Inter-arch digital model vs. manual cast measurements: Accuracy and reliability

Abstract

Objectives: The purpose of this study was to evaluate the accuracy and reliability of inter-arch measurements using digital dental models and conventional dental casts.

Methods: Thirty sets of dental casts with permanent dentition were examined. Manual measurements were done with a digital caliper directly on the dental casts, and digital measurements were made on 3D models by two independent examiners. Intra-class correlation coefficients (ICC), a paired sample t-test or Wilcoxon signed-rank test, and Bland–Altman plots were used to evaluate intra- and inter-examiner error and to determine the accuracy and reliability of the measurements.

Results: The ICC values were generally good for manual and excellent for digital measurements. The Bland–Altman plots of all the measurements showed good agreement between the manual and digital methods and excellent inter-examiner agreement using the digital method.

Conclusion: Inter-arch occlusal measurements on digital models are accurate and reliable and are superior to manual measurements.

Keywords:

• Orthodontics
• inter-arch measurements
• 3D models
• digital measurement