Testing has shown that to optimise the performance of the device, comfort and fit, Turbine should be replaced after 10 uses. While Turbine may appear fit for use beyond 10 uses, optimal device performance cannot be guaranteed because: 1. Of the risk of bacteria accumulation and the maintenance of hygiene standards. 2. The device may discolour or the ultra-soft polymer may begin to stiffen affecting comfort. 3. The dilation mechanism will wear and may not hold its dilation effectively.