A conversion abutment that cements onto one-piece dental implants that convert the one-piece implant use to a retrievable screw retained implant use in retaining complete dentures, hybrids, partial dentures, or fixed screw retained crowns or bridges, allowing the flexibility to retain and remove these restorative prostheses. These conversion abutments can be fabricated as angled conversion abutments to be used with single or multiple implants placed at various angulations. The conversion abutment system consists of three parts: a cementable conversion abutment (straight or angled), a coping (short or extended), and an occlusal screw. The bottom part (or apical portion) of the implant conversion abutment will cement over the one-piece implant in use, while the top (or coronal portion) will allow a screw to fit through a coping into the implant conversion abutment, screwing the prostheses into place.