Vertical Ridge Augmentation Using Guided Bone Regeneration (GBR) in Three Clinical Scenarios Prior to Implant Placement: A Retrospective Study of 35 Patients 12 to 72 Months After Loading

Purpose: The aims of the current study were to: (1) evaluate the results of vertical guided bone regeneration (GBR) with particulate autogenous bone grafts, (2) determine clinically and radiographically the success and survival rates of 82 implants placed in such surgical sites after prosthetic loading for 12 to 72 months, and (3) compare defects that were treated simultaneously with sinus augmentation and vertical GBR to other areas of the jaw treated with vertical GBR only. Materials and Methods: Eighty-two implants were inserted in 35 patients with 36 three-dimensional vertical bone defects. The patients were divided into three groups: single missing teeth (group A), multiple missing teeth (group B), and vertical defects in the posterior maxilla only (group C). All group C subjects were treated simultaneously with sinus and vertical augmentations. All patients were treated with vertical ridge augmentation utilizing titanium-reinforced polytetrafluoroethylene (e-PTFE) membranes and particulated autografts. After removal of the e-PTFE membrane, all sites received a collagen membrane. Results: At membrane removal, mean vertical augmentation was 5.5 mm (± 2.29 mm). Mean combined crestal remodeling was 1.01 mm (± 0.57 mm) at 12 months, which remained stable through the 6-year followup period. There were no statistically significant differences between the three groups in mean marginal bone remodeling. One defect had a bone graft complication (2.78%, 95% CI: 0.00%, 8.15%). The overall implant survival rate was 100% with a cumulative success rate of 94.7%. Conclusions: (1) Vertical augmentation with e-PTFE membranes and particulated autografts is a safe and predictable treatment; (2) success and survival rates of implants placed in vertically augmented bone with the GBR technique appear similar to implants placed in native bone under loading conditions; (3) success and failure rates of implants placed into bone regenerated simultanously with sinus and vertical augmentation techniques compare favorably to those requiring only vertical augmentation. Schlagwörter: autogenous bone graft, barrier membranes, guided bone regeneration, sinus augmentation, vertical ridge augmentation