Kevin O'Brien: What do I know about clear aligner treatment?

Clear aligner treatment has been used in various forms since 1945.  Following the development of Invisalign there has been a remarkable increase in aligner treatment. Aligners are used increasingly by providers of varying experience levels. Furthermore, there maybe a perception that they are easy to use. This might be a strength from a marketing perspective but could perhaps also be the undoing of these systems? Finally, there are significant developments and the introduction of new treatment methods nearly every year, which makes research difficult.

As a result, it is perhaps no surprise that there is little research done into the effectiveness of aligners. Indeed, in about 2003, Bill Shaw and I met with Invisalign to discuss carrying out trials. They were not keen on the level of research that we wanted to do, but they gave us some nice bottles of Californian red wine for our time.

What do I think?

Many years have passed since that meeting. So, I thought I would set out the main points of my understanding of CAT from the literature that I have reviewed in my past blog posts and some personal comments.

• The overall accuracy of treatment relative to predictions is only 50%
• We don’t know how effective aligners are at correcting Class II problems
• The standard of treatment with Invisalign for mild malocclusions is high
• Invisalign treatment takes longer than braces
• We still don’t know if Invisalign Mandibular advancement is effective
• With clear aligner therapy, most tooth movements may not be predictable except for minor horizontal tooth movement.
• We don’t know if aligners result in less root resorption than fixed braces
• Patients don’t like multiple attachments
• There is not much evidence to support the 7-day aligner change protocol
• May clear aligners be harmful to the Worlds environment?
• I don’t understand why some orthodontists post pictures of themselves with piles of aligner boxes.
• Why do people look at their ClinChecks by the swimming pool or in lectures?
• Why does everyone appear to be a top 1% provider?

Summary

In summary, the research that has been published suggests that clear aligner treatment is effective for treating minor malocclusions. However,  I cannot help thinking that fixed appliances are still the most effective treatment method for most cases. Nevetheless, hybrid approaches also exist in some instances, particularly where aligners may struggle to deal with more complex tooth movements predictably.

A bit of retrospection

My final comments are my own perception of looking at completed aligner cases on social media, KOL posts, and aligner company websites. While some operators show excellent cases, others are not so good and don’t look as though they are finished properly.

UK orthodontics 40 years ago was not high quality because most treatments were provided with simple removable appliances that tipped teeth. I am not sure that aligner results are dramatically different. If I quote a catchphrase from an aligner KOL. “I can’t do that with braces” I agree; “I can often do a better job with braces”.

Finally, perhaps, an “untidy finish” is the trade-off for invisible appliances? Or am I just a cynical retired ivory tower Professor? Let’s have a heated discussion.