Comparison of the microbial composition of voice prosthesis biofilms from patients requiring frequent versus infrequent replacement

This study was performed to establish a possible difference in biofilm composition in patients who require frequent versus infrequent prosthesis replacement. Only Groningen button voice prostheses that were removed because of increased airflow resistance or leakage of food or liquids through the prosthesis were considered for this study. These prostheses were selected from a total of 692 failed voice prostheses over a 2-year evaluation period. The failed voice prostheses were subdivided into a short-lifetime group, corresponding to an implantation period of less than 4 months (20 voice prostheses), and an extended-life time group, cor-responding to an implantation period of greater than 9 months (18 voice prostheses). The biofilm was removed from the valve sides of the prostheses. The bacterial strain Rothia dentocariosa and the yeast strains Candida albicans I and Candida tropicalis were the predominant strains isolated from the biofilms on the voice prostheses in the short-lifetime group, whereas in the extended-lifetime group, R dentocariosa was found with a fourfold lower isolation frequency and C albicans I was found with a twofold lower isolation frequency. Candida tropicalis was absent from the extended-lifetime group.