. (A) Two-piece implant and abutment (top) and a onepiece implant (bottom) (Zimmer). (B) One-piece implant (Nobel Biocare). (C) One-piece implant replacing tooth #24. (D) The final restoration of the implant replacing tooth #24. (A, Courtesy Zimmer Dental Inc., Carlsbad, CA. B, Courtesy Nobel Biocare USA, Yorba Linda, CA.)