Comparative electron microscopic study of the surface structure of gold, Teflon, and titanium stapes prostheses

Hypothesis: The goal of this study was to compare stapes prostheses of diff erent materials with respect to their surface structures and to discuss the ir suitability for their use in stapes surgery. Background: The surface condition of a stapes prosthesis plays an important role in relation to the type of membrane that forms between the stapes pis ton and the bony edge of the stapedotomy opening. The quality of this membr ane in thickness and mobility is one of the determinants for postoperative hearing improvement. Methods: The surface conditions of gold, Teflon/steel, Teflon/platinum, and titanium stapes prostheses were examined with a scanning electron microsco pe. The loop, shaft, and end of each prosthesis were studied. Results: The gold piston was the smoothest of the four pistons examined. Wh en it was cut with a scalpel, a very smooth surface was achieved at the end area. The Teflon piston had the roughest surface. However, when it was cut , a smooth surface with a parallel arrangement of fibers resulted. Its stee l loop was the smoothest, followed by gold and platinum. The titanium shaft had a scaly surface, which remained when the end of the shaft was shortene d. Conclusion: Because a certain roughness of the piston surface is necessary for the development of a stable membrane between the piston and the edge of the stapedotomy opening, the titanium prosthesis is considered to be the m ost suitable for stapes surgery of the three pistons examined.