The authors designed and made a prosthesis for total replacement of the middle ear ossicular chain (TORP) from Silastic MDX 44-516. A great advantage of this substitute is that it can easily be modified to a prosthesis for partial replacement of the middle-ear ossicular chain (PORP). The transfer properties of the PORP type prosthesis were verified by using an electroacoustic model measurement. Very good anatomical and functional results were obtained in the clinical testing of both types of middle-ear substitutes. No undesired reactions to the implanted polymer were observed.