Hello, I need some advice, Dr Shaffie. I had a root canal done by my general dentist and while in the process of getting it done she placed a piece of cotton wool inside my tooth and covered it with a hard substance. Now my tooth is throbbing and killing me and when I bite down I feel something moving away in my tooth and it’s very painful. I asked around and I was told she was not supposed to use cotton and I that this could cause some kind of infection. I was told to go to the emergency room immediately and have them remove the cotton to avoid tooth infection. Is this really true?