Summer 1997
Sometimes a person's ability to speak, swallow or chew depends on maxillofacial prostheses—artificial parts for the face area—such as those fabricated by Mark A. Pigno, DDS, assistant professor of prosthodontics and director of the Health Science Center's Maxillofacial Prosthetics Tertiary Care Center. In other instances, a prosthesis may be needed for cosmetic reasons—perhaps a cancer patient has lost an eye, an ear or a nose.
"Reconstruction—using the patient's own tissue—is always the first choice," said Dr. Pigno. "Prosthetics are involved only if surgery can't obtain the desired results. Our job is to support the surgeon any way we can."
To create a facial prosthesis, an impression of the defect is made, like a negative of the patient's face. That negative is used to make a model of the defect, then a prosthesis to correct, conceal or compensate for the defect is sculpted in clay or wax. "We try the sculpture on the patient to be sure it's right," said Dr. Pigno. "If it looks good, we use silicone or other rubbery material to make the prosthesis, and color it to match the patient's skin. Adhesive is used to bond the prosthesis to the skin.
"A well-made prosthesis blends really, really well. You won't see it on casual observation. You have to look very closely," said Dr. Pigno.
The normal life span of most prostheses is from six months to two years, or less if the patient smokes. Then it has to be remade. "The margins become old from handling, or different types of fungi and bacteria cause discoloration," said Dr. Pigno. "Or UV light from the sun degrades the silicone over time."
A recent advancement has helped prostheses such as ears stay in place, explained Dr. Pigno. "Craniofacial implants (small titanium screws) are placed in the bone by surgeons and allowed to heal for three to six months," he explained. "Then we uncover them and use the implants to hold the prosthesis in place. Without implants it would be very difficult for some prostheses to stay put—use of implants for retention increases their stability. For instance, some dentures aren't stable, and some ears won't stay glued to the side of the head."
Use of craniofacial implants for retention of facial prostheses in adults is becoming more widely accepted but they must be used with caution in children, according to the prosthodontist. "We really don't know the effects of implant placement in the craniofacial region of a growing child—there hasn't been enough research done," Dr. Pigno said.
Serving San Antonio and South Texas, the center's staff includes a medical sculptor and a maxillofacial prosthetics laboratory technician. Primarily the center fabricates special prostheses for head and neck conditions resulting from cancer, trauma or birth defects.
It also has fashioned finger prostheses. "One patient put his hand in the wrong place when an electric gate opened, and it severed the end of his left middle finger. He was treated by a plastic surgeon and then referred to us," Dr. Pigno said. "The digital prosthesis replaces a missing body part, and it helps to give the patient opposition for his other fingers. It also protects a sensitive area and helps during writing, typing and other activities by restoring the proper length to the finger."
While still in college Dr. Pigno saw the devastating results of all types of cancer. His father was ill with the disease and hospitalized at The University of Texas M. D. Anderson Cancer Center in Houston. "Now I can help others—perhaps give back to another patient for the wonderful care he received.
"It's gratifying to be able to restore some dignity to these patients," Dr. Pigno added, "and to help them remain functioning members of society." An electric gate severed the end of this patient's left middle finger. Mark A. Pigno, DDS, developed a finger prosthesis. Medical sculptor Ralph (Monty) Montalvo will match the patient's skin tone to the prosthesis.
