Author Topic: Recessed Jaws, What do you think?  (Read 3443 times)

Dogmatix

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Re: Recessed Jaws, What do you think?
« Reply #15 on: September 23, 2019, 10:41:37 PM »
It might be a standard procedure. BUT it's one that depends on finding the EXACT 'Po' point and I'm not too sure you found it. I'm not too sure because it's perfectly normal for someone to have their S-N line 7 degrees away from a pure horizont and his was so.

You rotated his ceph about 7 degrees down. His S-N line was 7 degrees away from a pure horizont which is NORMAL. Your rotation made his S-N line a pure horizont. The cephalostat in the ceph also got rotated 7 deg away from the true vertical. It's perfectly normal for someone to have what is referred to as a 'horizontal' plane eg. S-N or Frankfort horizontal, NOT to have a pure horizont.

Also, he ALREADY HAD a pure horizont that could be drawn from the 'Or' point to a point that could have been the Po point (blue dot) for the Frankfurt horizont. You used a point BELOW that, which happened to be about 7 degrees away from his Or point, found his 'Or' point wasn't horizontal with it and then rotated his ceph 7 degrees  downward in CW.
So, what makes you so sure you found the correct Po point associated with the Frankfurt horizont? It's a hard point to find on a ceph. Although I'm not so sure mine is the exact Po point either, I know it's in that vicinity but is hard to find. In fact it's difficult enough to find in a ceph that Steiner came up with his method of using the S-N line INSTEAD which is easy to spot. So I wouldn't be rotating anyone's ceph unless I was damned well sure I found the EXACT Po point.

Ok, so yes you're correct. There is insecurity in finding po point, I did my best attempt with good intentions and think my guess would still be same.

If anyone read my posts as a recommendation for bimax and ccw, that is not what I'm trying to say. I never ever recommend surgery to anyone, I can just participate in a discussion about what it involves. The thread specifically asks about considering bimax, and I give my take where getting into this may end up. If anyone want a real evaluation and plan, that's not something a forum like this can provide, e.g because of the discussion above. You need real tools,  software and a surgeon for that. I personally think that a consultation for a full bimax may end up with a rotation ccw, but it may also not.

Kavan. I think we clearly have different opinions if it's sensible trying to orientate a ceph. To me, a ceph comes scrambled out of the machine and makes no sense to look at with regard to rotation unless an attempt to orientate it has been made. Looking at something random and you can't say anything, while looking at something where you have an idea what's going on and can motivate and understand the orientation, then you have something to work from. To me, your green line can be just as deceptive as you work with the ceph without any clear attempt to standardize the rotation first. If anything, I guess we can agree that determining the po point is crucial for a better guess.

Just to give an example with my own beautiful skull.
This is what the cephalostat gives
http://imgur.com/tzryPNm

This is after cephx handles it.
http://imgur.com/3aLoLEA

And 2 surgeons use the same orientation as cephx independently as well.
So the ugly duck is the raw ceph.

kavan

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Re: Recessed Jaws, What do you think?
« Reply #16 on: September 23, 2019, 11:22:24 PM »
Ok, so yes you're correct. There is insecurity in finding po point, I did my best attempt with good intentions and think my guess would still be same.

If anyone read my posts as a recommendation for bimax and ccw, that is not what I'm trying to say. I never ever recommend surgery to anyone, I can just participate in a discussion about what it involves. The thread specifically asks about considering bimax, and I give my take where getting into this may end up. If anyone want a real evaluation and plan, that's not something a forum like this can provide, e.g because of the discussion above. You need real tools,  software and a surgeon for that. I personally think that a consultation for a full bimax may end up with a rotation ccw, but it may also not.

Kavan. I think we clearly have different opinions if it's sensible trying to orientate a ceph. To me, a ceph comes scrambled out of the machine and makes no sense to look at with regard to rotation unless an attempt to orientate it has been made. Looking at something random and you can't say anything, while looking at something where you have an idea what's going on and can motivate and understand the orientation, then you have something to work from. To me, your green line can be just as deceptive as you work with the ceph without any clear attempt to standardize the rotation first. If anything, I guess we can agree that determining the po point is crucial for a better guess.

Just to give an example with my own beautiful skull.
This is what the cephalostat gives
http://imgur.com/tzryPNm

This is after cephx handles it.
http://imgur.com/3aLoLEA

And 2 surgeons use the same orientation as cephx independently as well.
So the ugly duck is the raw ceph.

I hear what you're saying. CephX and some doctors rotate it. But still, if that's to be done with reference to FH, the Po point has to be located. Even then the FH isn't a pure horizont in some people. There are deviations.

I'm unclear on the 2 surgeons using same orientation as cephx. I thought Gunson could just define a horizont where he wanted it relative to the vertical he wanted. That is to say choosing the TV where he wanted and just constructing a horizont 90 degrees to it. Does Gunson use cephX? Your head does look somewhat tipped upward in the un tilted ceph though. Some docs want the ceph so that the person is looking horizontally straight ahead into a distant mirror that is eye level.

 Maybe he needs spine surgery.
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kavan

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Re: Recessed Jaws, What do you think?
« Reply #17 on: September 23, 2019, 11:42:12 PM »
In yours, they rotated it 7 degrees. But how much to rotate IF any, would differ from person to person.
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april

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Re: Recessed Jaws, What do you think?
« Reply #18 on: September 23, 2019, 11:52:37 PM »
It looks like some use actual porion, and some also use the top of the ear-rod as porion. Both will give different results I guess.

My tracing/plan from Gunson was re-orientated to FH.

I also saw another surgeon who did his own in house xray on me and was a perfectionist about my head position in the xray machine (he had rejected the xray I brought with me ). But despite controlling my head position in the xray machine, he still later massively re-orientated the xray to FH and drew the TVL based on where it would be if rotated at FH orientation. https://imgur.com/a/fpRIAyQ
« Last Edit: September 24, 2019, 12:20:54 AM by april »

kavan

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Re: Recessed Jaws, What do you think?
« Reply #19 on: September 24, 2019, 12:16:49 AM »
It looks like some use actual porion, and some also use the top of the ear-rod as porion. Both will give different results I guess.

My tracing/plan from Gunson was re-orientated to FH.

I also saw another surgeon who did his own in house xray on me and was a perfectionist about my head position in the xray machine (he had rejected the xray I brought with me ). But despite controlling my head position in the xray machine, he still later massively re-orientated the xray to FH and drew the TVL based on where it would be if at FH orientation. https://imgur.com/a/fpRIAyQ

With reference to the ceph stat being a true vertical, the horizontal he drew as FH is not 'true' horizont. But then again FH does not always mean people have true horizont. The vertical he drew is perpendicular to the FH line he connected though. Basically, they want 'horizont' and the 'vertical' to be perpendicular even when neither are a 'true' horizont or vertical.
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april

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Re: Recessed Jaws, What do you think?
« Reply #20 on: September 24, 2019, 12:37:56 AM »
Looks like I exaggerated when I said massively rotated lol. It's only 3-4 degrees.

This surgeon ended up using the same Dolphin 2d planning software/analysis as Gunson.  So basically (well at least with 2d cephs ) they seem to orientate to FH, and then pop the TVL perpendicular to it and through 'subnasale'.


Dogmatix

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Re: Recessed Jaws, What do you think?
« Reply #21 on: September 24, 2019, 12:48:10 AM »
I hear what you're saying. CephX and some doctors rotate it. But still, if that's to be done with reference to FH, the Po point has to be located. Even then the FH isn't a pure horizont in some people. There are deviations.

I'm unclear on the 2 surgeons using same orientation as cephx. I thought Gunson could just define a horizont where he wanted it relative to the vertical he wanted. That is to say choosing the TV where he wanted and just constructing a horizont 90 degrees to it. Does Gunson use cephX? Your head does look somewhat tipped upward in the un tilted ceph though. Some docs want the ceph so that the person is looking horizontally straight ahead into a distant mirror that is eye level.

 Maybe he needs spine surgery.

I actually haven't compared it exactly and meassured the degree of rotation with e.g Gunsons plan. All i know is that the Gunson plan was also significantly rotated compared to the raw ceph and at least very similar to the one from cephx. The other surgeon I think is known to rotate it even further than whats normal and by this being a bit more agressive with the rotations. So the conclusion was that regardless where I send the raw ceph, everyone agrees that this is not the format we work with and it deviates quite a bit in the same direction. Just by looking at the raw ceph it's not clear to me that I should have ccw. But by looking at the ceph when either the surgeons or cephx have stardardized it to their standard, it becomes more clear. So just by getting it in the right region of orientation it's much easier to look at it.

I think it's important to understand that cephs don't seem to be taken with a general standard and it can be very hard to just look at it out of box and in this case e.g know if ccw rotation is appropriate or not.

But yes, we agree. When rotating to a standard, the accuracy of the points used to define this standard defines the accuracy of the orientation.

StudyHacks

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Re: Recessed Jaws, What do you think?
« Reply #22 on: September 24, 2019, 04:36:19 AM »
Not sure how to respond, you state pretty clear what you want.

Well. If you consider your jaws recessed, then there's only one remedy, to advance them. The term for a surgery to advance both jaws is bimax, and the "s" after "jaw" indicates that you want both jaws advanced. So if you're looking for the term that describes what you're asking for, then you're right. It's "Bimax", and possibly "genioplasty" to adjust the chin individually.

Again, forward projection translates to advancement. If you want more forward projection, that means to advance the jaws. If I see correctly, you seem to have a class I bite, so it's basically to maintain the oclussion and displace them more forward to your liking, maybe some ccw rotation for projection of the lower face. Have you had any extractions or previous orthodontics?
How much movement of the maxilla and mandible, individually, should I get based on these CEPH images? I was told by someone knowledgable to get 7mm maxillary and 1cm mandibular advancement

Dogmatix

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Re: Recessed Jaws, What do you think?
« Reply #23 on: September 24, 2019, 10:31:50 AM »
How much movement of the maxilla and mandible, individually, should I get based on these CEPH images? I was told by someone knowledgable to get 7mm maxillary and 1cm mandibular advancement

You have 2 full pages adressing your case, read them. You should understand that this is a question you can't ask here. On the forum you can get help understanding the difference between different procedures. If you have decided on a procedure and want to get into details, you need to consult with a surgeon and ask what he can do, and then you can ask again on the forum if it sounds legit. How does it benefit you to have someone from here who can't offer you a surgery, to tell you some bogus mm?

Post bimax

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Re: Recessed Jaws, What do you think?
« Reply #24 on: September 24, 2019, 10:51:18 AM »
You have 2 full pages adressing your case, read them. You should understand that this is a question you can't ask here. On the forum you can get help understanding the difference between different procedures. If you have decided on a procedure and want to get into details, you need to consult with a surgeon and ask what he can do, and then you can ask again on the forum if it sounds legit. How does it benefit you to have someone from here who can't offer you a surgery, to tell you some bogus mm?

Give up. Whatever bone growth this guy is missing in his jaw is made up for by the impenetrable barrier that is his skull.

StudyHacks

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Re: Recessed Jaws, What do you think?
« Reply #25 on: September 24, 2019, 11:34:37 AM »
Give up. Whatever bone growth this guy is missing in his jaw is made up for by the impenetrable barrier that is his skull.
No, I'm sorry, you are right. I'll consult with the surgeon then report back on what he told me and then could you guys please help me afterwards?

Post bimax

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Re: Recessed Jaws, What do you think?
« Reply #26 on: September 24, 2019, 01:01:15 PM »
No, I'm sorry, you are right. I'll consult with the surgeon then report back on what he told me and then could you guys please help me afterwards?

Yes, but be sure to make notes of your discussion and keep any x-rays, scans, and tracings the surgeon provides you.  If a surgeon gives you a surgical plan then it's possible to critique it.

kavan

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Re: Recessed Jaws, What do you think?
« Reply #27 on: September 24, 2019, 03:19:50 PM »
Looks like I exaggerated when I said massively rotated lol. It's only 3-4 degrees.

This surgeon ended up using the same Dolphin 2d planning software/analysis as Gunson.  So basically (well at least with 2d cephs ) they seem to orientate to FH, and then pop the TVL perpendicular to it and through 'subnasale'.

YES. The construct of what they call the TVL isn't really parallel to the plumb line of gravity. It's diagonally oriented away from that as to be perpendicular to an FH when the FH isn't a pure horizont.  Now the boring part:

Gunson uses ARNETT'S ceph measure program/analysis and I think a number of docs in Spain do too, 'Nemo FAB'..something like that. Maybe in addition to Dolphin. But could be instead.

It's based on  aesthetic paradigms of people who have an 'ideal' balance with reference to the plumb line of gravity and also horizontal relationships that run perfectly perpendicular to it who very well, might have FH that are true horizonts. The aim is to bring patients, who deviate from that, CLOSER to those types of relationships with reference to the soft tissue profile.

An example of an person having the ideal paradigm the Arnett analysis is based on would be someone where a plumb line vertical would pass through around the bottom of their nose bone, through subnasa, the lips would flip a little forward to it and the Pog chin point would be posterior to it especially on a female. They would also have planes perpendicular to that line. For example, if you passed a horizont through subnasa, ANS-PNS would be pretty much aligned to it and their FH, very well could be a pure horizont.

So, basically, the paradigm used for this comes from people who have orientations of parts relative to the PLUMB LINE of gravity and orientations relative to a pure horizont. Their natural structure is oriented that way.

With regard to rotating a ceph, they kind of know that someone say with recession to lower face, would tend to tilt their head up to compensate for some recession there or they can just tell, the person is doing such and has the wrong tilt for what they want to reference for surgery plan. So, they rotate downward with reference to where they want to CONSTRUCT a 'vertical' to pass through aproximately bottom of nose bone, through subnasa and along upper lip. But in reality, with reference to the plumb line of gravity it's not a 'true' vertical . The true line of gravity is seen on the ceph stat. So, in essence, what say Gunson, would call a 'true' vertical after ROTATING a ceph where a  perpendicular would pass through the places he wants it to pass through, the construct is a DIAGONAL oriented away from the plumb line of gravity.

That's all well and good because it pretty much aimed at getting closer to the relationship of ideal alignment of the soft tissue profile that people with orientations aligned with true plumb line of gravity and pure horizonts have because the construct of what they call the 'TVL' will be perpendicular to a 'horizontal' plane that's not a 'pure' horizont eg an FH that's oriented away from a pure horizont.

In your case, it looks like they did a good job aligning your head tilt for the ceph. The  PLUMB LINE vertical (green one I drew parallel to vertical of ceph stat) passes through bottom of nose bone, subnasa and pretty much along upper lip which is kind of close to the Gunson type TVL. From there, they would look at the pure horizont perpendicular to it where they can see your FH is about 4 degrees rotated away from that. So, that black line which they CALL the 'TVL' in your case is a construct oriented 4 degrees AWAY from the plumb line of gravity as to be PERPENDICULAR to your FH.


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kavan

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Re: Recessed Jaws, What do you think?
« Reply #28 on: September 24, 2019, 05:42:21 PM »
I actually haven't compared it exactly and meassured the degree of rotation with e.g Gunsons plan. All i know is that the Gunson plan was also significantly rotated compared to the raw ceph and at least very similar to the one from cephx. The other surgeon I think is known to rotate it even further than whats normal and by this being a bit more agressive with the rotations. So the conclusion was that regardless where I send the raw ceph, everyone agrees that this is not the format we work with and it deviates quite a bit in the same direction. Just by looking at the raw ceph it's not clear to me that I should have ccw. But by looking at the ceph when either the surgeons or cephx have stardardized it to their standard, it becomes more clear. So just by getting it in the right region of orientation it's much easier to look at it.

I think it's important to understand that cephs don't seem to be taken with a general standard and it can be very hard to just look at it out of box and in this case e.g know if ccw rotation is appropriate or not.

But yes, we agree. When rotating to a standard, the accuracy of the points used to define this standard defines the accuracy of the orientation.

Well, your cephs were rotated with reference to the Arnett analysis, also used by some Spanish doctors and others. The Nemo-FAB software company, designed around it, is in Spain.

The difference between your profile and Study Hacks is that IF I drop a PLUMB LINE vertical from the near the bottom of the nose bone pretty much close to where where Gunson drops his 'TVL'  SH's, is pretty close already to the places  where Gunson wants a reference vertical; one dropped near bottom of nose bone that passes through subnasa, near or close to upper lip and so chin point is posterior to it.  He also looks to have what pretty much looks like he has an FH that is a 'pure' horizont. Basically, a situation where his ceph doesn't need to be rotated because his plumb line vertical (which is a 'true true' vertical) is pretty close to where Gunson would drop a 'TVL' after rotating someone ceph.

On your profile, it's pretty easy to see that you're compensating for recession by tilting your head up which is very COMMON position to hold head when someone has retrusion. The other tip off is the high SN line orientation. So, right there, they can tell they need to rotate downward.

Now, if I drop a PLUMB LINE vertical from the bottom of YOUR nose bone (or near that) where Gunson wants his 'TVL' to drop from, so it kind of intersects the base of your nose, your lips and chin are way AHEAD of that. So, in order to get a TVL dropped from near that part of the nose bone that also intersects with subnasa, runs along or close to upper lip and for the chin point is POSTERIOR to it, they had to rotate YOUR ceph by about 7 degrees.

So the difference is that a vertical reference line that is in the direction of real gravity (plumb line vertical which is same thing as vertical on the ceph stat) can be drawn on SH's ceph without having to rotate it AND what looks to be a pure horizont can be found. But on yours, the act of DROPPING a plumb line vertical from the bottom of your nose bone reveals subnasa, upper lip, lower lip and chin point is WAY AHEAD of that line. So, on YOU, they rotated about 7 degrees and by doing that, they constructed the 'TVL' from bottom of nose bone where the other parts of your face were more aligned with where they want them to be with reference.
SH's reference vertical is more of a 'true' TVL because it's aligned with a PLUMB LINE vertical.

Also, I don't think THEY put the red line you have on your ceph tracing. The line would be more along the vertical of your upper lip. Your red line is anterior to intersecting subnasa. Also, that red vertical line where you have it on your ceph tracing would convey your maxilla was to backward and to bring forward. So, I DON'T think the red vertical where you put it is the Gunson TVL (or anybody elses). If you drop the vertical from the BOTTOM of your nose BONE, THAT one would be the vertical that also passes through subnasa, runs along border of lip and for which the chin point is POSTERIOR to it but LESS so.

In essence, I don't think ceph X by DEFAULT rotates everyone's ceph and most certainly not 7 degrees as you rotated SH's. Having to rotate a ceph is not going to apply to everyone. If a PLUMB LINE vertical can be dropped from pretty much where Gunson drops his 'TVL' (near bottom of nose bone) which it can be on SH and that vertical happens to be oriented close to the places Gunson wants his TVL to be near, that person doesn't need their ceph rotated. (If they do, ceph X will know how much.) It's not something where if they rotate person A's ceph by X degrees, then person A rotates person B's ceph by same X degrees. It's not like that.

So, dropping a vertical from near bottom of nose bone on YOUR ceph, clearly revealed that the rest of your face was TOO AHEAD of it. Hence a rotation needed. But on SH's ceph, a vertical and mind you a 'true true' one aligned with the plumb line of gravity dropped from the bottom of his nose bone did NOT reveal that. That's a pretty salient difference where his profile was NOT like yours.

This is very hard to explain verbally because it's geometry. I just see WHY they rotated your ceph. But it's something to get a 'TVL' that's close to where SH's plumb line vertical already is pretty close to.

I wrote about similar to a post to April on this string as to what they call 'TVL' differing from the plumb line of gravity.

As to SH, he's just one of those people on Lookism who wants to 'mog' the others there and I guess someone from there must have told him his maxilla was 'recessed'. So, that's where he's operating from. Just so you know that.
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kavan

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Re: Recessed Jaws, What do you think?
« Reply #29 on: September 24, 2019, 05:50:20 PM »
Give up. Whatever bone growth this guy is missing in his jaw is made up for by the impenetrable barrier that is his skull.

LOL.  10 to 1, someone on Lookism probably told him he was that much recessed and/or he wants to 'mog' the types found there.
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