A Multi-Centre Randomised Controlled Trial Comparing dPTFE Membrane to Collagen Membrane in Lateral Bone Augmentation at Single Sites in the Anterior Maxilla: 1-Year Results.

AIM To compare a dense polytetrafluoroethylene (dPTFE) membrane with a collagen membrane in guided bone regeneration for lateral bone augmentation at single sites in the anterior maxilla in terms of alveolar width, height, complications, need for additional therapy and implant outcomes. MATERIALS AND METHODS Patients with a class 4 defect at a single site in the anterior maxilla (15-25) were recruited at five centres. Following flap elevation and conditioning of the recipient site, they were randomly allocated to the dPTFE membrane group or the collagen membrane group. Nine months following bone augmentation, re-entry was performed and implants were placed. Alveolar dimensions were assessed on superimposed cone-beam computed tomography images taken prior to surgery, immediately post operation and at 9 months. Implant outcomes were registered 1 year after bone augmentation. RESULTS Thirty-six patients were randomised (dPTFE membrane group: 8 females, 10 males, mean age 39; collagen membrane group: 14 females, 4 males, mean age 51) and all complied until the 1-year follow-up. At 9 months, the estimated marginal mean alveolar width was not significantly different between the groups (estimated marginal mean difference at 3 mm below the crest: 0.65 mm; 95% CI: -0.82 to 2.12; p = 0.381). Infection occurred in 6/18 patients treated with a dPTFE membrane and in 0/18 patients treated with a collagen membrane (p = 0.019). Infection occurred in every centre and had a negative impact on the alveolar width at 9 months, despite taking anti-infective measures in every patient and additional bone augmentation in two patients. Implants could be installed in a prosthetically driven position, integrated uneventfully and yielded minimal marginal bone loss. CONCLUSION dPTFE membrane and collagen membrane are both effective in lateral bone augmentation. However, dPTFE membrane is more prone to infection than collagen membrane, thereby increasing the need for additional therapy. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT05426616.