The present dental prosthesis has a palatal implant configured to be implanted subperiosteally and attached to the palatal process by a plurality of fixation screws. The implant has a spine retaining implant magnetic components therealong and having holes for the fixation screws. The prosthesis also has a maxilla denture having a palatal base plate and an alveolar ridge engaging periphery having false teeth installed thereon. The denture is configured to be placed in a mouth to engage a maxilla wherein the alveolar ridge engaging periphery engages an alveolar ridge of the maxilla. The denture comprises a plurality of denture magnetic components configured to align with the implant magnetic components so that the denture is magnetically retained in the mouth by magnetic attraction force between the implant magnetic components and the denture magnetic components.

An implant screw auxiliary device is disclosed, including: a magnet, a bottom portion of the magnet being provided with an output block protruding downwardly, and the magnet being rotatably arranged in a through hole of an implant abutment; a transmission block connected to a top portion of an implant screw; a magnetic field generator for generating a compound magnetic field in a horizontal direction, the compound magnetic field rotating around a vertical axis at a constant speed; a power supply for providing electric energy for the magnetic field generator; and a current detector for measuring a current waveform of the magnetic field generator.