Intraoral scanners are mobile units consisting of a computer, screen software and camera. They represent an important part of CAD/CAM restorations fabrication. A handpiece can be connected to the unit, but today there are wireless versions too. Their development starte din the eighties of the last century. Today's models collect data using imaging technologies such as triangulation, parallel confocal imaging, active wavefront sampling and stereophotogrammetry. After scanning, the software reconstructs and configures the optical impression. The quality of the created virtual model is affected by numerous factors such as scanning speed and path, presence of saliva and blood, proximity of the camera to the tissue, reflective surfaces, uneven movements, surface curvature. In the research, the accuracy of the scanner was examined using the concepts of trueness and precision. Optical impressions of a single tooth show similar accuracy or even greater precision than analog ones. In cases of making three-member or four-member bridges, optical impressions are generally of equal or superior results compared to conventional ones. The arch quadrant scannig proved to be as accurate as a conventional vinyl polysiloxane impression. In rehabilitation with one implant, digital impression is faster and simpler. Impression corrections are simpler, too. In the case of prosthetic treatment with multiple implants, the accuracy of the scanner has not been sufficiently investigated, but certain studies show a low degree of deviation and a lower variability of distance errors compared to conventional impressions. Distance and angulation errors are currently quite large for the fabrication of prosthetic restorations on multiple implants in the case of edentulous jaws. They are not able to register the centric relation, so in the case of lost support zones and edentulous patients the intermaxillary relations must still be determined by conventional methods. Their biggest advantages are simplicity and speed, while their main disadvantage is the price.