Objectives: To assess the accuracy in terms of trueness and precision of two-dimensional image-based scanning stereophotogrammetry method compared to extraoral scanner.
Methods: in this study an anatomically prepared maxillary central incisor was scanned using an extraoral scanner as reference control. For Stereophotogrammetry scanning a setup was customised, its construction is based on digital single reflex camera (DSLR) for capturing photos. For standardization the camera is accompanied with a computer-controlled wireless communication Arduino based device to produce photos that fulfil the requirements of this technique ensuring repeatable and overlapping photography. Produced photos were processed using a dedicated stereophotogrammetry software to create three dimensional models exported as standard tessellar language files (STL). To compare accuracy an extraoral desktop scanner was used as control. Scanning was repeated 5 times for both methods. Accuracy was assessed in terms of trueness, and precision was assessed by overlapping the produced STL files using surface matching software. Results: Stereophotogrammetry scanning displayed mean trueness of (39+1 microns), and mean precision (2.8+1.3 microns). The desktop extraoral scanner displayed mean trueness mean (23+3 microns) and mean precision of (17.5+6 microns). Conclusions: Stereophotogrammetry scanning method showed reliable scanning accuracy of prepared teeth and can be used as an affordable alternative scanning method with comparable results to commercially available laboratory desktop extraoral scanners.