Functional and structural aspects of tracheosophageal voice prostheses

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The artificial throat:A new method for standardization of in vitro experiments with tracheo-oesophageal voice prostheses

After total laryngectomy, the voice can be restored successfully with a silicone tracheo-oesophageal voice prosthesis. Biofilm formation and subsequent deterioration of the silicone material of the prosthesis often limit the mean life of the device to an average of 3-5 months. Although device replacement can be considered an easy outpatient procedure. frequent replacements are inconvenient for the patient and may lead to malfunction of the tracheo-oesophageal fistula. Further understanding of the process of development and inhibition of the colonization of these polymer surfaces requires several comprehensive clinical studies. How ever, iii vivo research of the biomaterials of the voice prostheses is difficult and time consuming. In order to simulate the natural process of biofilm development under dynamic nutrient conditions, an artificial throat was developed. Biofilm developed on Groningen(R) button voice prostheses iii vitro a could not be distinguished from that formed over several months in,vitro. This method can be used as a standardized approach for studying functional and structural aspects of all commercially available indwelling and non-indwelling voice prostheses, including the Groningen(R) button, Provox(R), Voice Master(R), Blom-Singer(R) and others under various laboratory conditions

Biofilm formation and design features of indwelling silicone rubber tracheoesophageal voice prostheses - An electron microscopical study

After total laryngectomy, voice can be restored with a silicone rubber tracheoesophageal voice prosthesis. However, biofilm formation and subsequent deterioration of the silicone material of the prosthesis will limit device life by impairing valve function. To simulate the natural process of biofilm development under dynamic nutrient conditions, a modified Robbins device was used to evaluate the biofilm-related valve dysfunction of the Groningen, Provox2, Blom-Singer indwelling, and VoiceMaster voice prostheses. Obstruction of the semicircular slit-valved Groningen prosthesis leading to increased airway resistance was caused not only by a buildup of deposits on the esophageal flange and valve hat, but also by accumulation of deposits on the semicircular valve seating. The hinged flap valved Provox2 and indwelling Blom-Singer prostheses failed to close sufficiently because of biofilm formation on the valve seating. The esophageal flange of the VoiceMaster prosthesis was affected, but the tripod structure of the ball valve was fully colonized up to the titanium sleeve, which interfered with proper valve opening and closure. These findings on biofilm formation could be used for the further development and modification of critical design features of voice prostheses to facilitate tracheoesophageall speech. (C) 2001 John Wiley & Sons, Inc