||Congenital mandibular bone defects or defects due to tumor resection or trauma often result in substantial functional and aesthetic problems. The most common method for reconstructing extensive bony mandibular defects uses a free vascularized fibula flap. But for patients that do not require vascularized bone or soft tissue transfer, the use of custom designed scaffold implants that may hold bone substitutes has the potential to reduce morbidity, cost, and rehabilitation time. Today, implant design and manufacturing are often outsourced, and generally several iterations with the surgeon are required, resulting in a lead time to surgery of many days or weeks. I will describe a semi-automatic method for implant design, based on deformable models and haptics, that should allow the surgeon him/herself to design, adjust, and virtually test the fit of a scaffold implant, before sending it for production. This work will be presented later this year at the CARS conference in Fukuoka, Japan.