Scanning electron microscope and energy dispersive X-ray spectrometry studies on the material surface of extruded Polycel® ossicular prostheses

Abstract

The cause of ossicular prosthesis extrusion remains an issue of interest to many otologists. This study evaluated the change in material surfaces and chemical elements of extruded total ossicular replacement prostheses (TORPs) and partial ossicular replacement prostheses (PORPs). A total of nine extruded Polycel ossicular prostheses (four TORPs, five PORPs) from nine patients was investigated using scanning electron microscope and energy dispersive X-ray spectrometry (EDX). Three prostheses (TORPs) obtained during revision surgery for hearing restoration were used as control subjects for EDX study. All subjects from the study group showed loss of fibrous capsule at both platform and shaft in the extruded prostheses. In comparison with the control group, the extruded prostheses had a lower level of carbon element (Wilcoxon signed-rank test, p < 0.05). Loss of fibrous capsule and micro-degradation are probably two of the many factors that contribute to the extrusion of ossicular prostheses.