Steinbach in the 1990s introduced pistons made of pure gold that have a soft band that can easily be pressed onto the incus process. Particularly popular among ear surgeons is the stapedotomy technique developed by Fisch, who was using the fine 0.4-mm metal wire-Teflon piston, and later platinum band-Teflon piston. The possible gap around the prosthesis was filled by blood clots, Gelfoam, connective or adipose tissue. Since these piston prostheses fitted the small footplate perforation exactly, some surgeons also dispensed the use of a vein, fascia or adipose tissue graft to cover the fenestra. Thanks to the small diameter of a piston, it became possible to reverse the classic stapedotomy steps in the way that the footplate was perforated first and the fine piston was inserted while the stapes structure was still present and fixed to the incus process. While initially the diameter of pistons used was 0.8 and 0.6 mm, from the 1970s onwards, it has been becoming even smaller, i.e. He also refers to the footplate hole diameter, which should be 0.7 mm, so it would not touch the annular ligament but is not too small to transmit sufficient energy either. The piston penetration should not exceed 400 |xm. Furthermore, the prosthesis should protrude a little into the vestibule because otherwise a fibrous layer from the graft can involve the extremity of the prosthesis and cause bad functional results. It is very important that nonwettable materials (like Teflon) should be used for prostheses due to the phenomenon of surface tension. Marquet, in his stapedotomy review article, pointed out that there are many factors that influence the success of the procedure. The prefabricated, commercially available piston prostheses replaced the intraoperatively prepared wire prostheses which were made individually by the surgeon at the operating table, in order to simplify the operation, save time and ensure a standard quality. From left to right: Fisch Teflon platinum 0.4-mm piston, Teflon wire 0.6-mm piston, gold piston, wire prosthesis.Įntirely of stainless steel and fastened to the incus process at the top with a handle.
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