Learning curve of digital intraoral scanning – an in vivo study

Abstract

Background: The spread of digital technology in dentistry poses new challenges and goals for dentists. It is important to involve new methods and devices in university education. The aim of the present in vivo study was to determine the learning curve of IOS described by (1) scanning time and (2) image number (count of images made by intraoral scanner during scanning process). Methods: Ten dental students of Semmelweis University took part in the study. Dental students took digital study impressions using 3Shape Trios 3® (Copenhagen, Denmark) IOS device. Each student took 10 digital impressions on volunteers (for standardization the first and the last patients was the same for each student). The inclusion criteria of patients were full dentition (except missing third molar) and no prosthetic- restorative treatment. Digital impression taking was preceded by a lecture consisting of two parts: education and training. For standardization, the scanning device was calibrated before impression taking, followed by the registration of patient data. Digital impressions were taken of the upper and lower arches, and the bite was recorded according to the manufacturer's instructions. Total scanning time and image number of intraoral scanning were recorded. Results: The difference of scanning time between the first and the tenth digital impressions was significant (p=0.007). The average scanning time of first impressions was 23min 9sec, for tenth impressions it was 15min 28sec. The difference between scanning time of the first and the tenth impressions was 7min 41sec. The average image number of the first impressions was 1964.5, for the tenth impressions it was 1468.6. The difference between number of images of the first and the tenth impressions was 495,9. The curve of image number show decreasing tendency first, then has a trough around the sixth measurement, and rises. Conclusion: The learning curve of IOS can be described with scanning time and image number of digital impression. Scanning time decreases as result of practice. Shorter scanning times are accompanied by poorer coverage quality, the operator has to correct by adding extra images represented by the curve of image numbers which turning into increasing tendency after the sixth measurement.

Marginal and internal fit and intaglio surface trueness of interim crowns fabricated from tooth preparation of four finish line locations

“…Previous studies have reported the accuracy of intraoral scanners and 3D printers 17 – 25 . The intraoral scanner (i500; MEDIT) used in the present study for scanning of preparations and intaglio surfaces reported an accuracy of 20–30 µm with respect to a single tooth according to previous study 35 .…”

“…The intraoral scanner has advantages of superior convenience, fast acquisition time of the virtual model, and superior accuracy (based on scanning for single unit) compared with the conventional method 22 – 25 . However, the use of an intraoral scanner for fixed dental prosthesis still requires a solution from a clinical perspective 26 , 27 .…”

Dental students’ preference and perception on intraoral scanning and impression making

“…Intraoral scanners, as with any impression technique, processes a learning curve [ 35 , 36 ]. Some areas in the mouth might not be easy to capture with intraoral scanners such as the distal surfaces of the last tooth in an arch as well as the proximal surfaces near to a bounded saddle.…”

Marginal and internal fit and intaglio surface trueness of interim crowns fabricated from tooth preparation of four finish line locations

“…The intraoral scanner has advantages of superior convenience, fast acquisition time of the virtual model, and superior accuracy (based on scanning for single unit) compared with the conventional method [22][23][24][25]. However, the use of an intraoral scanner for xed dental prosthesis still requires a solution from a clinical perspective [26,27].…”