Accuracy of Intraoral Scanners Compare with Conventional Impression Techniques in Vivo Study: A Systematic Review and Meta-analysis


  • Sumana Posritong DDS., MSD, Ph.D, Thai Board of General Dentistry Institute of Dentistry, Department of Medical Services
  • Kannika Chukiatmun DDS., M.D., MsIT, Cert. in OMS Institute of Dentistry, Department of Medical Services


Accuracy, Intraoral scanners, Intraoral digital scanners, Conventional impression techniques, Systematic review, Meta-analysis


Background: The accuracy of dental model is important in dentistry. Acquiring data from an intraoral scanner has different context from that of an extraoral scanner. Thus, researchers try to compare the accuracy of using an intraoral scanner with the conventional impression techniques which includes scanning short distance and scanning full arch, or long distance. This method can evaluate the accuracy in many aspects.Objective: To quantitatively compare the accuracy of intra oral scanning by the scanner with the accuracy of convention impression techniques as well as to re-evaluate its clinical acceptance value as a guide for all dental clinical works.Methods: Related articles were systematically search via PubMed, open Access, Google scholar and manual searches. Articles published in English from 2010 to 2021 were selected. Eighteen articles were then accepted, and their datasets were meta-analyzed by evaluating and comparing the accuracy of using an intraoral scanner with conventional impression technique. Furthermore, subgroup analysis was divided into short distance and long distance, or large object, scanning.Result: The accuracy of short distance scanning was better than conventional impression technique, but not statistically significant (SMD = -0.255; 95% CI = -0.553, 0.042; p = 0.093) due to moderate heterogeneity of data (I2 = 56.4%). The accuracy of scanning for long distance, also known as large object, was worse than conventional method with statistical significance (SMD = 1.808; 95% CI = 0.304, 3.311; p = 0.018) and very high heterogeneity of data (I2 = 96.8%).Conclusion: Intraoral scanners are reliable enough to use in clinical context for short distance scanning. However, the reliability of scanning for long distance or large objects is still at risk of inaccuracy. The reason for heterogeneity remains obscure as the availability of the evidence is limited and further high-quality research is required.


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How to Cite

Posritong S, Chukiatmun K. Accuracy of Intraoral Scanners Compare with Conventional Impression Techniques in Vivo Study: A Systematic Review and Meta-analysis. j dept med ser [Internet]. 2021 Sep. 3 [cited 2023 Jan. 31];46(2):121-3. Available from:



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