Custom plates

[PloskoPlus]

https://www.jawcenter.la/wp-content/uploads/2017/10/JAW_SURGERY.pdf

Never knew these bums guys were so advanced.
 
"The process involves our team liaising with maxillofacial digital technicians in France and Belgium. After uploading your CT scan to them, they will exactly reproduce the surgical plan you have already approved.
Once completed, your surgeon sits down via teleconferencing with an international team of technicians, connecting Australia, Belgium and France."

I wonder who these "technicians" are.

[PloskoPlus]

The custom "0 relapse guaranteed" plates that I've seen are enormous and look like iron masks.  But here they make big custom guides for the surgeon, but the custom plates are small.  I guess this is more of an aid to the surgeon rather than a relapse guarantee.

http://orthofacial.es/wp-content/uploads/2017/09/custom-machined-miniplates.pdf

[Ivano95]

The custom "0 relapse guaranteed" plates that I've seen are enormous and look like iron masks.  But here they make big custom guides for the surgeon, but the custom plates are small.  I guess this is more of an aid to the surgeon rather than a relapse guarantee.

http://orthofacial.es/wp-content/uploads/2017/09/custom-machined-miniplates.pdf

Dr. C has said that the 0 relapse guarantee is because the condyles would be pretty much near 100% stable post op due to the accuracy of the planning and not a direct result of the plates themselves.

[april]

"The process involves our team liaising with maxillofacial digital technicians in France and Belgium. After uploading your CT scan to them, they will exactly reproduce the surgical plan you have already approved.
Once completed, your surgeon sits down via teleconferencing with an international team of technicians, connecting Australia, Belgium and France."

I wonder who these "technicians" are.

I wouldn't worry about the technicians because the above sounds like the typical virtual surgical planning process that most surgeons who use VSP go through. Surgeons liaise with the technicians to agree on and submit the 3d plan, the technicians then 3d print the splints, and also - depending on surgeon preference - print cutting/drilling guides and custom plates.

These ones would be from DePuy Synthes and Materialise if based in Belgium. Brochure here.

Although custom plates are apparently more rigid, there is no zero relapse guarantee.

[PloskoPlus]

Dr. C has said that the 0 relapse guarantee is because the condyles would be pretty much near 100% stable post op due to the accuracy of the planning and not a direct result of the plates themselves.

AFAIK vertical maxillary downgraft relapse is more from the mastication forces then anything.
http://www.grsaudio.com/My_Media/PDF/Newsletters/OM/Critique%20OM%2028-6.pdf

FWIW, even though my ortho said I bruxed just as I got into braces, I was never aware of myself clenching... until after surgery, and I had no downgrafting.  I did have a net CW rotation from the uprighting of the teeth to fix the deep bite (and probably the LF1 advancement).  So I think the muscles were still stretched and kind of want to go back to where they were before all this ortho/surgery s**t.  I'd imagine it would be worse with a downgraft.

[Dogmatix]

What I understand it's rather uncommon to use custom plates, why is that? Custom splints I've heard many use, but haven't heard any of the big names using custom plates.

[kavan]

What I understand it's rather uncommon to use custom plates, why is that? Custom splints I've heard many use, but haven't heard any of the big names using custom plates.

I think the standard ones might come in 1-2 mm 'jumps'. Something where after the doc plans the surgery, for which he can use a VSP to plan it, there would be a variety of plates to choose from to fit the surgically planned displacements. Principle of 'best fit'. Basically, there's always the option to plan with the VSP and make a judgement call as to 'how close' or 'how exact' do things really have to be. The VSPs plan out things to a small FRACTION of a mm where such small fractions might make an insignificant difference to the outcome. For example, let's say the VSP has it that an 'exact' fit is say 1/10 of mm deviation from the STANDARD plate or some other deviation that would make an insignificant difference to just using a standard plate. Judgement call would be in favor of using the standard plate.

The custom plates fit exactly to the CONTOURS of the bone but the 'cost' of that or the EXCHANGE for that just to get things within a small FRACTION of a mm is a LOT OF SCREWS in the bone because it takes a lot of screws to make them flush with the contours.

So, the question is; 'How close do you really have to get it to the fractional differentials a VSP gives?' OR 'Is it worth it to use all those screws in face when the exact differencials kicked up by the VSP wouldn't make that much of a difference at all, be insignificant to the outcome?

Basically, how many multiple screws do you want in your face to get within 1/10th of a mm exactitude.

IMO, a good surgeon would be able to make that judgement call whereas a lesser one might not be able to and/or could be more inclined to just DEFAULT to the exactitude of the VSP.

[Dogmatix]

I think the standard ones might come in 1-2 mm 'jumps'. Something where after the doc plans the surgery, for which he can use a VSP to plan it, there would be a variety of plates to choose from to fit the surgically planned displacements. Principle of 'best fit'. Basically, there's always the option to plan with the VSP and make a judgement call as to 'how close' or 'how exact' do things really have to be. The VSPs plan out things to a small FRACTION of a mm where such small fractions might make an insignificant difference to the outcome. For example, let's say the VSP has it that an 'exact' fit is say 1/10 of mm deviation from the STANDARD plate or some other deviation that would make an insignificant difference to just using a standard plate. Judgement call would be in favor of using the standard plate.

The custom plates fit exactly to the CONTOURS of the bone but the 'cost' of that or the EXCHANGE for that just to get things within a small FRACTION of a mm is a LOT OF SCREWS in the bone because it takes a lot of screws to make them flush with the contours.

So, the question is; 'How close do you really have to get it to the fractional differentials a VSP gives?' OR 'Is it worth it to use all those screws in face when the exact differencials kicked up by the VSP wouldn't make that much of a difference at all, be insignificant to the outcome?

Basically, how many multiple screws do you want in your face to get within 1/10th of a mm exactitude.

IMO, a good surgeon would be able to make that judgement call whereas a lesser one might not be able to and/or could be more inclined to just DEFAULT to the exactitude of the VSP.

Hmm ok. Maybe I don't understand the normal plates correctly.
What I've seen, they look something like this.
https://i.ytimg.com/vi/Ewg0_Bct1Yk/maxresdefault.jpg

To me, using plates like these seems more or less like doing surgery by free hand. I mean, the maxilla could easilly be displaced differently with the same plates. And for sure the mandible, there's nothing on the plate limiting to advance more or less, and there's no fixation between the front and back plate on the maxilla.
That would be the reason I would see for custom plates, because it would take out any need to judge and meassure anything during surgery and make it more like assemblying a lego model and full accuraccy.

Do you really think custom plates can render a surgical outcome with 1/10 of a mm? It's still being done by hand, and even if the plates are printed with such accuracy, they need to be placed perfectly with no slipping when applying them.

[PloskoPlus]

The best surgeons claim 1 mm accuracy.

[kavan]

Hmm ok. Maybe I don't understand the normal plates correctly.
What I've seen, they look something like this.
https://i.ytimg.com/vi/Ewg0_Bct1Yk/maxresdefault.jpg

To me, using plates like these seems more or less like doing surgery by free hand. I mean, the maxilla could easilly be displaced differently with the same plates. And for sure the mandible, there's nothing on the plate limiting to advance more or less, and there's no fixation between the front and back plate on the maxilla.
That would be the reason I would see for custom plates, because it would take out any need to judge and meassure anything during surgery and make it more like assemblying a lego model and full accuraccy.

Do you really think custom plates can render a surgical outcome with 1/10 of a mm? It's still being done by hand, and even if the plates are printed with such accuracy, they need to be placed perfectly with no slipping when applying them.

Yes, that's what the standard ones look like. Fewer screws. Yes. The maxilla could be displaced differently with the same plates. But not outside the 'jump' they give. Besides, I think it's the custom vsp SPLINTS used that allow for the line up as far as maxilla + mandible movement go. Standard plates could be selected to fixate that. Custom ones kind of 'broad base' over the bone curvature and for that reason are going to take more screws.

The custom plates would be consistent with the measures of the VSP program where on the read out one can see small fractions of a mm such as something moving .1mm. But still, within 1mm would be sufficient and they do seem to 'exacting' for a doc to do by hand.

IDK, just looks like too many screws, too much extra hardware to deal with.

Are the doctors you consulted with who gave you their VSP plans going to be using the custom ones on you?

[kavan]

The best surgeons claim 1 mm accuracy.

Sufficient enough NOT to have to use custom plates.

[april]

From the xrays sent to me by 3 patients who have Materalise custom plates, there seems to be about 16 screws on the maxilla and 8 all up on mandible. The main difference I see is the amount of metal - there is metal bar on the maxilla connecting the two sides. My concern was if that bothered them. They didn't notice any issues though. One patient was at least 2 yrs out from surgery.

KLS martin also make custom plates, but (only going from diagram on their website) they don't seem have that extra metal connecting the pieces.

[Dogmatix]

Are the doctors you consulted with who gave you their VSP plans going to be using the custom ones on you?

I have asked actually, but got a bit ambigious answear. I asked if custom plates was used for surgery, and got something like
-Yes, we have a medical 3d printer which creates custom made pieces for every surgery.
But to me that seems like a bit too general response for a specific question about custom PLATES. I know they use a medical printer to print custom splints, which is something else. I'm not sure if such printer is even capable of printing surgical plates and guides.

How I see it, the splint guides the occlusion. You make a custom splint which fits to the teeth, and fixate the bite and the maxillomandibular complex. Custom plates would be an additional step to guide the displacement of the complex in relation to the skull.

My comprehension is that none of the big name surgeons I've heard of use custom plates.
The comfort with custom plates for a patient would be that it seems like you don't really need a very good surgeon, as it would be to just follow the guides. I think quantifying and making the process easy is something good. I mean, creating a VSP actually don't seem very hard if you understand the basics, and if you also can make custom plates that any surgeon can use, then it seems like a great step forward for jaw surgery. There is at least one thing you don't wish to hear or notice after a surgery as a patient, and it's that the result doesn't correspond to the plan, and have it explained with how hard it is to operate with more accuracy. I mean, you want what the predefined plan showed you,

[Dogmatix]

The best surgeons claim 1 mm accuracy.

A study published on accuracy between VSP and CMS, concludes it's about 1.2 +-1mm accuracy. Then it can of course be that the "best surgeons" are in the better region.
I'm just trying to think rationally. I've done some work by hand where I want accuracy from time to time, renovating etc. In those cases I do it in a controlled environment, have all the space and time I need.
To perform work with 1mm or less accuraccy within someones mouth, in a multi variable situation with displacement of maxilla and mandible and blood and tissue everywhere, seems impossible. I have no problem with thing being impossible, we're not consulting with magicians, but I think it's problematic if someone claims to be able to perform magic.

https://www.ncbi.nlm.nih.gov/pubmed/28950997

[kavan]

I have asked actually, but got a bit ambigious answear. I asked if custom plates was used for surgery, and got something like
-Yes, we have a medical 3d printer which creates custom made pieces for every surgery.
But to me that seems like a bit too general response for a specific question about custom PLATES. I know they use a medical printer to print custom splints, which is something else. I'm not sure if such printer is even capable of printing surgical plates and guides.

How I see it, the splint guides the occlusion. You make a custom splint which fits to the teeth, and fixate the bite and the maxillomandibular complex. Custom plates would be an additional step to guide the displacement of the complex in relation to the skull.

My comprehension is that none of the big name surgeons I've heard of use custom plates.
The comfort with custom plates for a patient would be that it seems like you don't really need a very good surgeon, as it would be to just follow the guides. I think quantifying and making the process easy is something good. I mean, creating a VSP actually don't seem very hard if you understand the basics, and if you also can make custom plates that any surgeon can use, then it seems like a great step forward for jaw surgery. There is at least one thing you don't wish to hear or notice after a surgery as a patient, and it's that the result doesn't correspond to the plan, and have it explained with how hard it is to operate with more accuracy. I mean, you want what the predefined plan showed you,

The custom splints and custom pieces eg the down graft material shape from the VSP are much more important than the custom plates.

The VSP read out tells the surgeon what the displacements are. Although they might be listed with small fractions of 1mm, eg. 1.1mm, a standard plate can be selected to fixate that displacement.