Bill Klaproth (Host): This is AAOMS On the Go. I'm Bill Klaproth. With me is Dr. Felix Amarista, Clinical Assistant Professor in the Department of Oral and Maxillofacial Surgery at the University of Texas Health Science Center in San Antonio, as we talk about the world of custom orthognathic surgery, exploring how it has evolved from conventional methods to minimally invasive orthognathic surgery or MIOS. Dr. Amarista, welcome.

Dr. Felix Amarista: Thanks, Bill. Thanks for having me. It is truly a pleasure for me to be here with you.

Host: Well, thank you so much. I appreciate that. Looking forward to talking with you about this. So, Dr. Amarista, first off, could you share your background and what inspired you to focus on innovative treatments within orthognathic surgery?

Dr. Felix Amarista: Yes, sir, of course. I'm originally from Venezuela. I did my dental school there. Then, I had some training in Columbia, and then I was able to have the opportunity to come to the U.S. to finish my training. The reason why I've been trying to evolve and do these new techniques is basically because I'm trying to look for better outcomes for our patients and for our patients experience to be easier and easier after any kind of surgery that we do.

Host: Well, and that's a good thing too, and we appreciate you saying that. So, let me ask you this then. How does minimally invasive orthognathic surgery or MIOS differ from conventional techniques in terms of the surgical approach, patient experience, and recovery timeline?

Dr. Felix Amarista: Yes, sir. So basically, the main difference is we went from being concerned about orthognathic surgery healing in general, that was years ago, and I think we're now in a technique that we know that it works and it works really well. So basically, the next step is how do we make that same technique with smaller incisions, minimal dissection, and in general, smaller approaches in order to make our patients recover faster. So, the main difference is now we do the same thing through smaller incisions and smaller dissections. The way that I described that is it's almost like if you think about appendectomy surgery in the past or removing the appendix was used do open, and now general surgeons use laparoscopic surgery. So it's kind of like going towards that, of being less invasive when we do our procedures.

Host: And that really helps with recovery, duration, and outcomes as well. Is that right?

Dr. Felix Amarista: Yes, sir. Traditionally if you ask me, in the past, a lot of my patients, I used to tell them that they will be out of their normal life for around four, six weeks after these procedures. I've seen that now with minimally invasive, some patients one or two weeks later, they're good to go back. So, definitely yes.

Host: So, people always, I'm sure, like to hear that when you say it's less recovery time, better outcome. Probably less pain and more comfort as well?

Dr. Felix Amarista: Yes, sir. So, less swelling, less pain, less discomfort after surgery. And the main thing is, because we're doing surgery in the face when the patients are really swollen, that really affects their life because they cannot go out. Like that patient will not go to a grocery store, will not go to work, versus when we do these procedures in a minimally invasive way, they recover way faster. So, I've had patients that are two weeks later, they go back to work with no problem.

Host: Yeah, that is really good news. So, from your perspective, overlooking all of this, can you pinpoint maybe what has been the most significant advancement in orthognathic surgery in recent years?

Dr. Felix Amarista: Definitely. I think that in recent years, like I would say probably in the past 15, 10 years, has been the use of virtual surgical planning, which is we used to do all this plan in a lab with stone and we had to use our hands to do that. So even though we got good results, our ability to diagnose and do complex movement was really difficult. Now, we can plan the entire surgery, basically perform the surgery in a computer before we go to the OR. So, that for me is the biggest in the last 10, 15 years.

And then, after that, I would say in the past five years-ish, the usage of custom implants, which is one of the things that I've been using. It’s basically, while we're planning in the computer, now we have the ability to accurately transport that from the computer to the OR by designing and fabricating custom implants for our patients.

Host: Yeah, that's a couple of really big innovations here. So, let's talk a little bit more about each of those. Let's start about virtual surgical planning or VSP. Can you go a little bit more in depth on that and how that has reshaped case planning and improved precision during PSI-guided jaw surgery?

Dr. Felix Amarista: Yes, sir. So, what we do is that we obtain all the records from the patient, photos, CT scan, intraoral scans. We submit that to the company that we use for planning. And then, we get into this session with an engineer that will show us all the bones. And then we decide what movements we want based on what the patient needs.

So, the big thing in here is that in a live way, I'm performing the surgery that later I will perform in the OR. So, I have the ability to say, "Hey, move the upper jaw one millimeter forward or three millimeters forward." And in a live way, I can modify. And at the same time, because we're performing that, we have predictions of soft tissue and hard tissue bone, and where I can use as a reference to make my decision. So even though I already had a diagnosis, I can still tweak and adjust some of the little things while I'm performing the surgery on that computer.

Host: Okay. So, you talked about how VSP really helps you in case planning and improved precision during PSI or patient-specific implants – I should say jaw surgery. Can we talk about PSI little bit more then? How has that enhanced surgical efficiency, accuracy, and overall outcomes then?

Dr. Felix Amarista: In the past, before PSI exists, we used to do virtual surgical planning and then we'll use splints that were placed in the bite of the patient, in the occlusion, in the teeth in order to try to transport all that information that we had in the VSP to the OR. Now with patient-specific implants, it's way more accurate. The reason is those implants are designed custom for the patients. And they already have the information or the movement that we want for those jaws that we basically plan during our VSP. So it's the best way we have so far to basically transport or move all that information from the VSP to the actual surgery.

Host: Yeah, this is really interesting how technology has changed a lot of this. So then, let's maybe put the two together to help me understand this. So then, how feasible is the integration of patient-specific implants within minimally invasive orthognathic surgery and what adaptations are necessary for success?

Dr. Felix Amarista: Great question. And this is one of the things that I'm really passionate about. When we initially designed the patient-specific implants, the problem, let's say – or the disadvantage is – those implants were really bulky, really big. So we had to make really big incisions in our patients and a lot of dissection in order to fit them in.

When I started this journey of minimally invasive, I realized that through those smaller incisions that I was using, those big implants could not fit. So, what I've been doing is modifying those cutting guides and the patient-specific implants in order to fit those small incisions and, at the same time, be able to still do the surgery as accurate as we used to do before.

So, long story short, they have to modify the designs to make them smaller, but at the same time still be as accurate as it was before when we were using bigger implants.

Host: So obviously changes have to be made, but these are changes for the better. So then, what are some of the challenges that surgeons encounter when they transition from traditional orthognathic surgery techniques to minimally invasive methods? What are those challenges?

Dr. Felix Amarista: As you mentioned, I'm a faculty, so I train residents. So, I actually ask them a lot, and I see this a lot. Number one, you really need to know what you're doing before you want to try to do it in a smaller approach, meaning your visibility is going to be less than it was before.

Number two is about understanding the anatomy and understanding where are going to be the harder portions of the surgery. So I think that the main limitation is we're going from a surgery that the complexity is already high and to doing the same procedure, but now without a lot of visibility. So the main limitation is being able to adapt to those changes.

What I tell my residents is even though we call it minimally invasive and it has smaller incisions, my recommendation is to not just go from one day to another and to change what you're doing today to completely different tomorrow. I recommend to have this as a small, slow transition, meaning – I'm going to give you an example – if I was doing an incision from first molar to first molar, then the next day I try to do it from the second premolar to second premolar, and slowly start making it smaller.

The other part is, for the transition, I recommend to start with easy cases, and you might not know this, but there's some movements that we do that are easier than others. For example, a straightforward maxillary advancement without impaction are good cases to start evolving or start using these minimally invasive techniques.

Host: So it sounds like it's best to slowly integrate MIOS into your practice and start with the easier cases first.

Dr. Felix Amarista: Yes, sir, definitely. And then, slowly, while you get more comfortable with it, you can start doing more complex cases. At this point – and this is a question that I get all the time, and I'll tell you now – at this point, I do pretty much every single one of my cases with minimally invasive approaches, no matter how complex they are. For sure, I modify based on complexity. I might need to do the incision a little smaller or make some smaller modifications, but it is part of my practice every day right now.

Host: So, these innovations really are interesting. But again, it sounds like you really have to know traditional orthognathic surgery first before you get into this, because as you said, your vision is a little bit less when you do the MIOS. But start slow and integrate this into your practice. You know, take it as a slow process.

I'm just thinking, the innovations here are so interesting. If I could ask you to look into your crystal ball, Dr. Amarista, are there any future innovations you see coming down the line?

Dr. Felix Amarista: Definitely. I think every surgical specialty has gone through this. As I mentioned at the beginning, the main thing is we already have a technique that works really well. Now, the innovations in my mind are how we're going to make this less invasive and easier for our patients. And if you ask me at some point, we're going to be able to probably do this endoscopically, kind of like in general surgery. When you look at research now, research has gone from just looking at what the surgeons thought were good results to now looking into what we call prompts, which is patient-related outcome measures.

So basically, what that tells me is we're paying more attention to what the patients feel and how is their process after any procedure. So, I think future is going that way, how we make our patient's life easier in general.

Host: Yeah. And that is a good direction to go in. This has really been interesting, Dr. Amarista. Thank you so much for your time. Before we wrap up, any final thoughts on minimally invasive orthognathic surgery?

Dr. Felix Amarista: I think that we call this a paradigm shift. And every time we talk about big changes in any specialty, there's going to be a lot of people that are going to be reluctant to change. My final thought is the reason why we're doing this is because we want our patient's life to be better and their process to be easier after any procedure. I basically encourage any surgeon that does this and, especially the ones that are really masters, to just think about what are the things that we can do for our patient's life to be better. That's my final thought.

Host: And that is a great thought to end on. Very well said. Dr. Amarista, thank you so much for your time. I appreciate it.

Dr. Felix Amarista: Thank you so much for having me. I really enjoyed this conversation.

Host: Yeah, thank you again. And for more information, please visit AAOMS.org. That's AAOMS.org. And if you enjoyed this podcast, please share it on your social media and make sure you subscribe so you don't miss an episode. I'm Bill Klaproth. This is AAOMS On the Go. Thanks for listening.