Iced coffee, a spoonful of ice cream, a cold morning walk with your mouth open, and there it is: a quick, sharp zing that makes you wince. Patients mention it at checkups all the time, often apologetically, as if it's not worth bringing up. It is. Sensitive teeth usually have a clear cause, and most of the time something simple helps.
What is happening inside the tooth
Under the enamel and below the gumline is a layer called dentin. Dentin is full of microscopic tubes that lead toward the nerve. When enamel wears thin or the gums pull back, those tubes are exposed, and cold, heat, sweets or acidic foods can reach the nerve through them. The result is short, sharp pain that fades once the trigger is gone.
The most common causes
- Receding gums, which expose the root surface. Root surfaces have no enamel, so they are especially sensitive. See gum recession treatment.
- Brushing too hard or with a hard-bristled brush, which wears away enamel and gum tissue at the gumline
- Acidic foods and drinks such as soda, sports drinks, citrus, kombucha and wine, which soften enamel
- Grinding and clenching, which wears teeth down
- Tooth whitening, which can cause temporary sensitivity
- Recent dental work, such as a new filling or a cleaning, usually short-lived
- Gum disease, which causes the gums to recede
When sensitivity is a sign of something else
Sensitivity limited to one tooth, pain that lingers for more than a few seconds after the cold is gone, pain when biting, or a throbbing ache that wakes you up aren't typical sensitivity. They can point to a cavity, a cracked tooth, a failing filling or an inflamed nerve. These need to be checked rather than treated with toothpaste. Read about cracked tooth symptoms.
What helps at home
- A desensitizing toothpaste with potassium nitrate or stannous fluoride, used twice a day for at least two weeks. It works gradually, so give it time.
- A soft-bristled brush and gentle pressure. Electric brushes with a pressure sensor help heavy brushers.
- Waiting about 30 minutes after acidic foods or drinks before brushing.
- Drinking acidic drinks with meals and rinsing with water afterward.
- Spitting, not rinsing, after brushing at night, so the toothpaste stays on the teeth.
What your dentist can do
- Apply a fluoride varnish or desensitizing agent to sensitive spots
- Cover exposed root surfaces with bonding
- Recommend a prescription-strength fluoride toothpaste
- Treat gum recession with a gum graft in more advanced cases
- Make a night guard if grinding is the cause
- Fix a cavity, crack or leaking filling if that is what is behind it
Your dentist will first look for the cause during a cleaning and exam, so the treatment matches the problem.
Sensitivity and whitening
If whitening makes your teeth sensitive, it usually settles within a day or two of stopping. Using a sensitivity toothpaste for two weeks beforehand, and spacing out treatments, can help. See how long teeth whitening lasts for more on planning whitening.
When to book a visit
Give a sensitivity toothpaste two or three weeks. If it hasn't helped, if it's getting worse, or if it's one tooth in particular, mention it at your next visit or book an exam sooner. It's usually an easy fix once we know the cause.
