5.2 Generating CAD model of an individual wire which 
accurately goes through the brackets slots 
The procedure of slot position determination results in slot 3D 
markers (Fig. 8), which are located in space accordingly slot 
position and orientation. These slot 3D markers then exported 
to required CAD/CAM format for producing individual wire by 
chosen CAM technology. 
  
Figure 8. Slot 3D markers 
The result of export to .dxf format for laser cutting machine is 
shown in Figure 9. 
sé ed 
v 
Figure 9. Slot positions export to .dxf format for automated wire 
production 
6. IMAGE-BASED MONITORING OF TREATMENT 
PROCESS 
For monitoring the process of teeth moving image-based 
technique is proposed. It uses the photograph of patient teeth 
arch at different stages of treatment and 3D model of teeth arch 
for current case. For analysing the results of treatment expert 
could use 3D model of teeth arch in initial or in perfect 
position. 
Exterior orientation of the photograph based on a set of 
reference points is performed thus giving to the expert the 
possibility to analyse real teeth displacement relatively initial or 
desired condition. 
568 
  
  
Figure 10. Image-based monitoring of treatment 
7. CONCLUSION 
The image based technique for orthodontic planning, treatment 
and documenting is proposed. It includes photogrammetric 
system for teeth arches 3D reconstruction, occlusion 
registration, accurate bracket's slot position determination. 
The developed technique provides correct teeth arch set up 
based on occlusal plane determination and accurate teeth 
dimensions measurement. Virtual teeth setup is used for 
individual wire (a set of wires for staged treatment) design and 
automated manufacturing. An orthodontist has a mean for 
monitoring treatment process by comparing 3D model of teeth 
arch (in initial or desired condition) with oriented current 
photograph of patient teeth arch. 
The developed technique was tested in orthodontic practice and 
demonstrated better results than traditional standard bracket 
technology. 
8. REFERENCES 
Knyaz V.A., Zheltov S.Yu., On-line calibration technique for 
mobile robot. EOS Conference on Industrial Imaging and 
Machine Vision, Munich, Germany, June 13-15, 2005, pp. 95- 
97 
Besl, P.J., McKay, N.D., 1992: A method for registration of 3- 
D shapes, IEEE Transactions on Pattern Analysis and Machine 
Intelligence, vol. 14, no.2, pp. 239-256 
Knyaz V., Zheltov S., Gaboutchan A., Bolshakov G. 
Photogrammetric system for automated teeth arches 3D models 
generation and teeth occlusion analysis. Proceedings of “Optical 
3D measurements techniques" 2007, Zurich, Switzerland, pp. 
135-140 
Bh