You can see in the xray I have a tooth on my lower jaw.. what is this called? Canine tooth? Should I remove it, I MUST remove it? It looks like a pretty hard operation
Answer Yes, it is your lower left canine. Unless it was causing you serious problems, I would leave it alone. There may be resorption of the apices of a couple teeth; these should be pulp tested to see if they are still vital. I can't examine you, so I can't really assess the situation. I would visit an oral surgeon with a cone-beam 3-D x-ray machine. That would tell a lot more about whether it is causing problems with the other teeth and how difficult the extraction would be. On the other hand, if the apices are resorbed already and the pulps in the teeth are non-vital, the damage is already done, and they simply need root canal therapy. So, the decision is a little complicated and I can't make it for you on the basis of just an x-ray.
I can answer your questions about root canal therapy in general. PLEASE DO NOT ask me to diagnose your particular problems or recommend treatment as I cannot do this without examining you and seeing your x-rays.
I am a Board-certified endodontist, former university department Chairman, teach dental residents, and have a private practice.