How do we make teeth move faster?
How do we make teeth move faster?
If we all had a wish list of our hopes to improve orthodontic treatment, I am sure that one which would be close to the top would be the development of a method to make teeth move faster. I have mentioned this as one of the “great unanswered” questions in my blog of a few weeks ago. Just by chance the latest edition of the AJO-DDO has just run a supplement on surgically facilitated orthodontic tooth movement. This included a systematic review and a survey of orthodontists and patients on their perception of procedures to reduce treatment time. I would like to make this the major subject in this blog.
Over the years, we know that there have been many attempts to increase the speed that we can move teeth. These have ranged from developments in new wires, innovative bracket designs and even vibratory devices to “jiggle” teeth. Unfortunately, when each of these methods has been subject to clinical research the claims, that have been made, have not been supported by the results of the studies. It appears that bone and bone cells do not recognise the new technology. The alternative approach has been to attempt to influence the biology of the bone and this has recently led to the development of surgically facilitated tooth movement.
Surgically facilitated orthodontic treatment:A systematic review.
Eeike J Hoogeven at all
AJO-DDO 2014: 45:4 Supplement 1
This review is concerned with the use of corticotomy and dental distraction. These techniques have been developed to decrease orthodontic treatment time and to increase stability. The authors point out that these are not new techniques.
What did they do?
The review aimed to discover whether:
- Surgically facilitated orthodontic treatment increased the velocity of tooth movement
- There were any risks from this form of treatment.
They clearly stated the inclusion criteria and included RCTs, CCTs and case series with more than five patients. As a result, this was not a “classical” systematic review that only included trials. It is, therefore, important to consider the level of evidence presented in the review. It is to the authors credit that they considered this factor in the presentation of the results.
What did they find?
They identified 505 studies and after filtering for relevance and quality they finally included 18 studies. Of these, 4 were RCTs (but 3 were split mouth, see this blog post for consideration of split mouth designs). They graded these as moderate levels of evidence, all the other studies were classified as being low levels of evidence.
What did they find?
I felt that in some ways the findings were disappointing as they could not combine data from the studies. This was because of the problem of heterogeneity between the studies. This is common in many reviews, but is a characteristic of ortho studies, because we do not all measure the same outcomes in our research. Furthermore, the quality of studies were only moderate or low. As a result, their conclusions were very provisional and represented a high level of uncertainty.
In summary, it appears that corticotomy facilitated orthodontic treatment may temporarily enhance the speed of tooth movement, but this was not consistent. Importantly, no evidence of harms was detected. While these results seem promising, there is a clear need to carry out more high quality research. We are not in a position to be certain that this treatment works.
Uribe F et al
AJO-DDO 2014, 145: 4: supplement 1
The aim of this survey was to gather the perception of orthodontists and patients/parents on the use of additional procedures to reduce treatment time. The survey was sent to 9160 members of the AAO by web delivery and collection. They also approached the patients and parents who attended two practices to take part in a similar survey.
What did they find?
Unfortunately, the response rate for the orthodontists was only 665 responses. This is very low and I doubt that these findings have much validity. They got full responses from 50 adult patients, 200 adolescent patients and 200 parents. However, I could not find any information on the number that they approached to take part in the study.
As there are issues with the validity of the orthodontist sample and parent/patient impressions are probably more important than clinicians, I decided to concentrate on the patient/parent data.
Nevertheless, they concluded that patients would like to see a reduction in the overall time of their treatment and hoped that treatment would last between 6 and 18 months. When asked about their preferences for methods to reduce the treatment time, it was not surprising that they opted for non surgical methods. They definitely did not like the idea of corticotomies!
What did I think?
My interpretation of the review was that there may be something to these techniques, (I also concluded this when I reviewed a paper on this a few months ago, this can be found here). I thought that the survey was very useful because it was clear that, if we are to provide this treatment, we need to take into account patient opinion. It was no surprise that they were not keen on invasive procedure and would prefer other methods. However, this does give researchers the opportunity to carry out a project into patient preferences for different methods as a “trade off” for various reductions in treatment time. For example, would a patient undergo corticotomies for a reduction in treatment of 6 monte or one year? While this opens up a path to some fascinating and important research, the important factor missing in my discussion is that “we do not know if any of these methods actually work”…as a result any work on patient preferences is only hypothetical.
If I try and put all this together. My feeling is that I really doubt whether the solution to reducing treatment time will be found by developments in materials. The way forwards is surely to consider the biology of tooth movement and this may be done by the techniques outlined in this review, or by the use of vibratory devices, which do have a theoretical basis. At present, we only have small-scale studies in surgically assisted treatment and in the case of vibratory devices, absolutely no clinical trials. Therefore, research is clearly necessary.
This then brings us to another problem and I cannot help feeling that the specialty needs to learn from the widespread adoption of self ligation in the absence of evidence and not use these methods until they have been evaluated in scientific studies. This is our newest ethical dilemma. I will wait for the research to be carried out, but how many other people will do this? The advertising has already started…..
Hoogeveen, E., Jansma, J., & Ren, Y. (2014). Surgically facilitated orthodontic treatment: A systematic review American Journal of Orthodontics and Dentofacial Orthopedics, 145 (4) DOI: 10.1016/j.ajodo.2013.11.019
Uribe, F., Padala, S., Allareddy, V., & Nanda, R. (2014). Patients’, parents’, and orthodontists’ perceptions of the need for and costs of additional procedures to reduce treatment time American Journal of Orthodontics and Dentofacial Orthopedics, 145 (4) DOI: 10.1016/j.ajodo.2013.12.015
Emeritus Professor of Orthodontics, University of Manchester, UK.