Why Are My Teeth Sensitive to Hot and Cold Foods?

A short, sharp sensation after a sip of cold water or a hot drink is a common reason people ask about sensitive teeth. The feeling may come from one tooth or several, last only a moment or continue after the temperature trigger has gone. The pattern is useful information but not a diagnosis.

If your teeth are sensitive to hot and cold, a dental check-up can help identify whether the cause is exposed dentine, tooth decay, a crack, a restoration, gum changes or another issue.

How does tooth sensitivity happen?

Enamel forms the hard outer surface of the tooth crown, while cementum covers the root. Beneath these layers is dentine, which contains microscopic tubules leading towards the dental pulp. When dentine becomes exposed or the tooth is damaged, temperature changes may stimulate the tooth more readily.

Possible reasons teeth react to hot and cold

Enamel wear or dental erosion

Acid from food and drinks, reflux, repeated vomiting or some dry-mouth conditions can gradually erode enamel. Dental erosion may make teeth look smoother, thinner or more yellow and may contribute to sensitivity.

Gum recession or exposed root surfaces

When the gum margin moves away from part of a tooth, the root surface can become exposed. Possible contributors include gum disease, tooth position and brushing habits.

Tooth decay

Tooth decay can produce sensitivity as acids from plaque damage the tooth. Other possible signs include toothache, visible spots, pain when biting, or red and swollen gum near a tooth.

Cracks, worn restorations or a recent procedure

A cracked tooth, chipped area, worn dental filling or a restoration that no longer seals as intended may allow temperature changes to reach sensitive tissues. Temporary sensitivity can also occur after some procedures.

Changes inside the tooth

Inflammation or infection of the dental pulp can cause temperature sensitivity, sometimes with lingering pain, spontaneous toothache or swelling. These symptoms require timely assessment.

When should sensitivity be checked?

Arrange a dental assessment when sensitivity is new, persistent, worsening, limited to one tooth, or interfering with eating and drinking. Seek advice sooner if there is lingering pain after a hot or cold trigger, pain when biting, a visible crack, a lost filling, gum swelling, facial swelling, fever or a recent injury.

Daily habits that may help protect sensitive teeth

• Brush twice daily with a soft toothbrush and fluoride toothpaste, using gentle pressure around the gumline.
• Clean between the teeth each day using a method recommended for you.
• Limit frequent acidic drinks and snacks. Water is a tooth-friendly choice between meals.
• After acidic food, drink, reflux or vomiting, rinse with water and wait at least 30 minutes before brushing.
• Ask a dental practitioner whether a toothpaste for sensitive teeth is appropriate for you.

What may happen at an appointment?

The dental practitioner may ask which foods trigger the sensation, how long it lasts and whether you have pain when biting. They will examine the teeth, gums, bite and existing restorations. Temperature or tapping tests and dental X-rays may be recommended when clinically indicated.

Treatment is based on the cause and may include personalised home-care advice, professional fluoride or other desensitising measures, repairing decay or a damaged restoration, managing gum disease, protecting a cracked or worn tooth, or discussing treatment for the dental pulp.

General information only: This article is not a diagnosis or a substitute for advice from a dental practitioner who has assessed you. Treatment needs, benefits, risks, alternatives and likely outcomes vary between people.