Table of Contents
ISRN Dentistry
Volume 2012, Article ID 657973, 7 pages
Research Article

Orthodontic Tooth Movement with Clear Aligners

1Private Practice 310 Susan Drive, Suite 1, Normal, IL 61761, USA
2Department of Biostatistics, University of Florida, Box 117450, FL 32611, USA
3Department of Orthodontics, School of Advanced Dental Sciences, College of Dentistry, University of Florida, Gainesville, FL 32610, USA
4Department of Oral and Maxillofacial Diagnostic Sciences, College of Dentistry, University of Florida, Gainesville, FL 32610, USA

Received 13 April 2012; Accepted 1 July 2012

Academic Editors: D. J. Manton and G. Perinetti

Copyright © 2012 Carl T. Drake et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Clear aligners provide a convenient model to measure orthodontic tooth movement (OTM). We examined the role of in vivo aligner material fatigue and subject-specific factors in tooth movement. Fifteen subjects seeking orthodontic treatment at the University of Florida were enrolled. Results were compared with data previously collected from 37 subjects enrolled in a similar protocol. Subjects were followed prospectively for eight weeks. An upper central incisor was programmed to move 0.5 mm. every two weeks using clear aligners. A duplicate aligner was provided for the second week of each cycle. Weekly polyvinyl siloxane (PVS) impressions were taken, and digital models were fabricated to measure OTM. Initial and final cone beam computed tomography (CBCT) images were obtained to characterize OTM. Results were compared to data from a similar protocol, where subjects received a new aligner biweekly. No significant difference was found in the amount of OTM between the two groups, with mean total OTM of 1.11 mm. (standard deviation (SD) 0.30) and 1.07 mm. (SD 0.33) for the weekly aligner and biweekly control groups, respectively ( 𝑃 = 0 . 7 2 ). Over eight weeks, in two-week intervals, material fatigue does not play a significant role in the rate or amount of tooth movement.