I have a small hard lump straight above second to back upper rear molar. It is at the level of where the root of the tooth would be and is sore if you prod it with your finger . A dentist recently looked at the tooth which is predominantly filling, an x-ray that did not show anything obvious. What do you think is causing this I have had this for a few months now, sometimes it is more sore to touch than others.
Hello and welcome to Chat Doctor, Swellings or hard lumps in relation to upper molar tooth which is already filled suggests some kind of periapical or periodontal infection. Filled tooth may have undergone infection due to residual caries or root caries leading to periapical lesion that may even touch the sinus floor, but this is visible in the x-rays. If x-ray is already been taken with no visible changes then I feel the swelling is due to gingival infection which can be cystic or gingival abscess. You need to visit a dentist, deep cleaning and root planing of the gums along with the course of medication will solve the problem. Take care.