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Good thoughts!
So as a skeletal objective to the maxilla we have a spectrum of options:
In the growing patient we can try growth modification – holding (vertical and/or horizontal with various levels of force), reverse pull headgear, or the “headgear effect” that we get from some appliances.
In the non-growing patient we decide surgical or non-surgical.
So first question – is the protrusive or not? Based off N Perp A and the cranial base adjusted SNA, I agree that it is protrusive.
The second question – do we treat it? Is it one of our objectives? In order to answer this I consider the patient’s concern, facial esthetics and surgical options. For this patient, I like the rough esthetics of the maxilla, it is ethnically appropriate and harmonious with her face.
Surgically there is not a great option to move the maxilla posteriorly in the AP. There is an anterior segmental osteotomy procedure that is seen mostly in Korea and there is a premolar transpalatal osteotomy discussed in Proffitt’s surgical textbook. I’ve not found an oral surgeon that does either of these procedures…and I’ve had a couple cases where it could have helped! So for these reasons in the AP direction with the maxilla it’s conventionally either hold/leave it alone in the AP or Advance it.
(Side note here, in practical terms even if you say “hold” in the AP and you are downfracturing the maxilla for some other goal (rotation, cant, or expansion) then the surgeon can’t place it exactly back in the same AP – the pterygoid plates will get hung up and it’s pretty challenging to clear the bone requried. So even in a “hold” situation once the down fracture happens your going to have about a 2mm advance)