I think it depends on the bone. A finger can be fully healed in 3-4 weeks.
Jaw is usually 3 months.
Surgery on the jaw takes a full year for all the swelling, etc to subside. But the bone should be healed by 3.
When I consulted with Gunson, he seemed to have a very conservative view on this. He said something like "no mouth guard" etc for one year after surgery, meaning so scuba diving etc (told him I did this because he asked me about my sinuses and I said I have no problem equalizing while diving). This scared me a bit, does he really mean that the jaw isn't healed and can be trusted to stay in place until after 1 year? If I can't even go scuba diving, how can I then start eating normal earlier?
I remember when I went to see a doctor for a suspected fracture in my finger and I had waited 2 weeks. He told me there was nothing he could do about it, the only thing he can do after 2 weeks would be to re-fracture it, because it was already healed.
3 months sounds much more reasonable with respect to what time other fractures take to heal.