Within 3 days a tooth should settle down after a filling. This will take longer if your tooth was sensitive to start off with prior to the filling. After week, more or less things should go back to normal and you should be able to bite it and eat hot or cold things as normal. White tooth coloured composite fillings and inlays/onlays tend to be more sensitive afterwards than amalgam fillings. In addition a large and deep filling will be more sensitive compared to a shallow filling which may not have even needed an injection to do the treatment in the first place.

A replacement filling may have been deeper than the original filling due to decay which has to be removed first. In this case it is probably likely that initially you will get some sensitivity however dentists place something called a “lining or bonding agent” under a filling and that reduces sensitivity hence over a period of time, any sensitivity will go away.  Continuous discomfort or sensitivity which is becoming worse can indicate that the tooth needs examining again.

Severe sensitivity can cause pain in other teeth as it can be difficult to pinpoint. The sensitivity may appear in the adjacent tooth or even the tooth in the opposing jaw. There can even be times when the sensitivity is particularly bad and it appears the whole set of teeth can become sensitive. This is usually called referred pain.

Infection under a filling is characterized by continuing severe pain especially at night when lying flat. The pain can start if you have something hot, cold or sweet but it continues afterwards as well.  The pain may last for five minutes or for several hours. Another sign to look out for is spontaneous pain.  This is when pain from the tooth just occurs for no reason.  Finally if infection has the progressed into the root you will get pain on biting and there may also be swelling on the gum around your infected tooth.

After a filling it can be normal for your tooth to hurt as work as work has been done on it and the injection is wearing off. Normally for the remainder of the day and the next day you will be aware of a dull ache.  You may also get an uncomfortable feeling when you bite fairly hard on the tooth.  Your tooth can hurt for a few more days afterwards especially if the filling was extensive and deep in the first place. Normally your dentist would have warned you about this in any case and what to do about it.

A tooth can hurt worse after a filling especially if the filling was quite deep or it had extensive dental decay.

If your tooth still hurts after taking painkillers and it has been more than a week then you should go back to see your dentist to have it re-examined. Your dentist may even take an x-ray especially if the filling was close to the nerve to make sure there is no infection.

A filling can be placed close to the nerve without any problems as long as the technical procedures in carrying out the filling have been applied correctly. However teeth being biological tissues can be unpredictable and sometimes a filling very close to the nerve can cause irritation to the nerve.  Sometimes the nerve can recover however other times it is necessary to carry out another procedure called a root canal treatment or a pulp cap.

Constant throbbing after a filling can indicate that the nerve is infected and will not recover. In these cases the dentist will carry out tests and an x-ray. If there is infection, then you have the option of having a root canal or an extraction. This choice depends on cost, the dentist’s opinion and your wishes.