Comparison of model analysis measurements among plaster model, laser scan digital model, and cone beam CT image / 대한치과교정학회지

ABSTRACT

OBJECTIVE: The purpose of this study was to evaluate the possibility of using a digital model and cone beam computed tomograph (CBCT) image for model analysis. METHODS: Model analyses of CBCT images, plaster models, and digital models of 20 orthodontic patients with a permanent dentition with no proximal metal restorations, were compared. RESULTS: The average differences of tooth size measurements were 0.01 to 0.20 mm, and the average difference of arch length discrepancy measurements were 0.41 mm in the maxilla and 0.82 mm in the mandible. The difference in Bolton discrepancy measurements was 0.17 mm for the anterior region and 0.44 mm overall but with no statistically significant difference. When comparing CBCT images with plaster models, the average differences in tooth size measurements were -0.22 to 0.01 mm, and the average differences in arch length discrepancy measurements were 0.43 mm in the maxilla and 0.32 mm in the mandible. Difference in Bolton discrepancy measurements were 0.35 mm in the anterior region and 1.25 mm overall. CBCT images showed significantly smaller overall Bolton discrepancy measurements. CONCLUSIONS: Although there were statistically significant differences in some model analysis measurements, the ranges of measurement errors of the digital model and CBCT images were clinically acceptable. Therefore, a digital model and CBCT image can be used for model analysis.