Introduction: Study models are an essential part of an orthodontic record. Digital models are now available. One option for generating a digital model is cone-beam computed tomography (CBCT) scanning of orthodon- tic impressions and bite registrations. However, the accuracy of digital measurements from models generated by this method has yet to be thoroughly evaluated. Methods: A plastic typodont was modiﬁed with reference points for standardized intra-arch and interarch measurements, and 16 sets of maxillary and mandibular vinyl- polysiloxane and alginate impressions were made. A copper wax-bite registration was madewith the typodont in maximum intercuspal position to accompany each set of impressions. Continue reading Analysis of intra-arch and interarch measurements from digital models with 2 impression materials and a modeling process based on cone-beam computed tomography
Objective: To determine if measurements obtained from digital models from cone beam computed tomography (CBCT) images were comparable to the traditional method of digital study models by impressions.
Materials and Methods: Digital models of 30 subjects were used. InVivoDental (Anatomage, San Jose, Calif) software was used to analyze CBCT scans taken by a Galileos cone beam scanner (Sirona, Charlotte, NC) with a field of view of 15 3 15 3 15 cm3 and a voxel resolution of 0.125 mm. OrthoCAD (Cadent, Fairview, NJ) software was used to analyze impression scans of patients at different stages of orthodontic treatment. Impressions were taken using alginate and were mailed to OrthoCAD for digital conversion. The scans were then electronically returned in digital format for analysis. Continue reading Evaluation of CBCT Digital Models and Traditional Models Using the Little’s Index
Korbmacher H, Kahl-Nieke B, Schöllchen M, Heiland M. Value of two cone-beam computed tomography systems from an orthodontic point of view. J Orofac Orthop 68:278- 289, 2007.
SUMMARY by Dr. DALIA BASYONI :
* CBCT cannot replace OPG, which remains our primary imaging modality.
* In complex cases involving multiple findings in different regions, CBCT is more desirable than conventional radiographs.
* Standard operating procedures (SOP) to use CBCT:
• clefts of the lip, jaw and palate and cases of impacted teeth. Continue reading Value of two cone-beam computed tomography systems from an orthodontic point of view.