In the majority of Teeth Whitening gels, potassium nitrate, fluorine and ACP are added to prevent sensitivity or use it when sensitivity occurs. However, the studies often show that these substances do not provide effective protection against sensitivity at the required speed and duration. For this reason, in the majority of the products in the market, more than 50% of the patients experienced sensitivity problems.
As a result of such a high rate of sensitivity incidences, sensitivity is accepted as a natural result of tooth whitening and is described as if it were a normal side effect.
Why do whitening gels tend to cause sensitivity?
Studies on this subject shows that in general, as a result of acidic hydrogen peroxide and acidic liquid contact there occurs different types of sensitivities. In addition, it is stated that dehydration of teeth due to gels containing high hydrogen peroxide increases this effect.
The “oxygenation” reaction created by the whitening gel causes the loss of matter by decomposing the smear layer.
The smear layer also acts as a seal. The hydraulic conductivity of the fluids in the dentin tubules increases when this layer begins to decompose by oxygen. It may come in contact with the whitening gel, resulting in a strong osmotic shrinkage fluid in the dentin tubules. As a result, a growing intensity of sensitivity begin. This is a type of sensitivity that is the result of osmotic withdrawal.
In addition to this, the acidic structure in hydrogen peroxide whitening gels can also lead to increased fluid flow and increased sensitivity. Low-water and acid-dense gels have a stronger osmolality, leading to more osmotic shrinkage on the dentin tubular fluid. Strong fluid flow in the dentin tubules and acute pulpal whitening may create sensitivity.
During and / or shortly after whitening, the patient may feel a sharp, intense “lightning flash” effect. Patients generally describe this pain as electric shock.