Metrological assessment of the trueness of prosthetic metal frameworks manufactured through digital techniques.

The aim of the study was to investigate by two software applications the accuracy and precision of Co-Cr copings made through 4 different technologies, in order to obtain the validation of the dental dedicated measurement software and to evaluate the accuracy and trueness of the obtained alloy copings.

In this study, we analyzed 24 crowns made of Cobalt-Chrome using 4 different techniques to obtain the finished piece. The prosthetic pieces had the same design and were divided into 4 study batches (6 per batch) depending on the method of obtaining as follows: R- resin, W- wax, M- milling, S- sintering. For batches R and W the final piece was obtained through the classic melting and casting process. The restorations had the same master model and the images were captured using a Medit i600 cabinet scanner. Each STL file of each crown was superimposed on the reference STL file (design), using the alignment functions of both the Medit Crown Fit program and the Meshmixer alignment functions in order to quantify the accuracy by analyzing the deviation from the design. The results suggest that both software are capable of producing similar results in terms of deviation from design. The differences are below 0.01 mm, so they can be considered insignificant from a practical point of view.