Pericranium is frequently used in duraplasty and is considered superior to the many other alternatives because of its easy availability and because it offers a watertight dural closure while minimizing the problems of adhesion, infection, and rejection. Although the osteogenic potential of all periosteal tissues is recognized, a review of the literature did not reveal a reported case of osseous formation following use of pericranium for duraplasty. The authors report the case of a 17-year-old man who presented with a self-inflicted gunshot wound to the head. He was obtunded, but moving all extremities purposefully. Computerized tomography scanning demonstrated bifrontal injury. A bicoronal craniotomy with debridement was performed on an emergency basis, with vascularized pericranium used for a duraplasty. Follow-up cranioplasty demonstrated significant ossification of the pericranium 5 months after the original surgery. Pericranium is an attractive material for duraplasty; however, its osteogenic potential may interfere with future cranioplasty and cosmesis. This may be especially relevant in young persons.