GBR-based restoration of a peri-implant defect with an equine flexible cortical bone membrane and heterologous equine bone [GBR perimplantare con lamina corticale flessibile di origine equina e osso eterologo equino]

Objectives: To assess the efficacy of peri-implant defect restoration based on the use of partially decalcified equine cortical bone membrane and heterologous equine bone. Materials and methods: We treated a healthy, 48-year-old non-smoking male with a trespassing palatal-vestibular defect (coronal-apical diameter 10 mm, mesiodistal diameter of 4-5 mm). In a single surgical procedure, apical bone was prepared with an osteotome, and an implant was inserted. After achieving primary stability, the membrane was fixed and stabilized with the implant cover screw. The equine bone graft was then used to fill the vestibular and palatal defects, and the membrane was adjusted. After proper flap release, the wound was closed with 5-0 monofilament polyamide sutures and allowed to heal by first intention. Results: Fourteen weeks after surgery, the implants were uncovered, and the regenerated tissues showed clinical signs of healing. The membrane was still present and appeared to be integrated with the surrounding bone tissue. The membrane was biopsied, and histologic examination confirmed that it was still intact and occlusive, which is consistent with the expected behaviour of a bone graft that can be remodeled only by osteoclasts, a process that takes time. Conclusions: Equine cortical bone membrane, together with the heterologous graft, proved to be an optimal choice for anatomic and functional restoration of this peri-implant defect according to the principles of guided bone regeneration