If you wince with pain after sipping a hot cup of coffee or chewing a piece of ice see your dentist. You may be suffering from "dentine hypersensitivity", more commonly known as sensitive teeth or a hole in your tooth or abscess that is not yet visible.
Sensitive teeth may be the result of gum disease, years of unconsciously clenching or grinding your teeth, or improper or too vigorous brushing (if the bristles of your toothbrush are pointing in multiple directions, you're brushing too hard).
Abrasive toothpastes are sometimes the culprit of sensitive teeth. Ingredients found in some whitening toothpastes that lighten and/or remove certain stains from enamel, and sodium pyrophosphate, the key ingredient in tartar-control toothpastes, may increase tooth sensitivity.
In some cases, desensitising toothpaste, sealants placed by your dentist, mouth splints to decrease grinding or decreasing the intake of acid-containing foods can alleviate some of the pain associated with sensitive teeth.
If a sensitive tooth is due a cavity, pulp disease or an abscess that is not yet visible you may require a filling or perhaps root canal treatment to resolve the problem.
In any case, contact your dentist if you notice any change in your teeth's sensitivity to temperature.