Distalization with Clear Aligners: Accuracy, Impact of Mini-Screws, and Clinical Outcomes

Background: Distalization is a fundamental orthodontic strategy for correcting Class II and Class III malocclusions, particularly in cases where specific dental or skeletal conditions favor its application. Recent technological advances have enabled complex dental movements to be performed using clear aligners, aided by digital planning platforms such as ClinCheck^®. Methods: This retrospective study aimed to evaluate the accuracy of ClinCheck^® in predicting molar and canine distalization outcomes with the Invisalign^® system and to identify clinical factors influencing treatment predictability. Thirty patients with complete permanent dentition and at least 2 mm of programmed distalization were selected. Planned movements were extracted from the Invisalign^® Doctor Site and compared to achieved outcomes using Geomagic^® Control X™ software. Occlusal improvements were assessed using the Peer Assessment Rating (PAR) index. Results: The results revealed significant discrepancies between the programmed and achieved distalization, with mean deviations greater than 1 mm in both arches. Skeletal anchorage with mini-screws significantly improved distalization outcomes in the maxillary arch; however, no significant effect was observed in the mandibular arch. Additionally, no significant associations were found between distalization outcomes and skeletal pattern (ANB angle) or facial biotype. Conclusions: Clear aligners are effective in achieving substantial occlusal improvements, particularly when combined with personalized digital planning and supplementary strategies such as skeletal anchorage. Mandibular cases demonstrated greater reductions in PAR scores, emphasizing the potential of aligners in complex distalization treatments.