Dental implant assemblies, custom dental implants, and custom dental prosthesis and components each individually designed and manufactured to replace nonfunctional natural teeth of a specific pre-identified patient are provided. An example dental prosthesis/assembly includes a transgingival interlock abutment having a prosthesis interface formed therein to receive an occlusally-facing dental prosthesis component, and an implant interface form to receive a dental implant body. The prosthesis interface has a custom three-dimensional surface shape formed to create a form locking fit with respect to the occlusally-facing dental prosthesis component when connected herewith. The implant interface also has a custom three-dimensional surface shape formed to create a form locking fit with respect to the dental implant component when connected therewith.