Sensitive Teeth to Cold and Sweet: Causes and Treatment

Why are teeth sensitive to cold and sweet?

A tooth has a hard outer layer, the enamel, and beneath it the dentine, which contains tiny channels leading to the nerve. When these channels are exposed, cold and sugar travel quickly to the nerve and cause a sudden jolt of pain. Common causes include:

• Enamel erosion from acids or hard brushing.
• Gum recession exposing the roots.
• Grinding or clenching the teeth during sleep.
• Decay, a worn old filling or a cracked tooth.
• Temporary sensitivity after whitening, cleaning or a new filling.

Enamel erosion: how to protect your teeth from acid

Enamel does not grow back once it is lost. One of the most damaging habits is frequent acidic drinks such as soft drinks, energy drinks and some juices, especially when sipped slowly through the day. Frequent acid reflux can also cause visible wear on the inner surfaces of the teeth.

To limit the damage, have acidic drinks with meals rather than between them, use a straw when you can, and rinse with water afterwards. Do not brush straight after acidic food or drink; wait about an hour so saliva can restore balance in the mouth.

Gum recession and exposed roots

Tooth roots are not covered by enamel; they are protected by the gum. If the gum recedes because of periodontitis, hard brushing with a stiff brush, or simply with age, the root surface is exposed and becomes very sensitive to cold and touch.

Sometimes a small notch forms at the gumline, often linked to hard brushing and clenching. Treating the cause matters as much as treating the sensitivity, so the recession does not continue.

Sensitivity after whitening or fillings

Sensitivity during and after whitening is common and usually temporary, settling within a few days of finishing treatment. Your dentist can adjust the session length or gel strength, or suggest a sensitivity toothpaste before and after whitening.

After a new filling, mild sensitivity for several days to a few weeks can occur. But pain that is severe, lingers long after the cold has gone, wakes you at night or appears when you bite may point to a nerve problem or a cracked tooth and needs to be checked.

How can you ease sensitivity at home?

In mild cases these steps help, and they usually take 2 to 4 weeks of regular use to show their effect:

• Use a sensitivity toothpaste twice a day, such as those containing potassium nitrate or stannous fluoride.
• After brushing, spit out the toothpaste without rinsing heavily so it keeps working.
• You can dab a little toothpaste on the sensitive spot with your finger before bed.
• Use a soft brush and gentle movements, and avoid pressing hard.
• Cut down on acidic drinks and frequent sugary snacks.

In-clinic treatments for sensitivity

If home care does not help, your dentist will first find the cause and then choose the right treatment, which may include:

• Fluoride varnish or materials that seal the exposed dentine channels.
• A tooth-coloured filling to cover an exposed root or a notch at the gumline.
• Treating decay or replacing a worn filling.
• A night guard for people who grind their teeth.
• In some cases of marked recession, a gum graft to cover the root.
• If the pain comes from the nerve itself and other options have not worked, root canal treatment may be needed.