I had root canal treatment 3 weeks ago and since cannot eat without pain and aching in my jaw and also the side of my face is numb.  I went to see the dentist a week ago and he said it was nothing to do with the root canal and if persists he will have to refer me???? I am going back to see him tomorrow but need to understand what can be done.
Which tooth was operated ? Was it the last molar in the lower jaw ? Though root canal doesn't have any effect on jaw, a variety of other factors may be causing your problem. Contact of needle to a nerve trunk may cause numbness. Relax, it will take time but is self-healing. For e.g. opening your jaw too wide, infection related to the third molar of the lower jaw. Treatment is symptomatic after ascertaining the cause.