (StatPearls, 2023). When protective layers are lost due to gingival recession or enamel erosion, these tubules become exposed to the oral environment. According to the hydrodynamic theory, stimuli such as cold, air, or osmotic changes cause rapid fluid movement within these tubules, which subsequently activates mechanoreceptors in the pulp to signal pain (Journal of Conservative Dentistry, 2014). Therapeutic agents target this system by either physically occluding the tubule openings to prevent fluid flow or by chemically desensitizing the intradental nerves to reduce their excitability (PubMed, 2013). Understanding the structural integrity and permeability of these tubules is essential for developing effective desensitizing treatments and restorative dental materials.

Other names

Dentinal tubulesExposed dentinDentin-pulp complexExposed dentinal surface

Desensitizing agents work through two primary mechanisms: physical occlusion of the dentinal tubules to prevent fluid movement (hydrodynamic theory) and nerve desensitization by increasing extracellular potassium ion concentration to block nerve impulse transmission.