Comparison of clinical bracket point registration with 3D laser scanner and coordinate measuring machine.
OBJECTIVE
The aim of the present study was to assess the diagnostic value of a laser scanner developed to determine the coordinates of clinical bracket points and to compare with the results of a coordinate measuring machine (CMM).


METHODS
This diagnostic experimental study was conducted on maxillary and mandibular orthodontic study casts of 18 adults with normal Class I occlusion. First, the coordinates of the bracket points were measured on all casts by a CMM. Then, the three-dimensional coordinates (X, Y, Z) of the bracket points were measured on the same casts by a 3D laser scanner designed at Shahid Beheshti University, Tehran, Iran. The validity and reliability of each system were assessed by means of intraclass correlation coefficient (ICC) and Dahlberg's formula.


RESULTS
The difference between the mean dimension and the actual value for the CMM was 0.0066 mm. (95% CI: 69.98340, 69.99140). The mean difference for the laser scanner was 0.107 ± 0.133 mm (95% CI: -0.002, 0.24). In each method, differences were not significant. The ICC comparing the two methods was 0.998 for the X coordinate, and 0.996 for the Y coordinate; the mean difference for coordinates recorded in the entire arch and for each tooth was 0.616 mm.


CONCLUSIONS
The accuracy of clinical bracket point coordinates measured by the laser scanner was equal to that of CMM. The mean difference in measurements was within the range of operator errors.
Dentofacial Deformities Research Center, Shahid Beheshti University of Medical Sciences, Iran.
Mahtab
M
Nouri
Research Center, Shahid Beheshti University of Medical Sciences, Iran.
Arash
A
Farzan
Faculty of Paramedicine, University of Medical Sciences, Iran.
Ali Reza Akbarzadeh
AR
Baghban
Laser and Plasma Research Institute, Shahid Beheshti University, Iran.
Reza
R
Massudi
D000328:Adult; D059925:Anatomic Landmarks / Q000033:anatomy & histology; D001641:Bicuspid / Q000033:anatomy & histology; D003481:Cuspid / Q000033:anatomy & histology; D003724:Dental Arch / Q000033:anatomy & histology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods / Q000706:statistics & numerical data; D021621:Imaging, Three-Dimensional / Q000379:methods* / Q000706:statistics & numerical data; D007180:Incisor / Q000033:anatomy & histology; D007834:Lasers; D003765:Models, Dental / Q000706:statistics & numerical data; D008963:Molar / Q000033:anatomy & histology; D061848:Optical Imaging / Q000379:methods* / Q000706:statistics & numerical data; D016910:Orthodontic Brackets / Q000706:statistics & numerical data; D015203:Reproducibility of Results; D019228:Tooth Crown / Q000033:anatomy & histology