Please don't be afraid of a root canal treatment. It is absolutely harmless. There are a various methods of reducing pain before, during and after your root canal treatment. Often a premedication helps during your root canal treatment combined with a good amount of anesthesia and the right techniques. Laser root canal treatment is also possible these days but is slightly costlier. Rubber dam is one of the best way to avoid ingress of all the microbiota into your canals so please do not be afraid of it. It's absolutely painless.

Do not worry. Just have your pre and post medicines as prescribed by the doctor. You will be fine. You will be given a local anesthesia and root canal will be done painlessly. Talk to your doctor openly about your fear and anxiety, doctor will help you overcome that. Please go through the post in the link mentioned below.

There are a few steps in root canal treatment .. And making the patient pain-free giving anesthesia to numb the tooth is the initial one.. Rubber dam is another step just for keeping sterile environment while working which is also comfortable.

Root canal is not painful. We give anesthesia on first sitting so the pain is not felt. Next sittings r without anesthesia as the nerve is removed . Nerve is the tissue that conducts pain stimuli to brain. Once nerve is removed there is no connection  with the brain . Rubberdam  is used for isolation of the tooth. Fixing a rubberdam is also not painful. Root canal can be done without fixing a dam.