Extraoral prostheses include orbital, nasal, and auricular prostheses. An orbital prosthesis artificially restores the eye, eyelids, and adjacent hard and soft tissues lost as a result of trauma or surgery. It serves to restore normal appearance and allow the patient to socially interact with others on a day to day basis. It seals the defect from the external environment and maintains the normal humidity and moisture of the adjacent cavities, i.e. the maxillary sinus, oral and nasal cavities. A nasal prosthesis is fabricated to restore a defect created by the removal of all of the nasal area due to the cancer. It provides normal appearance and serves to maintain normal moisture present in the nasal cavity.
It also assists in maintaining proper humidity and air flow within the nasal cavity and nasal sinuses. Additionally, it may provide support for eyeglasses, when worn and aesthetic and psychological capabilities. An auricular prosthesis is a removable prosthesis which artificially restores all of the natural ear. Its purpose is to restore normal appearance and acts to gather sound waves similar to the human ear, thus aiding in directional hearing. Also, it provides support for eyeglasses, when worn and aesthetic and psychological rehabilitation.
All facial prostheses are made of medical grade silicone and are custom made for each individual patient. For many years, the custom made prosthesis were fabricated by hand and were time intensive. In the past, an impression or mold is made of the defect which gives a model of the defect. Then the next several visits (usually six or seven) are for the sculpting of the prosthesis in wax. This procedure is done by hand and the patient has to be present. Currently, the use of technology is transforming the fabrication process in which the prosthesis is planned virtually (on the computer) resulting in the sculpted prosthesis by rapid prototyping. This results in a 50% reduction in time in the fabrication process. After the sculpting of the prosthesis is finalized, the wax pattern is flasked and then processed in silicone. Finally, the last several visits consist of painting the prosthesis by hand to match the patient’s skin tone. The average longevity of a prosthesis is one to two years. The skin portions are made of silicone, polyurethane or polymethylmethacrylate; the eye is made of acrylic resin or glass. The prosthesis usually is attached by special adhesives (glues) or clips connected to small titanium screws or implants that are implanted into the bone. Placement of osseointegrated titanium screws to retain the prosthesis aids greatly in the retention of the prosthesis. Home care instructions will be reviewed for insertion and removal of the prosthesis and daily care of the prosthesis.