At last, a large study on orthotropics: The first nail in the coffin?
Over the past few years. I have posted several times about orthotropics. This is treatment was invented by Joh Mew in the UK. It is based on the concept that using removable appliances can change the skeletal pattern and muscle function. Unfortunately, while John and, more recently, his son Mike has vigorously promoted orthotropics, high-quality research has not been done on the effects of treatment. Until now, when I came across a well-written MSc thesis from the University of Alberta.
What is orthotropics?
I posted about myofunctional orthodontics and orthotropics in 2015. However, some readers may not be familiar with this treatment. Therefore, I have done a quick, precise
This form of treatment was developed by John Mew in London, South of England. Over the last 20 years I have had discussions with John about this treatment. He has given a seminar to the speciality trainees at Manchester. However, UK orthodontics has not accepted his thoughts and there may be many reasons for this. I do not want to go into them now. However, his son Mike, a speciality-trained orthodontist has joined him and these ideas are being put forward more concisely. Details of this treatment are on their website.
In brief, orthotropics is based on the theory that different forms of removable appliances and relevant muscle training correct the soft tissue behaviour and oral environment. This then results in the development of the skeletal bases and a change in the position of the teeth. I have looked at the evidence that has been published. Unfortunately, I could not find any sufficiently powered prospective studies. They illustrate successfully treated cases in papers, a published book and on their website. However, some of these look a little dated. This is reasonable because John has been working as a single-handed practitioner for many years with limited resources. Nevertheless, there is no doubt that some of the results are impressive.
The first large study on orthotropics
A team from Alberta, Canada did the study. The University of Alberta published the thesis in its depository.
Skeletal and Dental Changes from a Compliance-Based Orthotropic Treatment Approach with Exercises to Improve Orofacial Posture.
Lead author: Faraz Tavoossi. Supervisor: Manuel Lagravere. Committee Member: Carlos Flores-Mir
What did they ask?
They did the study to:
“ Investigate the skeletal and dental changes that occur using a compliance-based orthotropic treatment approach with orofacial posture exercises aimed at controlling vertical facial skeletal growth in the mixed dentition”.
What did they do?
They did a retrospective investigation.
They analysed the cephalometric radiographs of 102 consecutively treated patients. A general dental practitioner (Dr Wong) treated the patients using the standard orthotropics two-phase approach. His initial phase of treatment was directed at the expansion of the arches using removable appliances and a series of daily exercises that were directed at improving oral posture. The second phase of treatment was done with the Mew Biobloc appliance to train the patients to adopt a closed-mouth posture at rest.
Dr Wong took cephalograms before and after active treatment.
They compared these cases to a ‘Control’ group. This was 75 sets of records obtained from the AAOF Craniofacial Growth Legacy. They matched the patients for age sex and timing of records.
The primary outcome measure was the change in 13 skeletal and dental measurements.
What did they find?
The mean age of the patients at the start of treatment was 8.4 years (range 5.5-11.75). The mean length of treatment was 4.1 years (range 1.6-7.00).
They confined the results of treatment to cephalometric measurements. I will not present and discuss all these here. But these were the main points.
They found the following when they compared the two groups pre-treatment measurements.
- Most of the dental and skeletal measurements were not statistically different.
- The treatment group had a 6.6mm shorter mandibular body length than the control group.
- The treatment group had a 5.4mm shorter initial facial height and 1.39mm shorter ramus height than the control group.
These are clinically significant differences. As a result, we need to consider these differences when we critically review their findings.
When they looked at the effects of treatment, they measured change. These were the important, statistically significant measurements.
- SNA increased by 0.97 degrees in the treatment group but decreased by 0.13 degrees in the control group. This resulted in a difference of 1.09 degrees.
- ANB decreased in both groups, but this was greater by 1.47 degrees in the control.
- Mandibular body length increased in both groups by approximately 8mm.
- There was a statistically different difference in gonial angle reduction. The control group was reduced by 1.2 degrees more than the treatment group.
- The treatment group had a 1.6mm less increase than the control for lower facial heights.
- In the treatment group, the upper incisors proclined 8.5 degrees more than the control. Similarly, the lower incisors were proclined 4.8 degrees more than the control group.
- The treatment group had 1.2mm less overjet and 1.2mm less overbite than the control.
I have interpreted this data as suggesting that the appliances did not change the skeletal pattern of the patients in a clinically meaningful way. Furthermore, they appeared to simply procline the upper and lower incisors.
The authors of the thesis concluded:
“The treatment protocol may not be considered to have produced a clinically meaningful effect on skeletal and dental changes”.
What did I think?
I have looked at many Master theses during my career, and this was one of the better ones. All aspects of the work were well written.
I would also like to acknowledge the work that the dentist, Simon Wong did in collecting these records. Furthermore, he took the step of submitting his records for research. This was in marked difference to John and Mike Mew, who have not subjected such a large sample of cephalometric records for analysis.
I want to congratulate him on his contribution to research in orthotropics. Before Simon submitted these records to Alberta, he had offered to submit them to me for analysis. Unfortunately, I could not do this because I had stopped working in the Dental School and had no access to resources. However, he was encouraged and decided to work with Alberta.
However, we must remember that this is an unpublished Masters thesis. As you know, I do not usually review these. I decided to take this step because the work dealt with a controversial area relevant to our clinical practice. Importantly, I understand that the authors submit will submit these results and others for publication in a refereed journal.
I have looked at this as if I were refereeing a submitted paper. While this is a good piece of research. There are some issues that we need to consider.
- It was a retrospective study and is subject to selection bias.
- The control group was taken from a growth study and is therefore subject to secular change.
- The outcome was confined to cephalometric data, and other outcomes need examining.
Nevertheless, this is an excellent first step, but we must carefully consider the uncertainty these issues introduce.
In summary, this thesis suggests that the orthotropics approach does little. Importantly, It does not influence the skeletal pattern differently from any other functional appliance treatment or even just normal facial growth. All it does is procline the incisors. Notably, this data does not support any of the Mews’ claims for orthotropics.
I know there will be a load of moans and gnashing of teeth from the orthotropic/myofunctional believers. Nevertheless, this is the first research into this treatment. I would like to say that If you really believe in your treatment, why not be as open-minded as Simon Wong and research its effects?
Emeritus Professor of Orthodontics, University of Manchester, UK.
Have your say!
MMM, We have a dedicated general dentist Orthotropist in our area with a committed following. While, on one level, he is providing a valuable social service by keeping the “nutty parents” away from our practice, we are having an increasing number of patients coming in who have had years of treatment, are burnt out, and still have the orthodontic issues they started with. The one thing I can’t work out (although, to be truthful I haven’t really investigated the techniques of orthotropics) is the increased overjets from the start of treatment. Some of these are quite spectacular (8-13mm in one case). The parents get a bit of a shock when I explain about natural growth and orthodontic effects of growth (you can’t make arms grow, you can’t make legs grow, you can’t make jaws grow- well maybe a small amount). Unfortunately many have already been ideologically indoctrinated with the orthotropics mantra and can’t believe they’ve been treated with quackery. The upside- they haven’t really drunk the koolade. Apart from a large bill (because the orthotropics treatment is so special and so more expensive than conventional treatment) and not being keen on further treatment because they are burnt out, no major harm done.
Any ideas on the increased overjets greatly appreciated.
The initial appliance proclines the upper incisors as it expands the arch. Perhaps you are seeing patients at the end of this phase? Just a thought as I am not an expert in this arena, but in the midst of doing a deep dive into it. This article came at a perfect time.
Quoting from this blog, “I would like to say that If you really believe in your treatment, why not be as open-minded as Simon Wong and research its effects?” While waiting for a response from “The Mews”, my expectation is that scholarly endeavors will continue to be seen as an annoyance to the orderly flow of both ego and commerce.
Long time no see and I agree with you!
Afterall, as a clinician, I want to look at the numbers and research systematically, and not just case reports.
Dear Prof O’Brien,
Thank you for your interest in my work and our study, which is ongoing. Your comments are appreciated and strike a cord that resonates with ours.
As the initial timeline study was until the pubertal growth period only, and the cephalometric measurements didn’t not explain the photographic clinically positive outcomes seen in the teenage year follow up’s, more analysis was commenced last year. The cohort I presented are of 152 consecutively started cases of severely skeletally compromised growing children and as clinically my treatment appeared most beneficial in the outcomes, the university faculty approved the retrospective study.
In the cohort for example were selected 50 cephalometricly confirmed hyperdivergent growers to be further evaluated separately over a longer timeline.
At the time of the initial study commenced in 2020 we had only good metrics for 4 year period. Over the last 3 years since, I noted positive changes clinically in the incisor position and dental alignment so continued to follow up with 6 and 8 year cephs. These are now in analysis and we look forward to revealing this findings for publication in the future.
I am a firm advocate of the scientific process and seek the truth, where ever it may lead.
Incredible for you to share this database Simon. Well done! Is there a place to review some of the patients before and currents along with mechanotherapy used?
Sorry for the delay. I would like to thank you again for collecting and sending these records to Alberta. It really is an open minded approach to this treatment. I look forward to seeing other results as they become available.
Thanks, Simon, for sharing your cases.
We need more clinicians with unique ways to manage cases to be open to quantifying what happens in those cases.
A research team led by Peter Buschang will soon present their analysis of the most hyperdivergent cases. I look forward to seeing what is reported in that subsample with a different methodological approach.
It would be invaluable if there was a way to obtain another control group. This control group would have the same starting skeletal and dental parameters but not treatment. It would add great value to the study.
Thanks for making your records availible for study. Do you have any estimate for when the next study long time study will be released?
I agree with that. It seems the orthotropic treatment did make the patients grow similar to a healty person that did not need treatment. But how would the patient have grown if they did not receive treatment? I suppose it would be hard to find such a control group that receive no treatment.
Dear Dr. Vendittelli
Given recently published data, largely derived from controlled observational studies, regarding various improved health indicators (e.g., QOL, general health and decreased naso-respiratory resistance, etc.) often associated with rapid maxillary expansion treatment for pediatric patients diagnosed with maxillary transverse deficiency (i.e., ‘…the starting skeletal and dental parameters…’ ), would not the deliberate withholding of dentofacial orthopedic treatments (e.g., orthotropics, RPE, etc.) for the sole purpose of establishing a control cohort be considered unethical?
This is an interesting study but the findings are not entirely unexpected. In an early study (1), I looked at upper airway changes with Biobloc, which appeared promising, but my follow-up study on this topic (2) found changes with Biobloc were about the same as findings with conventional treatment. Around that time, I had mentioned to John and Mike that the term ‘orthotropics’ is a conflict of terms (since ortho = straight, and tropic = bending), while the term for ‘unbending’ in the literature is ‘orthocephalization’. I believe the term originated with John equating facial growth with natural phenomenon (such as heliotropism in plants). I had also suggested that they might consider “orthotrophics” (with an h) since ‘trophy’ relates to growth such as hypertrophy, while ‘tropy’ relates to bending, such as anisotropy. I guess it’s a moot point at this stage but no 3D data has been investigated in statistical shape-space as yet and the reliance on 2D cephalometry remains untenable (3).
1. Singh GD, García AV, Hang WM. Evaluation of the posterior airway space following Biobloc therapy: Geometric morphometrics. Cranio 25(2): 84-89, 2007.
2. Singh GD, Medina LE, Hang WM. Soft tissue facial changes using Biobloc appliances: geometric morphometrics. Int J Orthod. 2009;20(2):29-34.
3. Bookstein FL. Reconsidering “The inappropriateness of conventional cephalometrics”. Am J Orthod Dentofacial Orthop. 2016;149(6):784-97.
Wonderful objective and open-minded review even complimenting the results you have seen in case studies!
I sometimes think that it’s easy to forget that there’s a patient attached to the brace. 4 years mean treatment time! We should make our treatments as short as possible, not as long as possible; braces are not a joy to wear. Over the years I’ve seen a few orthotropic transfers that have been expanded into complete bilateral scissors bite and have then stuck there when they should just have had extractions.