I have had 6 root canals performed by Dr. Endo; 4 of them being emergency root canals b/c the teeth had severely abscessed. There is absolutely NO pain on this earth like an abscessed tooth. Dr. Endo is a GENIUS; he alleviated me from this truly unbearable pain nearly painlessly. I was anticipating the pain to get worse when I sat down in the chair but it was surprisingly less painful than getting a cavity filled. He is very nice and gentle. Very nice office staff as well.