Comparison of the accuracy of implant impression by conventional open-tray and digital techniques


  • Joanna Majid Hayder Department of Prosthodontic Dentistry, College of Dentistry, Tishik International University, Erbil, Iraq.
  • Fahd Sudad Ikram Department of Prosthodontic Dentistry, College of Dentistry, Hawler Medical University, Erbil, Iraq.



Digital implant impression, Open-tray impression technique, Intra-oral scanner, Abutment level impression


Background and objective: Precision of the impression taken from implants significantly determines the accurate fit of implant-supported prostheses. An imprecise impression may produce prosthesis misfit. This study aimed to evaluate the accuracy of the digital implant impression technique as compared to the conventional technique.
Method: A definitive maxillary edentulous model with four implants, two of them 10° anterior-posteriorly angulated, and the other two were parallel implants served as the standard reference for making all the impressions and later for accuracy evaluation. Two groups of ten samples were evaluated, first: open-tray implant impression technique, second; digital implant impression technique. All the models have been saved as standard tessellation language files and converted from 3- Dimensional to 2-Dimensional to calculate the distances between the center of the implants, and the implant angulations measurements by both design programs sketch up, and Auto CAD. Corresponding means for each technique and the definitive reference model were compared by using the t-test test.
Results: There was a statistically significant difference between the digital impression technique models and the reference model concerning the distances between the center of the four implants (A, B, C, and D) with p-value of 0.027 and 0.000, respectively. Regarding the angular distortion, there was also a statistically significant difference between the digital and conventional implant impression models with the reference model.
Conclusion: It has been concluded that the digital implant impression models in a single angulated implant was more accurate than the traditional open tray models, whereby for a long span, a conventional open tray impression technique is preferable.
Keywords: Digital implant impression, Open-tray impression technique, Intra-oral scanner, Abutment level impression.


Att W, Bernhart J, Strub JR. Fixed Rehabilitation of the Edentulous Maxilla: Possibilities and Clinical Outcome. J Oral Maxillofac Surg. 2009;67(11):60–73.

Branemark P-I. Osseointegration and its experimental background. J Prosthet Dent. 1983;50(3):399–410.

Papaspyridakos P, Chen C-J, Singh M, Weber H-P, Gallucci GO. Success Criteria in Implant Dentistry: A Systematic Review. J Dent Res. 2012;91(3):242–8.

Karl M, Winter W, Taylor TD, Heckmann SM. In vitro study on passive fit in implant-supported 5-unit fixed partial dentures. J Oral Maxillofac Implants. 2004;19(1):30–7.

Al-Turki LEE, Chai J, Lautenschlager EP, Hutten MC. Changes in prosthetic screw stability because of misfit of implant-supported prostheses. Int J Implant Dent. 2002;15(1)2002.

Ender A, Mehl A. Accuracy of complete-arch dental impressions: a new method of measuring trueness and precision. J Prosthet Dent.2013;109(2):121–8.

Wo ̈stmann B, Rehmann P, Balkenhol M. Influence of impression technique and material on the accuracy of multiple implant impressions. Int J Prosthodont. 2008;21(4):299–301.

Papaspyridakos P, Chen CJ, Gallucci GO, Doukoudakis A, Weber HP, Chronopoulos V. Accuracy of implant impressions for partially and completely edentulous patients: a systematic review. Int J Oral Maxillofac Implants. 2014;29(4):836–45.

Chia VA, Esguerra RJ, Teoh KH, Teo JW, Wong KM, Tan TB. In vitro three-dimensional accuracy of digital implant impressions: the effect of implant angulation. Int J Oral Maxillofac Implants. 2017;32(2):313–32.

Alikhasi M, Siadat H, Nasirpour A, Hasanzade M. Three-Dimensional Accuracy of Digital Impression versus Conventional Method: Effect of Implant Angulation and Connection Type. Int J Dent. 2018;4(20):1–9.

Lee H, So JS, Hochstedler J, Ercoli C. The accuracy of implant impressions: a systematic review. J Prosthet Dent. 2008;100(4):285–91.

Amin S, Weber HP, Finkelman M, El Rafie K, Kudara Y, Papaspyridakos P. Digital vs. conventional full-arch implant impressions: a comparative study. Clin Oral Implants Res. 2016;28(11)1360–7.

Andriessen FS, Rijkens DR, van der Meer WJ, Wismeijer DW. Applicability and accuracy of an intraoral scanner for scanning multiple implants in edentulous mandibles: a pilot study. J Prosthet Dent. 2014;111(3):186–94.

Basaki K, Alkumru H, De Souza G, Finer Y. Accuracy of digital vs. conventional implant impression approach: a three-dimensional comparative in vitro analysis. Int J Oral Maxillofac Implants. 2017;32(4):792–9.

Joda T, Bra ̈gger U. Patient-centered outcomes comparing digital and conventional implant impression procedures: a randomized crossover trial. Clin Oral Implants Res 2017;27(12):e185–9.

Papaspyridakos P, Gallucci GO, Chen CJ, Hanssen S, Naert I, Vandenberghe B. Digital versus conventional implant impressions for edentulous patients: accuracy outcomes. Clin Oral Implants Res. 2016;27(4): 465–72.

Conrad HJ, Pesun IJ, DeLong R, Hodges JS. Accuracy of two impression techniques with angulated implants. J Prosthet Dent. 2007;97(6):349–56.

Zimmermann M, Mehl A, Mörmann WH, Reich S. Intraoral scanning systems - a current overview. Int J Comput Dent. 2015;18(2):101–29.

Lim J-H, Park J-M, Kim M, Heo S-J, Myung J-Y. Comparison of digital intraoral scanner reproducibility and image trueness considering repetitive experience. J Prosthet Dent. 2018;119(2):225–32.

Giménez B, Özcan M, Martínez-Rus F, Pradíes G. Accuracy of a digital impression system based on parallel confocal laser technology for implants with consideration of operator experience and implant angulation and depth. Int J Oral Maxillofac Implants. 2014;(29):853–62. jomi.3343

Park G-H, Son K, Lee K-B. Feasibility of using an intraoral scanner for a complete-arch digital scan. J Prosthet Dent. 2019;121(5):803–10.

Aragón MLC, Pontes LF, Bichara LM, Flores-Mir C, Normando D. Validity and reliability of intraoral scanners compared to conventional gypsum models measurements: a systematic review. Eur J Orthod. 2016;38(4):429–34.

Carvalho TF, Lima JFM, de-Matos JDM, Lopes G da RS, Vasconcelos JEL de, Zogheib LV, et al. Evaluation of the Accuracy of Conventional and Digital Methods of obtaining dental impression. Int J Odontostomat. 2018;12(4):368–75.




How to Cite

Hayder JM, Ikram FS. Comparison of the accuracy of implant impression by conventional open-tray and digital techniques . EDJ [Internet]. 2022 Jul. 30 [cited 2023 Jun. 4];5(1):1-8. Available from:



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