EVALUATION OF THE AGREEMENT BETWEEN TWO METHODS FOR MEASURING DENTAL ARCH DIMENSIONS ON DIGITAL AND 3D-PRINTED MODELS

Hoang Le Thuy Truong1, , Truong Nhu Ngoc Vo2
1 Hong Bang International University
2 School of Odonto-Stomatology - Hanoi medical University

Main Article Content

Abstract

Objectives: To evaluate the reliability and agreement between the two methods of dental arch dimension measurements. Methods: A descriptive study was conducted on 40 digital models and 40 3D-printed models (printed from March 2025 to January 2026), derived from the same intraoral scan data. Measurements on digital models were performed using Medit Ortho Simulation software and on 3D-printed models using a Mitutoyo digital caliper. The measured parameters included inter-canine width, inter-molar width, anterior arch length, and posterior arch length. Results: No statistically significant differences were observed between the two model types across all dimensions (p > 0.05), except for the lower anterior arch length. Pearson correlation analysis revealed a very strong linear correlation between the two methods (r > 0.977; p < 0.001). The ICC(2,1) > 0.9 (p < 0.001) indicated high agreement and reliability between the two methods. Bland-Altman analysis revealed a very small systematic error (0.02 - 0.19mm), with 95% limits of agreement (LoA) ranging from -0.91 to +1.28mm. Conclusion: Dental arch dimension measurements on digital models using software and on 3D-printed models using a digital caliper demonstrate high reliability and agreement. After 9 months of storage, both model types from the same scan data can be used interchangeably.

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References

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