['The aim of this study was to describe the revascularization process of autogenous bone block grafts placed with or without an expanded polytetrafluoroethylene (e-PTFE) membrane.', 'Thirty Wistar male rats had their mandibles augmented by either an autogenous bone block graft (group A) or an autogenous bone block graft covered with an e-PTFE membrane (group B). The animals were sacrificed by perfusion at baseline, 3, 7, 14, and 21 days after surgery.', 'After 3 days, the presence of vascular sprouts derived from the recipient bed was observed in group A; more discrete sprouts were also observed in group B. After 7 days, revascularization continued, with vessels derived from both the recipient bed and the surrounding connective tissue in group A but only from the recipient bed in group B. At 14 days, group A showed penetration of vessels at the periphery of the graft; the vessels reached varying distances inside it. In group B, revascularization of the graft occurred mainly near its perforation, its borders, and at the recipient bed-graft interface. After 21 days, graft vascular penetration could be observed throughout the extent of the graft in group A but only approximately halfway through the graft in group B.'] Does revascularization of autogenous block graft with or without an e-PTFE membrane?