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Occlusal plane tipped down

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mazilla:
I had bimax surgery for sleep apnea 2 years ago. Ever since I felt something was off. I felt I was advanced too much, and that I was left with bimax protrusion. I have now studied my pre and post op cephs on cephx.com and discovered that my occlusal plane was flat preop, but I had 10 degrees of CCW rotation anyways. Now I feel that is what makes me feel I look off, the unnecessary rotation. I was left class III and with a very small nasolabial angle due to the rotation.

I feel like my case was a simple case of straight advancement, but my surgeon gave me both anterior and posterior downgrafts although I did not want more tooth show and my occlusal plane was already flat.

Please help and advise.

 Pre: https://imgur.com/a/S8vzX
 Post: https://imgur.com/a/HVb0w

secondtimearound:
I told you in the other thread, your jaws were rotated too much CCW and your occlusal plane is unjustifiably tilted CCW now relative to all the rest of your facial planes which are in really good alignment.

You do not need the jaws moved forward or backwards at this point, as they are in great alignment from that perspective.

You need to decide if you need anterior impaction at this point. This is determined primarily by how much of your upper front teeth are visible when you part your lips at rest. For a man, you want at most 1-2 mm ideally. Women is more like 4 mm (rough estimate here). If you have more than 1-2 mm of teeth showing with your lips apart at rest or your smile has become gummy, you might benefit from some anterior maxillary impaction. But I don't think you need anterior maxillary impaction despite that you mentioned you believe you do. At most you could impact the anterior aspect 1-2 mm if needed.

Otherwise what you need is posterior impaction of the maxilla by at least 3-4 degrees to get your occlusal plane back closer to the normal range. This requires revision BSSO and LF1, as you can't reorient the maxilla without reorienting the mandible as well.

The rotation will help to retrude your lower jaw a bit which has become a bit overprominent from the prior surgery as well.

Sucks doesn't it? Hard enough going through these surgeries once. Let alone twice. I feel your pain. At least yours is a relatively simple case at this stage.

ditterbo:

--- Quote from: secondtimearound on January 01, 2018, 04:16:43 PM ---I told you in the other thread, your jaws were rotated too much CCW and your occlusal plane is unjustifiably tilted CCW now relative to all the rest of your facial planes which are in really good alignment.

You do not need the jaws moved forward or backwards at this point, as they are in great alignment from that perspective.

You need to decide if you need anterior impaction at this point. This is determined primarily by how much of your upper front teeth are visible when you part your lips at rest. For a man, you want at most 1-2 mm ideally. Women is more like 4 mm (rough estimate here). If you have more than 1-2 mm of teeth showing with your lips apart at rest or your smile has become gummy, you might benefit from some anterior maxillary impaction. But I don't think you need anterior maxillary impaction despite that you mentioned you believe you do. At most you could impact the anterior aspect 1-2 mm if needed.

Otherwise what you need is posterior impaction of the maxilla by at least 3-4 degrees to get your occlusal plane back closer to the normal range. This requires revision BSSO and LF1, as you can't reorient the maxilla without reorienting the mandible as well.

The rotation will help to retrude your lower jaw a bit which has become a bit overprominent from the prior surgery as well.

Sucks doesn't it? Hard enough going through these surgeries once. Let alone twice. I feel your pain. At least yours is a relatively simple case at this stage.

--- End quote ---

I'm more eyeballing the hypothetical changes then doing the definitive geometry on a ceph, but pretty sure any anterior impaction creates additional CCW, which you'd have to counterbalance with even more posterior impaction. Also keep in mind that some people have complications with anterior impaction, reducing support of their malar/submalar soft tissue and causing them to droop post op, making them appear older. Also, upper tooth show naturally reduces with age. I just don't see much upside with anterior impaction unless you really value poor upper tooth show over all this. IMO that's a compromise you should just accept as an objective improvement if you were to partially reverse the bimax.  Research whether bringing back the maxilla a tad would be less risky than an anterior impaction. I don't know myself but removing bone, from the front, sounds more risky than removing some of whatever they use to push the maxilla forward.

Posterior impaction sounds correct to me, but to clarify 2xaround,  pretty sure that does require redoing the BSSO such that the lower jaw/teeth are moved backward.  If he doesn't do a multi-peice lefort, then the upper incisors will flare out less, due to the posterior impaction, essentially reversing some of prominence in the upper lip and philthrum/that whole region (w/e it's called). 

Frankly though I don't get the issue with a divergent occlusal plane alone as the impetus for a revision, unless your open mouth smile looks off and is bothering you in the way it looks past your front incisors. Michael Phelps has a similar occlusal plane, I think.

kavan:

--- Quote from: mazilla on January 01, 2018, 05:02:06 PM ---What bothers me is not the occlusal plane itself, which I had not noticed until now, what bothers me is protruding mouth, protruding teeth (with I already had preop, but the CCW made much worse), mandible too far forward, and too small nasolabial angle.

I was downgrafted anteriorly and posteriorly in my 1st surgery, so if they remove the whole HA whatever they put in both my anterior and posterior maxilla, that would derotate my jaws by 10 degrees, and leave my occlusal plane as it was pre-op, and solve the things I dont like about my result. So the impaction would not be removing my own bone, but whatever they put in there to downgraft my maxilla.

I still dont get why I would need BSSO, my lower teeth would not need to move backwards, just my mandible being rotated with the maxillary rotation, but I might be missing something here.

--- End quote ---

Should be obvious that since your mandible was advanced about 2cm and a BSSO cut was part of that and since you don't like your 'over advanced' lower jaw, a BSSO cut would be needed to push it backwards.

ditterbo:

--- Quote from: mazilla on January 01, 2018, 05:02:06 PM ---What bothers me is not the occlusal plane itself, which I had not noticed until now, what bothers me is protruding mouth, protruding teeth (with I already had preop, but the CCW made much worse), mandible too far forward, and too small nasolabial angle.

I was downgrafted anteriorly and posteriorly in my 1st surgery, so if they remove the whole HA whatever they put in both my anterior and posterior maxilla, that would derotate my jaws by 10 degrees, and leave my occlusal plane as it was pre-op, and solve the things I dont like about my result. So the impaction would not be removing my own bone, but whatever they put in there to downgraft my maxilla.

I still dont get why I would need BSSO, my lower teeth would not need to move backwards, just my mandible being rotated with the maxillary rotation, but I might be missing something here.

--- End quote ---

Soft tissue is unpredictable is the point, particularly when you remove support of any kind, new or old. Just identifying risks.

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