How is an abscessed tooth diagnosed?
Your dentist will probe your teeth with a dental instrument. If you have an abscessed tooth, you will feel pain when the tooth is tapped by the dentist's probe. Your dentist will also ask you if your pain increases when you bite down or when you close your mouth tightly. In addition, your dentist may suspect an abscessed tooth because your gums may be swollen and red.
Your dentist may also take X-rays to look for erosion (wearing away) of the bone around the abscess.