Orthodontics in lieu of surgical maxilla impaction

[wigglewiggle]

My orthodontist recently suggested using a miniscrews plus lingual braces system to achieve maxilla impaction and ccw rotation without upper jaw surgery.

Here is a paper by the orthodontist who invented the system:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4053581/

Here is a business wire article on the system:
https://www.businesswire.com/news/home/20160801005583/en/Central-Orthodontic-Clinic-Revolution-Orthodontics-Accomplished-KILBON

Here are some before and afters
http://kilbon.com/H-default01/change/befor-after.php

My ortho is confident that the orthodontic result can approximate the surgical result without going through the full ordeal, which sounds like a very attractive plan. If I hopped on board with this treatment, instead of double jaw surgery (you can find Gunson's surgical plan for me in my post history if interested) I'd be able to get away with just ortho (maxilla impaction) +single jaw surgery (mandible advancement).

The thing is the system is so new that I can't seem to find any patient review on the process or the final result. What do y'all think of this technology?

[kavan]

Sounds like a mechanically efficient system to correct dento-alveolar protrusion and over extrusion of upper front teeth. System that intrudes and retracts upper jaw front teeth, maybe extrudes upper jaw back teeth...intrusion, extrusion, retraction, protraction of teeth, an ORTHO DEVICE that's more efficient than other ortho devices.

'Impaction' is when they cut a wedge of bone from the anterior maxilla...excess gum show, vertical maxillary excess. 'Intrusion' is basically when they shove LONG TEETH up into the jaw bone.

It depends. If for example, your front upper teeth are too long and too protrusive and other teeth could be moved by a combo of intrusion, extrusion, protraction and retraction as to offset unwanted; extrusion, intrusion, retraction and protraction respectively and this type of ortho ALONE would correct the hyperdivergence, than it would be a better and more efficient system than braces simply because it lets individually specific forces to be exerted on a number of different teeth, in turn giving some CCW-r to correct hyperdivergence.

So it would depend on if YOU wanted to correct hyperdivergence by this way along with a BSSO or if you wanted the type of advancement Gunson provides.

You left no link to your Gunson proposal, so I'm not going to ferret that out. Just to say that people go to Gunson when they want the type of aesthetic he gives. So, no idea if this would give same outcome or otherwise be 'equal' to a Gunson surgery. That's something your ortho would have to predict and/or explain to you.

[kavan]

ETA: The mini screws most likely would be for TADs.

[wigglewiggle]

Sounds like a mechanically efficient system to correct dento-alveolar protrusion and over extrusion of upper front teeth. System that intrudes and retracts upper jaw front teeth, maybe extrudes upper jaw back teeth...intrusion, extrusion, retraction, protraction of teeth, an ORTHO DEVICE that's more efficient than other ortho devices.

'Impaction' is when they cut a wedge of bone from the anterior maxilla...excess gum show, vertical maxillary excess. 'Intrusion' is basically when they shove LONG TEETH up into the jaw bone.

It depends. If for example, your front upper teeth are too long and too protrusive and other teeth could be moved by a combo of intrusion, extrusion, protraction and retraction as to offset unwanted; extrusion, intrusion, retraction and protraction respectively and this type of ortho ALONE would correct the hyperdivergence, than it would be a better and more efficient system than braces simply because it lets individually specific forces to be exerted on a number of different teeth, in turn giving some CCW-r to correct hyperdivergence.

So it would depend on if YOU wanted to correct hyperdivergence by this way along with a BSSO or if you wanted the type of advancement Gunson provides.

You left no link to your Gunson proposal, so I'm not going to ferret that out. Just to say that people go to Gunson when they want the type of aesthetic he gives. So, no idea if this would give same outcome or otherwise be 'equal' to a Gunson surgery. That's something your ortho would have to predict and/or explain to you.

Sounds like a mechanically efficient system to correct dento-alveolar protrusion and over extrusion of upper front teeth. System that intrudes and retracts upper jaw front teeth, maybe extrudes upper jaw back teeth...intrusion, extrusion, retraction, protraction of teeth, an ORTHO DEVICE that's more efficient than other ortho devices.

'Impaction' is when they cut a wedge of bone from the anterior maxilla...excess gum show, vertical maxillary excess. 'Intrusion' is basically when they shove LONG TEETH up into the jaw bone.

It depends. If for example, your front upper teeth are too long and too protrusive and other teeth could be moved by a combo of intrusion, extrusion, protraction and retraction as to offset unwanted; extrusion, intrusion, retraction and protraction respectively and this type of ortho ALONE would correct the hyperdivergence, than it would be a better and more efficient system than braces simply because it lets individually specific forces to be exerted on a number of different teeth, in turn giving some CCW-r to correct hyperdivergence.

So it would depend on if YOU wanted to correct hyperdivergence by this way along with a BSSO or if you wanted the type of advancement Gunson provides.

You left no link to your Gunson proposal, so I'm not going to ferret that out. Just to say that people go to Gunson when they want the type of aesthetic he gives. So, no idea if this would give same outcome or otherwise be 'equal' to a Gunson surgery. That's something your ortho would have to predict and/or explain to you.

Appreciate the response, Kavan.

I don't have particularly long teeth, but I do have protrusive upper (and lower) front teeth. According to my ortho, as upper teeth are intruded, sometimes the gum would follow the intrusion and move up, leaving roughly the same amount of teeth exposed. In case the gum did not "intrude" to an equal extent as the teeth, my ortho would do some gingivectomy to make sure my front teeth are exhibited at an aesthetically satisfactory degree. Does this sound plausible/right to you?

Now back to the question of to what extent this orthodontic + bsso result could approximate Gunson's plan (which is in the attachments if you're interested), my understanding is that ccw rotation and intrusion of front upper teeth would help visually decrease the vertical excessiveness in my maxilla, and my lower jaw would follow the rotation and come out to a slight degree. This effect to me sounds similar to the that of G's surgical plan, except that orthodontics alone wouldn't involve no bone grafting to lengthen my posterior maxilla. I am not sure what the implication is.

Lastly - Is there any other surgical movement that can't be mimic by this ortho movement or any caveats that I'm missing here?

[kavan]

Well, ya, sometimes the gum follows and if not a gingivectomy would need to be done.

By the way, I did managed to find your proposed displacements numbers/movements on some thread. They said the Gunson proposal was to impact approx 5mm?. and push maxilla backwards somewhat, posterior downgraft (by forgot how much) and BSSO would advance about a 10mm. I don't see the ortho device doing all that to that extent, especially the advancement at the pogonian that one gets with the BSSO. so you have to grill your ortho if it will achieve THOSE mm displacements.

The ortho proposed does have a CCW-r effect. But I doubt it will be 'equal' to the G proposal.

Again, show your ortho the NUMBERS (mm displacements) that go with the visual and grill as to if the device will get same similar.

[Post bimax]

In my opinion there is NO WAY you will achieve a result even close to that displacement diagram via orthodontics alone, intrusion or no.

Also, I don't understand why Gunson would go through the trouble of a genioplasty to still give a chin that is a bit weak.  Maybe he's really concerned about lip seal.

[kavan]

In my opinion there is NO WAY you will achieve a result even close to that displacement diagram via orthodontics alone, intrusion or no.

Also, I don't understand why Gunson would go through the trouble of a genioplasty to still give a chin that is a bit weak.  Maybe he's really concerned about lip seal.

Why? Because when the SLIDING genio is relied on just to get the horizontal advancement vector from it, the vertically upward vector from it can give an unwanted 'step off' and/or an unwanted overly acute lip to chin fold (groove). There is also an unwanted vertically downward vector to a person starting out with a high MPA such as the OP. Most of it is offset by the CCW-r at the maxilla and subsequent BSSO. The rest offset by the added CCW-r 'look'/effect of the genio. So, you wouldn't want to use a diagonally downward and outward genio to get the horizontally outward vector either. Hence there can be 2 'unwanted' vertical displacement vectors, one being too much UP and the other, too much DOWN with EITHER the sliding genio or the down and outward genio in this case. Basically, 'maximize THIS but minimize THAT' is the concept of OPTIMIZATION.

The general goal of the CCW-r relative to Gunson is to maximize the BSSO advancement via the rotation of the maxilla, in which case, the chin moves along with that which allows for minimizing dependence on isolated chin advancement. The SLIDING genio is used to give more of a CCW-r 'look' or effect. But there is a limit to how much you can use it to advance the chin with it. Keeping in mind that a sliding genio is along a diagonal 'cut plane', it has 2 directional displacement vectors: horizontally outward and vertically upward. The 'WANTED' horizontal displacement vector needs to be LIMITED by the 'UNWANTED' vertically upward displacement vector that would go along with it. Because what's unwanted and to be avoided is that the OVERLY ACUTE lip to chin GROOVE. Also, in a person suffering a high MPA and/or just needing the CCW-r effect, you can't really give them the diagonally downward genio for more advancement because a vertically downward vector is ALSO unwanted in such a case.

[Post bimax]

Why? Because when the SLIDING genio is relied on just to get the horizontal advancement vector from it, the vertically upward vector from it can give an unwanted 'step off' and/or an unwanted overly acute lip to chin fold (groove). There is also an unwanted vertically downward vector to a person starting out with a high MPA such as the OP. Most of it is offset by the CCW-r at the maxilla and subsequent BSSO. The rest offset by the added CCW-r 'look'/effect of the genio. So, you wouldn't want to use a diagonally downward and outward genio to get the horizontally outward vector either. Hence there can be 2 'unwanted' vertical displacement vectors, one being too much UP and the other, too much DOWN with EITHER the sliding genio or the down and outward genio in this case. Basically, 'maximize THIS but minimize THAT' is the concept of OPTIMIZATION.

The general goal of the CCW-r relative to Gunson is to maximize the BSSO advancement via the rotation of the maxilla, in which case, the chin moves along with that which allows for minimizing dependence on isolated chin advancement. The SLIDING genio is used to give more of a CCW-r 'look' or effect. But there is a limit to how much you can use it to advance the chin with it. Keeping in mind that a sliding genio is along a diagonal 'cut plane', it has 2 directional displacement vectors: horizontally outward and vertically upward. The 'WANTED' horizontal displacement vector needs to be LIMITED by the 'UNWANTED' vertically upward displacement vector that would go along with it. Because what's unwanted and to be avoided is that the OVERLY ACUTE lip to chin GROOVE. Also, in a person suffering a high MPA and/or just needing the CCW-r effect, you can't really give them the diagonally downward genio for more advancement because a vertically downward vector is ALSO unwanted in such a case.

Is it not possible to add a purely horizontal component with a buttress?  I feel as though the tradeoff of a deeper fold or larger step-off is worth it to get the pogonion to the TVL. 

Otherwise the implication is that there is just no way for him to get an optimal chin position without adding implants down the line.

[kavan]

Is it not possible to add a purely horizontal component with a buttress?  I feel as though the tradeoff of a deeper fold or larger step-off is worth it to get the pogonion to the TVL. 

Otherwise the implication is that there is just no way for him to get an optimal chin position without adding implants down the line.

Then you get something that looks like a ledge sticking out. The chin is close enough to the TVL. If you mean a pure vertical cut so they can advance a section purely horizontally, I don't think they do that or if its' possible.

[Post bimax]

Then you get something that looks like a ledge sticking out. The chin is close enough to the TVL. If you mean a pure vertical cut so they can advance a section purely horizontally, I don't think they do that or if its' possible.

Hmm okay, I can see why the buttress would cause a 'shelf' type look.

Maybe another option is to make the angle of the osteotomy more horizontal so that he can get more MMs of the horizontal component before the mentolabial angle becomes unacceptably acute.  However, I'm not sure how much leeway the surgeon has with that as the cut will be further back on the mandible.

Anyway, if OP likes this overall aesthetic (achieved by whatever orthodontics or otherwise) then there's nothing wrong with that.  It is certainly a large improvement over the starting position.

[kavan]

Hmm okay, I can see why the buttress would cause a 'shelf' type look.

Maybe another option is to make the angle of the osteotomy more horizontal so that he can get more MMs of the horizontal component before the mentolabial angle becomes unacceptably acute.  However, I'm not sure how much leeway the surgeon has with that as the cut will be further back on the mandible.

Anyway, if OP likes this overall aesthetic (achieved by whatever orthodontics or otherwise) then there's nothing wrong with that.  It is certainly a large improvement over the starting position.

The cut is inclined less than 20 deg from the horizont. So advancement over that plane will give more horizontal displacement than vertical. His AP +3.3 and vertical + .8.  You would only get a small segment of chin if you tried to cut vertically to advance out horizontally or purely horizontally to get. The cut is inclined less than 20 deg from the horizont. So advancement over that plane will give more horizontal displacement than vertical. His AP +3.3 and vertical + .8.  You would only get a small segment of chin if you tried to cut vertically to advance out horizontally or purely horizontally to get. I don't feel like drafting out a diagram to show this. It should be self explanatory if you try to cut either a 'pure' vertical or 'pure' horizont through his chin to advance only horizontally. You'll only get a small segment or you will lose the CCW 'look' to the chin which the sliding genio gives.

[kavan]

By the way. Here are the displacement distances of the Gunson proposal. I'm entering where I found them so I DON'T have to rely on memory or ferret something out again that wasn't l linked to in the initial post.




http://jawsurgeryforums.com/index.php/topic,7294.msg69187.html#msg69187  Reply #24

[Post bimax]

The cut is inclined less than 20 deg from the horizont. So advancement over that plane will give more horizontal displacement than vertical. His AP +3.3 and vertical + .8.  You would only get a small segment of chin if you tried to cut vertically to advance out horizontally or purely horizontally to get. The cut is inclined less than 20 deg from the horizont. So advancement over that plane will give more horizontal displacement than vertical. His AP +3.3 and vertical + .8.  You would only get a small segment of chin if you tried to cut vertically to advance out horizontally or purely horizontally to get. I don't feel like drafting out a diagram to show this. It should be self explanatory if you try to cut either a 'pure' vertical or 'pure' horizont through his chin to advance only horizontally. You'll only get a small segment or you will lose the CCW 'look' to the chin which the sliding genio gives.

I was thinking something like this for the cut (blue line):

https://imgur.com/a/YrJoBAl

I didn't check the angles so I don't know what difference it would actually make.  Conceptually I would expect that he could ultimately still get the same overall CCW effect via the vertical displacement, but that he could get more horizontal movement with a lower (non-zero) cut angle.

E.g, 6mm A-P and +.8 vertical

[kavan]

I was thinking something like this for the cut (blue line):

https://imgur.com/a/YrJoBAl

I didn't check the angles so I don't know what difference it would actually make.  Conceptually I would expect that he could ultimately still get the same overall CCW effect via the vertical displacement, but that he could get more horizontal movement with a lower (non-zero) cut angle.

E.g, 6mm A-P and +.8 vertical

Maybe. but there is going to be loss of the CCW look, the more horizontal you go.  They can't get everything perfect on target with all start points. But if you wanted to request a different angle for cut, the person would have to demonstrate to him why in terms of angle inclination displacements. No idea though if the cut plane is chosen to avoid some 'no no' zone which would have to do with the nerves there.

[wigglewiggle]

Hmm okay, I can see why the buttress would cause a 'shelf' type look.

Maybe another option is to make the angle of the osteotomy more horizontal so that he can get more MMs of the horizontal component before the mentolabial angle becomes unacceptably acute.  However, I'm not sure how much leeway the surgeon has with that as the cut will be further back on the mandible.

Anyway, if OP likes this overall aesthetic (achieved by whatever orthodontics or otherwise) then there's nothing wrong with that.  It is certainly a large improvement over the starting position.

I'm female which is why G proposed the tiny/softer chin projection. He also said that the genioplasty would help achieve overall lower jaw advancement without even more BSSO advancement.