Comparative in vitro evaluation of the accuracy of dental open system scanners

Relevance. Contemporary Desktop scanner provides accuracy up to 5-15 micron according to the manufacturers, whereas the accuracy of intraoral scanners is near 25-30 micron. Foreign researches point out significant deviations, in some cases of more then 165 micro, of actual accuracy of different types of intraoral scanners in case dental arches scanning. Utilisation of such devices for prosthesis production can lead to unacceptable for the prosthodontic standards size of the clearance between prosthesis and its prosthetic bed.

Purpose. Comparative assessment of actual accuracy of open system desktop and intraoral scanners for getting dental models.

Materials and methods. The control model was produced using ExoCAD software and FormLab 3D printer. The model was scanned by 4 intraoral scanning devises (Identica i500, MyCrown Scan, PlanScan and Trios Wireless) and 3 stationary devices (Identica Hybrid, Open Technologies Easy and Open Technologies Neway). The matching of the scanned files and 3D analysis of the reference CAD model with test CAD models was performed in Geometric Control X software. Statistical analysis of the acquired data was performed by IBM SPSS 25.

Results. TRIOS3 Wireless showed the best accuracy among intraoral scanners (82.6 mkm) the worst result in accuracy of the acquired data was for PlanScan (224,4 mkm). Open Technologies Easy was the most accurate among desktop scanners (53.9 mkm) and the least accurate is Open Technologies NeWay (72,48 mkm).

Conclusion. Low accuracy of the intraoral scanning of the whole dental arch does not permit to use it for getting working model in case of production of the long span bridges especially in case of implant supported prosthetics.

1. V. V. Kostyukova, A. N. Ryahovskij, M. M. Uhanov. Comparative study of intraoral 3D digital scanners for restorative dentistry. Stomatologiya. 2014;93(1):53-59. (In Russ.). https://www.mediasphera.ru/issues/stomatologiya/2014/1/030039-17352014115.

2. I. Yu. Lebedenko, R. G. Nazaryan, M. T. Ashortiya, M. R. Agametov, I. V. Shchepinova. Studying the accuracy of scanning prints and plaster models of clinical laser scanner. Russian Journal of Dentistry. 2015;19(3):4-5. (In Russ.). http://www.medlit.ru/journalsview/dentistry/view/journal/2015/issue-3/232-izuchenie-tochnosti-skanirovaniya-ottiskov-i-gipsovyh-modeley-lazernym-laboratornym-skanerom/.

3. L. Yu. Orekhova, V. G. Atrushkevich, D. V. Mikhalchenko, I. A. Gorbacheva, N. V. Lapina. Dental health and polymorbidity: analysis of modern approaches to the treatment of dental diseases. Parodontologiya. 2017;22(3):15-17. (In Russ.). https://www.parodont.ru/jour/article/view/121/121.

4. V. N. Trezubov, V. L. Popov, R. A. Rozov. Dental forensic identification of the user of a complete removable denture. Stomatologiya. 2020;99(1):43-48. (In Russ). https://doi.org/10.17116/stomat20209901143.

5. J. S. Almeida e Silva, K. Erdelt, D. Edelhoff, É. Araújo, M. Stimmelmayr, L. C. C.Vieira et al. Marginal and internal fit of four-unit zirconia fixed dental prostheses based on digital and conventional impression techniques. Clin Oral Investig. 2014;18:23. https://doi.org/10.1007/s00784-013-0987-2.

6. A. Ender, A. Mehl. In-vitro evaluation of the accuracy of conventional and digital methods of obtaining full-arch dental impressions. Quintessence Int. 2015;46:17. https://doi.org/10.3290/j.qi.a32244.

7. S. B. M. Patzelt, A. Emmanouilidi, S. Stampf, J. R. Strub, W. Att. Accuracy of full-arch scans using intraoral scanners. Clin Oral Investig. 2014;18:94. https://doi.org/10.1007/s00784-013-1132-y.

8. P. Seelbach, C. Brueckel, B. Wöstmann Accuracy of digital and conventional impression techniques and workflow. Clin Oral Investig. 2013;17:64. https://doi.org/10.1007/s00784-012-0864-4.

9. P. Svanborg, H. Skjerven, P. Carlsson, A. Eliasson, S. Karlsson, A. Ortorp. Marginal and internal fit of cobalt-chromium fixed dental prostheses generated from digital and conventional impressions. Int J Dent. 2014;20:53. https://doi.org/10.1155/2014/534382.

10. J. Abduo, M. Elseyoufi. Accuracy of Intraoral Scanners: A Systematic Review of Influencing Factors. Eur J Prosthodont Restor Dent. 2018;26(3):101-121. https://doi.org/10.1922/EJPRD_01752Abduo21.

11. A. Ender, M. Zimmermann, A. Mehl. Accuracy of completeand partialarch impressions of actual intraoral scanning systems in vitro. Int J Comput Dent. 2019;22(1):11-19. https://www.ncbi.nlm.nih.gov/pubmed/30848250.

12. Y. Haddadi, G. Bahrami, F. Isidor. Effect of Software Version on the Accuracy of an Intraoral Scanning Device. Int J Prosthodont. 2018;31(4):375-376. https://doi.org/10.11607/ijp.5781.

13. M. Imburgia, S. Logozzo, U. Hauschild, G. Veronesi, C. Mangano, F. G. Mangano. Accuracy of four intraoral scanners in oral implantology: a comparative in vitro study. BMC Oral Health. 2017;17:92. https://bmcoralhealth.biomedcentral.com/articles/10.1186/s12903-017-0383-4.

14. J. Malik, J. Rodriguez, M. Weisbloom, H. Petridis. Comparison of Accuracy Between a Conventional and Two Digital Intraoral Impression Techniques. Prosthdotontics. 2018;31(2):107-113. https://doi.org/10.11607/ijp.5643.

15. P. Müller, A. Ender, T. Joda, J. Katsoulis. Impact of digital intraoral scan strategies on the impression accuracy using the TRIOS Pod scanner. Quintessence Int. 2016;47(4):343-9. https://doi.org/10.3290/j.qi.a35524.