Dental implant systems for releasable attachment of dental prostheses are shown and described. Each of the dental implant systems includes an implant body, a prosthesis body, and an abutment body with a locking device. The locking device includes a magnetically attractable member having a first end coupled to a spring and a second end. The magnetically attractable member is moveable between a locked position and an unlocked position. The dental implant system further includes a void configured to receive the second end, the magnetically attractable member being at least partially disposed within the void in the locked position, the magnetically attractable member being free of the void in the unlocked position.