US Patent 6981871 Dental attachment assembly and method

A dental attachment assembly has an abutment member for attachment to a tooth root, implant, adjacent tooth, or bar, and a retention member for hinged engagement in a cap secured in a dental appliance. A skirt projects from one end of the cap for releasable snap engagement over an outer locating surface on the abutment member. The outer locating surface has at least two axially spaced retention surfaces for mating, snap engagement with corresponding spaced snap engagement formations on the inner surface of the cap, to provide a stacked, external retention between the abutment and retention members.