Over the past few years, I have observed the increasing adoption of clear aligner therapy for treating growing children and mixed dentition cases. While traditional fixed appliances remain the gold standard for many early interventions, clear aligners offer unique advantages, making them an appealing option for certain patients and treatment goals. In this post, I’ll review the current state of clear aligner therapy in mixed dentition, discussing critical elements for success.
Opportunities
Clear aligners provide several potential benefits for young patients. Multiple studies have found that patients using clear aligners demonstrate better oral hygiene and periodontal health compared to those with fixed appliances [4]. Better hygiene is particularly valuable for children struggling with brushing and flossing around brackets and wires. Clear aligners are often reported to be more comfortable than fixed appliances and are nearly invisible, which can boost confidence and compliance in image-conscious young patients [4]. Clear aligner patients typically require fewer emergency appointments without brackets or wires to break, reducing disruptions to school and family schedules. The ability to design “eruption compensation” into aligner plans allows for continued tooth movement even as new teeth erupt into the arch [2].
Limitations and Challenges
Despite these advantages, clear aligners have some critical limitations in mixed dentition treatment. Clear aligners are effective at dentoalveolar expansion but require other appliances to achieve skeletal expansion or growth modification. While some studies suggest that younger patients are more compliant with removable appliances, treatment success still heavily depends on consistent wear. Specific tooth movements remain challenging with clear aligners. The shorter clinical crowns and erupting dentition can create some challenges in treatment. Proper timing of treatment and attachments for retention can help with these challenges.
Force Systems for Predictable Transverse Changes
Achieving predictable transverse changes with clear aligners requires careful attention to force systems. Plan for mesial-out rotation of molars to achieve some arch width increase without excessive buccal tipping [3]. Utilize a sequential expansion protocol, starting with posterior teeth and progressing anteriorly [1]. Molar first expansion staging can benefit certain cases needing significant transverse improvement. Build in slight overcorrection of transverse movements to account for potential relapse. Use optimized attachments on posterior teeth to enhance control and reduce unwanted tipping [1]. For cases requiring significant expansion, consider using a palatal expander prior to or in conjunction with clear aligner therapy.
Conclusion
Clear aligner therapy offers an alternative to fixed appliances for treating growing children in mixed dentition. Aligners can effectively address a range of malocclusions while providing hygiene, comfort, and aesthetic benefits. As with any treatment modality, success depends on proper case selection, realistic treatment planning, and close monitoring throughout the process. As we gather more long-term data and refine our techniques, I expect clear aligner therapy to play an increasingly important role in early orthodontic intervention.
References:
1. Moravedje Torbaty, Parisa, et al. “Vertical and transverse treatment effects of Invisalign First system compared to Hyrax maxillary expanders with fixed appliances in mixed dentition patients.” The Angle Orthodontist (2024).
2. Buonocore, Gerarda. “Clear aligner therapy in children: case reports of phase I treatment.” Journal of Clinical Orthodontics: JCO 57.2 (2023): 87-100.
3. Wang, Junbo, et al. “Dimensional changes in the palate associated with Invisalign First System: a pilot study.” The Angle Orthodontist 93.5 (2023): 524-530.
4. Lynch, Nicholas M., et al. “Clear aligner therapy in the mixed dentition: Indications and practitioner perspectives.” American Journal of Orthodontics and Dentofacial Orthopedics 164.2 (2023): 172-182.
