Survival of the cortical bone columella in ear surgery.

Twenty-six partial and twenty-four ossicular replacement grafts were removed from patients because of hearing problems, cholesteatoma or re-perforation. The ossicles had been inserted in the middle ear between 7 and 121 months. The removed grafts were analysed with histology, enzyme histochemistry and, in 5 cases, tetracycline labelling. The results demonstrated that the majority (78%) of the grafts consisted at the time of removal of a mixture of living and dead bone. In 13% of the cases there were no indications of bone survival, while 9% of the removed grafts were found to consist of mainly vital bone. It is concluded that the fate of ossicular replacement grafts resembles that previously described for cortical bone grafts used in orthopaedic surgery.