The Use of Gold in DentistryAN HISTORICAL OVERVIEW. PART I

J. A. DonaldsonBritish Dental Association Museum, London, U.K.

Gold was first used in dentistry over 2 500 years ago, and its dental ap-plications have increased steadily, especially during the past 100 years,to the point where they now absorb over 80 tons of gold per annum. Thecourse of these developments is outlined in this review, Part II of whichwill appear in the next issue of Gold Bulletin.

Where and when gold was first used in connectionwith the care of the teeth as opposed to their decora-tion are matters of doubt and disagreement. A plausi-ble hypothesis by Huinphreys (1) proposed thatman's change from a way of life entirely dependent onhunting to one dependent on food production fromcrops and herds, extended his life span by one or twodecades so that the loosening of incisor teeth as aresult of degeneration of surrounding tissues — afeature of advancing age — became a problem. Hum-phreys suggested that with the development of earlygold metallurgy the possibility arose of holding looseincisor teeth in place by gold wire which was twistedaround them and the farmer canines.

Early Use of Gold Wire

Several dental historians have referred to thediscovery by Junker (2), in 1914, in a burial shaft atGiza, of two molar teeth held together by a gold wire,along with articles that he believed to date from thelate 4th or the Sth Dynasty in the third milleniumB.C. (This item is now in the Pelizaeus Museum inHildesheim (3)). Some have based on this onediscovery a belief in the existence in ancient Egypt ofprosthetic dentistry; others, such as Filce Leek (4)who suggested that the find might be part of anamulet, have disagreed. A recent re-examination ofthe available evidence by Hoffmann-Axthelm (5) in-dicates that such examples of binding teeth with goldwire as have been found in skulls excavated fromEgyptian burial grounds were not the result oftreatment on living persons but rather the consequenteof steps taken in the course of preparing corpses forembalming. Other examples of teeth bound togetherby gold wire were found in a pre-Columbian tomb atEsmeraldas, Ecuador, and in Etruscan burials (1).

The Etruscans appear, on such evidence as exists atpresent, to have been the first, as early as the seventhcentry B.C., to insert a substitute tooth by replacing

the gold wire by gold bands in front of and behind theincisor teeth on each side of the gap, drilling a holethrough both bands and the new tooth, and insertinga gold wire as a rivet. Many examples of suchprostheses can be seen in museums in Italy andelsewhere. In some cases the `artificial' tooth is thelost tooth with its root cut off, in others it is a portionof a tooth from a calf or cow. In a few instances, anartificial tooth has been fashioned from gold.

Few examples of Roman dental prostheses forwhich gold was used have survived, owing to thewidespread Roman custom of cremating the dead.However, the fact that the Law of the Twelve Tables,written in Rome during the fifth century B.C.,speeifies at the close of a rule prohibiting the burial ofgold articles with corpses the exception that '... itshall not be unlawful to bury or burn it with the goldwith which the teeth may perchance be boundtogether' is widely taken as supporting the view thatprosthetic dentistry was practised at. the time (6). In-deed, the Romans inherited many arts and crafts,including those of dental prosthesis, from theirEtruscan neighbours who during the sixth centuryB.C. ruled Rome. Celsus, in his `De re medica',describes the use of gold wire to bind to adjacent firmteeth those teeth which had been damaged by a blowor other accident.

The Greeks also practised cremation and littleevidence of their use of gold for dental purposes hasbeen found. However, the few dental appliances ex-hibited in Greek museums are strikingly similar toEtruscan work.

The practice of providing support for incisor teeththat had become loose was known to the Arabs andwas described by Albucasis who lived in the latterhalf of the eleventh century A.D. His treatise onsurgery exists in several manuscript versions and con-tains references to diseases of the teeth and gums, aswell as a recommendation that when teeth have

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become loose after a blow or fall, so that the patientcannot bite his food with them, they should be boundwith gold or silver wire to make them firm. Albucasisstates that gold is to be preferred as being unalterable,while silver turns green in a few days. It was for thisreason that gold was used in the mouth by theEtruscans and the other peoples mentioned above: itschemical inertness enabled it to withstand the cor-rosive action of the oral fluids which would have beenso evident when other metals and alloys known at thetime were used.

Later Use of Gold Wire

Other early writers on dentistry have describedapplications of gold wire in the mouth. Ryff (7)illustrated its use to reduce and fix a fractured mandi-ble. Paré (8) recorded the attachment by gold or silverwire of an artificial tooth made of bone or ivory to ad-jacent natural teeth. Fauchard (9), in his importantwork which may justly be called the first scientificbook on dentistry, described how `loose teeth can betightened by turns of gold wire' and gave detailed in-structions for annealing the wire in the fire, throwingit into vinegar to restore its colour and for its carefulapplication to the teeth. Mouton (10) in the first bookdevoted to prosthetic dentistry, gave an account of hismethod of retaining small dentures carved from ivoryby spring clasps of round gold wire which encircledadjoining teeth.

Gold wire continued to be used for purposes suchas tempory splinting of teeth loosened accidentallyuntil well into the present century and it was appliedduring World War I for inter-dental wiring in thetreatment of jaw fractures. During the past 40 years,

Two Etruscan dental prostheses made by passing thinstrips of gold round teeth on each side of a space fromwhich a tooth or teeth had been lost and rivetting the stripso as to hold the substitute teeth in place. In one case, theabutment teeth are present, but the artificial tooth is lost,and in the other case, the two substitute teeth, portions ofan animal tooth, remainPhotograph by courtesy of the Merseyside County Museums,Liverpool

however, it has been increasingly replaced by stain-less steel wire.

Filling Teeth with Gold FoilThe first printed book on dentistry, entitled 'Artz-

ney Buchlein' ('The Little Pharmacopaeia'), waspublished by Michael Blum in Leipzig in 1530.Under this title or as 'Zene Artznei' ('DentalMedicine') it appeared in some fifteen editions issuedby various German publishers in the sixteenth cen-tury. It is largely a compilation from earliermanuscript works by several authors. Chapter 5 ofthe 1536 edition which is kept at the British DentalAssociation Library, after a description of 'corrosion'or decay of the teeth, advises on its treatment:

`Scrape and clean the hole and the area of decay with afine small chisel or a little knife or a file, or with anothersuitable instrument, and then to preserve the other partof the tooth, fill the cavity with gold leaves'.

This advice is attributed to Mesue, one of those fromwhose writings the book is compiled, but there isdoubt as to his identity and no existing work by a per-son of this name is known in which reference is madeto the use of gold- foil to restore decayed teeth.However, that the procedure described by Blum wasindeed widespread in the Renaissance period is con-firmed by Giovanni d'Arcoli (11), who wrote thatteeth could be filled with gold leaf after cleansing ofthe cavity with acid, and by Giovanni da Vigo (12)who referred to the use of gold foil for this purpose.

Nineteenth Century AdvancesMethods of restoring carious cavities in teeth by

means of gold foil did not progress appreciably,.however, from the period of these references until thenineteenth century. Then, first as a result of a betterknowledge of the structure of teeth and the process oftheir decay, and secondly as a consequence of the in-vention of mechanical means for cavity preparation,advance was rapid.

Robert Arthur, who practised in turn in severalAmerican towns, made many improvements to the artof filling teeth with gold. In the opening chapters ofhis 'Treatise on the Use of Adhesive Gold Foil' (13),he presented a critical account of the common

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Michael Blusn's 'Artzney Buchlein' is the first printed bonk on dentistry. Chapter 5 of the 1536 edi-tion, published 6 years after the original editiou, briefly describes the preparation of decayedteeth for the filling of cavities in thees with gold leaf. A translation of the relevant sentence, the se-cond in the paragraph shown here, is given in the text of this articleReproduced by courtesy of the British Dental Association Library, London

methods of the period. The foil was cut into stripswhich were used as such, or rolled into `ropes', orfolded into `tapes' and placed round the cir-cumference of the cavity. More strips, ropes or tapeswere added from the tentre and space was made forfurther additions by pushing a wedge-shaped instru-ment into the partially filled cavity to force the goldagainst the walls until a degree of compaction wasachieved that was considered satisfactory. Other den-tists cut the ropes or tapes into short lengths or smallpieces. One such piece was forced into a corner at thebottom of the cavity, and others were placed aroundit, one by one, to cover the bottom; the filling wasthen built up, layer by layer, from further pieces.

`Sponge' or `crystal' gold was another form of den-tal gold, then only recently introduced, which was ex-amined by Arthur in his critique before he went on todescribe the superiority of his own 'adhesive foil'.Material of the former type originated in England andwas dismissed by Arthur as useless. Another varietywas invented by A. J. Watts in the U.S.A. and isdescribed in a patent specification as made by dissolv-ing the mercury from a Huid amalgam of gold bymeans of nitric acid. This left the gold in a finelydivided, easily manipulated state that could be bond-ed into a solid mass by pressure. The aim of Watts'invention was to reduce the tedium of filling largecavities piece by piece or strip by strip with foil, byinserting gold in the new form in bigger portions andcompacting it rapidly. In practice, the technique wasdifficult and, as Arthur rightly pointed out, pressureapplied to a large piece of the sponge or crystal goldcompacted it only superficially, leaving soft, weakareas beneath its surface. However, the use of gold inthese or related forms was not then discontinued.Similar products made by a number of methods wereintroduced from time to time and continued to flndapplication almost to the middle of this century.

Arthur's principal contributions to the techniquewere based upon his exploitation of the cohesive pro-perties of clean, annealed gold foil. He passed eachportion of foil through a flame before inserting it inthe cavity and devised methodical routines for fillingcavities of different shapes with metal of consistentdensity by using plugging instruments with smallworking ends and so exerting high pressures to com-pact the gold and weld it into a solid mass. Arthurwas not the only dentist to exploit the cohesive pro-perties of annealed gold foil, others did so at about thesame time. According to Boyes (14), for example,James Hogue, an Edinburgh practitioner, was using itin 1850. Nevertheless, to Arthur belongs the credit ofdeveloping a well thought out practical method, ofdemonstrating this to a professional society in 1855and of publishing a book on the subject in 1857.

Pure gold of many descriptions — sponge, crystal,matt, cohesive and non-cohesive among others — in-serted in small portions and laboriously built up toplug the cavity continued to be used for the next hun-dred years. Bach operator chose the form best suitedto his skill or the type of cavity he had to fi11. Thepresidential address by C. Spence Bate at the 1883annual meeting of the British Dental Association, inPlymouth, entitled `A Review of the ScientificProgress of Dental Surgery from 1771 to 1883' (15),contains the passage:

`We must congratulate ourselves on the great improve-ment that has taken place in the power of retainingdiseased teeth and restoring to usefulness such as would,a few years ago, have been considered hopelessly irre-coverable. The extent of this process of repair can bestbe understood by saying that, independent of amalgamand cement stoppings, 20 000 ounces [620 kg] of finegold is annually used in filling teeth ...'

Unfortunately, there is no indication whether this

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lllustrated here are but some ofthe many forms of gold availablefor dental fillings at the turn ofthis century. The foil wasmanipulated witti the tweezersand kept to hand on the chamoisleather `gold pad'

was the amount used world-wide or whether it wasonly that used in Britain.

As a cheaper form of restoration than one entirelyof pure gold, for use in four-walled cavities (that is,those involving one surface of a tooth), someoperators placed a sheeet of tin foil between two sheetsof non-cohesive gold foil and rolled their ropes orcyclinders from the composite material.

Gold Foil Filling Instruments

While a limited number of forms of gold wasdeveloped for the filling of cavities, dentists indulged

their noted individualism by designing plugging in-struments until a vast armamentarium existedand some dental depots, at one time, stocked hun-dreds of patterns. The need was to apply a high com-pressive load per unit area to the foil and, naturally,methods were devised to increase this load by impactand to speed the process by mechanical means. In thelate 1850's, John Tomes, in England, introduced hissimple mallet, made for him by the dentalinstrument-maker Jean Evrard. To judge from thenumber surviving in museums and private collec-tions, it must have had considerably popularity. It

Mallets for compacting cohesivegold foil into a solid mass: leadfilled hand mallet, Goode'sspring maller, Kirby's leveraction mallet, Bonwill's inechan-ical mallet for attachnient to afoot engine, Kirby's pneumatictnallet, and Webb's improvedBonwill electromagnetic malletPhotograph by courtesy of the BritishDental Association Museum, London

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was followed by many other mechanical hand malletsin Britain, on the Continent and in the U.S.A. Mostused the principle of a weight pulled against a spring,sometimes through a system of levers, and then sud-denly released to strike a plugging instrument orpoint.

It is reputed that it was hearing a Morse telegraphsounder working that led W. G. A. Bonwill to designhis electromagnetic mallet which, in a form muchimproved by M. H. Webb and introduced in 1877,enjoyed large sales in many countries. A descriptionof Webb at work, written by his patient W. H.Trueman, another dentist, and cited by B. L. Thorpe(16) gives some idea of the endusance required of bothpatient and operator:

`Dr. Webb ... did in my mouth his last but one heavyjob, filling four upper incisors using four books, one halfounce of gold foil. I went to Lancaster, arriving on aMonday afternoon; he had done the preliminary work inPhiladelphia. He began the next morning and for twodays 1 was in the chair, my mouth dammed from8.30 a.m. to 5 p.m. I did not get out and Webb was at meall the time except fifteen minutes for lunch. I wenthungry, not even a sip.of water as we were both anxiousthat there should be no mishap. Another day he workedon me from three to five hours and finished about teno'clock Sunday morning, altogether six days to fi11 fourteeth.'

Not only did the introduction of the foot engine (or`foot drill') in 1871 stimulate the invention of formsof chuck called `handpieces' in which burs, drills,abrasive wheels, discs and points, and small revolvingtools of other kinds could be used at different anglesto prepare teeth for restoration, but it also stimulatedthe invention of engine-driven mallets for gold foilcompaction. Bonwill designed such a mallet whereina small cylinder of hardened steel set in the cir-cumference of a wheel, with its axis at right angles tothe plane of the wheel and protruding slightly beyondits edge, struck once in each revolution the end of along plugging instrument that passed through thehandle of the appliance. When its patents expired,this mallet was widely imitated and many othermallets were produced which used various means totranslate rotational energy into impact energy.Pneumatic mallets were also developed, usuallyoperated by a pedal that either compressed a rubberbulb or worked a small bellows or a small air pump.One German instrument used the pedal and flywheelof a dental foot engine to drive a small double-actingair pump. In all instances, the air was led by a smallbore tube to the mallet in which it generally forced aweighty piston along a cylinder to strike the end of aplugging instrument.

The disadvantages of gold foil fillings lie in theirconspicuous colour and, in live teeth, their capactiy to

conduct heat, although the effect of the Jatter can begreatly reduced by lining the cavity with dentalcement. Among their advantages are the inert natureof the material, the way in which it can be forcedagainst the cavity edge to make a good seal and thefact that fillings can easily be polished and burnishedto a very smooth surface finish. Some years ago, cor-respondents to a dental journal reported gold foil fill-ings which had remained sound for several decades.

In the U.S.A. there are still enough proponents ofthe art or skill of filling cavities in teeth withmechanically compacted pure gold foil to support theactivities of a Society of Gold Foil Operators.

The Search for an Alternative to Gold FoilThe arduous and time-consuming process of filling

a cavity with gold foil involves much stress for bothpatient and operator, especially if the filling extendsinto more than one surface of a tooth. During the lasttwo decades of the nineteenth century and the firstfew years of this century, a number of dentiststherefore sought to devise some alternative means ofusing gold to achieve the same result.

A method of inlaying gold into cavities appears tohave been the aim of several experimenters in theU.S.A. A procedure of this type was seen as havingthe advantages that the inlay might be made in theabsence of the patient, and possibly by a 'mechanic'rather than the dentist, to fit a model taken from animpression of the prepared cavity. The finished inlaycould be cemented into place at the patient's nextvisit. For some years, porcelain inlays had been madeby swaging a thin platinum foil directly into the cavi-ty or into a plaster model of the cavity, lifting out thisso-called platinum matrix and filling it with porcelainpowder which was then fused in a furnace. Attemptswere made to adapt this method by making a similarplatinum matrix, melting gold solder into it to fi11 itand cementing the resultant inlay into place.However, the method was suitable only for cavitiesinvolving one surface of a tooth and these were theeasiest to fi11 with gold foil.

Another intricate method that was proposed, used agold matrix swaged against the walls of the cavity andfilled with a material resembling sealing wax, the ex-posed surface of which was carved to the shape of themissing external surface of the tooth. From this, a dieand counter-die were made and used to reproduce thissurface shape in thin gold plate. This shape and thegold matrix were then soldered together to make ahollow inlay.

Lost Wax CastingOthers attempted to use lost wax methods with

varying degrees of indifferent success. B. F.Philbrook, dissatisfied with the way in which his

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W. H. Taggart's development of the lost wax process for eastinlprostheses and the machine that he designed for this purpose aseen as constituting the basis of modern practice. The widespreation of investment casting in dentistry and as a major manufatechnique for gold jewellery bear witness to Taggart's ingenuit

amalgam fillings crumbled, attempted to make soft,fusible metal inlays by a lost wax process. In 1896, hefitted several white metal inlays and one gold inlayand the following year he read a paper about hismethod to a local dental society (17). George B. Mar-tin demonstrated in 1897 gold dummy or artificialteeth, called `pantics', for use on fixed bridges; thesewere soldered to gold crowns on the abutment teeth.He carved his pontics out of wax to fit between theabutment teeth on a plaster model, attached a flatgold sprue and invested them in a two-part mouldmade of plaster and asbestos. This was so shaped thatwhen the sprue had been removed, the wax burnedout and the gold melted in a depression above theresultant void, pressing the mould to close it wouldpush the molten gold into the void. About 1900, J. G.Schottler used a method to restore the biting edges offront teeth by placing a platinum wire in the rootcanal, building the required shape on the tooth withwax, inserting a warmed pin into the surface of thewax to lift it out and placing it in a bulk of invest-ment. When the investment was set he carved adepression around the pin until the wax was reached,withdrew the pin and burned out the wax. Gold wasmelted in the depression and pushed into the voidwith a metal implement or a carbon rod. Also, JohnA. Lenz devised a method for lost wax casting a goldchewing surface onto a gold band made to fit around atooth and obtained a patent for it in 1906.

Taggart's `New and Accurate Method'

However, to a meeting of the New York Odon-tological Society on January 15, 1907, William H.Taggart of Chicago read a lecture entitled `A Newand Accurate Method of Casting Gold Inlays' inwhich he described a lost wax technique which cantruly be said to have revolutionized restorative andprosthetic dentistry (18). The process used no newprinciple and some aspects of it had been anticipatedby other dentists, but, by careful experiment over aperiod which he stated later was 15 years, Taggarthad overcome a variety of physical and technical pro-blems to attain great precision. He described and thendemonstrated this process in full that evening. It hasremained fundamentally unchanged since then,

although it has been improved in some respects asnew knowledge has been acquired. Contemporary ac-counts of the meeting describe the fascination of theaudience, the prolonged applause and the admirationvoiced by participants in the discussion for what hehad put before them (19).

The apparatus used by Taggart employed a nitrousoxide and gas blowpipe to melt gold very rapidly towhat he described as `the boiling state', at whichpoint a lever was pulled down, switching off theblowpipe and applying compressed nitrous oxide tothe molten metal to force it into the mould. In addi-tion to devising his casting machine, Taggart in-troduced a number of ingenious features of his owninvention. The wax with which the model of the inlaywas made in the prepared cavity in the tooth was ofselected composition and had been repeatedly filteredwhile molten to remove particles of foreign matter.The wax model was removed from the cavity with theaid of a wire inserted into it while it was warm. Thewire was then inserted into a dome-shaped boss in thetentre of a metal disc, and a metal cylinder of suitablesize was placed around it and filled with an invest-ment material mixed with water. This material wasdevised by Taggart after much experiment and con-tained a high proportion of graphite. When the in-vestment had set hard, the domed disc was removed,the wire warmed and pulled out of the wax and themetal cylinder carefully warmed until the wax wasmelted and absorbed into the investment. This left avoid the shape of the inlay with a sprueway leadingdown to it from a depression in which the gold couldconveniently be fused.

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The simple casting apparatus (top), developed by Solbrig,utilized steam pressure which was released when a moistasbestos pad, fitted into the lid, was lowered onto the hotmould to force the mollen gold into the cavity

The sintplified hand-held version (bottom), akin to pliersand relying on the same principle as the bench-top model,was developed for the production of small gold castingssuch as inlays

A pinch of powdered

borax should be addedto the gold when it Ismetted, bul not before ItIs melted.

The response of the dental profession was rapid. Asnews of Taggart's method and the account of it in thejournals spread, dentists from all over the U.S.A.ordered his casting machine. He was a skilfulmechanic and a painstaking experimenter satisfiedonly with the best results he could achieve but, unfor-tunately, he had neither facilities to manufacture hismachine in quantity nor the ability to organize them,even though he had patented both the machine andthe process. While he was endeavouring to makesuitable arrangements with a manufacturer, dentistsimpatient to produce gold castings for inlays, bridgesand dentures invented other forms of casting ap-paratus and used them. When at last he was ready tosell his machine, Taggart found that the market for ithad gone and, disappointed by the loss of the profitshe had hoped for, he entered into long and com-plicated litigation aimed at forcing dentists to pay himfor a licence to use the method. Powerful oppositionto him was organized among American dentists andthe credit that he rightly deserved for his greatachievement was largely denied him.

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A modern cast gold alloy bridgewith the working model of the pa-tient's teethPhotograph by courtesy of Professor J. Bates,Dental School and Hospital, Cardifi; and theMetals Society, London

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Other Lost Wax Casting Apparatus

Taggart's results immediately stimulated interest inlost wax casting of gold and new developmentsfollowed. Thus, a centrifugal casting machine was in-vented by A. Jameson and was on sale by 1910.Several machines were also produced which used atank of compressed air in place of Taggart's nitrousoxide to force the metal into the mould. Two airpressure machines were produced in Great Britain,the first of them, that of the Dental ManufacturingCompany, being patented in 1908. In a variant of thecompressed air method, introduced in the U.S.A. byL. E. Custer, the casting cylinder was enclosed in aglass dome and the gold was melted by means of anelectric arc. As soon as the gold was molten, com-pressed air was admitted to the dome. Othermachines depended for their action on the applicationof a partial vacuum to draw the air from the mouldand to assist the molten gold to flow into it as a resultof the pressure differential.

At about the same time that Taggart was engaged inthe experiments that led to his announcement in1907, a Dr. Solbrig, in Paris, was also studying theproduction of gold inlays by a lost wax method (20).Solbrig produced a machine in which a pad of moistasbestos in a metal cap could be brought down on tothe top edge of the hot casting cylinder as soon as thegold was molten, when the pressure of the resultingsteam forced the gold into the mould. Taggart used acool mould and Solbrig appears to have been the firstto cast into a hot mould. The latter author stated thatthe moment to fuse the gold and bring down thedamp asbestos pad was when the glow viewed downthe sprue hole was a bright red. Before the end of1907, Solbrig also introduced his casting pliers whichachieved enormous popularity for the rapid produc-tion of small inlays.

Improvements to Dental Casting

J. G. Lane (21), having observed that castings madeby Taggart's method were consistently too small, at-tributed this to contraction of the gold on cooling. Hedeveloped an investment material containing a highproportion of silica which, when heated to about750°C, expanded and compensated for the shrinkage.Although accuracy of casting was much improved byLane, the method was less successful than he claimed.The next improvement was made by C. S. van Hornwho reviewed progress to date and described (22) hismethod of warming the wax pattern to a temperatureat which its expansion was sufficient to compensatefor the subsequent contraction of the gold, immersingit in investment mixed at that temperature and main-taining the temperature constant until the investmentwas fully set.

Subsequent research by many workers has produc-ed better machines, waxes, investments and goldalloys which have led to the reliable methods of thepresent day and their precisely predictable results. Inthe late 1920's, cobalt-chromium alloys were first in-troduced for casting dentures by the lost wax methodand their proponents suggested that they would becheaper and that dentures made of them would havebetter physical properties, in particular greaterstrength, than those made of gold alloys. However,about 20 years passed before some of the difficultiesof casting cobalt-chromium alloys with consistent ac-curacy and of finishing the castings were solved. Bythat time, the expense of the method was such thatgold alloy castings could often be produced morecheaply. Although subsequent increases in the tost ofgold have made cobalt-chromium alloys more for-midable rivals for denture work amongst dental prac-titioners and patients, gold alloys are still thematerials of choice for inlays, crowns and bridges.

References1 H. Humphreys, 'Early Problems of Dental Prosthesis',.7. R.

Coll. Surg. Edinburgh, 1966, 11, 253-2592 H. Junker, 'Giza, Bericht über Grabungen aufdem Friedhof

des Alten Reiches', Wien/Leipzig, 19293 W. Hoffmann-Axthelm, 'Zur Geschichte des Zahnersatzes',

Quintessenz, 1969, 12, 131-1364 F. Filce Leek, 'Did a Dental Profession exist in Ancient

Egypt?', Dent. Delin., 1969, 20, (Spring), 18-215 W. Hoffmann-Axthelm, 'Is the Practice of Dentistry in An-

cient Egypt an Archaeological Fact?', Bull Hist. Dent., 1979,27, 71

6 V. Guerini, 'A History of Dentistry', Lea and Febiger,Philadelphia and New York, 1909 (Reproduced by Liberac,Amsterdam, 1967)

7 W. H. Ryff, `Die Grosse Chirurgei', Frankfurt, 15458 P. Fauchard, `Le Chirurgien Dentiste', Jean Mariette, Paris,

17289 A. Par, `Oeuvres Complètes', Paris, 1573

10 C. Mouton, `Essai d'Odontotechnie, ou Dissertation sur lesDents Artificielles', A. Boudet, Paris, 1746

11 G. d'Arcoli, `Practica seu Exposito', Padua, 148012 G. da Vigo, `Practica Copiosa in Arte Chirurgica', Rome,

151413 R. Arthur, `A Treatise on the Use of Adhesive Gold Foil',

Jones, White and McCurdy, Philadelphia, 185714 J. Boyes, `Edinburgh Dentists and Porcelain', Univ. Edin-

burgh J., 1971, (December), 123-12615 C. Spence Bate, 'A Review of the Scientific Progress of Den-

tal Surgery from 1771 to 1883', 7. Br. Dent. Assoc., 1883, 4,493-501 and 531-546

16 B. L. Thorpe, 'A Biographical Sketch of M. H. Webb', Dent.Rev., 1904, 18, 155-162

17 B. F. Philbrook, Trans. Iowa State Dent. Soc,, 34thAnnu. Meet., May 4 to 7, 1897, 227-280

18 W. H. Taggart, `A New and Accurate Method of CastingGold Inlays', Dent. Losmos, 1907, 49, 1117-1121

19 Proc. New York Odontol. Soc., Dent. Losmos, 1907,49,1162-1172

20 B. Platschick, 'Dr. Solbrig's Method of Gold Casting', AshQ. Circ., 1907, (Sept./Dec.), 338-352

21 J. G. Lane, `Cast Gold Inlays', Dent. Dig., 1909, 15,489-49922 C. S. van Horn, `Casting: A Review and a Commentary In-

cluding a Technique which Makes Possible a Casting of theSame Size as the Wax Pattern at Body Temperature', Dent.Losmos, 1910, 52, 873-881

The second part of this article will be published inthe October 1980 issue of Gold Bulletin.

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