Riparazione della radice dentale con gli ultrasuoni. Conferenza del dott. Tarek El-Bialy, Ortodonzia e Bioingegneria, Università di Alberta
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00:00Good morning everyone. Thanks for David and Kevin for inviting me to present and
00:06share with you my discovery and how we are moving from accidental discovery in
00:12the lab to advice that can save millions of people's teeth around the world. So
00:19this is myself. I work at University of Alberta in orthodontics and also I hold
00:24I'm a private practitioner and outside I have a private office and also I have a
00:31PhD in bioengineering. In 2006 there was a huge media release in mental
00:40researchers patent new technologies that can regrow teeth and hopefully in a few
00:46years we can reach that claim. But a device that can help you grow your own
00:52teeth. Broca tooth growth back. So this is true. I'll share with you what we have
01:00and where we are and the future. Okay so this is the accidental discovery in
01:08dental research. Basically if you are familiar what's distraction isogenesis
01:13or surgical bone lengthening. So if someone has a short bone like this girl
01:19for example this this leg is short. So what they do to lengthen this short leg
01:24they cut it put a screw in it and then they open the screw every day and then
01:29in a few months the short leg can be as long as the normal leg. Okay in cranial
01:35facial area we are dealing with lots of problems especially with the lower jaw.
01:38When the lower jaw is underdeveloped like this we can do the same thing the
01:42same technique. We break the jaw put a fixator with a screw in place and then
01:47after a few weeks then the patient move from here to here. And basically the
01:53whole idea is to regenerate or grow the patient's own new bone without the need
01:58for any hip or any bone graft or any other materials. The only problem with
02:03this technique in the cranial facial area usually we hope to get the bone
02:08from here to here but most of the time the bone doesn't grow in the direction
02:12that we have. And most of the time it grow in different directions and the
02:16output or the resultant bone shape is not what we are actually planned for. So
02:21we try to look into something that can promote the bone healing at this
02:26distraction site or at the bone fracture site. So we looked at different
02:32non-invasive techniques and ultrasound was the best one that or best solution
02:38that's been used in clinical trials and in the lab for almost 30 years to
02:43promote fracture healing or bone to help healing of fractured bone. So we
02:50have three types of ultrasound just to introduce you briefly what ultrasound
02:54because lots of people get confused about the sonar that's been used and and
02:58the shockwaves. So there are three types of ultrasound depends on the power. The
03:03shockwaves that can use diagnostic sorry that's this diagnostic that lots of
03:08pregnant women can use to check their babies and operative that can
03:13crush kidney or renal stones and it has lots of power. And the therapeutic one
03:17that's mainly used in physiotherapy and this is the one that we are going to
03:21talk about its application in dentistry today. So the first research that I did
03:29was at University of Illinois and that was my PhD was to evaluate and
03:34commercially available ultrasound device that's been used to help healing of
03:38fractured bone on bone maturation during mandibular or lower jaw
03:43distraction osteogenesis or lower jaw surgical lengthening. As you can see in
03:47this rabbit here we cut the lower jaw we start to lengthen or open the screw and
03:51then we hope only new bone to be filled in this space here. And this is where the
03:57cut was and when I did the cut I cut the lower incisor as well and we were really
04:03excited to see what's going to happen to that lower incisor. And then after a few
04:09days you can see the side that treated by ultrasound the tooth was growing more
04:13than the other side. And that was a big discovery and I got lots of criticism
04:18from my supervisor what did you do to this poor rabbit nobody will believe you
04:23you will present this in improper research book and lots of funny stuff.
04:29And then until four weeks after this discovery we did the histology and then
04:35this is the new bone that you can see here and in the middle of the gap we had
04:40a new tissue that it's not bone. And on a higher microscopic level you can see or
04:45if you're an expert in the dental field this is new tooth that's been formed at
04:50this destruction site. That was the first time in history that we can show people
04:55that new dental tissue can be formed in a few days. Again rabbit's teeth are
05:00different slightly from human teeth. So there was lots of criticism how to
05:06apply this into a clinical trial or in human. So basically the results of this
05:13research that ultrasound can generate new dental tissue formation
05:18and this new dental tissue formation is dentin and dentin basically it makes the
05:22bulk of the tooth and cementum which is the outer layer that attach the roots of
05:27the teeth to the bone. So these two main parts can be regenerated by
05:32ultrasound in rabbits not the enamel yet because the enamel is a different story.
05:37So in orthodontics when we move teeth there are lots of risk factors that a big
05:44chunk of people can get into big problem that's unresolved at this moment which
05:48is root resorption or root shortening. So when you have braces for three to
05:53three or four years if you are one of those high-risk patients what can
05:58happen the roots can be gone like this. So there is no roots so the tooth can
06:03start like this and then after three four years the root has been blunted and
06:08shortened get shortened. This is a real case that's been sent to me on daily
06:12basis one of the cases. And also on other patients from UK all over the world they
06:20have this problem and there is no treatment for those patients so far. So
06:25we started a clinical trial pilot clinical trial on patients that they
06:29have braces and in some patients that they are going to have braces some of
06:33them we have to take some teeth so we can have spaces so we can straight up
06:37their crooked teeth. On those patients the teeth that to be extracted are always
06:42good candidates for us to do some research on them because the patients
06:45are going to lose them anyways right. So yeah but we had also had a hard time
06:51recruiting patients because most of them they are excited to get into a braces
06:54we want to finish the braces so and so anyways so we're successful in getting
06:57some patients and we start to apply some forces to induce root erosion or root
07:03resorption. And on the other side in each patient we apply the commercially
07:07available ultrasound device. You can see the applicator here is big as big
07:12like a Tony and it wasn't actually comfortable for the patients to apply it
07:17but I was lucky to get really good patients or compliant patients to use
07:21this commercially available device. After four weeks the teeth that didn't
07:26receive ultrasound you can see the erosion this is the cementum layer here
07:30and also the dentin get eroded and this root as well you can see the erosion
07:35everywhere but interestingly after four weeks when we apply the ultrasound here
07:40new dental tissue was formed new dentin and new cementum that was again the
07:46first time in history that we can show that new dental tissue can be formed in
07:50four weeks and that was published in American Journal of Orthorhontics. So we start to
07:56move more higher to higher forces because when we did this pilot study we
08:01were aware like we were actually we had to be very careful not to apply
08:05too much force so the patient don't get a severe pain and stuff. Now we're
08:10confident enough to apply huge amount of force and see what in the real life
08:14what's going to happen. So this is what happened. This is at University of Alberta
08:19a patient came for the same experiment and then we apply huge amount of force
08:23like almost 13 times the original force that we applied. Just try to imitate the
08:29real-time or the real-life orthorhontic force application and then when we apply
08:34ultrasound to this site only you can see the root was preserved here but the
08:38inside root was severely resorbed and the control root or the tooth that's
08:43been moved without any ultrasound the two roots get shorter compared to the
08:47preserved root here. So that means the ultrasound really works. So we have lots
08:54of patients that been send us emails for photographs of their x-rays photos on
09:00daily basis. We try to save the roots so you can see millions of patients
09:04worldwide they have these problems.