Will ortho+bimax or ortho alone achieve the best aesthetic result?

[simonsjaw11]

Hi guys, ten years ago I had braces to fix my mouth protrusion problem, but after that I was told the protrusion is both dental and skeletal, and was recommended to do a jaw surgery to set my maxilla back. I made consultations with two surgeons but one said the problem is really just dental and another suggests that a 3mm backward movement will archive the best result.

I've attached the two cephs they took (not sure if the conflicting judgements are caused by the different resolution or angles etc?).
https://imgur.com/a/XtzXC3v

Plan A: maxilla set back to 3mm, mandible downward 3mm, and a 5mm genio.

Plan B: ortho alone + genio. The ortho could help me to get a concave lip curve. But when I ask how to move my subnasal point backward, the surgeon said there might be ways to move the bones underneath the nose backward, but not the jaw bone?

How do you guys judge the AP position of my maxilla and these plans? The problem might be slight but I really hope to achieve the best aesthetic outcome even if it's small movements for surgery. Please any advice or discussion will be of great help. Many thanks!

[kavan]

Mouth protrusion is usually BIMAX protrusion. You have that. It is addressed by isolated or segmented osteotomies where these osteotomies are to the ALVEOLAR process which is the TEETH BEARING aspect of the bone. They don't require a Lefort 1 or a BSSO to do them. The osteotomies isolated to the alveolar process are called 'SUB-APICAL' which mean enough away from the root of the tooth. But not to the area where they would do a Lefort 1.

How they perform that type of osteotomy is like this: The premolars are EXTRACTED. A subapical SEGMENT within the alveolar process and in front of the extraction space (toward the lips) is cut so it can be SELECTIVELY moved BACKWARDS into the space left by the extraction gap.
2 premolars per jaw (1 from each side) are extracted for the surgery. In THAT way, the lip protrusion is SET backwards

These type of subapical isolated or segmented osteotomies to the alveolar process can specifically address the lip protrusion where that ALONE would address it in the ABSENCE of a Lefort 1 and/or a BSSO which looks to be your case. Of course, they can be done along with a genio too.

Plan A 'sounds like' it could involve a Lefort 1 to set WHOLE maxilla back which does not sound like a plan for the type of oestotomies I'm talking about above.

Plan B 'sounds' like it could be more in the venue of the isolated osteotomies I'm talking about above given the ortho said there 'might be ways to move the bones underneath the nose backward but not the jaw bone'. The WAY to do that is what I mentioned above. However the phrase; 'ortho ALONE' is baffling to me because the way to move the bones underneath the nose but not the base of the nose (as in a Lefort 1) is via the isolated segmented sub apical osteotomy to alveolar process and that is SURGERY, not 'ortho alone'

That said, now that I've elaborated on WHAT TYPE of surgery specifically addresses BIMAX PROTRUSION (mouth protrusion), go back and INQUIRE if Plan B involves isolated segmented subapical osteotomies to the alveolar process in the ABSENCE of a Lefort 1 and/or a BSSO.

ETA: Illustration included with this post.

[kavan]

To my prior post with the illustration, observe that the isolated osteotomy for the bimax protrusion:

a: does not move the base of the nose backwards as would be the case with a Lefort 1. So the nose does not lose it's support. It only moves the PROTRUSIVE segment of the alveolar maxilla backward.

b: It makes the chin recession look LESS or demonstrates that what looks like chin recession is due to the lips protruding too much (bimax protrusion). In the illustration, I did NOT alter the chin.

The illustration is not meant to be predictive of your results/outcome. It is meant to demonstrate the CONCEPT behind addressing bimax protrusion via the type of osteotomies discussed in the prior post.

[simonsjaw11]

Mouth protrusion is usually BIMAX protrusion. You have that. It is addressed by isolated or segmented osteotomies where these osteotomies are to the ALVEOLAR process which is the TEETH BEARING aspect of the bone. They don't require a Lefort 1 or a BSSO to do them. The osteotomies isolated to the alveolar process are called 'SUB-APICAL' which mean enough away from the root of the tooth. But not to the area where they would do a Lefort 1.

How they perform that type of osteotomy is like this: The premolars are EXTRACTED. A subapical SEGMENT within the alveolar process and in front of the extraction space (toward the lips) is cut so it can be SELECTIVELY moved BACKWARDS into the space left by the extraction gap.
2 premolars per jaw (1 from each side) are extracted for the surgery. In THAT way, the lip protrusion is SET backwards

These type of subapical isolated or segmented osteotomies to the alveolar process can specifically address the lip protrusion where that ALONE would address it in the ABSENCE of a Lefort 1 and/or a BSSO which looks to be your case. Of course, they can be done along with a genio too.

Plan A 'sounds like' it could involve a Lefort 1 to set WHOLE maxilla back which does not sound like a plan for the type of oestotomies I'm talking about above.

Plan B 'sounds' like it could be more in the venue of the isolated osteotomies I'm talking about above given the ortho said there 'might be ways to move the bones underneath the nose backward but not the jaw bone'. The WAY to do that is what I mentioned above. However the phrase; 'ortho ALONE' is baffling to me because the way to move the bones underneath the nose but not the base of the nose (as in a Lefort 1) is via the isolated segmented sub apical osteotomy to alveolar process and that is SURGERY, not 'ortho alone'

That said, now that I've elaborated on WHAT TYPE of surgery specifically addresses BIMAX PROTRUSION (mouth protrusion), go back and INQUIRE if Plan B involves isolated segmented subapical osteotomies to the alveolar process in the ABSENCE of a Lefort 1 and/or a BSSO.

ETA: Illustration included with this post.

Thank you so much, Kavan! The morph you made looks perfect! That's really what I want to look like after the surgery. I did asked Gunson about "move the bone underneath the nose backward" and he said it could be ALVOELAR or ANS but it's not his expertise so he didn't elaborate, and he suggested me to get the dental protrusion fixed FIRST, and then see how to handle the bone. Is that because the teeth moving backward may also lead the alveolar process backward a little bit? (I also have a lot of space between my upper teeth)...

Also, given the direction is to set back the bone, why is 3-pieces lefort I not recommended? If the whole bone moves backward, would that also address the mouth protrusion problem but also move the subnasal point backward without extracting my teeth? I think it may look nicer if my subnasal vertical line can be closer to my nasion vertical line...

[kavan]

Thank you so much, Kavan! The morph you made looks perfect! That's really what I want to look like after the surgery. I did asked Gunson about "move the bone underneath the nose backward" and he said it could be ALVOELAR or ANS but it's not his expertise so he didn't elaborate, and he suggested me to get the dental protrusion fixed FIRST, and then see how to handle the bone. Is that because the teeth moving backward may also lead the alveolar process backward a little bit? (I also have a lot of space between my upper teeth)...

Also, given the direction is to set back the bone, why is 3-pieces lefort I not recommended? If the whole bone moves backward, would that also address the mouth protrusion problem but also move the subnasal point backward without extracting my teeth? I think it may look nicer if my subnasal vertical line can be closer to my nasion vertical line...

Well, after the premolars are removed, one could do a limited lefort 1 that would move an anterior segment back. But ANS support to nose would be lost and the nose would rotate down. So, why would you want that?

What you got from Gunson was that he doesn't do the type of surgery I was talking about and you can get the bimax protrusion elsewhere done first.

I can't opine on why a 3 piece lefort was not recommended other than to say I didn't recommend it. So, you are asking me about something I didn't suggest.

What I will say is that if you LIKE the morph, it ILLUSTRATES my suggestion and it would behoove you to consult around about the procedure I suggested. If there are 'what abouts' OTHER suggestions, than the other person who suggests those can elaborate on them.

ETA:  If you think your subnasal vertical line can be closer to your nasion vertical line, then that's something that's possible AFTER you do the bimax protrusion procedure as Gunson suggested (get protrusion fixed FIRST). In effect Gunson suggested the same thing I did; get protrusion addressed FIRST. Later you can entertain other surgical suggestions involving Leforts and BSSOs.

[GJ]

I'm not familiar with the procedure Kavan mentioned, but I'd say if you do go that route and extract teeth, read up on that first, and make sure to extract second premolars, which have a lot less root structure and thus less bone loss.

When you say "set the maxilla backward 3mm" is that pure linear movement or CCW? If CCW I can see how it would help.

[kavan]

I'm not familiar with the procedure Kavan mentioned, but I'd say if you do go that route and extract teeth, read up on that first, and make sure to extract second premolars, which have a lot less root structure and thus less bone loss.

When you say "set the maxilla backward 3mm" is that pure linear movement or CCW? If CCW I can see how it would help.

Well, the surgery technique of that procedure is to remove the pre-molars closer to ANTERIOR which is the first pre-molar. It's called anterior segmental osteotomy. 'Bone loss' is an inherent part of the procedure because it removes a tract of bone (alveolar) along with the pre-molars that's responsible for kicking up the bimax protrusion. So, bone loss here is a non issue because it goes along with the territory just like bone loss is part of an impaction procedure.  Here's illustration of it.

ETA: It's the protrusion that is ANTERIOR to first pre-molar that is the problem which is why the first pre-molar is sacrificed and not the second pre-molar.

[simonsjaw11]

I'm not familiar with the procedure Kavan mentioned, but I'd say if you do go that route and extract teeth, read up on that first, and make sure to extract second premolars, which have a lot less root structure and thus less bone loss.

When you say "set the maxilla backward 3mm" is that pure linear movement or CCW? If CCW I can see how it would help.

Hi GJ, thanks for the input. Yes my major concern is the teeth extraction, and since it's not a common surgery there are few papers talking about its complication...

3mm is linear movement, Wolford said my occlusal plane is normal so doesn't need any rotation...he did say it can be up to 5mm if I want, but I'm not sure how much movement would achieve the best aesthetic result.