The immediate placement of a dental implant into a fresh extraction socket has been limited in many instances by the quantity of bone that remains after the extraction. This article presents two clinical cases that demonstrate successfull regeneration of alveolarridges in which there was extensive loss of buccal plate of bone. This lack of alveolar process impeded the immediate placement of dental implants into fresh extraction sockets. The surgical technique performed in these cases was based on the principles of guided bone regeneration using a demineralized freeze-dried bone membrane. The bone membrane acted as an efficient barrier that excluded the non-osteogenic tissues. Bone formation took place for the placement of endosseous dental implants 8 months after the procedures were initiated. These human clinical cases confirm positive results of previous animal findings. (Implant Dent 1999;8:167-172)