Pathologic Mandibular Fracture Associated with Bilateral Dentigerous Cysts in a Dog

This report describes the management and computed tomographic (CT) follow-up of a pathologic fracture of the mandibular body associated with bilateral dentigerous cysts in a 16-month-old Boxer. Bilateral, rostral, mandibular lesions consistent with dentigerous cysts were identified by intraoral radiography and CT. The left cyst was associated with an open, mildly displaced mandibular fracture. Treatment of the cystic lesions consisted of surgical exposure, extraction of embedded teeth, curettage of the cyst lining, and placement of demineralized bone matrix. Reduction and stabilization of the fracture were achieved by interdental wiring combined with an intraoral splint. Follow-up examination and CT imaging were performed at 8, 18, and 85 weeks postoperatively. Complete fracture healing and resolution of both cystic lesions were confirmed at 18 weeks with no recurrence evident at 85 weeks. No complications were encountered. To the authors' knowledge, this is the first case report of a pathologic mandibular fracture secondary to a dentigerous cyst in a dog, documenting the healing of dentigerous cysts via CT with progressive replacement of demineralized bone matrix by new osseous growth. Surgical treatment of the pathologic mandibular fracture and the bilateral dentigerous cysts resulted in an excellent clinical outcome.