Sensitive teeth are almost always the result of exposed dentine — the layer beneath the enamel, threaded with microscopic tubules that lead towards the nerve. When those tubules are open to the mouth, cold, sweet and air cause fluid movement inside them, and the nerve registers it as a short sharp pain.
The key word is short. Sensitivity is sharp and stops as soon as the trigger is removed. Pain that lingers for minutes, or that arrives on its own, is something else — see toothache: what the pain is telling you.
How dentine becomes exposed
Gum recession
The most common cause. Root surface is not protected by enamel, so once the gum recedes it is directly exposed. Recession comes from brushing too hard, from gum disease, from grinding, and from ageing — see gum recession.
Acid erosion
Fizzy drinks, citrus, juice, wine, vinegar-based foods, and stomach acid from reflux all dissolve enamel. It thins evenly rather than in a hole, which is why erosion is often missed until teeth become sensitive and start to look shorter or more yellow.
Brushing too hard
Hard brushing with a hard brush, particularly with an abrasive paste, wears a notch at the gum line and pushes the gum back. It is one of the few causes where people are actively making it worse while trying to do the right thing.
Grinding and clenching
Wears through enamel on the biting surfaces and flexes the tooth at the gum line — see teeth grinding and jaw clenching.
After treatment
Temporary sensitivity is common after a filling, after a deep clean, and after whitening. It should be settling within days to a couple of weeks — see tooth sensitivity after whitening.
A cracked tooth or a failing filling
Usually affects one tooth rather than several, and often produces pain on biting as well.
What actually works
Desensitising toothpaste, used properly
Look for potassium nitrate or stannous fluoride. The important part is how it is used: brush with it twice a day, and then rub a small amount directly onto the sensitive area with a clean finger and leave it without rinsing, ideally last thing at night. Most people use it as ordinary toothpaste and rinse it straight off, which is why they conclude it does not work.
Give it two to four weeks before judging.
Stop rinsing after brushing
Spit, do not rinse. This keeps fluoride and active ingredients on the teeth and is the single easiest change to make.
Change how you brush
Soft brush, light pressure, small movements angled towards the gum line. If you have been scrubbing, this alone often produces improvement within weeks. Many electric brushes have a pressure sensor, which is genuinely useful here.
Address the acid
Reduce how often acidic things are consumed rather than only how much. Drink them with meals, finish them rather than sipping, and rinse with water afterwards. Do not brush for around thirty minutes after anything acidic — softened enamel brushes away.
If you have reflux, treating it matters dentally as well as medically.
Treatments at the clinic
- Fluoride varnish applied to the sensitive areas.
- Desensitising agents that seal the dentine tubules.
- Bonding over an exposed or notched area at the gum line.
- A night guard where grinding is the cause.
- Gum treatment where recession is due to periodontal disease — see gum and periodontal care.
- Treating the specific tooth where a crack, cavity or failing restoration is responsible.
When it is not simple sensitivity
See a dentist rather than reaching for another toothpaste if:
- The pain lingers for minutes after the cold is removed.
- It wakes you at night or arrives spontaneously.
- It is confined to one tooth, particularly with pain on biting.
- Heat triggers it more than cold.
- There is swelling, a bad taste, or a bump on the gum.
- It has not improved after a month of desensitising treatment.
Why it matters beyond comfort
People with sensitive teeth often avoid brushing the area that hurts. That allows plaque to accumulate exactly where the gum is already receding, which causes more recession and more sensitivity — and root surface decays more readily than enamel. Breaking that cycle is the practical reason to treat sensitivity rather than live with it.
Working out which cause is yours
The pattern of sensitivity is usually enough to point at the cause, and it determines the treatment.
Several teeth, at the gum line, worse on the side you brush hardest. Almost always brushing trauma and recession. The fix is technique, not a stronger product.
Generalised, with teeth looking shorter or more yellow, and edges becoming translucent. Acid erosion. Look at what you drink and how often, and consider reflux.
Worse in the morning, with jaw tightness or headaches. Grinding.
One tooth only, particularly with pain on biting. Not general sensitivity — a crack, a cavity or a failing restoration.
Started after a specific appointment. Expected after a filling, a deep clean or whitening, and should be settling within days to a couple of weeks.
Along the gum line with visible root surface and gums that bleed. Periodontal, and the recession is a symptom of something that needs treating.
The four-week plan
Before assuming you need treatment, run this properly. Most sensitivity from exposed dentine responds.
- Switch to a soft brush and use light pressure with small movements angled at the gum line. If your brush has a pressure sensor, pay attention to it.
- Use a desensitising toothpaste twice a day — and additionally rub a small amount directly onto the sensitive areas with a clean finger last thing at night, and leave it. Do not rinse.
- Stop rinsing after brushing at all. Spit only.
- Stop using abrasive or charcoal pastes.
- Change how you take acidic things: with meals, finished rather than sipped, rinsed with water afterwards, and no brushing for thirty minutes.
- Give it four weeks before judging.
If there is no improvement by then, it needs an examination rather than another product.
Why treating it matters beyond comfort
Sensitivity quietly changes behaviour. People brush the affected area less, avoid cold water there, and chew on the other side. The result is more plaque exactly where the gum is already receding — which causes more recession, more exposed root, and more sensitivity.
Exposed root surface also decays considerably faster than enamel and is harder to restore, because the margins sit at or below the gum. Breaking that cycle early is far easier than managing root decay later, particularly in anyone with a dry mouth.
Frequently asked questions
How long until desensitising toothpaste works?
Two to four weeks of consistent use, including rubbing it on and not rinsing. If there is no change by then, have it assessed.
Should I use a hard brush to clean better?
No. Hard brushes and hard pressure cause the problem. Soft brush, light touch, good technique.
Is whitening making it worse?
Whitening causes temporary sensitivity that should settle. If yours is not settling, it may be revealing an underlying problem.
Can sensitivity go away on its own?
Sometimes, particularly after treatment. Long-standing sensitivity usually has an ongoing cause that will not resolve unaddressed.
Does it mean I have a cavity?
Not necessarily, but it can. Generalised sensitivity across many teeth is usually recession or erosion; sensitivity in one tooth deserves a closer look.
Get the cause identified
Sensitivity has several causes and they need different treatments. See our general dentistry page.
To arrange a consultation at our clinic on Abbas El-Akkad in Nasr City, call +20 101 969 7597 or message us on WhatsApp.
