Journal of Dental Research and Review

REVIEW ARTICLE
Year
: 2022  |  Volume : 9  |  Issue : 2  |  Page : 85--94

A comprehensive review of extraoral maxillofacial material: Part I


Darshana Choubisa 
 Department of Prosthodontics, Geetanjali Dental and Research Institute, Udaipur, Rajasthan, India

Correspondence Address:
Darshana Choubisa
Department of Prosthodontics, Geetanjali Dental and Research Institute, Udaipur, Rajasthan
India

Abstract

Recently, the use of extraoral maxillofacial materials for prosthetic rehabilitation of lost facial structures due to trauma, surgical resection, acquired infection, congenital abnormalities, and burns has heightened dramatically. Extraoral maxillofacial materials have contributed sufficient resolutions in conditions where thorough surgical techniques leave sizable facial defects that jeopardize function and esthetics or situation where surgical reconstruction is contraindicated. At the moment, no ideal extraoral maxillofacial materials have been developed that can mimic human skin. Each material has its own advantages and disadvantages. This article is a comprehensive review done in an attempt to present an overview of the extraoral maxillofacial materials used in the maxillofacial prosthodontics. A computerized exploration was conducted to extract articles using keywords facial defects, extra oral maxillofacial material, maxillofacial rehabilitation, prostheses from PubMed, Scopus, Web of Science and Google Scholar. This article has been divided into four parts. Part I dealt with historical background; Part II dealt with review of some early extraoral maxillofacial materials; part III dealt with majorly with silicone elastomers as an extraoral maxillofacial material; and part IV dealt with recent advances.



How to cite this article:
Choubisa D. A comprehensive review of extraoral maxillofacial material: Part I.J Dent Res Rev 2022;9:85-94


How to cite this URL:
Choubisa D. A comprehensive review of extraoral maxillofacial material: Part I. J Dent Res Rev [serial online] 2022 [cited 2022 Oct 7 ];9:85-94
Available from: https://www.jdrr.org/text.asp?2022/9/2/85/354195


Full Text



 Introduction



In the present aeon, physiognomy has become substrate for contentment, compared to the caliber of personality and intelligence. It has become salient yardstick for nuptials, employment and accomplishment. Hence, facial imperfection due to trauma, surgical resection, acquired infection, congenital abnormalities, and burns immensely affect not only function and esthetics but also the existence of patient's caliber, as they continuously remind of their malady.[1],[2]

Neoteric advances in maxillofacial prosthodontics have increased demand for prosthetic rehabilitation of patients with facial defect either surgically or prosthetically. However, maxillofacial surgical reconstruction is often contraindicated in the presence of sizeable deformity, poor blood supply on the post radiated tissue, advanced age of the patient and poor health. Often, in many cases, maxillofacial surgical reconstruction is exigent and also arduous to accomplish acceptable outcome. Therefore, prosthetic rehabilitation offers the advantage of expeditious, reversible and medically straightforward rehabilitation. Adjunctively, the maxillofacial prostheses can be effortlessly detached to enable assessment of the health of underlying tissue.[3]

A maxillofacial prosthesis is any prosthesis used to replace part or all of any stomatognathic and/or craniofacial structures.[4] Various factors determine the success of an extraoral maxillofacial prosthesis: durability, biocompatibility, resilience, weight, color, cleanliness, thermal conductivity, easeful, characteristics, and availability.[5],[6] Hence, selection of bona fide extraoral maxillofacial material has become more paramount in maxillofacial rehabilitation. Alter in exploration and burgeoning demand has led to the exploration for more acceptable extraoral maxillofacial materials for maxillofacial prostheses in past several decades, often the standard of prostheses remain less than satisfactory.

This article is a comprehensive review done in an attempt to present an overview of the materials used in the extraoral maxillofacial prosthodontics. This article has been divided into four parts. Part I dealt with historical background; Part II dealt with review of some early extraoral maxillofacial materials; part III dealt with majorly with silicone elastomers as an extraoral maxillofacial material; and part IV dealt with recent advances.

 Desirable Properties



Broadly, there are five requisites which determine the desired properties of the ideal extraoral maxillofacial material: (1) forestall additional tissue loss; (2) lasting in appearance, elasticity, color, and texture; (3) to discern and appear more realistic; (4) easy to hold in position; and (5) improves the patient's self-confidence.[7]

In 1990s, Andres and Beumer delineated the ideal properties of maxillofacial prosthetic material:[5],[8],[9]

Ideal physical and mechanical properties-

High tensile strengthHigh tear strength (approximately 30–100 psi)High elongation strength (modulus at 100% elongation, approximately 50–250 psi and elongation at break, approximately 400%–800%)High tensile strength (approximately 1000–2000 psi)Glass transition temperature, <0°CHeat distortion temperature, more than 120°CHigh resistance to abrasionHardness approximately 25–35 Shore A scaleLow coefficient of friction (approximately 0.4–0.6)Variable consistencyLow specific gravityAllows detail reproductionLow surface tension (critical being approximately 30–45 dynes/cm)Low thermal conductivityFlexible at a temperature range from 44°C to 60°C and flexibility to approximate the mechanical properties of the natural tissuesNon inflammableNo water sorptionLight in weightOdorlessTranslucent

Ideal processing characteristics:

Viscosity at ambient temperature, <75,000 cpsSolubility parameter, approximately 9–11 Cal1/2Chemically inert after processingFidelity of detail reproductionEase of intrinsic and extrinsic coloringSufficient working time (Pot life, approximately 15–60 min)Dimensionally stable during and after processingNo color change after processingEase of mold fabrication and processingAdjustabilityPolymerization should occur at a low temperature so that molds can be reused (curing temperature, approximately <100°C and curing time, approximately 1–2 h)Blending of individual components should be easyEase in making duplicates or replacements, if needed

Ideal biological properties:

BiocompatibilityNonallergic, noncarcinogenic and nontoxicCleansable with disinfectants without loss of surface and marginal detailsColor stable on exposure to environmental aggressions like ultraviolet rays, oxygen, secretions, oils and adhesives and their solvents or under ordinary weathering conditionsPassive to solvents and skin adhesiveMicrobial resistanceMaintains softness during usePermeable to moisture release from underlying tissues.

Ideal esthetic properties:

It should be able to accept colors and shades to simulate the patient's skin characteristics. Its texture, shape, color, and translucency should replicate lost anatomy and the adjoining tissues, creating lifelike prostheses.

Others

Sustainable longevity of final prosthesis should preferably be minimum of 1–5 yearsTo perpetuate longevity, final prostheses should have the ability to reline and readapt to the tissues enclosing the flaw.

 Historical Development



It is a venture to explore and report the historical development of extraoral maxillofacial materials used in rehabilitation of maxillofacial region. Moreover, exploring and communicating past information helps avoid duplication of procedures and use of materials that others have previously found dissatisfying.

3000 BC

Studies by clinicians and prosthetics have depicted many quotations that indicate that maxillofacial prostheses were contrived in Egypt, Ur, and Babylon.[10]

According to Egyptian religion belief, the eye was considered as an emblem of existence in the primeval time and the soul of the dead returned to the body, therefore, Egyptian priests, following removal of the eyes of their dead, filled the orbit with wax or plaster and simulated the iris with precious stones.[11] Roentgen rays of eye sockets of unwind mummies had shown metallic shells. Between the 20th and 21st dynasties, for a more realistic appearance, mortician began installing metallic shell-like orbital conformers that were glazed to simulate the shade of the eyes of departed with bronze eyelids, as reported by Grays. The British Museum had display cases of such mummified body from Rameses III and other with “artificial eyes” installed. The Egyptian burial sites, also imitated the structures of the nasal and auricles, installed after death in order to correspond to the cult.[12],[13] Around this aeon, a similar corroboration of timber, wax, and kaolin artifacts that simulate anatomy is available when digging graves in China.

Indeed, in the Babylonian aeon, there was a degree of civilization and artisans that has “technical artistry” to make prosthesis, especially with gold. They also used enamel to simulate skin tones.[13]

1500 BC

The Romans differentiated betwixt the Medicus Ocularius and the Faber Ocularius. Medicus Ocularius was medical care in-charge, while Faber Ocularius was for construction and adaptation of eye prostheses and prostheses fabricated by them had an extremely realistic appearance and their shape seems to have comfortable wearable shapes.[14]

1000 BC

Many gold and silver face masks were excavated from cemeteries in the Thracian period in what is now Bulgaria.[13]

200 AD

Popp, a German medical researcher, reported the first reference to maxillofacial prosthetic rehabilitation that was actually carried out in this millennium. In 1939, he published an article referring to the discovery of evidence that prostheses based on a metallic scaffold with unknown elemental source and covered outside with a coat of varnish resembling facial skin tones were made in China around 200 AD.[15]

Back in Greece, archaeologists delineated discovering abode moldings, simulating human noses, eyes, ears.[13]

600 AD

The only known episode of prosthetic rehabilitation betwixt 200–1000 AD, refers a Byzantine ruler, Justinian who wore a nasal prosthesis (“golden nose”), after publicly suffered from “rhinoscopy” and glossotomy.[16]

1000 AD

Two cases of prosthetic rehabilitation have been recognized. The first case concerns the German Emperor, Kaiser Otto III, wearing a “golden nasal prosthesis” to disguise a nasal defect reported by Paschkel.[13],[17] Another case demarcated by Lufkin, speaking of Abulcasis of Cardova who knew “craft and form” of ivory based facial prostheses.[18]

1500 AD

The first scholarly proclamation on the practice of extraoral maxillofacial prosthodontics is in the compositions of a French military surgeon, Ambroise Pare (1507–1590), known as “no mean engineer.” No doubt he was regarded as innovative surgeon and engineer since his memoir of 1579 and described numerous surgical procedures advanced of their time, as well as proposals concerning the feasible layout of body, face and eye prosthesis.

Introduced a lot of simple prosthesis which were used for the esthetic and functional rehabilitation of lost maxillofacial structures. He fabricated facial prostheses from the following materials: Papier-mâché (linen), leather, ivory, gold, and silver. Pare also advocated those nasal prostheses can be restrained either by a sticky substance (probably gum mastic) or by means of three strips of linen placed on the patient's cranium and ear with a metal band. He is accrediting with being the first acclaimed personage to delineate the viability of a prosthetic rehabilitation of lost eye. He mentioned two types of prosthetic eyes: (i) Hyplepharon (a lingering or artificial eye) and (ii) Eclepharon (eye/facial prostheses placed outwardly).

The intrinsic eye prosthesis, which are said to have been made by Ambroise Pare at the time, was fabricated from two identical convex shaped gold/silver sheets that were fasten to create a form simulating an orbit, followed by coating of exterior with an enamel coat and staining to simulate tiny blood vessels and the sectioning of the iris and pupil.

On the report of Beder, the first obturator was described by Ambroise Pare in 1541, consisting of a simple disc attached to a sponge. The sponge was inserted into the defect and swelled from secretions by absorbing moisture, pulling the disc firmly over the defect.[5],[19]

1600 AD

In 1670, a Dutch surgeon, Van Meekren, allegedly performed cranioplasty using bone of canine origin, impelled the use of alternative alloplastic materials.[20]

Tycho Brahe (1546–1601), used a nasal prosthesis to rehabilitate his own nose that was lost in duel. His earlier nasal prosthesis was made up of wax, which turned out to be dissatisfying; he therefore enlisted the assist of a goldsmith to make a metallic nasal prosthesis to conceal deformity. A wax form was fabricated followed by casting. Exterior of the metallic nasal prosthesis were stained with oil paints to simulate patient's skin tinge. Prosthesis was fastened to the remaining nose with the aid of a sticky medium. There are disaccords as to either the nasal prosthesis was assembled in gold, silver, or copper. Most likely, an alloy of gold/silver and copper has been used to accomplish the optimal mechanical properties at conceivably lessen costs.[21],[22]

A milestone for the ocularist profession was delineated by Fabricius ab Aquapendente, an Italian surgeon in 1619, at this time prosthetic glass eyes were made in Venice.[13]

An exceptional work to the development of maxillofacial prostheses was done by Pierre Fauchard (1678–1781), French dentist, by designing and fabricating multitude innovative intraoral and extraoral prostheses for individuals with maxillofacial deformities. Perhaps he was initiatory specialist who valued that an oral prosthesis could be used to rehabilitate the outer contour of the face in the event of severe bone loss in maxillofacial region. The facial prostheses constructed by Fauchard were mainly assemble of silver or papier-mâché.[23],[24],[25]

1700 AD

Prosthetic rehabilitation of the maxillofacial deformities grows widespread in Europe. Entities like ivory, gold, silver, wood pulp, glass, and even wood were materials to which artisans got accustomed. Also, inevitably the exigency of the hapless individual often entailed the participation of the artisan, who in most cases had little/no medical understanding to mentor them.[13]

The argument on the optimal choice of extraoral maxillofacial materials for prosthetic application began. For example, in his book entitled Chirurgie, German surgeon Laurent Heister said that prosthetic glass eyes were superior than metal eyes due to the better tolerance of conjunctival tissues to the glass. He also gave the artisans and the patient advice on the correct hygienic management of the prosthetic eye.[26] France became center of the ocular profession since indwelling and extraneous prostheses were fabricated by the presumed “ocularier.”

Exemplar of extraoral maxillofacial rehabilitation, “nasal prostheses,” which probably date from this aeon, are assemble of silver and other of ivory.[13]

1800 AD

One of the most notable, eloquent examples of extraoral maxillofacial prosthetic rehabilitation is that of the “Gunner with the Silver Mask.” French artillery gunner, Monsieur Alphonse Louis, a native of St. Laurent, Pas de Calais, suffered shrapnel wounds from a grenade that detonated during the beleaguer of Antwerp in 1832. Although, he suffered almost cataclysmic wounds but were immediately taken and operated followed by medical and nursing care, then hence protected his life. His facial injuries comprised deficit of the complete lower jaw and soft tissues above it. Sequel to it, he had a mutilate look and was incompetent to chew/speak correctly. Once he recuperates adequately, Dr. Forget, a dentist, made his facial moulage. This was used to construct a prosthesis that rehabilitates shape and function. Based on this cast and the design concept, Mr. Verschuylen, an artesian, constructed a sliver sectional mask that contained jointed components that could be used to disassemble the device for cleaning. Facial mask support and retention was procured by means of attached leather straps that were placed around the patient's neck and back of the head. Inside the mask itself was a folding section that had golden teeth and underneath was a drainage chamber. Face mask outer surfaces were stained with oils to simulate the patient's skin tones with inclusion of a fake moustache and sideburns, which gave prosthesis an overall realistic appearance.[27],[28]

An alike situation was also reported of French soldier named Charles E Verney, who was wounded by a bullet in the Battle of Jena in 1806 which destroyed much of his lower jaw, upper jaw, destroys the dentoalveolar process and a large part of the soft tissues of the face above it, therefore rehabilitated with a silver face mask.[12]

Dr. Christophe Francois Delabarre defined in 1820 codified methods as the art and practice of maxillofacial prosthodontics today.[29] Prof. Adolf Bardeleben delineated in an interesting article about a patient he cared for and fabricated a wooden partial nose prosthesis.[30] Bruck proclaimed that Le Fouley was accountable for engineering a variety of facial prostheses to cover nasal defects, the sheets of which were modified, mimicking amended curve of the affected area, particularly the nose deformities.[31] Concomitantly, Sehange, a German, was accredited by Stavros with the manufacture of numerous prosthesis for sufferers with maxillofacial defects.[32]

William Morton, famous for his disclosure of the usage of sulfuric ether for anesthesia, also made notable addition in maxillofacial prosthetics. He was accredited with constructing a porcelain enameled nasal prosthesis that matched the patient's complexion.[33] Around the same time, Brusotti, constructed facial prostheses that were mainly metal sub frames with a porcelain coating; with the end result imparting a very good skin facsimile.[34]

French ocularists, Hazard-Mirault, Desjardin and Boissenau, were also very diligent in the engineering of extraoral maxillofacial prostheses employing enameled metal appliances and glass eye prostheses. Constructing glass facio-orbital prostheses was a strenuous process, since the prosthetic eye had to be puffed out and the veins and iris-pupil unit had to be made and then the surrounding lost anatomy like eyelids, imitated in such a way that it mimics the contralateral eye and orbit, and form closeness with the anatomy of the deformity. In particular, glass fragile nature is susceptible to breakage; hence, prostheses fabricated from the glass took a long time to come in trend. In Germany, these facio-orbital prostheses were frequently called ekto-prostheses.[23]

Roald Larby, chief maxillofacial technologist at dental school at the University of Oslo, reported probably the first case of facial prosthetic rehabilitation in Norway. Additionally, probably it may be the preliminary that “vulcanite rubber” was utilized for this purpose.[35]

In 1839, Macintosh, Goodyear, and Hancock found that on heating a mixture of natural rubber with sulfur, natural rubber converts into a useful, nonsticky, stable material that could be molded into a tangible form that was heat stable and chemical resistant, especially in the biological habitat. This chemical process of forming of cross-linking between the molecules is called vulcanization.[13] George Moe reported a case report on facial prosthetic rehabilitation using artificially manufactured high polymer, of Danial Folkesen Oddeskar, a mountain farmer who suffered a facial injury including his jaws and removal of the nose, lip and much of the upper jaw; and also, devastation of the orbit and tooth loss in the lower jaw, along with soft tissues deficit.[35]

Cellulose nitrate is surmised to be the first of the modern plastics to be discovered. In 1846, Christian Friedrich Schonbei discovered nitrocellulose by nitrating paper, and found out properties like increase paper toughness, better water resistant and can electrified readily. Later, Alexander Parkes commenced several experiments with nitrocellulose and assessed its plastic possibilities with notable anticipation. He predicted the commercial value of a strong cost-effective material that could be molded into shapes, but also realize that as long as the plasticity depended on the presence of volatile solvents like alcohol and ether, it would be transient because the end product would contract and distort on drying. Hence, Park experimented with higher boiling point solvents like nitrobenzene and procured a considerably upgraded material. Although he attempted to use camphor (2%–20%) as plasticizer, but couldn't acknowledge camphor full value in combination with nitrocellulose. He branded it as Parkesine.[36] At the same time, in the US, John Wesley Hyatt, who was attracted to the offer of a prize for a suitable replacement for ivory billiard balls, was involved in the same topic. He encountered the same difficulties as Parkes in the shrinkage caused by the use of volatile solvents and went to the other extreme with nitrocellulose and camphor without liquid solvents. He assumed that once camphor is liquefied on heating, it acts as good solvent for nitrocellulose. But he also realized that camphor melts at a temperature much above the safety limit for nitrocellulose, hence, the process was dangerous and eventually replaced by a process that used enough ethyl alcohol to dissolve the camphor and thus reduce vary greatly the temperature at which the materials must be worked. Later, Hyatt called this mixture of nitrocellulose with camphor as Celluloid, which led to advent of engineered plastics. Hyatt and his brother made great contributions to the mechanical side of the industry and determined the value of mechanical processing, heat and high pressure in the manufacture of nitrocellulose plastic. Later, Hyatt's work led to the creation of the Albany Dental Manufacturing Corporation, which eventually became the US Celluloid Corporation. Later, several prosthetists such as Coulioux, Grohnwalt, Junse, Michails, and Klinman have been reported to use this material in their practice, but often got catastrophic consequences. Smoking resulted in nasal prostheses turning brown and occasionally catching fire. Its modified version, “cellulose acetate,” was used with better results, particularly in France.[36],[37]

In the second half of this century, usage of celluloid for cranioplasty was seen, but again with unacceptable outcomes, particularly due to its carcinogenic nature.[37] Probably, Tetamore was the first to use prosthetic techniques that noticed the merits of eyeglass frames usage as a retention source for nose and facio-orbital prostheses and as an aid of obscuring the edges of certain facial prostheses. The prostheses also consisted of very light, nonirritating plastic material (possibly nitrated cellulose).[38]

At Boston, Upham, proclaimed to use “vulcanite rubber” for 30 years to make obturators, nasal and auricular prostheses, claiming it as a better extraoral maxillofacial material due to its workable, odorless, and not easily breakable nature. On the other hand, according to him, celluloid was less workable and easily breakable.[39] Kingsley likewise preferred vulcanite usages as extraoral maxillofacial material to rehabilitate patient with maxillofacial defect.[40] Claude Martin, used vulcanite for both intraoral and extraoral prostheses. He often united obturator with external prostheses to accomplish utmost rehabilitation of shape and function. He also described the technique for making a porcelain nasal prosthesis.[41]

Harris and Austin reported in 1898 that Pretevce fabricated an extraoral maxillofacial prosthesis to rehabilitate a nose of the patient via a new elastic material, most likely Vella rubber.[13],[42]

In 1890, Andrews fabricated many extraoral maxillofacial prostheses, which were basically metallic denture base, on top of it, a soft rubbery material (possibly Vella rubber) was fused. In the same way, porcelain was also utilized by other workers at that time, i.e., the porcelain was fused to the precious metallic base.[13] Stavros reported that Sauer made a positive platinum base over which he melted a porcelain outer layer, sculptured to mimic contra-lateral facial anatomy.[32]

But some professionals considered vulcanite to be firm and nontransparent, hence attempts were made to cultivate alternative materials for use on the face, leading to development of a typical mixture of gelatin and glycerin that was initially formulated by Frohlich.[43] Credit for the addition and clinical usage of a resin reinforced wax-based thermoplastic material goes to Tritterman. The introduction of resin prevented the comparably low melting wax from warping once exposed to body heat and native environment. He named this extraoral maxillofacial material as Tridermalith. He also used gelatin-type prostheses which were fabricated in the following manner: 100 g softened and firmly compressed of bleached gelatin was mixed with 100 cc of glycerin. The two materials were heated and stirred continuously till a homogeneous mix achieved. This homogenous mix was then streamed into suitable molds to fabricate prostheses.[13]

In second half of the life, Archduke Otto of Austria worn a leather nasal prosthesis while participating in public ceremonies.[44]

Ludwig Muller-Uri, a trained manufacturer of eyes for the doll industry, on encouragement by Wursburg's Prof. Adelmann, used his ability for the fabrication of prosthetic eyes.[45]

1900 AD

The propulsion of advanced and coordinated attempts to enhance prosthetic rehabilitation multiplied throughout Europe and also in the US. In 1905, Albrect fabricated a facial prosthesis from a pressed copper base plate. He used heat to coalesce the enamel (to simulate skin tones) to the metal substructure.[46] In 1905, Baird and Baker fabricated nasal prostheses while Ottofy in 1915 fabricated obturators, ocular and nasal prostheses, all composed of black vulcanite rubber. They processed pink vulcanized rubber on the base and colored it with artist paint. But, the stiffness of the vulcanized rubber was an obstacle when it was fitted to the facial skin.[47],[48],[49],[50]

Colombe reported that Boissonneau made an orbital facial prosthesis of the ecblepharon type, which consisted of a pressed metal plate that mimicked the missing soft tissue structures on its outer surfaces, i.e., the eyelids and the surrounding facial configuration. In this case the glass eye was inserted from behind and held mechanically. The facio-orbital prostheses were riveted to a set of metallic eyeglass frame.[51]

Heening enhanced the “gelatin and glycerin compound” by compounding dyes and carbonate to change the opacity. It was distinct as the first soft and somewhat fleshy like extraoral maxillofacial material that mimics the softness and pliability of human skin. The principal disadvantage was its abrupt degradation due to its intake of high-water content by the atmosphere.[13] Zinsser also used this gelatin-glycerin compound, and named it “elastin.”[52] Bercowitsch described the technique of fabricating and staining of gelatin-glycerin facial prostheses using water-soluble stains.[53] Even though it had short clinical life, numerous prosthetists in the Germanic countries, mainly until and during the First World War, still carry on with it. Despite shortcomings, even vulcanized rubber usages also continued. Different staining methods were used for it.[5] Kazanjian detailed usage of celluloid colors to stain vulcanized rubber based extraoral maxillofacial prostheses.[54]

Captain Derwent Wood, an esteemed artist, designed and engineered extraoral maxillofacial prostheses that were often attached to eyeglass frames. He devised a fabrication technique, which consisted of making a plaster facial moulage of the mangled face and the surrounding morphology, followed by pouring of stone cast and then clay modeling of the deficient anatomy on the same stone cast. After accomplished agreeably, a counter form was poured over the outer surfaces of the facsimile form of the face and the surrounding edges of the deficient site. Wood then caused a layer of pure copper to be electrolytically laid into the mold cavity after the clay was removed. Vulcanite rubbers were also used to fabricate some facial prostheses. Regardless of the materials used, the outer surface prostheses were colored with oil paints to mimic the patient's skin tones.[55],[56] Anna Coleman Ladd, also used the similar prosthetic technique as designed by Wood, but Ladd's prostheses were comparatively lightweight and more characterized.[57]

William Brooks, an optical technician fabricated his own pressed aluminum nose prosthesis. Acid etching was done on the outer surface of the aluminum nasal prosthesis to create pitting, and then stained with skin-toned enamels and the prosthesis was fired to give a permanent outer stained coating. Later, he fabricated similar prostheses for other patients with maxillofacial defects.[13]

Klocke tried to engineer a new rubber based maxillofacial material, akin to the substance used in the printing company. But he got disinterested in fully researching this material and reused the gelatin preparation. He developed the following composition: 100 portions of gelatin, 50 portions of glue and 200 portions of glycerin. After the process was brought into the required form, in order to remove the shiny surface, it was immersed in formalin. This had inhibiting effect on microbial growth on or within the prosthesis and also changes the surface energy properties hence making the final prostheses more suitable for adhesive like gum mastic.[58]

Alexander Oidtmann was instrumental in fabrication of numerous intraoral and extraoral prostheses for cases with acquired malformation. When a communicating orofacial defect occurred, a combination of intraoral and extraoral prostheses provided mechanical benefits.[13]

Esser, engineered a postnasal inlay technique that enabled nasal eminence to be accomplished by inserting a prosthetic substructure into a skin-lined compartment.[59] Schuiringa made significant contributions to the development of elementary fundamentals of the maxillofacial prosthodontics. Vulcanite rubber, Hekolite, Resovin, Neo-Hekolite, and earlier iterations of acrylic resin were among the products she and her colleagues employed.[60]

Bulbulian and Clarke have described techniques for using pre-vulcanized latex with water-soluble colors for extraoral maxillofacial prostheses.[61],[62]

In the 1920s, Axt stated making extraoral maxillofacial prostheses employing a gold model, followed by staining with celluloid, zap on color. He also employed the pressed aluminum method for the fabrication of facial prostheses, later stained in the similar way as quoted earlier.[63] Lapierre, used cellulose acetate to make maxillofacial prostheses, especially nasal, oculofacial and auricular prostheses.[64] Otto Muller-Uri made glass based facio-orbital prostheses and celluloid and vulcanite based facial prostheses for additional facial structures. Occasionally, he even sculpted a mahogany facial prosthesis. Belatedly he collaborated with Gurth, who then developed an improved version of celluloid that was comparatively better than other forms of celluloid.[23]

Older vulcanite was replaced with the addition of acrylic resin to the dentistry in 1937 in both intraoral and extraoral dentures. Although stiff, still attracted most clinician due to its translucency, colourability, and ease of processing.[5] Dereck Pym and Stanley Brazier recognized the potential of acrylic resin and did plenty to institute the elemental techniques for using these materials as rehabilitative materials. Brazier used resin polymer stains (pink, clear), dentin and enamel stain for self-staining, and oil paints mixed with acrylic resin monomer to tint the facial prosthesis from the outside.[65] Fonder described the use of oil-based, self-polymerizing acrylic resin to make a nasal prostheses.[66] Transparent photographic colors were used by Henry Bigelow to color an acrylic resin facial prostheses.[67] To overcome the stiffness problem of acrylic resin, Tylman instituted usage of an elastic vinyl copolymer acrylic resin for facial prostheses. He employed acrylic resin colors for self-staining and water colors for external coloring. The surface tint was further protected by a fine coat of transparent acrylic resin.[68] Brazier also employed polyvinyl chloride (PVC) as a maxillofacial material, used acrylic resin in cranioplasties, and in his last years developed an facio-orbital prostheses that included a “blinking” eye.[65]

One of the earliest pioneers works on Palamed maxillofacial material was done by Elisebeth Stoiber. Soon, Clifford Wellington, acquired the basics of dentistry and used his credentials in facial prostheses, especially in the first endeavor in the usages of PVC and vinylized acrylics.

Schmit, gained approach to an earlier prototype of PVC, called it “elastoplastic” and employed in maxillofacial prosthetic rehabilitation. According to him, when the prosthesis was first fitted, it was pliable and looked very natural, but later the material got worse and in about 6 months it faded and harden. He further stated that elastoplastic based prostheses discharged a material which led to localized undesirable tissue backlash, leading him to develop a modified PVC system, called Epidon, which turned out to be more biocompatible, but unfortunately also prone to be broken down and discolored.

Joe Drane, emphasized to establish maxillofacial prosthodontics and technology on an applicable empirical basis by executing academic workshops and commencing exploration into this long ago scientifically missing zone of maxillofacial rehabilitation. During his lifetime, his professional colleagues called him the father of maxillofacial prosthetics.

Hans Tolmeijer and his workmate Wim de Ruiter accomplished exceptional improvement to the progress of orofacial prostheses, especially with regard to techniques of fastening and retention. They mainly focused on the use of thermoset acrylic resin for the manufacture of maxillofacial prostheses.

Introduction of variety of elastomers led to substantial progress in the manufacturing maxillofacial prostheses. Silicone elastomers attained acclamation among clinicians. Many techniques and materials have been documented in the literature using silicone elastomers to fabricate maxillofacial prostheses.

In France, Beniot emphasized to establish scientific based maxillofacial prosthodontics. He and his colleagues took over treatment of numerous cases with extensive orofacial deformities and also helped advance usages of “new silicone rubbers” in maxillofacial prosthodontics. He was also involved in developing and improvising the usage of implants in lower jaw after traumatic injuries and surgery to maintain functionality and image.[13] Simultaneously, George Barnhart, also developed new silicone rubbers to use as materials for the facial prosthesis. Together with Antti Hulterstrom, Barnhart made an important input in advancing the staining techniques of facial prostheses and were involved in exploring color science and its usage in facial prosthetics. Hulterstrom also hold accountability for developing a method known as “the logical and reproducible color system” to put the coloring of facial prostheses on a further sustainable and scientifically researched foundation.[69],[70]

Application of dry earth pigments diluted in clear acrylic resin for internal staining of silicone prostheses was given by Tashma.[71] Ouellette mixed dry mineral earth pigments in a silicone base material diluted with xylene for the external spray coloring of silicone facial prostheses. Facial tint was further protected by spraying a thin layer of catalyst on the prosthesis and then allowing it to polymerize.[72]

Firtwell and Bartlett used dry mineral earth pigments and silicone base materials to create base colors from which basic tones and surface colors can be formulated. The custom formulation for primary color and surface tint for each patient was recorded for future reference.[73] Schaaf reported on the use of standard artists' oil paint tattooed on the surface of silicone facial prostheses to simulate freckles, blood vessels, and general shading.[74] Fine described the use of colored nylon as the main dye for both the inside and outside coloring of facial prostheses.[75],[76] It was claimed that the flocking of nylon was more stable in color and would give a prosthesis a more natural appearance than mineral pigments from dry earth. A multi-layer color matching technique has been introduced for both chair and laboratory processes.[5]

Different types of elastomers have also been used to make facial prostheses. Lontz employed altered polysiloxane elastomers.[77] Gonzalez explained usage of polyurethane elastomers.[78] Lewis and Castleberry stated the likely usage of siphenylenes for facial prostheses.[9] Turner registered usage of isophorone polyurethane.[79],[80]

Udagma and Drane initiated usage of Silastic Medical Adhesive Silicone Type-A for the manufacture of maxillofacial prostheses.[81] The thin edges of the prostheses tore easily, and to overcome this problem, Udagama reported that premade polyurethane films were used as liners for facial prostheses made using Medical Adhesive Type-A.[82]

1990 to present

Advances in polymer chemistry have renewed interest in the advancement of new materials for maxillofacial prostheses. Antonucci and Stansbury are studying new generations of acrylic resins. Gettleman explained usage of polyphosphazenes for facial prostheses. Silicone block copolymers were also evaluated.[5],[83],[84] Cosmesil was investigated and advanced by Ray Winter at the Wales University which still undergoing further modifications in order to achieve younger and more adaptable types.[13] Bellamy developed a silicone formulation whose usage can enhance some important properties of silicone elastomers.[85] But still it is under clinical trial. Some have also advocated use of hydrogel as an extraoral maxillofacial material.[86],[87]

 Conclusion



Researches have made significant advances in extraoral maxillofacial prosthodontics. The form of prosthesis that rehabilitates the facial tissue, principally the overlying skin, must meet strict caliber to simulate living moving tissue. Although numerous extraoral maxillofacial materials are currently available, but none is ideal for simulating and rehabilitating lost facial structures. Each material has their own advantages and disadvantages. In the next part of this article, the development of some early extraoral maxillofacial materials will be discussed in detail.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Chalian VA, Drane JB, Standish SM. Maxillofacial Prosthetics: Multidisciplinary Practice. Baltimore: The Williams & Wilkins Co.; 1971.
2Worthington P, Branemark PI. Advanced Osseointegration Surgery: Applications in the Maxillofacial Region. Chicago: Quintessence; 1992.
3Lemon JC, Kiat-amnuay S, Gettleman L, Martin JW, Chambers MS. Facial prosthetic rehabilitation: preprosthetic surgical techniques and biomaterials. Curr Opin Otolaryngol Head Neck Surg 2005;13:255-62.
4The glossary of prosthodontic terms. J Prosthet Dent 2005;94:1-92.
5Beumer J 3rd, Curtis TA, Marunick MT. Maxillofacial Rehabilitation: Prosthodontic and Surgical Considerations. St Louis. Tokyo: Ishiyaku EuroAmerica, Inc.; 1996.
6McKinstry RE. Fundamentals of Facial Prosthetics. Arlington: ABI Professional Publications; 1995.
7Gonzalez JB. Polyurethane elastomers for facial prostheses. J Prosthet Dent 1978;39:179-87.
8Andres CJ, Haug SP, Brown DT, Bernal G. Effects of environmental factors on maxillofacial elastomers: Part II Report of survey. J Prosthet Dent 1992;68:519-22.
9Lewis DH, Castleberry DJ. An assessment of recent advances in external maxillofacial materials. J Prosthet Dent 1980;43:426-32.
10Danz W Sr. Ancient and contemporary history of artificial eyes. Adv Ophthalmic Plast Reconstr Surg 1990;8:1-10.
11Martin O, Clodius L. The history of the artificial eye. Ann Plast Surg 1979;3:168-71.
12Roman F. The history of artificial eyes. Br J Ophthalmol 1994;78:222.
13Conroy BF. A brief sortie into the history of cranio-oculofacial prosthetics. Facial Plast Surg 1993;9:89-115.
14Conroy BF. The history of facial prostheses. Clin Plast Surg 1983;10:689-707.
15Popp H. Zur Geschichte der Prothesen. Med Welt 1939;13:961-4.
16Remensnyder JP, Bigelow ME, Goldwyn RM. Justinian II and Carmagnola: A Byzantine rhinoplasty? Plast Reconstr Surg 1979;63:19-25.
17Hoffman-Axthelm W. Historical development of maxillofacial surgery. Zahnarztl Mitt 1977;67:423-33.
18Lufkin AW. A History of Dentistry. Philadelphia: Lea & Febiger; 1939.
19Pare A. The Workes of that Famous Chirurgion Ambrose Parey. London: Th. Cotes and R. Young; 1634.
20Umbach W. Zu Behandlung des chronischen intraduralen Hamatoms. Langenbecks Arch Klin Chir 1957;287:666-9.
21Dreyer JL. Tycho Brahe: A Picture of Scientific Life and Work in the Sixteenth Century. New York: Macmillan; 1890.
22Lee DC. Tycho Brahe and his sixteenth century nasal prosthesis. Plast Reconstr Surg 1972;50:332-7.
23Sarll DW. Plus ça change. Br Dent J 1997;183:141-4.
24Fauchard P. Le Chirurgien Dentiste ou Traite des Dents. 2nd ed. Paris: Mariette; 1746.
25Spielman AI. The birth of the most important 18th century dental text: Pierre Fauchard's Le Chirurgien Dentiste. J Dent Res 2007;86:922-6.
26Heister L. Chirurgie. Nurmberg: Stein and Raspe; 1752.
27Kaufman MH, McTavish J, Mitchell R. The gunner with the silver mask: Observations on the management of severe maxillo-facial lesions over the last 160 years. J R Coll Surg Edinb 1997;42:367-75.
28Renk A, Proff P. The gunner with the silver mask. An ingenious design for facial reconstruction in the 19th century. Fortschr Med 1987;105:59-61.
29Delabarre CF. Traite de La Partie Mecanique de L'art du Chirurgien-Dentiste, Vol. 2: Ouvrage Orne de 42 Planches. Paris: Pauteur; 1820.
30Bardeleben A, Vidal AT, Bardeleben AV. Lebrbuch der Chirurgie und Operationslehre. Berlin: de Gruyter; 1874.
31Bruck W. Gesichtprosthesen in Scheff's handbuch der Zohneilk Holder. Leipzig: Wienu; 1910.
32Stauros IS. The history of facial prostheses. Stomatologia (Athenai) 1971;28:127-36.
33Woodward GS. The Man Who Conquered Pain: A Biography of William Thomas Green Morton. Boston: Beacon Press; 1962.
34Brusotti A. Uber einige Felle von ausseren Nasen Prosthesen. Z Stomatol 1928;26:119-20.
35Larby R. Personal communication; and from The Aust-Agder Archives Kirstiansand, Norway.
36Sproxton F. The rise of the plastics industry. J Soc Chem Ind 1938;57:607-16.
37Kunz Z: Neutrochirurgie. Praha: Statni Zdravotnicke Nakladatelstvi; 1968.
38Tetamore FD. Deformities of the Face and Orthopaedics. Brooklyn, NY: Adams Printing; 1894.
39Upham RH. Artificial noses and ears. Boston Med Surg J 1901;145:522-23.
40Kingsley NW. A Treatise on Oral Deformities as a Branch of Mechanical Surgery. Santa Monica, California: Goodyear Pub.; 1880.
41Martin C. De la Prosthese Immediate Appliquee a la Resection Des Maxillaires: Rhinoplastie sur Appareil Prosthetique Permanent: Restoration de la Face Leuves, Nes, Langue Voute et Voile du Parais.Paris: G. Masson; 1889.
42de Caxias FP, dos Santos DM, Bannwart LC, de Moraes Melo Neto CL, Goiato MC. Classification, History and future prospects of Maxillofacial Prosthesis. Int J Dent 2019; 2019: 1-7.
43Frohlich C. Celluloid Prosthesen Klinische Blatter. Augenheilkunde: Berlin; 1881.
44Taylor E. The Fossil Monarchies: Collapse of the Old Order. London: Progress of Plastic Surgery; 1963.
45Muller-Uri L. Das Kunstliche Auge. Harrassowitz V: Wiesbaden; 1910.
46Bruhn C, Gutowski F, Gysi A, Hauptmeyer F, Loewe S, Kukulies K, et al. Zahnarztliche Prothetik. Heidelberg, Germany: Springer; 1926.
47Baird WH. An artificial nose. Dent Cosmos 1905;47: 560-1.
48Baker L. An artificial nose and palate. Dent Cosmos 1905;47:561-2.
49Ottofy L. An artificial nose for a Chinaman. Dent Cosmos 1905;47:558-60.
50Ottofy L. Dental and facial prosthesis in the Philippines. Dent Cosmos 1915;57:361-83.
51Coulomb R. L'oeil Artificel these Pour le Doctrat en Medecine. Paris: J B Bailliere et fils Pub.; 1905.
52Muir W. The Happy Hospital. “Observations of an Orderly”. London: Simpkin, Marshal and Kent; 1918.
53Bercowitsch GG. Facial restoration. Dent Cosmos 1928;70:167-70.
54Kazanjian VH, Rowe AT, Young HA. Prosthesis of the mouth and face: A symposium. J Dent Res 1932;12:651-93.
55Johnson WW. The history of prosthetic dentistry. J Prosthet Dent 1959;9:841-6.
56Wood FD. Masks for facial wounds. Lancet 1917;189:949-51.
57Romm S, Zacher J. Anna Coleman Ladd: Maker of masks for the facially mutilated. Plast Reconstr Surg 1982;70:104-11.
58Passow K. Herstellung kunsticher gesichtsprosthesen. Med Klin 1916;21:566-8.
59Esser JF. Esser Inlay (Epithelial Inlay). Leiden: E J Brill Pub.; 1940.
60De Boer M. Gedenkschrift voor Mei. JG Schuiringa (1887-1975), Lector bij het tandheelkundig Onderwils (1926-57). Ned Tijdschr Tandheelkd. 1975;82:490-93.
61Bulbulian AH. Facial Prosthesis. Philadelphia: WB Saunders; 1945.
62Clarke CD. Moulage prosthesis. Am J Orthodont Oral Surg 1941;27:214-25.
63Axt EF. A case of surgical prosthesis. Dent Cosmos 1927;69:828-30.
64Lapierre V. Les prostheses faciales par lacetate de cellulose. Rev Plast 1933;3:519-25.
65Brasier S. Maxillo-facial Laboratory Technique and Facial Prostheses. UK: Henry Kimpton's Pub.; 1954.
66Fonder AC. Dental materials and skills in oral facial prosthesis. J Am Dent Assoc 1955;50:636-46.
67Bigelow HM. Facial restorations. J Am Dent Assoc 1943;30:509-12.
68Tylman SD. The use of acrylic resins in restorative dentistry. J Am Dent Assoc 1946;33:1243-50.
69Barnhart GW. A new material and technique in the art of somatoprosthesis. J Dent Res 1960;39:836-44.
70Hulterstrom A. The logical and reproduceable color system. In: Conroy B, editor. The proceedings of the Institute of Maxillo-Facial Technology and International Facial Prosthetic Workshop. Part II. London: Institute of Maxillo-Facial Technology;1976.
71Tashma J. Coloring somatoprostheses. J Prosthet Dent 1967;17:303-5.
72Ouellette JE. Spray coloring of silicone elastomer maxillofacial prostheses. J Prosthet Dent 1969;22:271-5.
73Firtell DN, Bartlett SO. Maxillofacial prostheses: Reproducible fabrication. J Prosthet Dent 1969;22:247-52.
74Schaaf NG. Color characterizing silicone rubber facial prostheses. J Prosthet Dent 1970;24:198-202.
75Fine L. Color and its application in maxillofacial prosthetics. J Prosthet Dent 1978;39:188-92.
76Fine L, Robinson JE, Barnhart GW, Karl L. New methods for coloring facial prostheses. J Prosthet Dent 1978;39:643-9.
77Lontz JF, Schweiger JW, Berger AW. Modifying stress-strain profiles of polysiloxane elastomers for improved maxillofacial conformity. J Dent Res 1974;53:890.
78Gonzalez JB, Chao EY, An KN. Physical and mechanical behavior of polyurethane elastomer formulations used for facial prostheses. J Prosthet Dent 1978;39:307-18.
79Turner GE, Fischer TE, Castleberry DJ, Lemons JE. Intrinsic color of isophorone polyurethane for maxillofacial prosthetics. Part I: Physical properties. J Prosthet Dent 1984;51:519-22.
80Turner GE, Fischer TE, Castleberry DJ, Lemons JE. Intrinsic color of isophorone polyurethane for maxillofacial prosthetics. Part II: Color stability. J Prosthet Dent 1984;51:673-5.
81Udagama A, Drane JB. Use of medical-grade methyl triacetoxy silane crosslinked silicone for facial prostheses. J Prosthet Dent 1982;48:86-8.
82Udagama A. Urethane-lined silicone facial prostheses. J Prosthet Dent 1987;58:351-4.
83Feng H, Lu X, Wang W, Kang NG, Mays JW. Block copolymers: Synthesis, self-assembly, and applications. Polymers (Basel) 2017;9:E494.
84Saam JC, Gordon DJ, Lindsey S. Block copolymers of polydimethylsiloxane and polystyrene. Macromolecules 1970;3:1-4.
85Bellamy K, Limbert G, Waters MG, Middleton J. An elastomeric material for facial prostheses: Synthesis, experimental and numerical testing aspects. Biomaterials 2003;24:5061-6.
86Drury JL, Mooney DJ. Hydrogels for tissue engineering: Scaffold design variables and applications. Biomaterials 2003;24:4337-51.
87Mann BK. Biologic gels in tissue engineering. Clin Plast Surg 2003;30:601-9.