What exactly is the growth which occurs in face before 17yrs of age for which SMR is C/I?

what exactly is the growth which occurs in face before 17yrs of age for which SMR is C/I? Thus in acromegaly there should not be prognathism or frontal bossing kind of features… Please explain.

I think as development of secondary Ossifying centres complete by 17 years that’s why

The secondary ossification centres are present at the lower part of septum and maxilla and are responsible for the growth of the midface , which if damaged can lead to mid facial abnormalities