In two separate but related studies, different forms of hydroxyapatite were implanted into the extraction sockets of human teeth to delay alveolar resorption and to form the background for a comparison of the treatment modalities. The significant differences in the treatment modalities and the postoperative sequelae seem to merit this report. The implantation of the particles appears to be clinically, a more expedient procedure than the implantation of cones. The time required to select an appropriate-sized cone, modify the cone as needed to achieve a snug fit into the extraction socket, and seat the cone deeply enough in the extraction socket to assure at least 2 mm of bone above the top of the cone implant was significantly greater than the time required to fit and pack particles into an extraction socket. None of the postimplantation problems encountered with cones was encountered in using the particle implants. The postimplantation problems encountered with cones included submucosal prominence, erosion through the mucosa (dehiscence), migration, loss of the implant, or surgical maintenance or resubmergence. Data from these two studies suggest that the implantation of particles into the extraction sockets of human teeth to delay alveolar ridge resorption is a more prudent, forgiving, considerate, problem-free, and predictable procedure than the implantation of cones.