All ETDs from UAB

Advisory Committee Chair

Chung H Kau

Advisory Committee Members

Rama K Chavali

Amjad Javed

Christos Vlachos

Document Type


Date of Award


Degree Name by School

Master of Science in Dentistry (MScD) School of Dentistry


The aim of this study is to review the state of art concerning 3D optical acquisition techniques and devices currently used in Orthodontics, and determine whether a commercial intra-oral scanner is as accurate as traditional impressions for orthodontic purposes. Materials and Methods: Records of 30 subjects were prospectively acquired and digital models were obtained using an intra-oral scanner, LythosTM by Ormco, and an extra-oral scanner, GOM ATOS Triple Scan II by GOM. Seven parameters indicating linear measurements from predetermined landmarks were measured and analyzed. Paired t tests, plots and bars and Bland and Altman Analysis were used to compare and evaluate measurements made from the study models. In addition, color histograms were used to qualitatively evaluate the volume of the models. Results: The mean difference between the maxillary Lythos models and the maxillary GOM ATOS models ranged from -0.03 to 0.27 mm. The mean difference between mandibular Lythos models and mandibular GOM ATOS models ranged from -0.03 to 0.08 mm. Paired t tests (P < 0.001) were applied to all data obtained from Lythos and GOM ATOS models. Plot and bars, Bland and Altman analysis and color histograms were also applied to the data. The results were not statistically significant for both groups. Conclusions: The results showed that the linear measurements obtained from Lythos models indicated a good level of accuracy when compared with GOM ATOS models. The accuracy was considered adequate for initial diagnosis and treatment planning in orthodontics.

Included in

Dentistry Commons



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