Fig. 1. (A) Schematic illustrations of the components of the implant, abutment and abutment screw in external hex implants. (B) Schematic illustrations of the components of the implant, abutment and abutment screw in internal hex implants. (C) Cross-sectional view of abutment-implant assemblies for external hex implants. (D) Cross-sectional view of abutment-implant assemblies for internal hex implants.