You brush with too much gusto. Sometimes tooth sensitivity comes from brushing with too much force or with too hard-bristled a toothbrush. Over time, you can wear down the protective layers of your teeth and expose the microscopic hollow tubes or canals that lead to your dental nerves. When these tubules are exposed to hot or cold or to acidic or sticky foods, tooth sensitivity and discomfort can be the result. The simplest solution is to switch to a toothbrush with softer bristles and to be gentler when brushing.
You eat acidic foods. If the pathways to your nerves are exposed, acidic foods such as tomato sauce, lemon, grapefruit, kiwi, and pickles can cause pain. Use common sense: Stick to foods that won’t cause you pain.
You’re a tooth-grinder. Grinding your teeth can wear down the enamel, even though it’s the strongest substance in your body. By doing so, you expose the dentin, the middle layer of the tooth, which contains the hollow tubes that lead to your nerves. Talk to your dentist about finding a mouth guard that can stop you from grinding. The best guards are custom made to fit your bite, Dr. Seldin says.
You choose tooth-whitening toothpaste. Many manufacturers add tooth-whitening chemicals to their toothpaste formulas, and some people are more sensitive to them than others. If your toothpaste could be to blame for tooth sensitivity, consider switching toothpastes.