Hi again Kavan!
From memory I think you're right, the tilted pose was to free up my airway so to speak!
The problem I have is that I've lost as much weight as I reasonably can but the fat neck isn't reducing at all (I've weighed heavier in the past and lost around 40lbs over the last couple of years and it's remained).
It's this that led me to think it must a recessed jaw etc causing it, but I'm now certain it's just more a genetic thing.
In this case would something such as a chin implant or sliding genio alongside liposuction of the neck help me would you say?
AHA. So I guessed right as to what that chin in a cup pose was for and in the absence of any prior familiarity with seeing something like that on this board before or KNOWING prior what it was for. I guessed it right because there was something about about the 'back and forth' with GJ about CCW vs linear advancement that allowed me to question myself as in: 'How could Kavan POSSIBLY be wrong about something?' Well, the answer to that usually resolves to being THROWN FOR A LOOP.
My not getting it right in the first place usually resolves to absence of information of some kind. Often by an ASSERTION the OP makes within their question. For example, the 'chin in cup' scan,in absence of info that a full ceph X ray would yield, and NO MENTION from you as to what it was actually for. Also the assertion from you, WITHIN YOUR QUESTION, that your face was recessed in addition to your assertion the apnea was due to face recession.
So, you got both GJ and me to accept apriori your assertion of recessed face and then we are going back and forth as to the pros and cons of linear advancement vs. CCW on the basis of a LOW MPA which at first glance is low on the chin in cup scan.
That is exactly happened with your presentation. I mean IF you had told us IN THE FIRST PLACE that the chin in a cup pose was to free up your air way SO they could actually LOOK at it, I would have had the CLUE, right then and there that the most likely reason for that to be done would have something to do with it being 'squeezed on' in a normal head position usually used in a ceph for bimax evaluation. OK.
Anyway, your case would most likely resolves to a NECK EXPERT, a plastic surgeon conversant in correcting all the DEEP structures of the anterior triangle of the neck which include MORE structures than just the superficial fat pad and superficial platysma muscle. You could have fat very DEEP to the superficial fat pad in addition to multiple other anatomical structures DEEP to the neck that need to be altered or reconstructed to correct the salient AESTHETIC problem; OBTUSE cervicomental angle, and/or 'difficult neck' which is something in the venue of plastic surgeons very conversant in altering those structures. So there is probably MUCH more going on under chin/neck than would be corrected via a superficial fat pad being lipoed out and a chin implant being put in.
However, most of my time and focus here has been redirected into cross referencing whether or not you REALLY had a recessed FACE. So you need to establish/confirm that your airway, itself is large enough and the MEDICAL matter at hand is the excess neck tissue 'squeezing' on it in neutral/normal head posture and especially when sleeping and not one where the airway is actually small. You did not convey whether or not the MEDICAL findings of that confirmed small airway or impinged on airway.
On the basis of SALIENT aesthetic problem and the the morph I did prior, I put in where a TVL would be found (true vertical line) and found you basically had the right jaw to jaw line up with reference to it. No significant chin recession was found. However, you could get chin advancement to be closer to the drop down line but still somewhat behind it (most certainly not beyond it). So, when I alter the FAT NECK issue, there is no salient facial recession there for me to further suggest or imply to suggest that bimax advancement would be the 'solution' to your key aesthetic problem. Hence, more likely than not, your aesthetic issue is in the venue of a plastic surgeon conversant in correcting all the very DEEP structures UNDER the chin and neck. OBTUSE cervicomental angle, 'difficult neck'.