Ocular and Maxillofacial Prosthetics: A Brief History
The Archeological History of Ocular and Maxillofacial Prosthetics
Throughout recorded history, it is evident that man has found a need to attempt to restore or replace the eyes and facial parts of those who were either unfortunate enough to have congenital deformities, or to have suffered from trauma or the disease processes of later life. Most of the evidence of the evolution of ocular and facial prosthetics until the mid 16th century is anecdotal. The record of the origin of ocular and facial prosthetics until the middle of the 16th century is more accurately an archeological record of the artistic ability and technology available to those who attempted to replace facial parts. Even so, a few examples of the artists’ attempts to deal with facial deformity have been found that give us a glimpse of the use of ocular and facial prosthetics by early civilizations and their methods of fabricating them.
Egyptologists have recovered the earliest fragments of information that we have to rely on. During the evacuation of the burial tombs of the elite in this society, it was found that the bodies had been preserved for use in their next life. Research into the methods employed in mummification has shown that an important part of the process came to be the replacement of the eyes of the person being mummified, in accordance with religious tenants. Reisburg and Habakuk state that “radiographs of mummies confirm the presence of radiopaque objects in the orbital areas that resemble eyes.”
“Mud was packed under the skin and linen cloth was placed in the mouth to restore facial contours. Artificial eyes of earthenware, precious stones, and enameled bronze, copper, and gold were placed in the shrunken sockets” (Reisburg and Habakuk 12). This postmortem replacement of the eyes and reconformation of the facial features can be argued to be the beginnings of the technology necessary to replace the lost facial features of the living.
During the same period, it is reported by Valauri that “archeological excavations of tombs pre 2,500 BC have illustrated material found in carvings, sculptures, which provide evidence of fabrication of nasal, orbital, auricular prostheses, and dental restorative treatment being carried out” (Valauri 243. The use of the same natural materials by other civilizations in later periods include the early Chinese dynasties: “historians and archeologists have reported the discovery of facial prostheses fabricated in wood, wax, and clay in the tombs of the early Chinese period” (Valauri 243) and later during the “Greek and Roman period (1,000 BC.) [there were] artificial eyes of quartz, rock crystal, and enamel made from statues (Valauri 243).
The earliest accounts of the use of facial prosthetics in living humans included those by Dyer who “related accounts where ocular prostheses were reportedly worn by individuals during life.” He referred to “Egyptian priests in 500 BC who fabricated artificial eyes from earthenware [that were] constructed so that the eye and lids were incorporated as a single unit attached to flesh colored cloth and fixed in place over the socket” (Reisburg and Habakuk 12).
The Recorded History of Ocular and Facial Prosthetics
It is believed that “The first well-documented account of facial prosthetics is provided by Ambroise Pare (1509-1590), a French military surgeon of great ability who made many and varied contributions to the development of surgery-no doubt the father of ‘facial prosthesis.’ ” (Valauri 244). Dr. Pare did much to standardize the indications for and materials used in facial prosthetics.
Since this time, many accounts of ocular and facial prosthetics have been recorded. Both the common and the famous have achieved notoriety as a result of their facial injuries. Their stories give us a reasonably good view of the historical progression of prosthetics from an art, to a combination of art and science. Among the more notable persons to have had a facial trauma restored by earlier prosthetic means was Tyco Brahe (1546-1601,) the famous Danish astronomer. An account of the time states that “on the 29th, at seven o’clock in the evening, in perfect darkness, [Tyco Brahe and Manderup Parbjerg] settled their dispute with swords. The result was that Tyco lost part of his nose, and in order to conceal the disfigurement, he replaced the lost piece by another made of a composition of gold and silver” (Valauri 246). Another slightly later event in 1883 brought a French private who was injured in the siege of Antwerp to the attention of the medical community. This private known as the “Gunner with the Silver Mask” had the majority of the lower portion of his face avulsed by a large shell fragment. A silver mask was fabricated to disguise the defect as well as to provide anatomical support for the tongue and for collection of secretions. The mask was described in the London Gazette as:
“Half mask, without nose or cheeks, that enclosed the whole extent of the edges of the contrivance, where they came in contact with the face, were skillfully obscured by mustachios and whiskers, and it was fortunate that these were the fashion of the day. The external aspect of the mask was painted in oils so as to correspond with his complexion, and it is said that the illusion was so strong that ‘unless forewarned, he might be steadfastly examined at a short distance without betraying his misfortune.’” (Valauri 247)
This case indicates that the importance of functionality, as well as cosmesis, was beginning to be recognized by those who were making prosthetics at the time.
In Europe, the art of fabricating artificial eyes took a great leap forward from the use of metals, ivory, and clay. This leap took place when Laurent Hiester, a German surgeon, suggested in 1752 that the “use of glass rather than metal eyes, since glass could be better tolerated by orbital tissues” (Danz Sr. 2). Glass came to become the material of choice for ocular prosthetics worldwide for the next two hundred years. The techniques for making the glass stock, as well as for the fabrication of the glass ocular prosthesis, evolved into a highly refined art limited in its approximation of the cosmesis of the eye and the anatomical relationship to the orbit only by the limitations of the material itself. The greatest of these limitations was the inability to approximate the surface irregularities of the anterior surface of the posterior orbit. Another was the fragility of the glass and its propensity to fracture in orbit.
An 1869 text entitled Diseases of the Eye, published in the United States, describes the “state of the art” with great respect. “These substitutes for one of the most expressive of the human features have been brought to a beautiful perfection” (Williams 234). It goes on to indicated the origin of the prostheses in use at the time in the U.S.. “Most of those in use are of Paris manufacture, though a few are made in this country” (Williams 234). This same period, though, saw a migration of the apprentices of Europe to the United States where in a very short period of time, a domestic capability to produce prosthetics of suitable quality was established.
The Recent Past
The last fifty years has seen marked improvements in the field of ocular and facial prosthetics. The most significant advances have been made in materials science and integration of the prosthesis with the hard and soft tissues of the body. The impetus for these improvements came as it often does from the country being at war. During World War II, the specialized glass compounds that were normally imported from Western Europe were unavailable, and the closely guarded trade secrets of their manufacture made it all but impossible to recreate them of sufficient quality in the United States. As a result, the medical departments of the Army and the Navy began to do research into the use of a new material that was being introduced into the medical, and especially the dental community. It was called Poly-Methyl-Methacrylate Acrylic (PMMA) (Danz 4). This material was found to be superior to glass for use in ocular prosthetics in that it could more easily be made into the shape of an impression that was taken of the posterior section of the anophthalmic orbit. This had previously been one of the limitations of glass for ocular prosthetics. Information on the use of this new material was disseminated, and after great debate amongst the “new” plastic and “old” glass ocularist, it became evident that there was no question as to the superiority of the material. Glass prosthetics were to be used only by those who had a true allergy to acrylic. The last person in the United States who practiced the art of “glass blowing,” Earl Schribner, died in 1992, and the practice was taken over by his daughter who works only in acrylic. The art of blowing glass artificial eyes in the U.S. is now lost.
During this period, materials were also introduced which advanced the state of the art in facial prosthetics. The two improvements, which were most notable, have been elastomers, known as silastics, for the formation of the body of the prosthesis, and titanium implants placed in the bone for the retention of the prosthesis (osseointegration.) An example of an orbital exenteration that has been restored through the use of silastics and osseointegration implants can be seen in Fig. 3. The quality of the cosmetic result and the ease of use that the magnetic attachment to the titanium implants create for the patient make this prosthesis almost perfect. Its one downfall is a lack of motility in the eye and lids.
In the 1950’s there was a greater need for prosthetics than there were qualified persons to make them. This was especially evident in medically under-served areas. As a result, several companies began to produce “stock” ocular prosthetics. A text written in 1957 alludes to the ordering of a “stock” prosthesis. This practice is no longer in use as it retained the limitations in fitting that were part of the “glass” tradition. The author stated that “if an artist familiar with artificial eye practice cannot be engaged, the practitioner should either use a series of artificial eyes or a specially designed set of templates for the exact cosmetic lens specifications” (Bier 122).
Other aspects of the field were also evolving at a great rate as a result of the use of PMMA. The improved technique allowed for greater transference of residual motion retained in the orbit through the interaction of specially shaped implants. “The past 30 years has witnessed the production of many types of intraorbital implants composed of varied materials. Types include spheres, buried implants, semiburied implants, magnetic implants, and two part implants, all of assorted shapes and designs” (Soll, 287). Some of these implants were to find acceptance during this period, but the majority of them suffered from complications, which precluded their use. Eventually, all of the motility implants from this generation were found to be contraindicated, primarily due to high incidences of infection due to their design. It was not until the late 1980’s when the Perry hydroxyapatite motility implant was introduced that an implant could be safely integrated with the artificial eye. This left the lack of dilation of the pupil of the artificial eye as the only other variance from a normal cosmesis by the prosthetic wearer. This problem has been rectified through the “Photochromic Dilating Pupil for the Ocular Prosthetic” (appendix).
The Future of Ocular Facial Prosthetics
Basic clinical research and work in the anophthalmic socket has been directed in four main categories: (1) development of new types of intraorbital implants; (2) correction of long term complications; (3) improvement of the prosthetic design and construction; and (4) advances in surgical techniques” (Soll 283). Where the future will lead, one only can guess. Several projects are underway at present, the most important of which may be the Sighted Ocular Prosthesis Project at the National Institutes of Health. This project is attempting to give at least some form of vision to the profoundly blind through the use of an optical sensor, a processor, and a direct visual cortex stimulation.