Regenerative Outcomes for Peri-implant Bony Defects Using Amnion-chorion Barrier vs. Collagen Membrane

Inclusion Criteria: * Systemically healthy adults (≥18 years) with a diagnosed peri-implantitis lesion requiring surgical intervention of any ethnicity * Comprehension of treatment plan and research project. * Presence of a single implant in function for at least one year. * Radiographic evidence of peri-implant bone loss not exceeding one-third of the implant length. * 2-3 wall defects amenable to guided bone regeneration (GBR). * Screw-retained, posterior, self-cleansing implant prosthesis. * Commitment to maintaining oral hygiene and attending follow-up visits. Exclusion Criteria: * Patients who have had a history of periodontitis, diabetes, smoking habit, or have been prescribed medications that may interfere with bone healing and metabolism * Patients with allergies to any treatment devices * Patients who have a lack of keratinized mucosa (\<2 mm), or positioning for implants or restorative designs that compromise oral hygiene * Peri-implant bone defects not attributable to peri-implantitis (e.g. surgical iatrogenic, trauma) * Anterior implant restorations (#'s 6-11, #'s 22-27) or cement-retained restorations