Each case is unique!
The surgery is anticipated or prorogated according to the kind of problem.
For instance: if the chin is too far forward (prognathism), it is better
to wait until the growth phase is ended and then to have the surgery done,
with the aim of avoiding risks of relapse. On the other hand, if the chin
is underdeveloped, the surgery can be anticipated. The best age keeps being
the young adult, though we have been treating young teenagers and adults
over 40 years old without any problem.