Biofilm formation by Pseudomonas aeruginosa on ossicular reconstruction prostheses.

ABSTRACT

PURPOSE: Ossicular chain reconstruction may be complicated by prosthesis extrusion. As prostheses are commonly placed in middle ears contaminated with biofilm-forming bacteria, such as Pseudomonas aeruginosa (PA), extrusion may be caused by development of a biofilm on the prosthesis and the host response to this biofilm. The purpose of this experiment was to determine if PA forms biofilm on different ossicular chain reconstruction prostheses to a different degree. METHODS: Prostheses made of titanium, hydroxylapatite (HA), and plastic (23 each) were cultured with PA in broth for 96 hours. Biofilm formation was assessed by electron microscopy and quantitative microbiology. RESULTS: Titanium prostheses formed less biofilm than plastic (P = .0003) and HA (P = .003), but there was no difference between HA and plastic. Correction for surface area did not alter these significant differences. CONCLUSIONS: Pseudomonas aeruginosa forms biofilm on ossicular prostheses, particularly those made of plastic and HA. These differences could, in part, explain the extrusion propensity of certain biomaterials.