Effect of dairy products on the lifetime of Provox2 voice prostheses in vitro and in vivo

Background. Reduction of biofilm formation on tracheoesophageal voice prostheses by certain dairy products might extend their clinical lifetime. The purpose of this study was to determine the influence of certain dairy products on voice prosthetic biofilms and lifetimes in vitro and in vivo.Methods. The in vitro results were accomplished using an artificial throat. The lifetimes of Provox2 prostheses were evaluated in a patient group that daily consumed the evaluated products.Results. Buttermilk and Yakult Light fermented milk decreased the amount of bacteria on voice prostheses but stimulated yeast prevalence in vitro. Concurrently, lifetimes of voice prostheses in patients consuming buttermilk were not significantly different, whereas patients consuming Yakult Light fermented milk drink had a significantly (p <.01) increased prosthesis lifetime by a factor of 3.76.Conclusion. Yakult Light fermented milk drink reduced biofilm formation on Provox2 prostheses in vitro and in vivo and significantly increased prosthesis lifetime. In vivo, no significant effects were observed for patients consuming buttermilk. (c) 2005 Wiley Periodicals, Inc.