This retrospective study compared the effects of different extraction sockets when using flapless ridge preservation during dental implant therapy. The extraction sockets were divided into four groups: Class I, intact soft tissue wall and bone walls, Class II, intact soft tissue wall with the destruction of at least one bone wall, Class III, the recession of all soft tissue walls by &le, 5 mm, and Class IV, the recession of at least one soft tissue wall by >, 5 mm. We compared clinical parameters of dental implant therapy using flapless ridge preservation among these groups. Seventy patients with 92 dental implants, including 53 maxillary and 39 mandibular implants, involving flapless ridge preservation were enrolled. The implant survival rate was not affected by socket morphology. Total treatment time from extraction to final prosthesis placement was significantly longer in Class II and III than in Class I, among the maxillary sockets. However, there was no significant difference in the total treatment time among the different groups in the mandible. Therefore, implant survival rates did not differ according to socket morphology, however, total treatment time was significantly affected by socket morphology in the maxilla and was longer in socket classes associated with periodontitis.