Histopathology of ossicular implants.

Ossicular and cortical bone grafts maintain their morphologic structure for long periods of time and show varying amounts of replacement of nonviable bone by new bone through a slow process of creeping substitution. Cartilage grafts develop chondromalacia, lose stiffness, and tend to be resorbed over time. Plastipore prostheses elicit foreign body giant cell responses with microscopic biodegradation of the implants. There is a great need for the study of well-documented human temporal bone cases with in situ ossicular implants.