From Biological Mechanisms to Clinical Outcomes: A Scoping Review Comparing Immediate and Delayed Dental Implant Placement Protocols

<b>Background/Objectives:</b> Dental implant placement protocols including immediate (IIP) and delayed implant placement (DIP) are likely to affect bone tissue repair and regeneration after the surgery. Despite many benefits of IIP, it has remained unclear whether IIP demonstrates comparable healing processes and outcomes to those observed in DIP. This review aims to summarize and compare biological and clinical outcomes of IIP and DIP, focusing on success and survival rates, periodontal status, esthetics and radiographic outcomes, and biochemical markers. <b>Methods:</b> A literature search of electronic databases was conducted using PubMed/MEDLINE, Embase, and the Scopus databases (January 1983-February 2025). 109 articles published in English, consisting of in vitro, in vivo, and clinical studies met the inclusion criteria. <b>Results:</b> This review shows that both IIP and DIP show similar implant survival rates, but IIP may lead to a higher risk of mid-facial recession in esthetic areas. DIP, on the other hand, can result in better soft tissue and bone healing. Histological and radiographic evidence shows comparable bone to implant contact (BIC) between the two methods, although peri-implant bone loss tends to be higher with IIP. Lastly, although specific molecular markers are well-established in all phases of osseointegration following DIP, there is no available literature comparing differences in biomarkers during healing periods between IIP and DIP. <b>Conclusions:</b> This review highlights the similarities and differences in the outcomes of IIP and DIP, as well as the knowledge gaps that require further investigation, providing valuable insights for predicting treatment outcomes and managing complications associated with dental implant placement.