Does one sip of cold water ever make your teeth suddenly hurt? That’s tooth sensitivity — and it’s one of the most common things patients ask me about.
The good news is that sensitivity is often manageable. The important part is understanding why it is happening in the first place.
Sensitivity is a symptom rather than a diagnosis, so the most important step is understanding why the dentine has become exposed.
Why do teeth become sensitive?
Beneath the protective enamel of your tooth is a softer layer called dentine. Dentine contains thousands of microscopic channels called dentinal tubules, which lead towards the nerve inside the tooth.
Normally, these tubules are protected by enamel or gum tissue. But when dentine becomes exposed, things like cold drinks, hot foods, sweets or even cold air can cause movement inside these tiny tubules and stimulate the nerve.
That is what causes the classic short, sharp pain of sensitivity.
What can cause it?
There are several common causes.
Gum recession can expose the root surface of the tooth, where there is no protective enamel. Acidic foods and drinks can gradually soften and wear away enamel.
Brushing too hard or using a highly abrasive toothpaste can contribute to wear and recession over time. Poor oral hygiene can lead to gum inflammation and gum disease, which may expose more of the root surface and contribute to sensitivity.
Grinding or clenching can also contribute to tooth wear, cracks and sensitivity.
Can your diet make it worse?
Yes — especially if your teeth are exposed to acid frequently throughout the day. It’s not just about how much acidic food or drink you have, but how often.
Slowly sipping fizzy drinks, lemon water or fruit juice throughout the day gives your teeth repeated acid attacks. Try to keep acidic foods and drinks to mealtimes where possible.
Avoid brushing straight after acidic foods or drinks — rinse with water and give your saliva time to neutralise the acids first.
Which ingredients actually help?
Sensitivity products work in different ways.
Ingredients that help calm the nerve
Potassium nitrate — helps reduce the nerve response inside the tooth over time.
Ingredients that help block the open tubules
Stannous fluoride — helps protect against decay while also forming a protective layer over exposed dentine and blocking the tubules.
Arginine — helps form a mineral-rich protective seal inside open tubules, reducing sensitivity triggers.
Ingredients that help remineralise and protect the surface
Hydroxyapatite — a mineral similar to the one naturally found in teeth. It can help remineralise the surface and physically fill exposed dentinal tubules.
NovaMin — found in some Sensodyne sensitivity toothpastes. It reacts with saliva to release calcium and phosphate, creating a protective mineral layer over exposed dentine and helping block the tubules.
RECALDENT — found in products such as Tooth Mousse. It delivers calcium and phosphate to the tooth surface, helping remineralise and protect exposed dentine. Avoid it if you have a milk-protein allergy.
Whichever product you choose, the key is consistency. Sensitivity products work best when you use them regularly, not just when the sensitivity flares up.
What can you do at home?
Use an electric toothbrush with a pressure sensor. This helps you brush effectively while alerting you if you are pressing too hard.
Choose a toothpaste specifically designed for sensitivity and use it twice a day. You can also place a small amount directly onto the sensitive area after brushing and leave it there.
Good oral hygiene matters too. Keeping plaque levels low helps reduce gum inflammation and protects the gum line, which can help reduce sensitivity over time.
Try to reduce frequent acidic foods and drinks. And after brushing: Spit, but don’t rinse.
This leaves the active ingredients around your teeth for longer. If you use mouthwash, use it at a different time of day rather than immediately after brushing.
How do we treat sensitivity professionally?
The first step is always to find the cause. Sometimes changing your toothpaste, brushing technique, oral hygiene and diet is enough.
If the sensitivity continues, we may use professional fluoride varnishes, hydroxyapatite varnishes or other desensitising treatments to protect the exposed surface and reduce sensitivity.
In some cases, we may need to cover the exposed area with a small amount of composite material.
It is also important to make sure the pain really is sensitivity. Decay, a cracked tooth, a leaking filling, gum disease or inflammation of the nerve can feel similar and need the underlying problem treated.
When should you get it checked?
A quick, short response to cold can be simple sensitivity.
See your dentist if the pain comes from one particular tooth, lingers after hot or cold, starts without a trigger, hurts when you bite or is getting worse. These can be signs that something else is going on.
The most important thing to remember
Sensitive teeth are common, but there is usually a reason for it.
The key is to find the cause, protect the exposed surface and treat the underlying problem.
