Document Type : Original Article


1 Private Practice, Gujarat, India

2 Professor of Department of Orthodontics and Dentofacial Orthopedics , Ahmedabad Dental College and Hospital, Gujarat, India


Aim: The purpose of this in-vivo study is to determine and compare the accuracy of dental measurements calculated on physical and digital models with the measurements taken directly from the patients’ mouth.
Methods: This study was performed on 40 subjects. Forty maxillary impressions were produced using a condensation silicone putty material and constructed into a physical model. A digital vernier caliper was utilized to take direct measurements from the patients’ mouth as well as from the physical models. CS 3600® was employed for direct intra-oral scanning for the subjects’ dentition and generating the digital model. Three-dimensional reverse engineering software was used to make measurements on the digital model. One-way ANOVA test was used to determine the accuracy between the control group, physical models, and virtual group. Tukey’s post-hoc analysis was done to compare between the individual group.
Results: There were no statistically significant differences between the physical (p-value=0.254) and virtual models (p-value = 0.168) as compared to those measurements taken directly from the mouth.
Conclusion: The results of the current study demonstrate that intraoral scans are clinically sound to be used in diagnosis and treatment planning in dentistry and provide a professional and well-grounded substitute to the use of conventional plaster models.


Main Subjects

  1. Akyalcin S, Cozad BE, English JD, Colville CD, Laman S. Diagnostic accuracy of impression-free digital models. Am J Orthod Dentofacial Orthop. 2013; 144(6):916-22. doi: 10.1016/j.ajodo.2013.04.024. PMID: 24286915.
  2. Dalstra M, Melsen B. From alginate impressions to digital virtual models: accuracy and reproducibility. J Orthod. 2009;36(1):36-41. doi: 10.1179/146531 20722905. PMID: 19286874.
  3. Christensen GJ. Impressions are changing: deciding on conventional, digital or digital plus in-office milling. J Am Dent Assoc. 2009 ;140(10):1301-4. doi: 10.14219/jada.archive.2009.0054. PMID: 19797561.
  4. Keating AP, Knox J, Bibb R, Zhurov AI. A comparison of plaster, digital and reconstructed study model accuracy. J Orthod. 2008;35(3):191-201. doi: 10.1179/146531207225022626. PMID: 18809782.
  5. Stein JM. Stand-alone scanning systems simplify intraoral digital impressioning. Compendium of Continuing Education in Dentistry. 2011;32(4):56-9. PMID: 22195353.
  6. Naidu D, Freer TJ. Validity, reliability, and reproducibility of the iOC intraoral scanner: a comparison of tooth widths and Bolton ratios. Am J Orthod Dentofacial Orthop. 2013;144(2):304-10. doi: 10.1016/j.ajodo.2013.04.011. PMID: 23910212.
  7. Farah J, Brown L. Integrating the 3M ESPE chairside oral scanner COS into daily clinical practice. Dent Advisor. 2009; 12:1-4.
  8. Kurbad A. Impression-free Production Techniques. Int J Comput Dent. 2011; 14(1):59-66. PMID: 21657126.
  9. Kravitz ND, Groth CH, Jones PE, Graham JW, Redmond WR. Intraoral digital scanners. J Clin Orthod. 2014;48(6):337-47. PMID: 25083754.
  10. Kusnoto B, Evans CA. Reliability of a 3D surface laser scanner for orthodontic applications. Am J Orthod Dentofacial Orthop. 2002 ;122(4):342-8. doi: 10.1067/mod.2002.128219. PMID: 12411877.
  11. Santoro M, Galkin S, Teredesai M, Nicolay OF, Cangialosi TJ. Comparison of measurements made on digital and plaster models. Am J Orthod Dentofacial Orthop 2003;124(1):101–105. doi: 10.1016/s0889- 5406(03)00152-5. PMID: 12867904.
  12. Zilberman O, Huggare J, Parikakis KA. Evaluation of the validity of tooth size and arch width measurements using conventional and threedimensional virtual orthodontic models. The Angle Orthodontist. 2003;73(3):301-6. doi: 10.1043/0003- 3219(2003)073<0301:EOTVOT>2.0.CO;2. PMID: 12828439.
  13. Treesh JC, Liacouras PC, Taft RM, Brooks DI, Raiciulescu S, Ellert DO, Grant GT, Ye L. Complete-arch accuracy of intraoral scanners. J Prosthet Dent. 2018; 120(3):382-8. doi: 10.1016/j.prosdent.2018.01.005. PMID: 29724554.
  14. Park SH, Byun SH, Oh SH, Lee HL, Kim JW, Yang BE, Park IY. Evaluation of the Reliability, Reproducibility and Validity of Digital Orthodontic Measurements Based on Various Digital Models among Young Patients. J Clin Med. 2020;9(9):2728. doi: 10.3390/jcm9092728.