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Lorsque le document est trop grand pour Atre reproduit en un seul clichA, 11 est fllm6 A partir de I'angie supArieur gauche, de gauche A droite, et de haut en bas, en prenant le nombre d'images nAcessaire. Les diagrammes suivants illustrent la mAthode. errata I to 9 pelure, ;on d n t 2 3 32X 1 2 3 4 5 6 l^ ^■ k jozpy f *), ^' Land System of Dental Practice. n W. wO Devoted to the Art of Restoring the Dental Organs to their Natural Appearance. -^»f f-- ' ■ a^ r •'^-r. COPYRIGHTED 1893, BY CHA8. H. LAND. .< ' '-■%.. .^' -•^. i^fw" ■ /v^'^ ■ ^ ■■:- r- c 'V n INTRODUCTION. a 1 I IE practical application of porcelain to operative and median, ical dentistry is not possible without its necessary adjunct, a thoroughly reliable gas furnace; and this must be so arranged that all operations are reduced to the minimum cost of the material con- sumed and labor expended, and with the least fatigue both to the operator and his patient. Twenty years experience in the working of continuous gum work, sectional block and crown work, and six years constant and daily experience in inserting of porcelain enamel coats, bridge work, fillings, etc., has demonstrated and brought out so many minor details that in order to comprehend them prop- erly, nothing but actual practice will suffice to furnish anything like a correct idea of the great value of proper facilities; and, while it will be the aim of the author to simplify the instructions, the fact still remains that no matter how simple the art, there are always some features that need actual work. A very slight oversight on the part of the most careful observer may cost hundreds of dollars, where a little actual contact would save it all. A close inspection of any art reveals truths that cannot be com- prehended at a distance; therefore, to all those who will become interested, a week spent in our laboratory will be of ih- sreatest value; however, as there are a large number in the profess! m wha find it very difficult to get away from home, we have decided to do all that is possible by giving a series of illustrations and simple directions, and hope by this means to establish enough facts to en- able them to make a beginning. Respectfully, C. H, LAND. ILLUSTRATED EPITOME LAND SYSTEM OP DENTAL PI^AOTICE. WHAT IT IS AND WHAT IT MEANS. The process of burnishing metal foil into the cavity of a decayed tooth to secure an impression, and then melting either gold, silver or any suitable metal, or porcelain, glass, rubber, etc., into the mould, to form a solid section or plug, and the cementing the prepared sec- tion into the cavity or amalgamating it into the cavity of a decayed tooth by means of a new covihination of plastic metal that is ahao- lately impervious to the action of thefluiils of the inotith. Also the forming of a metal jacket or overcoat of very thin metal that fits over a defective tooth, and completely envelopes it, and placing thereon a thin coat and a veneer of porcelain, and then placing it in the muffle of a furnace and melting the enamel so that it becomes united to the prepared jacket, which, when finished, forms an enameled cap. It is then filled with plastic cement and pressed over the defective tooth, and becomes thoroughly established, thus restoring the defective organ so that it is not only useful for masti- cation, but also j)re8ents the exact color and characteristic appear- ance of its fellow members. Also the building up of the roots by certain methods especially adapted to this class of work. A particular plan of first lining the cavity of the tooth with an adhesive amalgam previous to inserting fillings, crowns, etc. Certain forms of porcelain veneers and porce- lain artificial crowns, to bo attached to the roots of teeth. Certain forms of gas furnaces, constructed especially for the oonyenient wse of the dentist, that will enable him to perform operations with great facility. This, together with upwards of twelve other patented devices, all pertaining directly to the Art of Dentistry, are the inventions of Dii. C. II. Land, of Detroit, Michigan. The improvements contemplate methods of practice that aim especially to preserve, restore and to save the natural teeth, provides facilities by which dentistry may bo elevated from the barbaric methods of extraction, and made to assume a position in harmony with kindness and humanity. WHAT IT MEANS. That the long and tiresome operation of filling teeth with gold may be dispensed with, not only protecting the defective organs in a much superior manner, but also making them assume their original appearance in shape, size and color. It means that the setting of artificial crowns and fillings may be established with cements that are absolutely impervious to the fluids of the mouth, and that they will not only bo held in position with a wonderful tenacity, but, in addition, the plastic metal adheres so firmly— both to the walls of the cavity in the tooth, and to the porcelain or gold section, or porcelain crown— that it is utterly impossible for moisture to work between, and in case it did, the material is indestructible so far as the secretions of the mouth are concerned. UMLUABLE. In this new process, the union of the amalgam with the glass or porcelain exerts an adhesive force of over one hundred pounds to the square inch of surface covered. This enables the dentist to attach very thin veneers of porcelain to old amalgam fillings; also porcelain cavity stoppers may be made to fit the caviiy of a tooth, and then amalgamated in place and held with a wonderful degree of tenacity. Artificial crowns of porcelain may be amalgamated to the roots of teeth without the necessity of resorting to the use of pins, posts or screws, the adhesion of the amalgam being muoh stronger than the usual platinum pins. In connection with the amalgam no cements are used ; it is strictly a metallic union, there- fore absolutely impervious to the action of the fluids of the mouth. H ii -•^mmmiia It mciiiiH tliiit tlu! cxcuhhIvo uhc of the ordinary nilver or anial- giiiri filliiij^, which turn ho hlafi<, miiy ho rclugatud to tho thingii of tllO ])|l8t. It nii-ans that thu uho of th tlic poiinihle cliancu of wearing an artificial (Icnttiro froni liinulri'ils of poiindH totlio fochlo adhnion of tlio Halivii, wliicli iit bent U novur raoro than a ft-w oiincux, ho that n cough or a mioozo will many tinicH eject the cTitiru dcnturo from tho mouth. Want of proper knowh'(li;e of the metiioil of treating diHuaMPil toeth, and l.iek of Hkill to malM3V~ 18 Effect of Carbon on Porcelain During Fusion. During the process of combustion in furnaces, whether the fuel is anthracite, coiie or gas, carbon cither in the form of decom- posed hydrocarbon or smoke or carbonic oxide, may be present in varying proportions according to the amount of air passine; through the combustion chamber, and in one or both forms is extremely liable to penetrate to the interior of the muffle, here to combine with the oxygen contained in the porcelain to form co bubbles, thus the body and coloring matter becomes deoxydized, making the mass porous and unfit for the purposes designed. In coal or coke fires the injurious elements are in excess of the air supply during the first stages of combustion, when porcelain ware should not be passed into the muffle until the mass of fuel has so far advanced into the higher stages of combustion as to liberate all of the hydrogen and carbonic oxide; this will be indicated when the whole body is at a glowing heat. Then there is little left but highly heated pure carbon for the oxygen of the air to combine with, therefore the muffle is not likely to contain injurious gases. It will also be observed that the natural draught of the chimney will have a tendency to exhaust a certain percentage of air into the muffle, so that if a small amount of gas should in some way penetrate the interior the oxygen would convert it into a harmless product. From this it will be seen that it is important not to close the mouth of the muffle too tight, but rjither leave a perceptible space between the stopper and the sides of the muffle for the free passage of air. Careful attention to the facts here given where coal or coke is the fuel will always insure reliable results. Gas or the Vapor of Gasoline for Fuel. When we adopt the gaseous form of fuel, although we have the same chemical elements to deal with, the order of things in some respects is reversed. In coal or coke fires the air is exhausted into the furnace by the draught of the chimney ; on the contrary, gas furnaces require a force blast. This causes a pressure in every direction, hence the products of combustion are carried into the muffle in large quantities, especially through cracks, that are sure to come even where the best known fire clay is used, and unless I I 14 I I some practical means is devised to overcome this evil reliable work cannot be done in gas furnaces. By placing porcelain in the interior of a gas furnace, where it is brought in direct contact with the flame, the effects >f the carbon may be thoroughly demonstrated, showing each degree in the variation of color according to the amount of air mixed with the gas during the progress of combustion, If the gas is in excess the porcelain will take up enough carbon to appear almost black and will manifest a difference in proportion as the air is increased, until it becomes in excess of the gas supply when traces of the effects of carbon will disappear. Theoretically an excess of air forced into the combustion chamber will cause perfect combustion, so that a piece of porcelain may be fused in what has been nominated the open flame (in reality the inclosed chamber of a gas furnace) and be a comparatively good result. But such methods are crude, the porcelain being exposed to the action of other foreign bodies liable to be present in manufactured gas, also small particles of flrebrick, etc., are apt to be blown into the enamel by the strong blast to furnish the necessary air. I have thoroughly tested furnaces of this description and found them to be unsatisfactory. The systematic and comfortable handling of porcelain den- tures demands the muffle furnace, for it enables one to keep the denture constantly in view to readily move the piece back or for- ward, turn them about and to let them rest m front of the muffle to dry out the moisture and then to advance them gradually into the interior. At the Same time the muffle may be held at the enameling heat; this enables the dentist to pass the piece in and out of the mufl[le within a very short time. The heat being constant will guarantee uniform results. Other important features consist in the ready adjustment of new muffles when the old ones become destroyed. In providing furnaces for dental operations it has been my especial aim to make them suitable for any of the available fuels, such as coal gas, gasoline, or natural gas. Also to be reliable in case the fuel did contain injurious products. How well this has been done must be seen to be appreciated. ^ wi r wiiiii ' iiiiil lfti i f ilii i ii t i '-f-^'- u tH.; . -f i iiai < *a « iai i » iiiii i«ti»i'' IT) PKRUOR CABINET FOR CONTINUOUS GUM WORK and PORCELAIN RESTORATION OF THE Deri tell OroaiiB. PATENT APPUEDIFOR. lATlON Si i 10 Mthough upwards of 40 years have elap«ed Mnce Dr. John Allen first brought to the notice of the Dental Profession his most perfect metho. th.- .l-Mllt> ;.!.• Miprlini If.Un.U I ,.• I ft of . .| r |.|M.|u.f.l 111 MIIV of tlic-"n!,l UKiK.-snf .il lu'i o .,,1 , o.k,' «i u'iiN i" fa.' I'HIri tlKlll sen. l.i'fnu., thr o.l.M. hi-iiiu ii'iiiaiUal.ly l.iinlit .iiiM lI.-ii, c\ fiv st.,..e Ml ilu- vvuik IS iuo.n.i)iislH-.l Nviili miciriii« pii-fisiuii. IMPORTANT K) MI;>MM;K5 OI THI: l»k(H HS.SION. If \,,ii wi-li In l.c in tlu> advaiK-f ^Mianl -ciiiii- tin- mipvovc- iiK'iU-iK'c-i'ss.iiv to uKiiut.tiu Ilu' lii-,'lH--t p-isition in the art. To all tlv.si' wiv. will tiiNt i-st iMish otllci's m the various lar>rc- cities with tlif ni.mv pateimMi ,U'n iros liere offerol, an unusual opportunity is presiMitcl in x\ hicli to take the lead in any coiuniunity as all who are without smh a.l\anta^ ^j lupvov c- T.> all ii's with imily is all who 1. >lt, MIcb. 18 The Bi-Muflle Gas Furnace FOR CONTINUOUS CUM WORK. Patented February 24, 1891. flues tor the same current of air to pass out inches high, )ili inches wide, 8 inches long. Price of this size Bellows for foot power Blower for motor Air cushion for same This furnace is arranged in the same manner as the smaller size, except in the form of burner, there being a battery of four, as indi- cated by Nos. 1, 2, ;{, 4. In operating the rear burn- ers are so regulated to pro- duce less heat than those forward by turning on a small (luantity of gas in order to throw the maxi- mum heat to the front end of the mume. V'ig. C is the connecting tube for gas supply and the rear tube is for the air. Fig. 5 indicates stop cock to supply air that passes between the muffles. Figs. 8, *.), 10 are escape Size of muftle 2% .... $ 100 00 T 00 40 00 10 00 3 00 ^'^^'""S 12500 Motor I 285 00 10 THE BI-MUFFLE FURNACE, HEDIUH SIZE. Fijj. 1, stop cock to regulate current of iiir passing be- tween the muffles. Fig. 2, air cock for blow-pipe. Fig. 3» Gas cock for blow- pipe. Fig. 4, gas cock for furnace burner. Fig. 5, connections from bellows. It is with a great degree of pleasure and sHtisf action that I am enabled to an- nounce to the Den- tal Profession and to the chemist the [At right 8lde just beneath the base will be connectlcDg ^Jvent of what may for gas. See page 21.1 be justly nominated the Ideal Furnace for practical and scientific work. In from 6 to 15 minutes the Dentist is enabled to fuse high grade porcelain with but little exertion and secure a variety of valuable results that has not been heretofore available, such as the converting of any old plain tooth into any desired shape, size,, color, etc., and from block body and veneers make his own style of tooth crown, add any style of platinum pins or loops to suit the individual case; make porcelain bridges, sections of block work^ moulded sections for filling teeth, partial crowns, etc.; change plain teeth into gum teeth, make inlays of artificial gum enamel on the anterior surface of teeth. Blowpipe and Crucible work, repairing of broken gum teeth. By the use of Mineral Paint change the colors of plain teeth or gum, crowns, etc. The only Furnace that provides a practical means of 20 thoroughly overcoming the liability of gassing, .nai.itan.s the color ana tranvlucency of bodies, and enamels even better than coal or coke fires. By reference to the engraving a series of stop cocks will be seen both to the right and left and one at the rear. They are in- tended to supply any desired (luantity of gas and air, and to mhn.t pre-determined volume of gases and vapors, either in ccmh.nation with one another or separate, and in any desireil proportion, either into combustion chamber or into mufilc. Then when it is desir- able to effect the rapid oxidation of any substance, a current of oxygen may be passed into the muffle; or when it is important to prevent oxidation a current of reducing gases is injected into the muffle to produce any desired chemical effect on substances placed therein. To the chemist it presents facilities whereby he may call to action the effects of heat of any desired temperature covering the whole range of analytical work, conveniently submitting the sub- stance operated on to the action of various gases and vapors with a degree of precision not heretofore attainable. The operation being reduced to such a miniature scale, it be- comes very easy to operate it by foot or hand power, as the small- est motor will' give abundant air supply, and thus make it auto- matic at a trifling expense as compared with the same advantage heretofore possible to obtain. Either gas or vapor of gasoline will yield equally good results. Two gallons of gasoline will give four days' service. From S.OOO*" to 4,000'' of heat may be obtained in from six to ten minutes heating a muffle 4 inches long by H^ inches in diam- eter. PRICE - - " ' $35.00 21 DlReCTIONS. The engraving A represents a furnace provided with a double muffle. See fig. 8, and sectional view B illustrating air current C C C passing between the interior and exterior muffle. Refer- ring to the engraving A the stop cock fig. 2 regulates the amount of air which is conducted through the adjustable support fig. 7, and between the muffles as. shown in the engraving B. Fig. No. 1 in the engraving A is the place to connect rubber tubing from the bellows. Fig. 4 is for gas supply; 9 stop cock to regulate quan- tity of gas flowing into the furnace; 5 gas for blow-pipe connec- tions; 3 air supply for blow-pipe connections, The space between the muffles should be partially packed with asbestos fibre at the front end of the muffles, leaving the small hole just under fig. 8 as an escape flue for the injected air to escape, and when the furnace IS in operation the quantity of air escaping at this point will indi- cate the proportion required by placing a small piece of wood in front of the hole when the superheated oxygen in the air will rap- idly consume the wood. A small amount of air is all that is neces- sary to pass between the muffles. This not only consumes any foul gases, but passes the residue out at the small hole just below fig. 8, and keeps all injurious gases from the interior muflle. THE USE OF GASOLINE. A convenient way in which to use Riisolini' is to pass a current of air through thp gpncriitor. This jiiv.s a ricJi hydro carbon, and is If ss liable to gas the teeth than when coal gas is us.'d. When gasoline is used a current of air from the bellows must be passed through thn generator; this carries the vapor into the combustion cliamber, mixed with the proper (luantity of air. The generator should not be more than half tilled with gasoline; if filled too full the lluid will l)e forced up the pii)e and is liable to overflow and ignite outside the furnace. After passing a current of air throueli the generator for some time, a heavy residue will accumulate; this should be thrown out, as it will not vaporize. The engraving 15 indicates tlie manner of malting the connections for the use of gasoline; here the furnace is shown standing on its end, so that all the connections may be better understood. Seventy-four gasoline may be used with as perfect results as any other hydrocarbon; and with the ordinary foot bellows, as manufactured by the Buffalo Dental Manufacturing Co., I can bake a set of continuous gum-work in fifteen minutes, starting from a cold muflle. All kinds of crucible work and soldering with the blow-pipe can be done equally well as with city gas. One gallon of gasoline, costing 15 cents, will bake a set of teeth. There- fore, dentists living In localities where there is no gas can secure equal ad- vantages In the use of 74 gasoline. . F»rice of Generator, »12.00 23 TO REPAIR CRACK5 IN THE MUFFLE. Take pure nHbt-stos fibre in an old mullle, lieat it up Id about the same lieat as it would take to melt gold, say 2,200" P., tiien mix, lirmd to a pow- der in a mortar, and mix with two-thinla more of powdered fire clity, make into a paste l)y the addition of water, can-fuily work tliis paste into the cracks in the mullle and let it dry by a gradual heat. VALUABLE ADVICE. Do not imagine that a blacksmith's bellows will answer the purpose of an air supply for the furnace ; while it may have plenty of volume, it lacks the pressure. Nor will hydrostulic apparatus do; it may furnish the pres- sure, but lacks the volume. If tlie gns meter is more than thirty feet from the furnace, and the sup- ply of gas not enough to give a rich and full volume, it will l)e due to want of pressure at the works, or to the small size of the pipes at the point of delivery. When there is not enough gas the first step will be to have the pipes replaced with a three quarter-inch main from the meter close up to the furnace. IMPORTANT. The rul)ber tubing connecting with the bellows and the furnace should be as short as possible. The lonirer the pipe the greater friction there is to overcome, and strain on the bellows. Also the increased work of the oper- ator will l>e materially affected. Even one foot of extra pipe will make a decided difference, not only with the extra exertion of the operator, but the lack of a strong jet of air into the burner will retard combustion, thus inter- fering with the successful operating of the furnace. NECESSARY MATERIAL FOR PRACTICING THE ART. For preparing sections for filiings.Platinum Foil equal to No. 60,gold leaf, is the proper thickness, and for large cavities No. 50 or 55 is recommended. For making the telescopes for crown work use Nos. 28 to 32 Plate. All should be well annealed by heating with the blow-pipe to a white heat. Where the lower front teeth are to be crowned an alloy of Platinum and Iridium is used. This is much stiffer and can be rolled to No. 35 Plate. Where it \i desirable to take up less Foom between the roots of the teeth this is recommended. There are now five standard shades of bodies or enamels, put up in one ounce packages; and liy mixing tliese in various proportions a great variety of tints may be had. Also a great variety of prepared veneers, representing the anterior surface of each class and size ol teeth, are put up in packages of 100, assorted incisors or molars and bicuspids, or cuspids. 94 ft "MiW " Wiiieil Gas Blast fimce ni Bloi-Pipe. Fig is connections for rubber hose from the be ws. Fig. 1, stop .coclc to turn .m gas. Fig. 2, gas for blow-pipe. Fig. 4, air for blowpipe. The illustration accompanying this article represents one of the most T«pid heaters designed especially for porcelain crowns and fillings, Includ- ing small sections for porcelain bridges. The object sought in this improve- ment is to secure in the least possible space and with the least expenditure of time, the highest effect, and with no greater expenditure of power than ds required to answer for the successful operating of muffle work, crucible work and blow-pipe. The entire apparatus, including blow-pipe, bellows stand and furnace 4069 not occupy more than ten Inches of space and can be conveniently car rled in a small hand satchel. Contains platlna muffle 3 Inches long, Ik inches wide, 1 inch high. F»ric3 of this Karnace, - - $30.00 Price of Muffle froi-n - SlO OO to SSO.OO According to weight of platina. .jsair 25 Detroit Post-Graduate School of Dental Art At the iirgfint reciuest of a utimber of my professionnl friends, I have hoen Indiurt'd to establish a school and l»llrniary suitable to impart instruc- tions in tlie various nietliods, including ••«»' of wlilch I am the author and inventor, and also other improvements which are adopted by the progressive men of the jirofession. The facilities that liave been concentrated into tiiis Dental Office, In- flrmiiry and Scliool, are exceptionally complete. Tlie course of Instruction consists iu methods of making continuous, gum on platina base, continuous gum on platinized silver base, continuous gum on cast metal base and on rubber. PARTIAL DENTURES. Continuous gum sections on gold, on platinized silver and on rubber. PORCELAIN SECTIONS. Inlays of glass, inlays of porcelain, inlays of gold, inlays of alloys of other metals, all moulded iu a metal foil matrix and then amalgamated or cemented into the cavity of a tooth. Qold coated porcelain sections for amalgamating into the teeth. Gold coated crowns to be amalgamated to the roots of teeth by meana of adhesive amalgam. GAS FURNACES. Four different forms and several styles. Seven years constant and.'daily experience with gas furnac s have brought out all teehnicalities and mad» the fusing of porcelain by means of gas or gasoline, far more perfect thaa possible with coal or coke. The liability of gassing porcelain has beea completely overcome by improved apparatus. INSTRUCTIONS. Dentists may take instructions and will not be required to purchase a furnace or office right unless they wish to make use of those parts that ar* covered by patents. One Month'a Course of Instructions in all Branches • ^60 One Week's Course $20 A thorough investigation is invited, for which no charges will be made. Address all communications to C. H. L-KMD. an Woocl-warcl A.ve. DETROIT. MIOH. ■», *-.■ 5 ,,. GAS FHRNA GE FAIUaRES . ■.. ;)► :•.,■.;-, -A;,/,. F7m^,pward8 of fifteen years there has been a constant effort on the part of hundretls ..f members of the profession to produce a convenient and reliable k^'s f">nace, and the general result is marked by almost as many wrecks One of the princ.ple causes of such, is the error of expecting the large furnace to be used for all kinds of porcelain dentures from a small filling to a full set of teeth, and then want the machine operated with no more trouble than the handling of a blow-pipe. Experience will prove the necessity of having at least from two to three types of furnaces in the laboratory, each constructed for a special line of work, one for continuous gum work, one for crown and bridge work, rilhngs, etc To expect to use a continuous gum furnace every day for crowns and fillings and then once a month for full sets of teeth, would be like running a Pullman car to accommodate one passenger. Practically the loss of extra time and the wearing out of more expensive muffles, the use of a larger quantity of gas, etc., would be equivalent to purchasing an expensive plant annually. Another equally serious mistake is the use of very small furnaces contam- ing platinum muffle., they should be characterized more as a toy, paying from $25 to $30 for apparatus too small to be of any real value to the dentist. Therefore, before purchasing, thoroughly investigate all sides of the art, and see if. in the long run, that which may appear the most expensive at first will not be the cheapest in the end. Those that run automatically may be the most expensive in the first instance, but in the saving of time alone will soon return the cost of the most elaborate plant. *-'->'"ji'S: tj^ V v'i^.-x-;. ' \\^^ ■■■*^ I ■■**"*' *^ -^' ■ ■* World'8 C<>1*^^*^*"^ Exposition. ^ * * Weexpect to have oil these furnacee in operation in the Manufacturers and Liberal Arts Building, north end of the gallery, Alec to organize a clasB for inbtructione in Chicago about June let. Send in your name at once if you wish to take a course, Termsj $10 per week, AddresSj C. H. LAND, 271 Woodward Avenue, Detroit, nichlgan. ke in. >-p \