Appliances and ligation: what’s best for oral hygiene?

Orthodontists tell us all the time that that their patients, or more usually their patients’ parents, fret about keeping teeth clean during the course of orthodontic treatment.

They worry that food will get trapped in the appliances, and there will be a long-term increase in likelihood of dental caries and gingivitis, and they ask if there isn’t a way to minimize all of this by choosing the appliance judiciously. Sometimes they’re very well read, and they even know about trends in anti-microbial adhesives.

In choosing the best appliance, with oral hygiene in mind, they think, and orthodontists often think, that clear aligners, and self-ligated brackets, are better than the usual fixed appliance system.

Is this actually true?

A very interesting article just appeared in the American Journal of Orthodontics and Dentofacial Orthopedics about this. What they found surprised even us.

Investigators undertook a 3-arm trial of the long- and short-term hygiene outcomes in 71 boys and girls randomized for clear aligners, preadjusted edgewise fixed appliances with self-ligated brackets, or traditional preadjusted edgewise fixed appliances with elastomeric ligated brackets.

The primary outcome was plaque index, and the secondary outcomes were gingival index and periodontal bleeding. Assessments were at beginning of treatment, 9 months, and 18 months.

They found very similar means and standard deviations in plaque indices. In gingival index and periodontal bleeding they found only mild significance in odds ratios (p=0.015 and 0.012, respectively).

There was no evidence of real difference in oral hygiene among clear aligners, self-ligated brackets, and conventional elastomeric brackets.

We confess that we were surprised.

Should we have been?

We went looking for more research, and found a recent systematic Cochrane database review and meta-analysis of the effect of bracket ligation on adolescent periodontal status.

The results? There was no evidence supporting self-ligating or conventional steel ligated brackets. Where endpoints were plaque and gingival index, differences existed but they were non-significant overall.

Which system you choose for your patients, in other words, needn’t be a source of concern when it comes to periodontal health. Have a look at what we have, by way of fixed appliances and various elastomeric products, and see what you think. Get in touch if you have any questions. Chances are, we’ve done the reading, and we have an answer!