How can tooth eat acerbity to do

summary

Tooth hypersensitivity is also called hypersensitive dentine or dentine hypersensitivity Hypersensitivity is a kind of pain symptom caused by external stimulation, such as temperature (cold, heat), chemical substances (acid, sweet) and mechanical action (friction or biting hard objects). It is characterized by rapid onset, sharp pain and short time. Dental hypersensitivity is not an independent disease, but a common symptom of various dental diseases

How can tooth eat acerbity to do

1. According to neurology, there are pulp nerve endings in dentin, so sensation can be transferred from the surface of dentin to pulp. However, there is no consensus on the morphology and function. Many scholars believe that only a part of the unmyelinated nerve in the odontoblast layer of dental pulp enters into the inner layer of prophase dentin and dentin, and no nerve structure is found in the outer 2 / 3 of the unmyelinated nerve. Many experimental results also do not support the view that "nerve response to various stimuli is direct". The effect of potassium chloride, histamine and acetylcholine on the superficial dentin did not produce pain, and the effect of local anesthetics on the surface of dentin could not reduce the sensitivity of dentin.

2. According to the theory of dentin fiber conduction, the protoplasm of odontoblast contains acetylcholinesterase, which can cause nerve conduction and pain after stimulation. The opponents hold that experimental interference with human odontoblasts does not reduce dentin sensitivity, indicating that odontoblasts do not have the characteristics of sensilla and may only play a passive role in dentin hypersensitivity.

3. According to the theory of fluid dynamics, the pain caused by air, hypertonic solution or temperature stimulation is caused by the movement of the liquid in the dentin tubules, which mechanically agitates the pulp contents, and indirectly excites the free nerve endings, and then transmits impulses to produce pain. The energy associated with the movement of the fluid can be converted from the pulp receptors into electrical signals. About 25% of the dentin volume is occupied by free fluid. Its composition and properties are similar to other body fluids and communicate with pulp tissue fluid. Dentin tubules are capillaries with a diameter of 0.8-2.5 μ M. therefore, the effect of fluid dynamics depends on the permeability of dentin tubules or the condition of dentin surface. There are air drying, hypertonic solution and cold stimulation that cause dentin fluid to move outward. The stimulation that makes dentin fluid move inward includes mechanical stimulation or heating. Dentin is very sensitive in the early stage of dentin exposure, and the natural relief of dentin sensitivity is the result of mineral deposition in dentin tubules or dental pulp forming restorative dentin.

matters needing attention

Among the pathogenesis of tooth hypersensitivity, the theory of fluid dynamics is widely accepted. According to this theory, the effective treatment of hypersensitivity is to close the dentin tubules to reduce or avoid the fluid flow in dentin. Because of the spontaneous desensitization process, it is extremely difficult to evaluate the efficacy of any drug.