Two patients with reconstruction of a massive mandibular defect with vascularized full-thickness calvarial bone flaps are reported. In Patient 1, the mandibular body developed osteomyelitis and once was replaced with a metallic prosthesis. The prosthesis later perforated the skin and was removed. Full-thickness calvarial bone flaps were elevated bilaterally to reconstruct the mandibular body. In Patient 2, the mandible was totally destroyed by invasion of squamous cell carcinoma. The lower one-half of the face was resected and replaced with a large island scalp flap with full-thickness calvarial bone.