Sensitive teeth: causes and what helps

What sensitivity is

Each tooth has a hard outer layer of enamel. When the enamel wears down, or the gum pulls back and exposes the root, the softer layer underneath (dentin) is uncovered. Hot, cold, sweet or sour food and drink can then reach the nerve inside the tooth, which is why it hurts.

Common causes

• Acidic foods and drinks such as citrus fruit, tomatoes, pickles and tea
• Brushing too hard, or with a hard toothbrush
• Gum recession, which exposes the root
• Gum disease
• A cracked or chipped tooth
• Grinding your teeth
• Tooth decay
• A recent dental treatment, or some whitening products and mouthwashes

What helps at home

• Use a soft-bristled toothbrush and brush and floss gently every day.
• Use a desensitising toothpaste, and apply a little to the sensitive areas before bed.
• Cut down on acidic foods and drinks.
• If you grind your teeth, ask about a mouth guard.

What a dentist can do

Your dentist will first look for the cause, since sensitivity can be a symptom of something that needs treating, such as a cavity, a crack or gum disease. Depending on what is found, treatment can include bonding to cover exposed roots, a sealant on the exposed dentin to block the pain signals, and a fluoride varnish to strengthen the enamel.

When to book

See a dentist if the sensitivity keeps coming back with hot, cold or sweet things, and sooner if the pain is sharp or getting worse. Sometimes sensitivity goes away by itself, especially after a dental visit, but it's better to find out why than to wait and see.