Osseointegrated Implants in Vertical Ridge Augmentation with a Nonresorbable Membrane: A Retrospective Study of 75 Implants with 1 to 6 Years of Follow-up

The aim of this study was to retrospectively evaluate 75 implants inserted in vertically augmented bone at the time of or prior to implant placement after 1 to 6 years of prosthetic loading. The study included 21 patients (29 surgical sites). The vertical procedure was performed combining a titanium-reinforced expanded polytetrafluoroethylene membrane with autograft (7 sites), allograft (5 sites), or auto-xenograft (17 sites). Healing was uneventful in 24 surgical sites. Three sites showed premature exposure, and two sites presented an abscess. Two implants were lost, for a cumulative survival rate of 93.6%. Mean bone remodeling at 1, 2, 3, 4, 5, and 6 years was 0.34, 0.72, 1.04, 0.84, 0.56, and 0.61 mm, respectively. The implant success rate was higher with a simultaneous approach (82.5%) compared with a staged approach (66.8%). Implants surrounded by keratinized mucosa revealed a higher success rate (82.1%) than those without it (58.4%).