20-25 Year Follow-Up After Surgical Treatment of Peri-Implantitis Using a Bone Substitute With or Without a Resorbable Membrane: A Longitudinal Study

The aim of this 20-25 year observational follow-up study is to investigate the outcomes of bone regenerative surgery in peri-implantitis. The study compares two approaches: Group 1: surgery with a bone substitute alone (Algipore) and Group 2: surgery with a bone substitute (Algipore) combined with a membrane (Osseoquest). Both groups received systemic antibiotics-Amoxicillin 375 mg three times a day combined with Metronidazole 400 mg twice a day for 10 days, starting the day before surgery.

The objective of this observational study is to gain insights into the long-term effects of bone regenerative surgery in patients with peri-implantitis and to determine if there is a difference.

The patients were enrolled in a strict maintenance program with supportive therapy every third months with a yearly evaluation.

In this study, patients will examined of the surgically treated implant(s) after 20-25 years. The examination will include a clinical assessment, measuring probing pocket depths at each implant to the nearest millimeter using a standardized probing force of 0.25 N (Hawe-Click Probe, Kerr Hawe SA Bioggio, Switzerland). The prevalence of pus, full-mouth bleeding on probing, and bleeding grades will be recorded around the implant(s) at four sites per tooth and implant(s) as follows: 0 = no bleeding, 1 = point of bleeding, 2 = line of bleeding, and 3 = drop of bleeding. The plaque index will be defined as either visible or not visible at the implant site using an erythrosine dye (TopDent Lifco Dental AB, Enköping, Sweden). All clinical assessments will be performed by the same periodontist (AMRJ).

Data from the clinical treatment were registered in patient records. In parallel, clinical data were documented in a study protocol and saved in a safe in accordance with standard operation procedure at the clinic.The protocol with medical records were not opened until the study was completed and only by authorized persons with access to the data in the study such as, principal investigator and statisticians.