Long-Term Stability of CCW rotation via Posterior Downgraft of the Maxilla

[Post bimax]

If there's already another thread about this, point me in that direction.

My question is whether there is scientific consensus on the long term stability of posterior maxillary downgrafts.  I haven't been able to find much research on this (outside of Wolford).  I read about a lot of surgeons saying ccw is 'unstable', and I read a lot of people saying this is just sour grapes because they can't actually do it themselves. 

I think this is one of the most important questions in JS.  For many people, CCW-r via posterior maxillary downgraft is the route to an optimal aesthetic outcome which is generally a major concern for people undergoing JS.  The fact that some surgeons say it's just as stable as straight MMA and others say to expect a full relapse within 5 years is disconcerting.

I guess I'm looking for a few things here:

1. Any additional scientific literature on the long-term stability of ccw rotation via posterior downgrafting of the maxilla

2. Personal or second-hand experiences with posterior downgrafts

3. General opinions on the topic


Thanks guys

[GJ]

My opinion is it depends on the grafting.

(a) is there enough excess bone from the jaw surgery to use in a graph?
(b) does the surgeon have skills in doing that graft?
(c) does the surgeon allow proper healing time of the graft (e.g. some will do the graph, then tell you to chew as soon as possible)

It's amazing the amount of incompetence out there just on those three issues. If there is excess bone, the graft is done right, and there is proper healing time, it should be stable. The one complication out of anyone's control is that the body might reject the graft. This is more unlikely if it's your own bone, which is why (a) is important. The surgeons who report stable results and argue with the logic that the graph is unstable probably know how to handle the three points above. There's a lot of literature about the topic, and you just need to use Google or the "education" section here.

[Post bimax]

My opinion is it depends on the grafting.

(a) is there enough excess bone from the jaw surgery to use in a graph?
(b) does the surgeon have skills in doing that graft?
(c) does the surgeon allow proper healing time of the graft (e.g. some will do the graph, then tell you to chew as soon as possible)

It's amazing the amount of incompetence out there just on those three issues. If there is excess bone, the graft is done right, and there is proper healing time, it should be stable. The one complication out of anyone's control is that the body might reject the graft. This is more unlikely if it's your own bone, which is why (a) is important. The surgeons who report stable results and argue with the logic that the graph is unstable probably know how to handle the three points above. There's a lot of literature about the topic, and you just need to use Google or the "education" section here.

This is interesting. Posnick told me he uses cadaver bone for grafts and that it's just as stable as your own bone.

[kavan]

I'm not sure I know what they mean when they say a posterior downgraft is unstable because with reference to Gunson (and maybe Wolford) and I think Alfaro, they use the hydroxyappatite blocks and those don't go anywhere. They don't dissolve or anything. Maybe they mean a large one is a lot on the jaw joint.

[Post bimax]

I'm not sure I know what they mean when they say a posterior downgraft is unstable because with reference to Gunson (and maybe Wolford) and I think Alfaro, they use the hydroxyappatite blocks and those don't go anywhere. They don't dissolve or anything. Maybe they mean a large one is a lot on the jaw joint.

I've had this question as well.  Maybe they disintegrate?  I don't know.

[GJ]

This is interesting. Posnick told me he uses cadaver bone for grafts and that it's just as stable as your own bone.

Cadavar bone is fine and should be as stable assuming your body doesn't reject it for some reason, which does happen.
I've heard the same can happen with HA, though Kavan says no. I'm not sure on that one.

[kavan]

I've had this question as well.  Maybe they disintegrate?  I don't know.

No. An HA block stays there. It doesn't go anywhere. That's what I don't understand when some docs say the down graft is not stable.

[PloskoPlus]

No. An HA block stays there. It doesn't go anywhere. That's what I don't understand when some docs say the down graft is not stable.

Not sure about others, but Wolford uses porous HA blocks. They don't get replaced with bone either, but are apparently easier to cut and shape and integrate better with your bones.

[kavan]

Not sure about others, but Wolford uses porous HA blocks. They don't get replaced with bone either, but are apparently easier to cut and shape and integrate better with your bones.

I think all the HA blocks used are porous. They have to be for bone to integrate. But the HA block stays there. It doesn't dissolve or anything.

[PloskoPlus]

I think all the HA blocks used are porous.

Most likely that's the case now.  Although I think when Rosen first started using HA blocks they were solid.

https://www.tandfonline.com/doi/pdf/10.1080/08998280.1999.11930185?needAccess=true

[PloskoPlus]

Wolford told me that cadaver bone becomes soft as it heals.  He said it's a problem with any kind of bone… As it revascularises, it takes out all the calcium and then puts it back in again.

If what he says is right (and I tend to believe him), this is why large bone grafts are unpredictable and surgeons use bigger grafts than necessary to account for immediate relapse and a good ortho is vital to fine tune the last couple of mms.

OTOH, I've heard that porous HA is not as strong as real bone long term and relapses very slowly (1% a year).   But bone grafts get replaced with your own bone eventually and the area becomes as strong (or weak) as your own bone.

So: relapse now vs later.  CCW critics say Wolford has no long term data to prove his results are stable.  But they themselves have no proof of that their simple linear surgeries are stable either.  In fact, I think Wolford has probably some of the longest follow up cases published.  The average surgeon will not see you a year past your surgery.  In general maxillofacial surgery has very few long term studies period.

[kavan]

Most likely that's the case now.  Although I think when Rosen first started using HA blocks they were solid.

https://www.tandfonline.com/doi/pdf/10.1080/08998280.1999.11930185?needAccess=true

Hard to imagine they would use a solid. But ya, the article said so. Needs to be porous for the bone and other tissues to grow into it (to help hold in place).

[Lazlo]

f**k I didn't know that the grafted material is HA for posterior downgrafts. I mean what if they shatter or break or something? They won't heal like natural bone would heal would they? At least with the cadaver bone it eventually becomes your own bone.

[PloskoPlus]

f**k I didn't know that the grafted material is HA for posterior downgrafts. I mean what if they shatter or break or something? They won't heal like natural bone would heal would they? At least with the cadaver bone it eventually becomes your own bone.

It doesn't have to be, but Wolford uses only porous HA.  What others use is all over the place.  Alfaro was said to use HA, then we had one of his patients here with a massive downgraft which was bovine (AFAIR).  Gunson said "bone scraps" from the osteotomies would be sufficient for my 4 mm posterior down graft.  Maybe he uses porous HA for bigger down grafts.