“Why does my tooth hurt after a deep filling?”

Oftentimes, a deep cavity may be closer to the nerve that we think, but the dentist can't start a filling and leave tooth decay there. The decay may have been all removed, but the nerve may have been agitated. Thermal changes, especially if a base wasn't applied and you opted for a silver filling, may cause discomfort. Also, if the filling is high, or hyper-occluded, biting or cold may cause discomfort. Some, but not all, deep fillings can lead to a root canal, or more extensive treatment. This should have been explained to you in your Informed Consent paperwork. Seek a follow-up appointment with your dentist as soon as possible to prevent further damage.
Hope this helps.

Warmest regards,

E.D. McDonald, DDS Mba

Unfortunately it can be normal for a tooth to hurt after a deep cavity has been removed and filled. The live pulp tissue in a tooth can become inflammed by the deepening cavity before a dentist can fix it despite not feeling any pain prior hand. As we drill, blow air, expose the tooth to chemicals like an adhesive, further inflammation can occur now causing it to hurt. The tooth will also have to adjust to having an artificial material stuffed into it. Bottom line, most fillings only hurt for a few days post op. It can last months but as long as you can bite down and pain does not linger when in contact with hot/cold, the tooth should not need a root canal. If pain does linger for 10sec or more or simply hurts on its own, it likely needs a root canal.