Background and Clinical Significance: Peri-implantitis is an inflammatory condition associated, among other factors, with biofilm accumulation, affecting peri-implant soft and hard tissues and potentially leading to implant loss. Its treatment remains challenging because no single decontamination or regenerative protocol has demonstrated clear superiority. This case report describes a comprehensive surgical and regenerative approach aimed at preserving an affected implant and restoring peri-implant tissue stability; Case Presentation: A systemically healthy 30-year-old patient presented with peri-implant bone loss around an implant in position 25, restored with a lithium disilicate crown and functioning for three years. Treatment included flap elevation, mechanical debridement and air-polishing of the implant surface, followed by thorough irrigation with sterile saline to remove residual abrasive particles and debris, photodynamic antimicrobial therapy, and laser therapy. Bone regeneration was performed using a bone substitute combined with injectable platelet-rich fibrin to produce sticky bone, which was covered with an advanced platelet-rich fibrin membrane. A provisional crown was placed without occlusal contact. After four months, a definitive crown with a modified emergence profile was delivered to improve hygienic access and reduce biofilm retention. Clinical and radiographic follow-up over five years demonstrated stable peri-implant tissues and maintained bone levels; Conclusions: The combined use of surgical decontamination, PRF-assisted regeneration, sticky bone, and prosthetic modification resulted in stable clinical and radiographic outcomes over five years. Identification and elimination of contributing factors were essential for long-term treatment success.