I have a big hole in my tooth it doesn't hurt and not sensitive do i need root canal like doc said?

CHECK with dentist: If there is a hole i guess it needs to be filled--ck with the dentist.

Pain: You've made the wrong assumption: you assume that you need to be in severe, intolerable pain for something to be amiss. Not true. Your dentist diagnosed your problem with the help of a radiograph and years of experience. If you would like a second opinion, seek the opinion of another local dentist who can actually examine you. Waiting until the tooth hurts may result in its loss due to decay.

Probably: Just because you have no pain doesn't mean you don't need a root canal! If the decay is close to or into the pulp chamber, a root canal in necessary!

Root canal: If a tooth can be saved with a good prognosis, the root canal is the treatment of choice. Your dentist will check, evaluate and offer advice specific to your individual situation.

Second opinion: Normally, if a dentist recommends a root canal, it is needed. If the pain goes away, that does not mean that the tooth does not need a root canal. If in doubt, get another opinion.