The science behind how teeth can become sensitive with professional teeth whitening

Teeth sensitivity following professional whitening is a common side effect, and it occurs due to several factors related to the whitening process and the structure of the teeth. Here's the science and reasoning behind this sensitivity:

1. Penetration of Whitening Agents:

- Professional whitening treatments typically use strong bleaching agents, such as hydrogen peroxide. These agents penetrate the enamel to reach the dentin, the layer beneath the enamel, which contains microscopic tubules leading to the dental pulp (the innermost part of the tooth where nerves and blood vessels reside).

- The bleaching agents can temporarily enlarge these tubules or remove the plug-like material that seals them, exposing the nerves to external stimuli.

2. Exposure of Dentinal Tubules:

- During the whitening process, the protective layer of protein that covers the tubules in the dentin can be disturbed or removed. This exposes the nerves within the tubules to external changes, such as temperature, leading to sensitivity.

3. Dehydration of the Tooth:

- The whitening process can cause temporary dehydration of the tooth, making it more prone to sensitivity. When the teeth are dehydrated, the dentin contracts slightly, which can pull on the nerves within the tooth and cause discomfort.

4. Inflammatory Response:

- The whitening agents can induce a mild inflammatory response in the dental pulp, which increases pressure inside the tooth, contributing to sensitivity.

5. Pre-existing Dental Conditions:

- Individuals with pre-existing dental conditions such as gum recession, enamel erosion, or existing tooth sensitivity may experience more pronounced sensitivity after whitening treatments.

6. Concentration and Duration of Treatment:

- The concentration of the bleaching agent and the duration of its application can impact the degree of sensitivity. Higher concentrations and longer application times generally increase the likelihood of sensitivity.

The sensitivity experienced after teeth whitening is usually temporary and should subside within a few days after the treatment. To mitigate sensitivity, dentists may recommend:

- Using toothpaste designed for sensitive teeth before and after the whitening treatment.

- Limiting exposure to very hot or cold foods and beverages immediately following the treatment.

- Using fluoride treatments or desensitising agents to help remineralise the teeth and reduce sensitivity.

It's important for anyone considering professional whitening to discuss their concerns and dental history with a dentist, as they can provide tailored advice and help minimise discomfort.