U shape after BSSO

[timang]

I reckon most of us would like to have a defined V shaped lower third. I think it's very rarely achievable via BSSO but sometimes it results more pronounced bulky, U shaped lower third.  What is the cause for that?

[Tiny]

@polynesian I think you're misunderstanding, he doesn't mean a tapered jaw, he means a defined jaw.  You can have a tall ramus, and have a V-shape rather than U-shape in the chin area (in fact it's usually the case)

For these pics it's hard to say but it's going to depend on the shape of the existing bone structure and whether or not a genioplasty was done.  Also, we have no idea where there is still swelling in these pictures

Also, people who have BSSO often have quite short ramii (??) which I think gives more of of a U shape and less definition.  There is no bone in the back to stretch/support the tissue so it ends up in the prejowl area

Many people who need BSSO also need implants or a chin wing to get an "ideal" bone structure

[nrelax11]

The second girl seemed to have an impaction which lead to her having a more U shaped jaw

[Cmonster]

Wow the second girl looks completely different, nose , lips, jawline, and she probably had a genio too...

[MrFox]

Why does the second girl have less scleral show in the after photo?

[MrFox]

It looks like she is just looking up slightly more, but I may be wrong.

To me it looks like the lower lids have been lifted or have more support.

[Optimistic]

I suspect this is primarily the result of poor rami length pre-op. As a result the large degree of rotation flattens the mandibular plane and makes it appear wider, then the advancement brings out the U shape more.

Hypothetically a chin wing can help as it can not only advance but also widen the jaw angles to offset this effect.

Since the only way to create a V-shape would be to make the anterior part of the mandible thinner via bone shaving (asians do this sometimes I believe), or to widen the posterior part (which is what a chin wing can do).  This depends a lot on the already existing facial shape and deficiencies of course.


Edit: Think of it like an optical illusion. If the U-shaped jaw is rotated upwards posteriorly then it will look more v-shaped. Especially as it's recessed so less of the rear is coming through. Then with advancement more of the jaw's shape becomes apparent. Plus you now have more of the jaw widening earlier on in the front of the face due to advancement. If that makes any sense at all. this is not easy to explain. Makes sense in my mind however 

[timang]

Tiny and Disillusioned, where do you get all that info!  That sounds very sensible.

I added the patients' side profile pics too. Perhaps that gives a better impression of their bone structure.

[timang]

Can you do a chin wing in combination with BSSO?

Yes. You can do a chin wing only or a BSSO + chin wing.

Especially, could a chin wing entirely solve this issue?

Entirely is such a strong word that I have to say no.

[timang]

What i meant is:
can a chin wing create sharp mandibular angles and a decent v line?

This patient had a chin wing. See for yourself.

[MrFox]

It looks like his lower lip shape went from straight to curved or pointed in the middle which makes his mouth look smaller and less masculine. I know jaw and chin osteotomies can reduce the amount of vermilion that shows but why would the shape change like that?

[timang]

Certainly a solid improvement, however far from ideal.

Is this the best that can be achieved ?

No, but a result one should expect imho.

[nrelax11]

It looks like he also had a maxillary advancement which changed his top lip. Maybe the chin wing caused his lower lipto kind of roll out.

[Gregor Samsa]

He looks better in the after pictures but it still looks like he needs some kind of jaw surgery.

[Tiny]

What i meant is:
can a chin wing create sharp mandibular angles and a decent v line?

It depends on what you're starting with.  I definitely don't think it can take you from hidden, completely non-definite angles and a short ramus to big chunky modelesque angles - you need implants for that.  It enhances what you have but there are limits

Also it will depend on body fat %