Applications of Surface-Surface Matching Algorithms for Determination of Orthodontic Tooth Movements

• Published in: Computer methods in biomechanics and biomedical engineering Vol. 6; no. 5-6; pp. 353 - 359
• Main Authors: Keilig, L., Piesche, K., Jäger, A., Bourauel, C.
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis GroupAbingdon, UK 01.10.2003
• Subjects: Algorithms; Computer Simulation; Coordinate measurement table; Dental Models; Diagnosis, Computer-Assisted - methods; Humans; Image Interpretation, Computer-Assisted - methods; Laser scanner; Models, Biological; Movement - physiology; Orthodontics; Orthodontics - methods; Reproducibility of Results; Sensitivity and Specificity; Surface-surface matching; Therapy, Computer-Assisted - methods; Tooth - anatomy & histology; Tooth - physiology; Tooth Migration; Tooth movement; Tooth Movement Techniques - methods
• ISSN: 1025-5842; 1476-8259
• DOI: 10.1080/10255840310001634403

Orthodontic tooth movements are described as the differences between initial and final tooth positions. A computer based method for determination of tooth movements for different treatment methods was developed. A total of 20 casts of the upper jaw of patients treated with tooth positioners or fixed appliances were used as a basis for this study. Tooth movement was analysed on casts before (C i ) and after treatment (C f ). The casts were digitized either with a COMT or 3D laser scanning systems. After digitization, the models were superimposed in the palate by using a surface-surface matching algorithm. Tooth surfaces of the orthodontically moved teeth were segmented and determination of tooth movement was accomplished by matching the moved teeth from C i to C f . The resulting transformations delivered three dimensional information on translations and rotations. An accuracy of 0.2 mm in translations and 1 degree in rotations could be demonstrated, showing the different efficiency of treatment schemes.