If your teeth hurt whenever you have hot food or cold drinks, that’s usually caused by the outer covering of your teeth getting worn out. If these outer coverings become too thin, the nerves inside your teeth get more closely exposed to what you eat or drink.
Each of your teeth’s nerves are covered by a fairly sensitive layer called dentin, and dentin is supposed to be protected by the hard enamel layer that makes up a tooth’s crown. Meanwhile, what’s covering the dentin in the part of a tooth that’s hiding underneath your gum is called cementum.
Keeping your teeth clean and well-maintained prevents issues like cavities and gum disease from wearing out the cementum and enamel and making your teeth likely to feel painful sensations. However, even if your teeth do become sensitive, your dentist can treat the issue regardless of whatever problem caused it.