There was a post on the facebook group where someone wrote how her surgeon warned her she might look like a 'monkey', and everyone in the group was completely outraged, like how dare this surgeon say she will look like a monkey! He was unapologetically honest though. Obviously he couldn't do CCW to avoid it, lol but at least he warned her.
Do you think a 3d/VSP soft tissue mask would show a chimp lip, if it were going to happen?
I really want to avoid that at all costs. I don't trust 2d plans to show it.
Well, with a significant maxilla advancement, a surgeon CAN predict the chimp lip even without high tech software. Chimp lip is consistent with linear advancement cases where for the mandible to go 'forward' enough or a lot, so does the maxilla, usually cases where mandibular displacements are prioritized either for airway issues or just significant retrusion. Cases where what happens to the maxilla profile component (nose base, upper lip area) would be considered a trade off (negative aesthetic one) in exchange for the wanted/needed mandibular displacement.
With CCW (posterior downgraft), the whole mandible kind of gets a 'free ride' and the 'advancement train' even before they do the BSSO. So, maxilla advancement is minimized and mandible advancement maximized.
Since there does seem to be a correlation between docs who DO CCW (posterior downgraft) and who do so to avoid using linear advancement WHEN it might have negative aesthetic consequences (to avoid chimp lip), I would suggest consulting with those types.
The 2D diagrams, at least ones I've seen out of Gunson's office that show the planned contours of the profile which DO have a focus on the lip contour, seem ok to me. Those are Nemo FAB Arnett analysis type. But other docs use similar and I guess adjust according to their own aesthetic preferences.
