Sensitive teeth can be such a pain, especially on a cold day but they are easy to fix. Sensitivity is usually caused by root and nerve exposure where the gum has receded away. The dentist can place a protective covering over these teeth which stops anything hot or cold getting to the nerve. Another tip is to use a daily toothpaste specially designed for sensitive teeth. On really sensitive teeth a dab of toothpaste placed over the area overnight will also help.
Many people experience sensitive teeth at some point and the usual triggers are hot and cold. Teeth become sensitive due to the gums receding away from the teeth exposing the roots and nerves. When exposed to pressure, hot and cold these nerves cause pain. Having a protective covering placed over these areas will help with the sensitivity and also using a toothpaste especially for sensitive teeth.