In the past, I had 2 root canals with not problems!!! about 3 yrs ago, my niece, who worked for a dentist , had a toot canal, by that dentist. within a yr, she started numbness on that side of face, trouble eating,,drooling to the point that she became withdrawn from people because of embarrassment....she cannot eat & has lost wgt. from 165lbs to 104lbs.....many drs., several hospital stays & is close to death... What do you think could be problem? She is close to death as we speak & in hospital, but so far.....really bad health care!!!