Evaluating the accuracy (precision and trueness) of conventional and digital Intraoral Impression Technique.


  • Lana Shwan Jalal Department of Department of Basic Science, College of Dentistry, Hawler Medical University, Erbil, Iraq.
  • Dara Hamarashid Saeed Department of Conservative, College of Dentistry, Hawler Medical University, Erbil, Iraq.




Precision, trueness, accuracy, impression, intraoral scanner


Background and Objectives: This study aims to compare and evaluate the accuracy of the conventional and digital intraoral scanner impression approaches of the maxillary edentulous arch with indirect fixed restorations.

Methods: Three prepared teeth were used in a reference model created for an inlay and a 3-unit bridge. From conventional impressions, models of stone were created. An intraoral scanner was utilized to produce digital impressions of the reference model (digital models), and then the stone models were scanned with a laboratory scanner. The stereolithography file format was used to export the files. To determine the trueness of preparations and the accuracy of a complete arch, by using 3D analysis software, all datasets were superimposed. To compare the two-model group's accuracy and assess the trueness of the two preparation methods, a test of Mann-Whitney U was utilized.

Results: Significant intergroup precision differences between the two groups (digital and stone) were seen for the complete arch, while the (p) value is smaller than 0.001. Nevertheless, in terms of trueness, there was a significant difference between the models and stone, while the (p) value is smaller than 0.001. Mann-Whitney U test revealed significant differences in trueness among the model groups (stone and digital) (p <.001) and types of preparation (p < .001).

Conclusions: Compared to stone models, digital models' root means square values of the accuracy of the full arch and its trueness of preparations were lower.  Nevertheless, compared to digital models, the trueness of the preparations and the complete arch's accuracy of stone models were inferior.


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How to Cite

Jalal LS, Saeed DH. Evaluating the accuracy (precision and trueness) of conventional and digital Intraoral Impression Technique. EDJ [Internet]. 2023 Jun. 30 [cited 2024 Jul. 25];6(1):50-61. Available from: https://edj.hmu.edu.krd/index.php/journal/article/view/210



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