Author Topic: Surgery Case Review (Severe Bimaxillary Protrusion)  (Read 1821 times)

Suchislife

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Surgery Case Review (Severe Bimaxillary Protrusion)
« on: April 11, 2022, 04:19:42 AM »
Hi Forum members,

Over the past 2-3 years I have been thinking about getting orthognathic surgery. I am a 25 y/o male. I've posted here before with my case, but thinking about it still, in more detail as time goes by...

For simplicity I'm going to lay things out in dot points, things to help me look over + my main concerns to date:

1) At this link I provide multiple images to assist the discussion
https://imgur.com/a/PJUincv. They are:
a) My skull
b) A DJS proposal from a consultation I had last year
c) Some overlays I (roughly) made ...
d) Images of similar cases or that had some key takeaway for me (My jaw area looks kind of similar to the image with the Asian fellow)

2) My current situation as I understand it:
Severe bimaxillary protrusion,
good/class 1 bite (i had braces before actually),
very small lower jaws (upper and lower)
I have sleep apnea
I don't want implants

3) Surgical options that have been proposed/that I currently consider appropriate for my case:
a) As per the image, Counter-clockwise rotation, advancement of jaws (upper, ~1cm for lower), mostly retain existing bite, large genioplasty (due to high proclination of lower jaw teeth, the surgeon offered some grafting in the labiomental fold), minimal downgraft/vertical lengthening. (conservative)
b) Same as (a) but with more vertical lengthening such as in the 'similar cases' images. The 2 male similar cases look like they have little forward advancement, but mostly downgrafting + big genioplasty.
c) Same as (a)/(b) but instead undo bimaxillary protrusion via pre-molar extractions, decompensation for large overbite/overjet then full forward and downward advancement. (less conservative, intense ortho)
Note: currently solution (b) seems the best to me



~My Concerns/General Thoughts

4) I have a significant concern with regards to solutions (a)/(b), due to how they retain the proclination of my teeth. I fear that right now since I had severe protrusion, that the protrusion is only masked by my recessed/underdeveloped jaws. If I move the jaws forward, but do not undo the bimaxillary protrusion, will it look like I have highly protrusive teeth post surgery?
Note: In general I have a hard time thinking about the outcome of the surgery, as did my surgical consultant. My case as I understand is not very common, such a small/compact jaw + highly proclined teeth with a near normal/class 1 bite.

5) I like the idea of undoing proclination via orthodontics/decompensation. By creating this 'real' overbite/overjet, the genio can be reduced as more forward movement is achieved by the BSSO. Noting that there is very little room in my dental arch to move the lower teeth back, I believe I will need to extract pre-molars. Thoughts?
I also wonder is it possible to just extract lower pre-molars and pull the teeth back creating a relatively 'normal' bite but with a difference of two teeth between upper and lower jaw...would anyone happen to know if this is ever done or is this just dumb?...
Note: last image with the girl I saw recently was interesting, orthodontically as I understand they seemed to have moved those lower teeth way back...behind the chin, then did a big advancement. The result was quite good.

6) I have a very narrow lower jaw to the tip of my chin. For the genioplasty, if I move the chin forward, that is already narrow (narrower than my proclined lower dental arch...), will it make my chin look overly pointy...or can the genioplasty make the jaw look wider. The genio freaks me out a bit because if I don't undo the proclination, I would likely need a big genio with grafting as I understand (similar to all the similar case images). The geometry is weird to think about, between highly proclined lower teeth at approx 40 degrees + big genio.
 
6) When CCW is done, such as with the surgical consultant I previously met with for the 3D scan, I noticed that through the CCW rotation, by rotating my lower jaw a few degrees more vs the upper jaw, some of the proclination was undone. I noticed this recently looking back at things. This seems somewhat noteworthy...

7) I've seen some cases with great results that seem to retain proclination of lower teeth (as well as upper), in the cases of open bites or similar. You can tell because the roots beneath the incisors push out a lot still, as well as just looking at the after cephlo-side profile. Maybe I over-estimate the need to pull those teeth back. Such as in the case of the older fellow (see image) its interesting to me how his teeth are still highly proclined but you dont notice it at all in the image.

7) Vertical lengthening and gummy smile. I've seen similar cases to mine where ppl have less proclination but similarly small jaws. They can't smile in a way that shows teeth properly. I am similar but can show more teeth due to the proclination pushing the teeth out. I fear that if the proclination is not undone that it will contribute to a gummy smile if the lengthening is done. This is a more minor concern however as right now my upper lip covers about 1/3 of my upper teeth, however I note it regardless.




I've narrated on a bit autistically tbh...because I wanted to make my current feelings as clear as possible...
I thought I had more considerations than this, but thats all for now.


Thank you very much for your time,
D
« Last Edit: April 11, 2022, 04:31:02 AM by Suchislife »

varbrah

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Re: Surgery Case Review (Severe Bimaxillary Protrusion)
« Reply #1 on: April 14, 2022, 10:21:04 AM »
c) Same as (a)/(b) but instead undo bimaxillary protrusion via pre-molar extractions, decompensation for large overbite/overjet then full forward and downward advancement. (less conservative, intense ortho)
Note: currently solution (b) seems the best to me

5) I like the idea of undoing proclination via orthodontics/decompensation. By creating this 'real' overbite/overjet, the genio can be reduced as more forward movement is achieved by the BSSO. Noting that there is very little room in my dental arch to move the lower teeth back, I believe I will need to extract pre-molars. Thoughts?
I also wonder is it possible to just extract lower pre-molars and pull the teeth back creating a relatively 'normal' bite but with a difference of two teeth between upper and lower jaw...would anyone happen to know if this is ever done or is this just dumb?...
Note: last image with the girl I saw recently was interesting, orthodontically as I understand they seemed to have moved those lower teeth way back...behind the chin, then did a big advancement. The result was quite good.

Undoing the bimaxillary protrusion/decompensating is the soundest approach IMO.

Your ANS and maxillary incisors are currently in good balance (aligned along a vertical plane), meaning CCW standalone would make the protrusion of the maxillary component look more severe. Retroclining the maxillary incisors a bit would allow for a some CCW to take place without compromising aesthetics - just enough to get the ANS and incisors back in alignment.

For the lower arch - yes, seems like you'd need to open up space with premolar extractions to get any material decompensation. As you said, this would allow for a larger BSSO which addresses your main problem point (mandible), and you'd need less genio movement.

Btw, is that treatment simulation made by a specific Aussie surgeon ;D? The proposed advancement is way too large IMO - ANS advanced to be in-line with your nasal bridge, lol. Great from an airway perspective, but looks like it would compromise your nasal aesthetics quite a bit. Going off of Arnett/Gunson's TVL, your maxilla is already fairly well-positioned from a soft tissue perspective. Following decomp, maybe a few mm's needed at most and CCW should be able to take care of the rest IMO.

GJ

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Re: Surgery Case Review (Severe Bimaxillary Protrusion)
« Reply #2 on: April 15, 2022, 07:33:50 AM »
The proclination is so severe that it's possible when those teeth are uprighted you'd only need lower jaw surgery due to the overjet created. If that's not enough advancement of the jaw at that point, it's also possible that retroclining those incisors + lower bicuspids would allow for that movement. I'm a big fan of avoiding upper jaw surgery if possible, though. That's where things go wrong aesthetically due to the nose/philtrum area.

Short of that, CCW seems reasonable. I agree with the other commenter that movement seems extreme (i.e. creating an anti-face).

It's hard to be more specific given the records you shared. I'd like to see records of you, not other people who look like you. If you post those here I'll chime in more.

Millimeters are miles on the face.

varbrah

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Re: Surgery Case Review (Severe Bimaxillary Protrusion)
« Reply #3 on: April 15, 2022, 12:13:54 PM »
I'm a big fan of avoiding upper jaw surgery if possible, though. That's where things go wrong aesthetically due to the nose/philtrum area.
Any clue on the typical amount of advancement that most can get away with without causing disharmony between the mobilized and non-mobilized section of the maxilla?

Obviously depends case by case, but from before/afters I've seen, seems like ~3mm or so advancement at ANS avoids creating any big issues.

kavan

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Re: Surgery Case Review (Severe Bimaxillary Protrusion)
« Reply #4 on: April 15, 2022, 06:26:35 PM »
If indeed you have SEVERE bimax protrusion, have you considered the possibility of looking into having an anterior segmental osteotomie (ASO)?

ASO is a surgery commonly done in KOREA but not so common in the US. To the best of my knowledge, having the ASO surgery doesn't preclude the jaws also being advanced.

Here's a basic illustration of what I'm referring to:

https://www.youtube.com/watch?v=ddIXs2eZCaM
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GJ

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Re: Surgery Case Review (Severe Bimaxillary Protrusion)
« Reply #5 on: April 16, 2022, 07:37:16 AM »
Any clue on the typical amount of advancement that most can get away with without causing disharmony between the mobilized and non-mobilized section of the maxilla?

Obviously depends case by case, but from before/afters I've seen, seems like ~3mm or so advancement at ANS avoids creating any big issues.

Yeah 3mm is a good number, but you can probably bump that to under 5mm being relatively safe. But it's not just the advancement. I think the cutting of the alar/muscles/tissue around the nose causes just as many problems. And these are in the center of your face rather than the lower part of the face like a BSSO. So the eye gravitates toward any deleterious result more so.
Millimeters are miles on the face.

Suchislife

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Re: Surgery Case Review (Severe Bimaxillary Protrusion)
« Reply #6 on: April 20, 2022, 12:58:55 AM »
Thanks for the responses guys, to add to the discussion given recent comments:

Btw, is that treatment simulation made by a specific Aussie surgeon ;D? The proposed advancement is way too large IMO - ANS advanced to be in-line with your nasal bridge, lol. Great from an airway perspective, but looks like it would compromise your nasal aesthetics quite a bit. Going off of Arnett/Gunson's TVL, your maxilla is already fairly well-positioned from a soft tissue perspective. Following decomp, maybe a few mm's needed at most and CCW should be able to take care of the rest IMO.

I will limit my response to just say that the choices are pretty limited in AUS, and I will likely be going overseas if I do take action. :-X Regarding surgeons to consult with, I haven't looked much further than some of the bigger names on Youtube, such as Instituto Maxilofacial, Arnett Gunson, Antipov or similar... If any1 has recommendations for surgeons, in Asia in particular (such as Korea) that could be interesting, given that I have this kind of protrusion that is common in those regions...

I will also add that regarding the ANS being in-line etc. the consultant who offered that solution said it would be necessary to cut away (at least partially) the anterior nasal spine given how mine has formed. I have no idea if this is a good or bad idea.


The proclination is so severe that it's possible when those teeth are uprighted you'd only need lower jaw surgery due to the overjet created. If that's not enough advancement of the jaw at that point, it's also possible that retroclining those incisors + lower bicuspids would allow for that movement. I'm a big fan of avoiding upper jaw surgery if possible, though. That's where things go wrong aesthetically due to the nose/philtrum area.

Short of that, CCW seems reasonable. I agree with the other commenter that movement seems extreme (i.e. creating an anti-face).

It's hard to be more specific given the records you shared. I'd like to see records of you, not other people who look like you. If you post those here I'll chime in more.

Fair points, please see the attached link for images. https://imgur.com/a/XIvpNYa

I think it's possible that I might only need lower jaw surgery if the proclination is undone as you suggest, however, since my upper and lower jaw teeth mesh together to a near class 1 bite, I believe as the lower jaw moves forward the upper will at least need to be widened for the geometry to work (SARME/SARPE or similar). I will also note that my upper jaw, although looks reasonably well-formed from the side profile 3D image of my skull, the arch towards the molars is quite narrow. It is as if my jaw refused to grow wider at some stage of my childhood, upper and lower, but to fit all teeth, my tongue then proclined out the incisors and bicuspids. Upper jaw is narrow, then lower jaw is narrow and has heavily proclined teeth...

I also add some images of me smiling/grinning to show that actually at least when I see myself from the side view, my upper incisors don't come out that far, and appear to be able to be pushed out further without overly impacting the aesthetics...maybe...

I will also note that I have some asymmetry when I speak/rest my face, however, I don't know how much is soft tissue/bone. The surgical consultant also commented on this.

If indeed you have SEVERE bimax protrusion, have you considered the possibility of looking into having an anterior segmental osteotomie (ASO)?

I have read a bit about ASO however off the cuff to be honest it freaks me out a bit. I have more researched into pre-molar extraction and at this moment would rather do that over a longer period of orthodontics I think.

I will need to look into it further.



More generally I will note to all that I believe it is/will be more common for surgeons to suggest not doing the intensive ortho to remove the proclination as it is 'easier', and may even mean that I wouldn't even get orthodontics for my case (again similar to some of the cases in the original link). From the consults I have gotten locally, this is the approach they leaned towards, and they flat out could not support the other approach as it was something they were not experienced/comfortable with/did not know of an orthodontist which would partner with them for such an approach.


Thanks again,
D

kavan

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Re: Surgery Case Review (Severe Bimaxillary Protrusion)
« Reply #7 on: April 20, 2022, 06:40:05 PM »
Thanks for the responses guys, to add to the discussion given recent comments:


I have read a bit about ASO however off the cuff to be honest it freaks me out a bit. I have more researched into pre-molar extraction and at this moment would rather do that over a longer period of orthodontics I think.

I will need to look into it further.



More generally I will note to all that I believe it is/will be more common for surgeons to suggest not doing the intensive ortho to remove the proclination as it is 'easier', and may even mean that I wouldn't even get orthodontics for my case (again similar to some of the cases in the original link). From the consults I have gotten locally, this is the approach they leaned towards, and they flat out could not support the other approach as it was something they were not experienced/comfortable with/did not know of an orthodontist which would partner with them for such an approach.


Thanks again,
D

ASO removes the first pre-molars along with some of the alveolar bone holding the those teeth it also removes a bridge of bone from the upper palate (roof of mouth, part of maxilla) connecting the pre-molars. So, it's a somewhat 'partial' Lefort 1 that moves the upper front teeth as in the canines, lateral incisors and central incisors backwards to address the protrusion they have. The similar type of surgery that addresses a push back of the lower front teeth I think is called Subapical oestotomy. The bite as it pertains to the molars meshing does not change. The native INCLINATION of the front and lower teeth (some outward inclination gives good lip support!) does not change when the complex moved by this type of surgery is pushed backwards. It directly addresses the protrusion.

When the excess protrusion is addressed this way, recession at the jaws can be evaluated in the absence of excess protusion that could stand to LIMIT bringing both jaws forward if the jaws were advanced WITH the pre-existing protrusion.

However, because (I think you are in Australia), you might need to double check if you have a legit diagnosis of 'severe' bimax protrusion and double check with a Korean doctor (in Korea). I say this because your photos you recently showed don't look like hard core bimax protrusion to me. Looks more like DEEP BITE/ 'short chin' because your front upper teeth look vertically oriented whereas the bimax protrusion (legit hard core cases) have a much more outwardly diagonal orientation to them which I don't see in your recent photos.

As to cutting down (some of) the ANS, that's something they do when the maxilla can be brought forward more BUT the ANS (if not cut down) would make the maxillary advancement look UN aesthetic.

From your recent photos, it's kind of looking like it could be possible to limit the pre-molar extractions to your lower pre-molars to create a large overjet for a larger lower jaw advancement. Might even be possible to 'buck out' your front incisors more to increase overjet for lower jaw advancement.

 As to the ASO, it's likely your not a dead ringer for it. It was your assessment of 'severe' bimax protrusion that elicited the suggestion from me to look into it. It's hard to pin point exactly what to do. But most certainly DON'T limit assessments to only in Australia.

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