Wednesday, 27 December 2017

Vibration does not speed up extraction space closure

I have blogged previously on appliances claiming to accelerate tooth movement and shorten orthodontic treatment. One of these is micro-vibration and an appliance using this principal is AcceleDent. I have previously researched this topic during initial alignment and now Part 2 has been published on extraction space closure.

I strongly believe in an evidence-supported approach to clinical practice and this study (as with all my research) was conducted in my orthodontic practice to answer the clinical question of whether this was a worthwhile technique to consider implementing for my own patients. Forty Class II adolescent patients planned to have premolar extractions in the upper arch were randomly assigned to using either the AcceleDent appliance or no appliance. The extraction space closure was measured over time so a rate of movement in mm/month could be calculated. So what did I find? There was no clinically (0.05 mm per month) or statistically significant difference in the rate of space closure (P = 0.74). Compliance was found to reduce over time and this is the subject of another paper to be published in the Journal of Clinical Orthodontics. However, even when compliance was accounted for there was still no clinically meaningful difference in the rate of space closure.

This article appears in the American Journal of Orthodontics and Dentofacial Orthopedics and anyone clicking on this link before February 14, 2018 will be taken directly to the final version of my article on ScienceDirect. No sign up, registration or fees are required – you can simply click, read and hopefully enjoy.

Tuesday, 5 September 2017

Digitally positioned brackets - are they any better?

In orthodontics, the current trend is to find ways to accelerate treatment with many appliances making these claims, even in the naming of their appliance or technique (Fast, Quick, Rapid, Speed, 6-month, etc.). There is substantial evidence now to demonstrate that simply changing to a different type of bracket makes no difference – it is the skill of the operator that is most important, otherwise the patient may be accepting a compromise. For example; if treating only in round wires then the roots are not rotated, tipped or especially torqued into their best and most stable positions or the occlusion or overjet not addressed.

To overcome this, some companies have suggested that digitally positioned brackets are the answer as they reduce variability and take into account a lot of the skill and variation of the operator. Systems such as Insignia, SureSmile and even Invisalign are examples of these in orthodontics. However, there is a lot of biological variation with individual patients varying in response as well as appliances do not deliver 100% of what is built into them which is why detailing/finishing is required (the fiddly part of orthodontics). Previous retrospective studies have suggested that digitally customised appliances did deliver faster treatment but these had the same flaws as the self-ligating bracket and vibration appliance studies in that there is a high risk of bias and potential confounding variables that can influence the result beyond just the appliance (the later RCTs found no difference). This is why blinded, RCT’s are considered the gold standard – but also take more time and cost to conduct. However, an RCT was just published online in the Journal of Dental Research (considered the top journal in dentistry in terms of the quality of the articles) and this paper looked at the Insignia system of digitally positioned brackets compared with conventional placement. The results were interesting!

There were 180 patients in this RCT and when completed, they analysed 85 patients in the customized group and 89 in the non-customized group. The authors found no difference in treatment duration (digital = 1.3 years vs. conventional = 1.2 years) or quality of outcome as measured by the PAR (Peer Assessment Rating) index. Most importantly, the Orthodontist did have a significant effect on treatment duration, quality of treatment outcome, and number of visits (P < 0.05) - not the appliance used. Interestingly, the customized orthodontic group also had more loose brackets, a longer planning time, and more complaints (P < 0.05).

In the rush (pardon the pun) for faster treatment and to seem to be on the cutting edge, we can leap into new technologies. Sometimes they deliver what they claim while at other times they do not. Such systems usually involve additional cost with an expectation by the patient of faster treatment but in this case, it wasn’t delivering what it claimed. Some practitioners may prefer these systems and that is a personal choice just as some prefer one bracket type over another, but when claims are made of a faster or better outcome (and often at added cost)… proof rather than opinion is required. As Carl Sagan (Astrophysicist) famously stated; ‘Extraordinary claims require extraordinary evidence’.

Wednesday, 10 May 2017

Fast Orthodontics - In Search of the Holy Grail

I recently wrote a review article in the Australian Dental Journal supplemental issue on accelerated orthodontic treatment. In it I discuss the many claims by manufacturers of several appliances and proponents of various techniques that claim to accelerate treatment. This appeals to both the patient’s and the clinician’s desire to ‘speed’ up and shorten their treatment, however how strong is the evidence or is it just marketing hype? I am a little concerned as it would appear that in some respects, advertising claims in orthodontics are following down the path of the exercise fads claiming rapid results with little or no effort - I certainly find some effort and restraint is required :-). Mechanically and biologically, many of the claims of accelerating orthodontic treatment just do not make sense (such as with self-ligating brackets which I have written about before) or are quite invasive and/or expensive (some of the surgical techniques are ~$5000 and the effect lasts only ~3 months). This is discussed in more detail in the article.

One of the clinical trials I have been conducting in our office on vibration and accelerated treatment was also published recently in the American Journal of Orthodontics and Dentofacial Orthopedics and I was asked to produce a short video on that article which can be found here.

This was included in the review article I wrote also. More recently we have just analysed the data on the 2nd part of this ongoing RCT when closing extraction spaces and I also found that there was no clinically or statistically significant difference in the rate of space closure – in other words, vibration had no effect. This is important for patient’s to be aware of as they can be asked to spend $500 - $1000 for various appliances which may have minimal or no effect. The problem with emerging techniques and methodologies is that there may be no trials examining their performance so we must then rely on our knowledge of biology and mechanics on whether we consider it ‘may’ have a positive effect or not. However, if we are unsure, then patient’s should be informed of this until research exists. They can then decide if they will gamble on the appliance/technique possibly working or stay with the current approach. So the Holy Grail of accelerated orthodontic treatment seems elusive and the honest answer about the various options to patients is ”There are many techniques and appliances claiming to accelerate orthodontic treatment but the current evidence is poor and some have been shown to have no effect”.