But another told me that if the root is too difficult to pull
out (impacted, etc.) he would choose to leave the inaccessible piece of the root
in place, especially if it is too close to the nerve.
What problems can a piece of root left behind cause, after an extraction, in the short-term and later on?
And what are the pros and cons of leaving the piece of root in place, if its extraction would otherwise entail possible severance of the nerve, and/or a lot of bone-cutting?