The remaining teeth came out with the mandible section which was removed.
It would be excellent to have one or perhaps two family members with you the morning of surgery. It is usually very early prep. After you are wheeled into surgery the family member(s) can wait in the waiting area and they will be updated of your progress. That being said, the surgery usually takes eight hours plus or minus so the family might want to go back to the hotel for a bit.
After surgery you will be in recovery for an hour or so before you are wheeled up to your room on the other side of the hospital. It is there you can see family but you may not want much company for a day or three. You will feel poorly and have tubes from several places. You will only be able to write on a white board because you will have a trach tube to breath at least for a day or so.