Outcome assessment of orthodontic clear aligner vs fixed appliance treatment in a teenage population with mild malocclusions.

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The Angle orthodontist


oregon; portland; Adolescent; Humans; Malocclusion; Orthodontic Appliance Design; Orthodontic Appliances, Fixed; Orthodontic Appliances, Removable; Outcome Assessment, Health Care; Retrospective Studies; Treatment Outcome


OBJECTIVE: To assess the efficacy and efficiency of treatment in adolescents presenting with mild malocclusions, comparing outcomes using clear aligners to fixed appliances.

MATERIALS AND METHODS: Patients identified retrospectively and consecutively from one private practice had been treated with either clear aligners (Invisalign, Align Technology, Santa Clara, Calif) or fixed appliances (0.022 Damon, Ormco, Orange, Calif; n = 26/group). Assessments of occlusion were made using the American Board of Orthodontics Discrepancy Index (DI) for initial records and Cast-Radiograph Evaluation (CRE) for final records. Number of appointments, number of emergency visits, and overall treatment time were determined from chart reviews. Data were analyzed using Pearson's correlation, Wilcoxon rank tests, unpaired t-tests, and Chi-square tests, with significance set to P ≤ .05.

RESULTS: Pretreatment, the aligner and fixed groups showed no significant difference in overall severity (DI: 11.9 ± 5.3 vs 11.6 ± 4.8) or in any individual DI category. Posttreatment scores showed finishes for the aligner group had fewer discrepancies from ideal relative to the fixed appliance group (CRE: 30.1 ± 8.3 vs 37.0 ± 9.3; P < .01). Patients treated with aligners had fewer appointments (13.7 ± 4.4 vs 19.3 ± 3.6; P < .0001), fewer emergency visits (0.8 ± 1.0 vs 3.6 ± 2.5; P < .0001), and shorter overall treatment time (16.9 ± 5.7 vs 23.4 ± 4.4 months; P < .0001).

CONCLUSIONS: Outcomes for treatment of mild malocclusions in adolescents showed equivalent effectiveness of clear aligners compared to fixed appliances, with significantly improved results for clear aligner treatment in terms of tooth alignment, occlusal relations, and overjet. Assessment of the number of appointments, number of emergency visits, and overall treatment time showed better outcomes for treatment with clear aligners.

Clinical Institute

Women & Children