This report describes a successful implant prosthetic rehabilitation in an atrophic left posterior mandible in a 62-year-old man using a cancellous equine bone block as grafting material. Four months later, two bone specimens were retrieved for histologic evaluation and two dental implants were placed. Computed tomography and conventional radiography showed a 5-mm mean vertical bone gain. The biopsies showed new bone formation within the cancellous portion of the blocks and no foreign body reaction. Cancellous equine bone grafts may be an effective alternative to autogenous bone and inorganic bovine bone grafting for reconstruction of the posterior mandible using the inlay technique.