Comparison of biofilm formation on new Phonax and Provox 2 voice prostheses - a pilot study

In voice rehabilitation for laryngectomized patients, voice prosthetic biofilm formation is still an unsolved problem. Design and materials of voice prostheses have been altered by manufacturers to improve function and extend the lifetime of devices. The goal of the study was to investigate biofilm formation on Provox 2 and Phonax, recently introduced voice prostheses made of thermoplastic polyurethane.

Five laryngectomized patients were equipped with both Phonax and Provox 2 voice prostheses. Microbial colonization was analyzed using standard microbiological methods. Biofilm formation and material infiltration were illustrated using scanning electron microscopy, fluorescence microscopy, and thin-section light microscopy.

Although no differences in quality or quantity of microbial colonization were assessed, microscopic imaging revealed differences in material surfaces, biofilm composition, and infiltration morphologies; the polyurethane material seems to destabilize biofilm architecture by inhibition of hypheal Candida growth forms.

Polyurethane material for voice prostheses seems to reduce biofilm stability and infiltrative processes.