There are multiple reasons for the pain and abscess associated with previously root canal treated tooth. Sometimes the nerve and dead tissue was not completely or thoroughly removed. Sometimes an entire canal is missed because it did not get spotted during the initial checkup etc. Thorough clinical and radiographic examination will be necessary to determine the exact cause of abscess and suitable treatment option.

Good afternoon mam, I have gone through your description. This is might be due to reinfection in your root canal treated tooth. You should get a dental xray done to identify if there is any reinfection in Root canal treated tooth. Or have infection in any other tooth. For pain relief and infection control you can take Capsule Mox 500Mg 3times a day for 3 days. Tablet Brufen 400mg 3 times a day for 3 days. Avoid medicines if you have allergy from penicillin and ibuprofen.

If you are having pain while chewing on RCT treated tooth, then might be it's a case of reinfection. X ray will be helpful to diagnose the problem and it's extent. Visit some clinic or video consult.

Hello dear Please be calm See it seems to be a abscess due to endodontic infection.you  will require medications also and later curettage or  drainage could be required.for further details you can consult me Thanks

Greetings, Maam i have gone through yiur description it seems like you need to go for re rct but with x ray we can comfirm the diagnosis and your treatment plan Till then if it causes pain you can take medicines also. For prescription you can contact me. Hope this will help you.

Prosthetic crown should be removed immediately(so that tooth is removed from occlusion) Some medicines can be prescribed after that

From your description and symptoms it sounds like you will need to repeat RCT for that tooth. An X ray might be required to confirm the diagnosis. Meanwhile, you can start warm saline rinses as many times as you can in a day. An over the counter painkiller will also help in case you develop pain.

You might need to take an Xray to determine the status of the Root canal done teeth. Presently you can go along with warm saline gargle and gum massage till the covid situation normalises