Date of Award


First Advisor

James Chen

First Committee Member

Heeyeon Suh

Second Committee Member

Sandra Khong Tai

Third Committee Member

Heesoo Oh


Objectives: This study aimed to examine the treatment outcome of correcting class II malocclusion with maxillary molar distalization using clear aligners in both growing and nongrowing patients. Material and Methods: Total of 42 patients (31 growing and 11 non-growing) who underwent non-extraction clear aligner therapy with maxillary molar distalization were selected and compared to 20 subjects who did not undergo orthodontic treatment were selected from American Association of Orthodontists Foundation (AAOF) legacy collection. Thirteen cephalometric measurements and molar relationships on the digital casts at pre-treatment (T1), end -of-active-treatment (T2) for the treatment group (growing and non-growing) and control group were obtained. Results: There were no statistical significance in the skeletal changes (SNA, SNB, and ANB) between the growing treatment group and the control group. Wits decreased significantly (p<0.05) and the upper incisor retroclined significantly (p>0.05) for the growing treatment group. The average molar correction for the whole treatment group were - 1.76mm and -1.43mm for the right and the left side respectively (negative sign indicates correcting to class I) The average molar corrections for the growing treatment group were - 1.92mm and -1.47mm for right and left side respectively. For the control group, the right side became more class II (+0.58mm) and left side maintained (-0.08mm). Conclusions: Maxillary molar distalization using clear aligner therapy successfully corrected class II malocclusion in both growing and non-growing patients predominantly due to dentoalveolar changes. For the growing patients, the treatment corrected class II malocclusion which would not have corrected on its own without treatment intervention.