A supporting device (10) of preformed elements for producing single superstructures of dental prostheses, of the type consisting of a supporting body comprising an interface (8) for supporting a preformed element (2) with respect to the same device. According to the invention, said supporting body has a stem (17, 24) provided with an element (20, 26) housed in correspondence with said stem and which has a surface (22, 27) for supporting the preformed element (2) with respect to the same supporting body, wherein said supporting surface (22, 27) has larger dimensions than those of the above-mentioned interface (8).
With respect to the known embodiments in the field, the device of the invention offers the advantage of also resisting side milling loads of the preformed element, which can therefore also withstand the side loads necessary for producing undercuts and processings below the emergency profile. Thanks to the device of the invention, in fact, the loads generated by side-oriented processings with respect to the preformed element are converted to axial or vertical forces, which even small-dimensioned screws are able to resist.