Anaplastology and facial prosthetics

“The basics”—facial prosthetic rehabilitation

Facial prosthetic devices, such as a nose, eye, or ear, are removable devices that can be worn by the patient daily and removed each night for cleaning and skin hygiene. On average, facial prostheses last 1.5 to 2+ years with regular wear before a replacement is required (depending on the type of prosthesis and retention used). ^, Prostheses can be retained by bar-and-clip or magnet retention systems connected to surgically placed implants with adhesives or by mechanical means (i.e., attachment to eyeglasses). ^, This chapter serves as a primer for physicians in understanding the fundamentals of facial prosthetic rehabilitation as a treatment option, with emphasis on implant-retained devices and surgery ( Fig. 32.1 A, B).

How are facial prostheses made and who makes them?

The process for making a facial prosthesis is highly technical and often requires a substantial amount of time, both clinically and in the laboratory; digital technologies help reduce this time when employed with efficiency. Planning the design for a prosthesis should be considered before any surgery because the outcomes of surgical resection, subsequent reconstruction, and implantation dictate the potential for a successful facial prosthesis. Surgeons who participate in tumor resection or reconstruction of the head and face should be well-versed in facial prosthetic reconstruction as a treatment option for their patients.

The successful prosthetic device is well-planned and designed before surgery. In this way, the anaplastologist can indicate to the surgeon the requirements for the ideal tissue bed, consider retention of the prosthesis, and discuss potential surgical reconstructive options to complement the planned prosthetic design. The typical process for facial prosthetic treatment involves consultation and education; identification of the retention method; definition of the treatment plan and timing of prosthetic appointments; surgical planning (if surgery is anticipated); surgical guide design and fabrication (when indicated); design of the prosthesis by the anaplastologist; fabrication of the device (sculpting, coloration, casting, finishing, and fitting); delivery and education; maintenance; and lifetime follow-up.

How is a prosthesis retained?

A facial prosthesis can be retained with the use of an adhesive or mechanically. The use of an adhesive to retain a facial prosthesis was common before “osseointegration,” which will be the primary focus of this chapter. Today, adhesives are used when a patient is not a candidate for surgical placement of implants or may not be able to manage the lifetime maintenance of percutaneous implants ( Fig. 32.2 A, B).

Retention with adhesives can be very effective if there is a stable tissue bed with limited mobility where the prosthesis will adhere. Gross mobility of the skin, as occurs with facial expression, can cause detachment of the adhesive, which can become problematic for the patient.

Prostheses can also be retained by attachment to eyeglasses; held on with bands, straps, or tape; or retained by engaging naturally occurring undercuts or cavities in the patient’s anatomy. Although there are multiple methods to attach a prosthesis, retention by means of osseointegrated implants offers the most reliable method of retaining a facial prosthesis ^, (see Figs. 32.1 and 32.2 ).

Wearing an implant-retained prosthesis offers certain advantages compared with those retained with adhesives. An implant-retained prosthesis only fits on the patient in one position—an aspect of adhesive retention that often presents a challenge. When adhesive application is not required, the margins (edges) of the prosthesis can be made thinner, providing greater visual integration with the surrounding skin. Retention with implants typically enables the patient to wear the prosthesis for a longer period each day with greater reassurance that the prosthesis will not become loose or dislodged. It has also been reported that patients who wear implant-retained prostheses incorporate the prosthesis into their self-image more quickly through the concept of “osseoperception.” ^, A more detailed discussion of implant-retained prostheses and osseointegration follows.

How long does a prosthesis last?

A prosthesis can last as few as 6 months or as long as 6 years. Compared with an implant-retained prosthesis, an adhesive-retained prosthesis generally lasts for a shorter period due to the daily, manual removal of the adhesives and the solvents required to facilitate this. How long a prosthesis lasts depends very much on the means of retention, how frequently the prosthesis is worn, how well the patient cares for it, the cleanliness of the environment in which it is worn, exposure to the elements, and durability of the material it is made of. Adhesive-retained prostheses have a shorter life, lasting, on average, from 6 months to 18 months, whereas an implant-retained prosthesis has an average expected lifespan of 18-36 months.

Who is a candidate for a facial prosthesis?

When a person is missing a part of the face or head as the result of a congenital condition, trauma, or surgical tumor removal, a removable prosthesis may be a reasonable alternative to surgery. When surgical reconstructive options have been exhausted, the prognosis is poor, or further surgery is not desired, a facial prosthesis can restore the appearance of the patient’s natural anatomy and may contribute to restored function and improvement in quality of life ^, ( Fig. 32.3 A–C).

Who is a candidate for osseointegration?

Most patients rehabilitated by osseointegrated facial prostheses are those with head and neck cancer. Another growing population comprises patients with congenital microtia, when autogenous reconstruction is unsuitable or has proven unsuccessful. Survivors of trauma, including motor vehicle accidents and burns, are also typically ideal candidates for osseointegration. Successful rehabilitation with osseointegration requires the presence of viable bone in the area of reconstruction and a good surgical candidate. Some relative contraindications include smoking, previous radiation therapy, religious beliefs, or lack of psychologic readiness. However, a patient is not automatically excluded from surgery for placement of implants even under these circumstances. Many patients who have undergone radiation therapy, for instance, have successfully worn implant-retained facial prostheses for many years. Additionally, adjunctive therapies, such as hyperbaric oxygen (HBO), have been employed on the presumption that it contributes to improved implant survival; however, there is some controversy over the use of this treatment. ^,

Education—managing realistic expectations

It is essential that the patient and the family are well informed and educated on the options before pursuing this treatment. Maintaining realistic expectations of prosthetic reconstruction throughout the treatment process is crucial to the patient’s overall rehabilitation because treatment can be lengthy and has inherent technical limitations. Often, psychology teams are engaged early in the treatment process to assess the patient’s understanding of what is possible and to gauge the patient’s and the family’s expectations of the final outcomes. Prosthetic rehabilitation requires a substantial commitment on the patient’s behalf, not only to endure the initial reconstructive treatment but also for lifetime maintenance, as prostheses are temporary devices with a relatively short lifespan and require regular replacement through the patient’s lifetime. Having a strong, positive, and supportive network of family, friends, community, and other care providers contributes substantially to a patient’s prosthetic rehabilitation.

It is important that the patient, the family, and the care providers alike recognize and accept the limitations of prosthetic devices. At the time of this writing, prostheses are primarily artificial static devices that provide limited anatomic and physiologic functions and contribute more to psychosocial function and quality of life. ^, For example, at present, an oculoorbital prosthesis will not blink or move, although many research teams have pursued movable prosthetic designs. Prosthetic devices, such as intraoral or internal devices—obturators, palatal lift devices, dentures, stents, heart valve replacements, and limb prosthetics—provide clear functional, anatomic, and physiologic benefits; however, facial prosthetic devices provide function by holding up eyeglasses in the case of a prosthetic nose or ear, or by securing a stethoscope or surgical mask in the case of a prosthetic ear. A prosthetic nose or orbital prosthesis provides a barrier for mucosal tissue protecting it from external debris and also aids in keeping sensitive tissues moist in internal cavities. Current understanding of quantifiable physiologic functional gain is limited, although researchers have explored this. More often, psychosocial function, which also can be difficult to quantify, and improvement in quality of life have been extensively described as important motivators in recommending or pursuing facial prosthetic treatment. ^{, , ,}

It is important that referring specialists are careful not to overinflate a patient’s and/or family’s expectations from prosthetic reconstructive treatment. In spite of a surgical service’s access to highly skilled anaplastologists, comments made to the patient and the family in an attempt to encourage, such as “They are so natural looking,” or “No one will ever know the difference,” can create unachievable expectations, compromising a patient’s rehabilitation potential and acceptance of the prosthesis.

History

A thorough medical history and physical examination should be performed at consultation to identify the full scope of the patient’s rehabilitative needs so that the patient can be referred to the appropriate specialists and treatment can be coordinated to address all of the clinical needs in a comprehensive manner. Facial prosthetic patients are often seen by a complement of multidisciplinary specialists, including an oncologic surgeon, a reconstructive surgeon, a craniofacial surgeon, an otolaryngologist, an audiologist, an anaplastologist, a psychologist, a maxillofacial prosthodontist, an orthodontist, an ocularist, a speech language pathologist, a genetic counselor, and other specialists, as indicated.

Besides assessing for general medical and mental health, healing and recovery from surgery, adjuvant therapies, and skin allergies, the patient should be assessed for ability to manage the daily placement, removal and cleaning of the prosthesis, general hygiene, claustrophobia (if physical facial impressions are indicated), social history (including smoking), vision, manual dexterity, and some aspects of daily home and work life, including availability of a support network. Manual dexterity and absence of hand/arm tremors are also important considerations for the patient’s ability to manage the daily placement, removal, and cleaning of the prosthesis.