Support device (10) for one or more elements of a dental prosthesis comprising an intraosseous element (11) with a screw, or not with a screw, provided with a clamping seating (17), a supporting body (12) associated with the intraosseous element (11) and provided with an axial cavity (21), a coupling element (13), disposed partly inside the clamping seating (17) and partly in the axial cavity (21), to determine thereby the reciprocal coupling of the intraosseous element (11) and the supporting body (12), and attachment members (15) to keep the intraosseous element (11), the supporting body (12) and the coupling element (13) in a reciprocally assembled condition. The axial cavity (21) of the supporting body (12) comprises a first conical portion (22), which cooperates with a corresponding second conical portion (25) of the coupling element (13), and a first polygonal portion (23) to cooperate with a corresponding second polygonal portion (26) of the coupling element (13).
