Why a tooth can become sensitive after having a filling.
For some people their tooth can become sensitive for a days to weeks after having a filling. There are many reason why this can happen but the most common reason is that part of the tooth and all of the dental decay must be removed for a filling to be placed. In some cases, this procedure can cause sensitivity in the tooth. As a general rule, the deeper the cavity and closer to the tooth nerve, the more likely there will be discomfort after the dental procedure. If the pain last for over a week it is advise to go back to the dentist to have the tooth re-evaluated.