Pages 67-81, Language: EnglishCavicchia / BraviThe placement of osseointegrated implants in extraction sockets is a commonly used and reliable procedure. Many operative protocols have been suggested for use with both submerged and nonsubmerged implants, and some prerequisites have been defined for their successful placement. Dealing exclusively with implants placed in intact extraction sockets, this paper reviews these commonly suggested prerequisites, discusses their clinical relevance, and presents case reports in which clinical success was obtained despite the violation of more than 1 of these factors. Techniques to obtain primary implant stability, procedures to regenerate residual bone defects, the need to submerge implants in the healing phase, and treatment strategy in infected sites are reviewed. Because the simultaneous violation of some prerequisite factors allows postextractive implants to be performed with a single surgical approach, a new classification is proposed based on the number of surgical stages required to replace a failing tooth with an implant-supported restoration.