Brief Answer:
tooth infection, medicines, RCT, Extraction

Detailed Answer:
Thanks for your query, I have gone through your query.
As far as the pain in the tooth is concerned, it is because of the infection in the root tip of the teeth secondary to decay.
Nothing to worry about the pain, you can take a course of antibiotics like amoxycillin and analgesics like diclofenac(if you are not allergic) after consulting the oral physician. These medicines will bring down the infection and pain.

If the teeth have sufficient tooth structure left out in it, then it can be restored with root canal treatment and can give a cap over the root canal treated tooth. If the tooth is too weak, then it has to be removed or extracted. Following extraction, the dentures can be fabricated.
If possible, try to save the tooth, because the artificial teeth(dentures) will not give strength of a natural tooth.
Do not get scared about pain, all the procedures are done under local anesthesia, it will be completely painless.

These are the possible causes, diagnosis and treatment plan based on your description of the lesion. If you can upload the images, i can tell you whether you can save the tooth or it needs to be removed.
If any queries are there reply me back.
I hope my answer will help you, take care.

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Brief Answer:
Go ahead with the treatment.

Detailed Answer:
Thanks for your feed back.
Nothing to worry and no need to get scared. Go ahead with the treatment. Be bold.
Take care.

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