Opinions on IMDO surgery?

[kavan]

My question was regarding movement of the jaws. If there is some elasticity in the fractured spots that can be pulled before it's settling.

Yes, I saw on your other post your question was regarding movement of the jaws. But also that people were referring to the use of 'elastics' to prevent movement of the jaws. So since one of your posts referred to moving something, my post referred to the same devices that used elastics (TADs) in reference to moving the TEETH. That is to say  they can use those things for fine tuning the bite past surgery; adjustments with reference to moving the teeth.

Now with reference to 'elastics' NOT moving the jaws, I think these 'elastics' people are referring to are the TADs. Since they are ANCHORAGE devices, they are used to anchor down the bite (assuming the bite comes out right post surgery) so the jaws stay in place. So, they don't move jaws nor are they aimed at moving the jaws.

To the best of my knowledge, the TADs used to anchor down a right bite post surgery so the jaws DON'T move  can also be used to move selected teeth to fine tune the bite. They ANCHOR down teeth not wanted to be moved so selected teeth can be moved.

The whole point of my entry depends on whether what people are calling 'elastics' are the TADs. If so, then they are used to ANCHOR the jaw in place by anchoring the bite so the jaws and/or they can be used to make fine tune adjustments to certain teeth without moving the other ones.

So, if they are referring to TADs and to TADs when the post surgery bite is right, they are used to ANCHOR down the bite so the jaws DON'T move. But to the best of my knowledge not used to move the jaws.

I also had CONFUSION via reference to 'elastics's and just wanted to clarify that if they are talking about the TADs, the MOVEMENT they refer to is either movement of selective teeth to fine tune/adjust OR to PREVENT movement of jaws post surgery. They are not aimed at moving the jaws. With reference to TADs, the only movement they would refer to is movement of selected teeth so the others stay in place.

So the DEVICES aimed at non movement also have capacity to move SOMETHING. But the 'something' the devices are aimed at moving (if that's needed post surgery) is selected TEETH. Not the jaws. With reference to 'movement' of the jaws, the devices are aimed at NON MOVEMENT of them.

All I wanted to add here was what devices WITH ELASTICS are called; TADs which can be aimed at anchoring down so the jaws stay in place or aimed at moving selected teeth into place while anchoring the other teeth so the other teeth don't move.


I can't actually answer the question about 'elasticity' of the 'fractured spot' with any reference to devices aimed 'pulling' the jaws 'before things settle'.

[kavan]

Well, fact is that there is a lot of people confused about IMDO. First time I read about it, it seemed like a non surgical procedure and it was not obvious to find this information, even though it's of course obvious for the one doing the surgery. It's also not obvious what the actual surgery is and how it differs from the fracture you do with BSSO. Can you tell us the technical difference in the cut you make for the IMDO™️?  Because if you want to separate a bone you need to fracture it, and how can we understand the difference in this fracture compared to BSSO and why it's better?

I also agree with Kavan on the nonsense of trade marking a procedure, making it harder to do research on and hindering it to be evaluated by other surgeons.

 CORRECT. The act of TRADEMARKING a term where within the TMed term is; 'Distraction Osteogenisis', (DO), IMO resolves to act of APPROPRIATING a term for procedures already in the public/scientific venue into one's trademark. This, in turn, results in posters equating or confusing DO with the TRADEMARK term; 'IMDO'. Because they see the TRADEMARK term that includes the term; 'DO', ask about that and then post LINKS to the practice of the OWNER of that TM. So, the act of TMing something with the term 'DO' in it often resolves to discussion about the TM term. That, in turn, positions JSF to provide a type of involuntary advertising exposure to the owners and practitioners associated with this TM each time a poster inquires about 'DO' with the PREFIX of 'IM' attached to it. Hence to acknowledge the TM term; 'IMDO' positions us to be defacto promoters of it if we DON'T critique how it's used and then confused in the act of marketing.

Straight out: A TM term is a financially motivated term for the purpose of branding. JSF would prefer that discussion of DO resolve to sources where the term 'DO' is NOT part of a TM term. For that reason:

I am offering links to some articles on DO because JSF often get inquiries about a TRADE MARK procedure that has within it 'DO'. JSF and mods thereof feel that posters in pursuit of information about DO (as it applies to moving the mandible) are better served by referring them to NON financially motivated academic sources that openly contribute to the scientific information to this venue than to those who appropriate the the term 'DO' into a TRADEMARK procedure for business branding.



"Distraction Osteogenesis of the Ascending
Ramus for Mandibular Hypoplasia
Using Extraoral or Intraoral Devices:

A Report of 8 Cases
Pilar Rubio-Bueno, MD, PhD,* Alicia Padro´n, MD,†
Esther Villa, MD,‡ and Francisco J. Dı´az-Gonza´lez, MD, PhD§"

https://s3-eu-west-1.amazonaws.com/hsd-sites/maaxilo/publicaciones/rubio_bueno_2000_mandibular_distraction_osteogenesis.pdf
-----
Intraoral mandibular distraction osteogenesis: special attention to
treatment planning

Pilar Rubio-Bueno,1 Esther Villa,2 Alberto Carren˜o,2 Luis Naval,1 Jesu´ s Sastre,1 Rafael Manzanares,3
Francisco J Dı´az-Gonza´lez1
1
Department of Oral and Maxillofacial Surgery (Head: FJ Dı´az-Gonza´lez, MD, PhD); 2
Department of
Orthodontics (Head: FJ Dı´az-Gonza´lez, MD, PhD); 3
Department of Radiology (Head: D. Tagarro, MD,
PhD) Hospital Universitario de la Princesa, Madrid, Spain

http://www.sld.cu/galerias/pdf/sitios/cirugiamaxilo/do_planificacion_del_tratamiento.pdf

[Sergio-OMS]

Hi, I will try to write a single message. After reading some messages I felt like I was not qualified to participate in this forum (put it politely).

I will try to follow an order and I will start from a message posted previously to my first one. I hope I don't make any mistakes as I am editing the message separately.

But don't they do similar adjustments with the elastics after surgery and try to pull it while they can?

Those adjustments are done sometimes. This is normally called "floating bone" technique or concept. Widely used in other techniques of mandibular and maxillary distraction. And even after conventional orthognathic surgery, after a 3 piece Le Fort, the central part (the premaxilla) can be managed that way by the orthodontist. This requires not to place a final split (or remove it early, after a few days) and choose other method of transverse stabilisation.

Sergio, Thank you for posting your experience. I appreciate your participation in this, as IMDO is a bit of an enigma to me.  

Thank you for your words. I will try to help. IMDO can be a little bit difficult to be understood, even for experienced surgeons. It is always difficult to think outside the box.

I would like to start by saying i've personally had a negative experience interacting with Dr. Coceancig on one of the facebook maxillofacial surgery boards.  At the time I was considering having him IMDO me and that experience had him knocked off my list.

I understand perfectly, and I am sure you did the right thing. It is important that both patient and surgeon are on the same wavelength.

MARPE - Microimplant assisted rapid palate expansion, developed by Dr. Won Moon at UCLA has shown excellent results in maxillary expansion and subsequent airway expansion.  Is that what is used in conjunction with IMDO to balance the midface?  Is there no Maxillary or Midface Distraction technique?

I think the device developed by the UCLA team led my Won Moon is the MSE. Maybe MARPE concept precedes Moon work? Anyway, it is not an important thing, it's just a detail.

MSE type-2 is the one I prefer to use in the few cases I am doing. Other surgeons use other expanders or do a SARPE in adult patients.

To answer your question please see the following short video:  https://youtu.be/pTiL4g8PEv0?t=2     Maxillary expansion is part of the protocol. In fact, with MSE (and I am sure other devices)  it is a transverse non-surgical midfacial distraction.

But I suppose you also want to ask about the forward movement of the upper jaw.  Yes, we need overjet. If there is no overjet that should be addressed (before or simultaneously). It means proclining the upper teeth or accepting to have a Le Fort I done.

In an interview with Arnett and Gunson, Dr. Dipak Chudasama asked: Do you believe skeletal distraction can replace some orthognathic surgeries?

Dr Gunson Responded: Distraction osteogenesis, in our opinion, will not substitute for conventional orthognathic surgery. Well-done orthognathic surgery with rigid fixation produces occlusal, facial, and airway results that are the gold standard. Distraction osteogenesis does not, and will not, treat the bite in three planes of space with the same quality and precision as conventional, well-done orthognathic surgery. When thinking of distraction, we must realize its limitations. Establishment of precise vectors for distraction is exceedingly difficult. Moving a complex object such as the mandible to within 1mm of accuracy is a veritable impossibility with distraction. There are also severe limits on achieving final occlusion compared with traditional orthognathic surgery. What are the valid clinical reasons to avoid the Le Fort I and sagittal osteotomies in favor of distraction? Previously held beliefs that distraction was kinder to nerve and joint tissues have been proved false. We must be careful not to lower our standards for the sake of using new technology. Distraction does have clinical relevance when trying to correct large deformities in skeletally immature patients. Treacher-Collins patients often require early intervention to improve airway patency, and distraction can provide this. Severe hemifacial microsomia patients might also require distraction to increase the skeletal mass and structure in the condyle and ramus areas so that future orthognathic surgery can be successful.

Based on your post, Id imagines you'd hold a somewhat contrary point of view, so I would like to hear your take on this statement.

Thanks.

I agree with Dr. Gunson almost completely. Distraction osteogenesis has its limitations, even if done as an inter molar osteotomy (trademarked or not), as a ramus distraction or as any other distraction technique. But so do BSSO, MMA and CCW have limitations and risks. All of them are tools in the surgeon's armamentarium.

For instance, the larger the osteotomy gap of the BSSO, the higher the risk of relapse (and the larger the relapse). Not only due to the instability of the osteosynthesis but also because of the risk of condylar resorption. Several authors recommend to consider the use of distraction if the planned gap is larger than 7 mm because of the long term relapse after BSSO in those advancements. Soft tissues (skin, muscles) adapt better with distraction.

What I do not agree with him is on the assumed statement that BSSO has to be accepted as the gold standard for every patient.

No, of course not with the purpose of moving. The jaws are put in the exact position they should be in and elastics to stabilise. But preventing movement also imply that they can move, and if they drift a bit and it's caught early enough, I meant that some strong elastics maybe can correct it. I don't know, it was more a question.

Precisely.

His IMDO videos are full of subterfuge, not making it quite clear that IMDO is best aimed during GROWTH STAGE. Hopes of it working as an isolated procedure is what brings in the consults about it. Fat chance adult consults about it will resolve in option for IMDO 'only' as can be offered to kids, adolescents, teens in growing stages in the absence of additional surgeries to go with it .

Hello kavan.

Well, maybe to me it is was not that way due to my background.  I never felt that way while watching those videos.

I have personally seen Paul removing distractors from a 28 year old female. And another friend of ours recently did an IMDO on a 40 year old female as a sole procedure, successfully. IMDO is a type of surgery-first procedure. Orthodontics has to continue afterwards. But that's planned from the very beginning. And sometimes more procedures are planned, specially in adult patients.

His IMDO videos are full of subterfuge, not making it quite clear that IMDO is best aimed during GROWTH STAGE.

Please see the first seconds of this one, from the same playlist: https://www.youtube.com/watch?v=chU4ImyeZl8&list=PLjC4hIwmyQfjXgckxslgVI9BPkh6wcv-a&index=12

You say IMDO is better for 'young adults', less risks than BSSO. Well ya, less risk than needing to get a BSSO in later life for jaw retrusion when the GROWTH STAGE has passed. So, what's a 'young adult' and why not use the term 'during GROWTH STAGE' instead? Term 'young adult' avoids using terms like 'teen' where it's just clearer they are in growth stage.

Young adults would be anybody under 35, but willing to accept the other inconveniences, risks and costs.

You admit, younger people as those in the GROWTH STAGE will get more out of this and those past that can have it with OTHER surgeries. But consider, this board's main population is OVER 18, past the growth stage and for the most part curiosity about IMDO is with hope they can have this as SOLE procedure. So, I tell them it's highly unlikely someone in their 20's or so will be offered the IMDO INSTEAD of a BSSO and the consult they go on hoping they can get that only (as a kid could) will resolve to being suggested OTHER surgeries.

That's what I am trying to clarify here.

So, tell me, how likely is it that say a 20 year old or someone passed the growth stage wanting say, a 5-7 mm advancement will be offered by you and your associates IMDO only?  OK, you could say, it depends. So straight out, what percentage of  ADULTS, those PAST the growth stage are given IMDO only?

There is a need to address the maxilla. And we need the overjet. Given a good candidate, this procedure could be offered as a sole procedure.

Now again the board is aimed at at least over 18. But better if they are over 20.

Sorry, I did not know that this forum was for discussing adult surgery only.  maybe you could change the domain name?    just kidding 

They are not candidates for the max benefits IMDO yields to those in the growth stage. So, my question as the mod (and the one who critiques your associate) is: 'Shouldn't these ADULTS past the GROWTH STAGE be told IMDO as sole procedure to advance jaw is unlikely to be the 'fix' for them as it would be for a kid?' Well I don't see the IMDO promoters telling them straight out. Telling them straight out would cut down the consults about them when those consults could lead to telling them they need other surgeries either instead or with and all because the HOPE of IMDO ONLY is used as kind of a marketing carrot.

I think you have made your point clear. But to the best of my understanding nobody has said these things. As I told you, the IMDO playlist on YouTube is quite clear what the perfect candidate would be. And it also even explains the surgical technique!

Then the TRADEMARK procedure doesn't sit right with me. I have more respect for doctors who share technique in medical venue than those who TRADEMARK it.  This is something OTHER doctors COULD do but if they use the term; 'IMDO', he's got a TM on it. So, unlike a 'BSSO' or a 'Lefort' or most other procedures in maxfax that are NOT trademarked, this guy has a trademark on his. A trademark is to BRAND.  So inquiries and discussions about 'imdo' resolve to giving exposure to his brand. Posters don't realize this is a TRADEMARK thing because it sounds like a generic procedure. He's certainly entitled to trademark his procedure and pose what ever contingencies he wants to others who agree to his terms in exchange for calling what they do; 'IMDO'. But JFS doesn't want to be positioned to be a defacto 'brand buzzer' when the term 'imdo' is used. Imagine if someone trademarked the term; 'BSSO'. Thankfully, 'BSSO' is not trademarked.  Each time the term is used, it's effectively a 'buzz' for his brand and given the history of his introduction and participation here why should JSF be defacto brand reps for him .

That said, in your opinion, what would be a good GENERIC term for a procedure that does the same thing that a variety of doctors could do WITHOUT using the trademark name?

Trademarks are not patents, as you know (besides, surgical techniques cannot be patented).  There are other surgeons there doing this procedure. What we want is to protect an image. Everybody knows  what a Big Mac is no matter the country, right?   We also do not want manufacturers to use the four IMDO letters as a brand without our permission to sell things.

To bad you never participated on any of the threads that were very informative. Just on this guy's.

Well I had more important things to do, no offense intended. And I think patients need places to communicate, kind of support groups away from surgeons and all the aggressive marketing being done all around. I was not sure if participating on this thread but I felt I had to do it as detected some wrong assumptions that could be clarified. Dr. Google is not always right!

Well, fact is that there is a lot of people confused about IMDO. First time I read about it, it seemed like a non surgical procedure and it was not obvious to find this information, even though it's of course obvious for the one doing the surgery. It's also not obvious what the actual surgery is and how it differs from the fracture you do with BSSO. Can you tell us the technical difference in the cut you make for the IMDO™️?  Because if you want to separate a bone you need to fracture it, and how can we understand the difference in this fracture compared to BSSO and why it's better?

Please have a look a two minutes of this video, starting at that precise point: https://youtu.be/YgWnUDQRlTs?t=1370   I hope it helps. And watch any BSSO video, I think you will see the difference. I will gladly answer you doubts after you watch it.

I also agree with Kavan on the nonsense of trade marking a procedure, making it harder to do research on and hindering it to be evaluated by other surgeons.

I think statements like kavan's about trademarking are based on wrong premises on trademarks and patents. I am not a lawyer, though, I am just a surgeon.

It does not hinder any one to research or publish, nor it prevents anyone to try to do the procedure. It's only a way to say who we are.  Call it a badge for a study club or treehouse friends club if you like, where we agree to follow the same protocol, share experiences, back each other and learn together for the good of our patients.

I hope everything is clearer now. Anyway, I've got the feeling that my words won't matter much   

[ben from UK]

Great to see a surgeon participating in discussions. I would like to see that more often, but I would understand surgeons don't want to post here under there actual name. On the other hand, it would be great if surgeons would share their knowledge openly, online. Many surgeons could learn from eachother, i have the feeling there isn't much communication between surgeons.

[Lefortitude]

Thank you Sergio for addressing our questions and sharing your experience. Its extremely valuable to us and to the body of information available to the public regarding these procedures to have a clinician step in and clarify or explain certain concepts.  I see it as a great service to the public.

I enjoyed reading your thoughts on the topic and would encourage you to continue to contribute in any way you feel appropriate.

There's an interesting dynamic nowadays between clinical practitioners and the public due to the access to information phenomena presented by the internet (places like this board as well).   I can understand why they are generally hesitant to post.  On the public side, we have such a vast and ever-evolving body of knowledge available to us, that no clinician could ever possibly keep up with all the latest research and papers coming out of universities around the world.  On the clinician's side, they have the practical EXPERIENCE and APPLIED KNOWLEDGE which no amount of research and reading papers online could ever give.  It creates a disparity between "the research shows..." and "In my clinical experience...". 

[PloskoPlus]

Sergio,

Is IMDO purely linear?  Can it be used to achieve CCW rotation?

[ArtVandelay]

Sergio, I just want to say thank you for taking time and sharing your insights here.

[GJ]

Great to see a surgeon participating in discussions. I would like to see that more often.

There are several who read here. In the past several posted.

Sergio, is there any major, active research taking place to advance distraction so it's as accurate as traditional surgery? If so, who is doing it? If not, why aren't huge research grants/funds being allocated to this? Patients would want distraction over traditional surgery. Do you think it ever becomes the gold standard, and if so, how long out is that?

[PloskoPlus]

There are several who read here. In the past several posted.

Sergio, is there any major, active research taking place to advance distraction so it's as accurate as traditional surgery? If so, who is doing it? If not, why aren't huge research grants/funds being allocated to this? Patients would want distraction over traditional surgery. Do you think it ever becomes the gold standard, and if so, how long out is that?

One surgeon I talked to told me he did quite a lot with my surgeon (of all people) about 20 years ago. He said you basically end up with multiple surgeries instead of one and it can get complicated for non-linear movements. So they reserve it for syndromal cases where movements must be huge.

[GJ]

One surgeon I talked to told me he did quite a lot with my surgeon (of all people) about 20 years ago. He said you basically end up with multiple surgeries instead of one and it can get complicated for non-linear movements. So they reserve it for syndromal cases where movements must be huge.

Yeah.
I'd like to know when that will all change and they figure out how to move in all planes with accuracy. This should be getting the majority of research money.

[Sergio-OMS]

Great to see a surgeon participating in discussions. I would like to see that more often, but I would understand surgeons don't want to post here under there actual name.

I think anybody giving medical advice should use their real name.

On the other hand, it would be great if surgeons would share their knowledge openly, online. Many surgeons could learn from eachother, i have the feeling there isn't much communication between surgeons.

I think you are probably right. Multiple reasons for that. Congresses and symposia are mainly places to show off, especially in some subspecialties where money (the future of your practice, employees, and your family) can be at stake. It is difficult to choose to really train your competitors. Besides, competitors maybe do not want to be trained, accept the protocol or they might not be skilled surgeons! Every surgeon thinks that they are better and when we learn something new we always try to adapt it to our own previous beliefs and conceptions of the problem. And materials and instruments are a problem, too. We think we can do the same technique with the sutures or instruments we already have (unless it becomes pretty obvious that it can't be done...  I mean nobody is going to do laser surgery with no laser... but might try to use another machine like a Bovie). And we don't like to be told what to do. We are always the best, always right, everybody else is wrong. This does not happen only in surgery, though... Orthodontics is even worse.

Thank you Sergio for addressing our questions and sharing your experience. Its extremely valuable to us and to the body of information available to the public regarding these procedures to have a clinician step in and clarify or explain certain concepts.  I see it as a great service to the public.

I enjoyed reading your thoughts on the topic and would encourage you to continue to contribute in any way you feel appropriate.

Thank you, I will re-read these words when I need to read them.

There's an interesting dynamic nowadays between clinical practitioners and the public due to the access to information phenomena presented by the internet (places like this board as well).   I can understand why they are generally hesitant to post.  On the public side, we have such a vast and ever-evolving body of knowledge available to us, that no clinician could ever possibly keep up with all the latest research and papers coming out of universities around the world.  On the clinician's side, they have the practical EXPERIENCE and APPLIED KNOWLEDGE which no amount of research and reading papers online could ever give.  It creates a disparity between "the research shows..." and "In my clinical experience...".

Research in surgery is very very difficult, this is not like testing a vaccine or a new drug. No control groups, no randomisation. And it is more difficult in orthognathic surgery. A lot of possible biases, orthodontists also involved.... There are way to many factors that also affect the extrapolation of the results.

Is IMDO purely linear?  Can it be used to achieve CCW rotation?

No if you mean a pure CCW in a patient with a good class I presurgical bite where the tip of the upper incisors act as the pivot point and no anterior impaction is done. IMDO is limited by the overjet.

But it can be used in the context of a CCW rotation with a Le Fort I that advances the maxilla and does a CCW by means of anterior impaction and a posterior descent, and with a curved osteotomy a posterior graft is not necessary and it's even worse to use it. But maxillary/midfacial expansion has to be done too in IMDO, remember. preop maybe? or a 2-piece Le Fort. I would probably try to go for the preop with a MARPE but its success rate diminishes with the age and becomes unpredictable in adults (over 25). But it's always possible to try, if it doesn't work then a 2-piece Le Fort along with the CCW... with CAD-CAM plates, otherwise it's too unstable.

Sergio, I just want to say thank you for taking time and sharing your insights here.

You are welcome.

Sergio, is there any major, active research taking place to advance distraction so it's as accurate as traditional surgery? If so, who is doing it? If not, why aren't huge research grants/funds being allocated to this? Patients would want distraction over traditional surgery. Do you think it ever becomes the gold standard, and if so, how long out is that?

Doing research is very difficult, very biased and a lot of times very dishonest. How many prospective patients are told that the risk of having some type of nerve damage in the mandible is 5 %? or 10 %?  Those figures are the most heard in preop consultations, and they are based on actual research...  and, to be honest.... what is the real outcome? And what does damage mean? total numbness? paraesthesia? hypoaesthesia? measured how? by the surgeon? self-reported? does everybody complain the same way?... oh, come on...


Personally, I do not like researching, I am a surgeon, not a researcher. Although the clinical data of previous IMDO patients is there, so I suppose retrospective research could be done, theoretically, but research would lead to conclusions with difficult interpretation. And with nowadays regulations about the access of clinical data, research is more and more difficult, even retrospective research.  I do not have enough experience to provide a big sample though, but I am very happy with the results on my patients,  although my IMDO patients until now are teenagers I wouldn't mind operating a young adult after what I am seeing. But it is very difficult for an adult to understand the advantages of IMDO over BSSO in large mandibular advancements, even more difficult than it is for parents to let a surgeon operate on their kid while there are orthodontists claiming that they can grow the mandible of a grown kid (mandibles do not grow much after age 12) without surgery, which is not true. They end up doing camouflage, messing with the TMJs and all to obtain an unstable and very suboptimal result.


By the way, I forgot to say that would probably describe the effects of IMDO surgery as a mandibular enlargement, not only advancement, and the full IMDO protocol as maxillomandibular enlargement.  The reason for this is that the active phase of the IMDO protocol enlarges the body of the mandible and it widens it, skeletally. It means that the upper arch must be expanded more than with a BSSO (any mandibular advancement produces a relative/false expansion, that is why upper expansion has to be done along with any mandibular advancement, even non surgical ones. And, in my opinion, it is much better if we do an upper skeletal expansion instead of a dental expansion. And even much better with MSE or other MARPE devices, because that type of expansion is a midfacial expansion compared to the maxillary expansion produced by SARPE, DOME or 2- 3 piece Le Fort.

One surgeon I talked to told me he did quite a lot with my surgeon (of all people) about 20 years ago. He said you basically end up with multiple surgeries instead of one and it can get complicated for non-linear movements. So they reserve it for syndromal cases where movements must be huge.

That was my understanding about distraction, too. I had no previous experience with mandibular distraction when I started with IMDO though 2.5 years ago, so I can't compare. But when I read the papers / books on distraction and I see photos and videos or other distraction patients I think I understand why so many things can go south...  and actually do.

Yeah.
I'd like to know when that will all change and they figure out how to move in all planes with accuracy.

There are too many factors that precludes a 100 % accuracy in any technique, and specially distraction. The reason why IMDO works really well on teens is because postop orthodontics are easier,  callus molding is easier so the surgical inaccuracy is compensated by other factors.


Mandibular enlargement is done slowly (distraction is 1 mm per day) while condyles rest in the fossae in their comfiest position, this happens in teens and adults (I do not have to place the condyle during the operation). Small midline corrections can be done... occlusal interferences happen at the end of the distraction period... then orthodontics play an important role. And yes, calluses take more time to heal in adults. Adults do not heal as fast as teenagers and the social / work life of an adult makes IMDO an uncomfortable treatment. But some adults accept these drawbacks and risks in exchange for the advantages.

By the way there are several recent research papers there on how accurate conventional orthognathic surgery is even with computer planned software, comparing the outcomes with the planned surgery (for instance,    https://www.ncbi.nlm.nih.gov/pubmed/29275075 or https://www.ncbi.nlm.nih.gov/pubmed/31034793   )  You might want to dig a little bit into it.


Let me add this, no disrespect intended... but I have got the feeling that many people in this forum think of orthognathic surgery as operating casts or 3D models. Many active users here believe 3D planning is almost a synonym of getting good results and, believe me, it is not.  Computer software is coded by humans, based on information given by other humans, and then another human will do the operation in... another human!  We do not operate x-rays or rendered images. Clinical planning is way more important than software planning.

The next step in the ladder or accuracy in orhognathic surgery is the use of CAD-CAM plates and guides. That is not computer planning, that is actual computer personalised surgery, where the planning, if done correctly, can be transferred with the highest degree of accuracy possible. But, again, we need to plan the intervention, design the plates (not every surgeons would like to use the same basic type of design and follow the same principles when designing them, or use the same grade of titanium) and then perform it... human on human. And this type of approach is veeery expensive. Interventions take longer, incisions and detachments are larger...  And large advancements or large CCWs will be always be a challenge even with this approach. Soft tissues and TMJs do not like these large movements. So IMDO can always be useful in some patients, as soft tissues adapt better to slow movements (they stretch slowly following the underlying bone)

This should be getting the majority of research money.

Let me tease you a little bit (I know you did not mean this)  don't you think there are more important fields of medicine to spend research money on? 

[april]

I've really enjoyed reading your posts Sergio! Thanks for sharing with us.

I know someone who had IMDO in their 30's.

But it can be used in the context of a CCW rotation with a Le Fort I that advances the maxilla and does a CCW by means of anterior impaction and a posterior descent, and with a curved osteotomy a posterior graft is not necessary and it's even worse to use it

Just to clarify. Are you saying that the back of the maxilla can be brought down without needing a graft? If so, is there a limit to the amount of inferior positioning that can be done without grafts?

What do you mean by a curved osteotomy? Is that like an osteotomy where some form of bone contact between the gaps is maintained?

[InvisalignOnly]

Thank you for the informative posts Sergio - I think most of us on this forum are very grateful for your input.

[GJ]

Let me tease you a little bit (I know you did not mean this)  don't you think there are more important fields of medicine to spend research money on? 

Oh, I meant research money allocated to jaw surgery. I'm not sure if any money even is allocated to it, but if it is, distraction would be a great place to put it.

[Post bimax]

Oh, I meant research money allocated to jaw surgery. I'm not sure if any money even is allocated to it, but if it is, distraction would be a great place to put it.

Lots of jaw surgeons that publish in OMS journals are also faculty at public universities, so in that sense OMS research is publicly funded.