A Second Chance: Managing Late Implant Failure from Peri-Implantitis with Computer-Guided Bone Regeneration-A Clinical Case Report.

Background and Clinical Significance: The retreatment of failed dental implants remains a challenging clinical scenario, particularly when complicated by peri-implantitis and as sociated bone loss. Successful management requires a comprehensive and predictable approach that addresses both hard and soft tissue deficiencies. Case Presentation: This case report illustrates a fully digital, prosthetically driven workflow for the rehabilitation of a posterior mandibular site following implant failure. A 44-year-old female patient underwent removal of a failing implant and adjacent tooth due to advanced peri-implantitis and periodontitis. After healing, a digital workflow-including intraoral scanning, cone-beam computed tomography (CBCT), and virtual planning-was employed to design and fabricate a customized CAD/CAM titanium mesh for vertical guided bone regeneration. The grafting procedure utilized a composite mixture of autogenous bone and anorganic bovine bone (A-Oss). After nine months of healing, two implants with a hydrophilic surface (SOI) were placed using a fully guided surgical protocol (OneGuide system). Subsequent soft tissue grafting and final prosthetic rehabilitation with monolithic zirconia restorations resulted in stable functional and aesthetic outcomes. Conclusions: This case highlights how the integration of modern digital technologies with advanced regenerative procedures and innovative implant surfaces can enhance the predictability and long-term success of implant retreatment in compromised posterior sites.