Why would an orthodontist or an orthodontic patient consider treatment with clear aligners in the mixed dentition? My thoughts center around the same premise why adults and teens are offered aligner therapy: for a more comfortable patient experience. While the orthodontic world is full of appliances used for Phase I treatment, aligner therapy is finding a place in this age. Invisalign is already in the process of tailoring their product to function more seamlessly for interceptive treatment, but the extended refinement period on approved cases has opened the doors for most practices to start offering this option.
For any of you considering integrating aligners into a Phase I treatment plan, you should take into account a few factors that will make your experience, as well as the patients, the most positive it can be. First being the purpose and objectives of your Phase I treatment. Since patients are often in the early mixed dentition, the treatment should be focused on the limited goals. Ordering several sets of additional aligners can easily prolong treatment when managing erupting teeth. Keep the goals and limits very clear to avoid getting sucked into multiple and excessive refinements.
Second, the clinical crowns in the mixed dentition are short, so beware. Short clinical crowns in aligner treatment can spell fit and retention issues, if not managed properly. To address this challenge, add many more of attachments for retention. I add attachments on the primary molars and try to avoid the primary canines since their loosening can cause issues with fit.
Third, beware of erupting teeth. We have had a few patients where we scanned and by the time the aligners came, they wouldn’t fit! Whenever possible, I have been more selective with cases that are in a less transient mixed dentition where the four incisors have erupted and you have several months before any more primary teeth erupt. Remember that eruption tabs are quite specific and more designed for late mixed dentition cases. When incisors have not erupted, or even first premolars, I find I was chasing the case until I could scan again and again. Therefore, be selective in timing of cases. Also be creative using pontics where eruption tabs are not available. The advantage of the developing and erupting dentition, is that once space is opened, teeth will erupt into place and commonly drift into pontic spaces or eruption tabs. These are advantages in an aligner system, compared to the obstruction brackets bonded on exfoliating primary teeth.
Phase I Features
There are also some additional features in the pipeline that are well suited for early treatment. These include pending features such as a Phase I aligner product, an expansion appliance in the works, and the MFA appliance that will facilitate Class II correction.
Despite some potential challenges, and many young patients requesting colors for treatment, proper case selection in Phase I aligner cases can lead to success. Aligners for young patients can offer another great option that was not available before. Knowing these potential challenges and proper preparation for these treatment plans can offer the same advantages teens and adults experience while in the early mixed dentition.