Vivosorb® as a barrier membrane in rat mandibular defects. An evaluation with transversal microradiography

Vivosorb® is a new degradable membrane composed of poly(DL-lactide-ɛ-caprolactone) (PDLLCL). The aim of this study was to appraise its performance in guided bone regeneration procedures. In 192 rats a 5.0 mm defect was drilled in the mandibular angle. The defects were covered with a membrane (PDLLCL, collagen, or expanded polytetrafluoroethylene (ePTFE)) or left uncovered (control). Defect closure, mineralization and thickness of the new bone were assessed by means of transversal microradiography at three different time intervals (2, 4 and 12 weeks). The data were analysed using multiple regression analyses. The regression analyses showed significant effect modification between time and collagen and time and ePTFE for mineralization of the newly formed bone. For defect closure and bone thickness all membrane-treated groups showed effect modification between time and membrane; these effects were more significant and larger in the collagen and ePTFE groups. In the non-treated controls no effect modification was observed. The membrane groups showed significantly better results than the control groups. The ePTFE and collagen membranes performed equally well and better than the PDLLCL membrane during this experiment. It was concluded that a PDLLCL membrane is not suitable for clinical application in its current form.