[Are cialit-preserved ossicles as middle ear implants still bacteriologically defensible? Their replacement by pre-formed implants fashioned from teeth].
Recent studies have demonstrated a limited bactericidal activity of Cialit in the preservation of otologic transplants. The authors therefore performed several tests following routine treatment of the grafts. First, the contamination of allogenic ossicles was studied; afterwards, the bactericidal activity of Cialit was tested against standardized germs and clinical isolates. At the highly toxic concentration of 1:2000, Cialit is bactericidal. For clinical purposes, however, the less toxic solution of 1:5000 is generally used, which is not sufficiently safe against certain resistant clinical isolates. The fact that the activity of Cialit depends on its concentration explains the controversial findings in the literature. Furthermore, it is doubtful whether a weaker solution would prevent transmission of an HIV or hepatitis infection. Therefore, the authors recommend the autoclaving of otologic allografts. This also has forensic reasons; for example if the serologic status of the donor is unknown. As ossicles become brittle under this procedure, the authors now use sculptured parts of teeth, in which the hydroxyl-apatite is much more compact. The preformed prostheses can be autoclaved without problem. More than 150 reconstructions have proved the acceptance of this cheap implant material. Furthermore, forensic problems with ossicles from corpses do not arise.