Depending on the severity of the cavity, prior to getting a filling the dentist may put medication into the tooth to disinfect or treat the cavity. In some cases medication is put into the tooth to clear it up and sometimes medication can be used to protect the pulp.

Why is medication used?

Not all cases require medication to be used and will depend on the severity of the dental cavity. If the cavity is rather small and not deep then removing the decayed area and disinfecting the area once and then filling the tooth is adequate. If the cavity is deep and is close to reaching the pulp then medication will have to be used to protect the dental nerves, medication will have to be put into the tooth between 2 to 3 times, once the symptoms have cleared then the tooth can be filled.

If the dental cavity is severe and has already reached the dental nerves there is the possibility it could develop into Apical periodontitis which will require medication to put be inside the tooth kill microbes and dissolve pulpal tissue. This could take up to 1 week to be complete and requires medication inside the tooth to be changed every 2 days.

Though patients should be aware that even with the use of medication to disinfect the tooth within there will still be pain. Deep dental cavity pains may subside over a few days once the medication has been inserted, however if the pain gets worse then you should contact your dentist immediately.

If the decay has already reached the dental nerves then the insertion and disinfection of tooth then the toothache will be more severe. Once the root canal infection has been cleared the pain will subside.