**7.3. Prosthesis infiltration**

3D printing produces models with excess powder intimately associated with the final struc‐ ture. The resultant powder has to be gently removed prior to infiltration with a suitable material. The prosthesis can then be immersed into the infiltrant either with or without the infiltration base and a period of time allowed for complete saturation. This process will be dependent on the thickness of the printed model and viscosity and setting characteristics of the infiltrant. All will have to be evaluated prior to production of the definitive prostheses. Ideally, materials with characteristics and properties close to those used in existing production methods should be utilised in order to make a comparable prosthesis. Normally, the materials employed would be either silicone, acrylic or polyvinyl in nature. Given the variability in the characteristics of these materials extended periods of immersion or infiltration under pressure may have to be considered. Following this process, excess infiltrant needs to be removed from key areas such as the apertures, orifices and attachment housings, and then allowed to fully cure and dry. This process normally takes approximately 24 h.

**Figure 10.** Photograph of a 3D printed nasal prosthesis infiltrated with a compatible medical grade silicone infiltrate (Approx. part Dim: 40 × 24 × 25 mm).
