Normal healthy teeth have a nerve within the center of the root that can sense hot and cold. When you have ice cream and it lingers on your front teeth, it is these dental nerves that sense the cold.
It is fairly common for teeth to become hypersensitive to cold. If you have receded gums and your roots are exposed, it is very likely that this could be the cause of the cold hypersensitivity. The first aid home care for receded and sensitive roots is to begin using a desensitizing toothpaste. Avoid toothpastes that are advertised as “tartar control”, “whitening”, or “total” toothpastes. Surprisingly, the biggest cause of cold sensitivity is using these toothpastes. Bleaching and tartar control additives seem to affect receded roots to cause cold sensitivity, and to a lesser extent sweet sensitivity.
Typically it takes three or four weeks using desensitizing toothpastes to decrease or eliminate root sensitivity. If cold sensitivity is not improving, and certainly if it is getting worse call your dentist to check the teeth. An x ray and temperature testing can usually determine if there is another cause for the sensitivity such a decay, a leaking or fractured
filling, or tooth fracture.
There are some patients with recession that do not respond to desensitizing toothpastes and have no decay, filling or fracture problems. If this is your situation ask your dentist about other desensitizing treatments such as fluoride varnish or bonding resin on the
sensitive root areas. Heavy handed brushing with a hard brush, and acidic foods in the diet are also factors that contribute to cold sensitivity.