Histologic fate of tympanic membrane and ossicle homografts.

1. The biologic behavior and usefulness of homologous incus grafts preserved in Cialit compare favorably with that of ossicular autografts. 2. Reconstruction of the transplanted incus correlates with the period of its immersion in preservative: the briefer the period of exposure to fixative, the more rapidly resorption and substitution occur. The longer the preservation time, the slower the rate of incus transplant reconstruction. 3. The preserved heterograft bone chip is unsuitable, since it disintegrates completely irrespective of the duration of its preservation. 4. The configuration of all bone chips is extensively altered after implantation. Autograft and homograft bone chips are both poorly tolerated. Chemical fixation does not alter this reaction. Fragments are shortened, softened, and rounded off. Heterologous bone chips are completely resorbed.