MDI O-Ball Prosthetic Head OB-13 is an O-ball prosthetic head that measures 13 mm and utilizes the LAOB MDI Collared O-Ball Head Analog. The Collared MDI Implant Standard Thread design features a 2.5 mm polished collar that makes it ideal for patients with gingival tissue thicker than 2 mm with D1 or D2 bone. This implant is placed using the MDI patented placement protocol. Suggested Applications Ideal for patients with gingival tissue thicker than 2 mm with D1 or D2 bone. Designed for use with prosthetic parts and components. Used for implant and prosthetic placement.