Evolution of orthodontic appliances /certified fixed orthodontic courses by Indian dental academy

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The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.

Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078

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  • ‘’
    “MEN will never barter their souls or spill blood for it ; yet this time-tested stainless steel,with the single exception of intrinsic value offers more desirable characteristics to the fine-metal worker yhan do the precious metals themselves. The craftsman asks only that his material be chemically INERT , naturally beautiful, strong yet amenable to his artistrty ; it is the buyer who measures precious metals by price.”

Transcript

  • 1. EVOLUTION OFOF ORTHODONTICORTHODONTIC APPLIANCESAPPLIANCES INDIAN DENTAL ACADEMYINDIAN DENTAL ACADEMY Leader in continuing dental educationLeader in continuing dental education www.indiandentalacademy.comwww.indiandentalacademy.com www.indiandentalacademy.comwww.indiandentalacademy.com
  • 2. INTRODUCTIONINTRODUCTION  The word orthodontics is derivedThe word orthodontics is derived from two greek words , ORTHOSfrom two greek words , ORTHOS meaning RIGHT OR CORRECT;meaning RIGHT OR CORRECT; and ODONTOS meaning TOOTH.and ODONTOS meaning TOOTH. AND the term “ DENTOFACIALAND the term “ DENTOFACIAL ORTHOPAEDICS “ was suggestedORTHOPAEDICS “ was suggested …….. By NORMAN BENNET.…….. By NORMAN BENNET. ORTHODONTICS may beORTHODONTICS may be described as the study of growth anddescribed as the study of growth and development of the masticatorydevelopment of the masticatory apparatus and the prevention andapparatus and the prevention and treatment of abnormalaties of thistreatment of abnormalaties of this www.indiandentalacademy.comwww.indiandentalacademy.com
  • 3. Orthodontics has made tremendousOrthodontics has made tremendous strides as a specialised branch ofstrides as a specialised branch of Dentistry. In fact, it was the FIRSTDentistry. In fact, it was the FIRST Bonafide dental speciality with theBonafide dental speciality with the SECOND oldest qualifying BoardSECOND oldest qualifying Board in ALL of DENTISTRY and MEDICINE.in ALL of DENTISTRY and MEDICINE. ORTHODONTICS was thenORTHODONTICS was then considerded a part of the regularconsiderded a part of the regular prosthetic course, and accordedprosthetic course, and accorded SECONDARY CONSIDERATION.SECONDARY CONSIDERATION. This academic affliation still exists,This academic affliation still exists, in some areas of the world, andin some areas of the world, and indicates a primarily mechanicalindicates a primarily mechanicalwww.indiandentalacademy.comwww.indiandentalacademy.com
  • 4. orientation of orthodontic philosphyorientation of orthodontic philosphy and treatment procedures.and treatment procedures. Fortunately, the developmentFortunately, the development of orthodontics as a speciality hasof orthodontics as a speciality has been more successful. Orthodonticbeen more successful. Orthodontic therapy depends upon the reactiontherapy depends upon the reaction of the teeth, and more generally theof the teeth, and more generally the facial structures to a gentle butfacial structures to a gentle but persistent force. Orthodontic treatmentpersistent force. Orthodontic treatment is based on the principle that ifis based on the principle that if prolonged pressure is applied to aprolonged pressure is applied to a tooth, tooth movement will occur andtooth, tooth movement will occur and the bone around the tooth remodels.the bone around the tooth remodels.www.indiandentalacademy.comwww.indiandentalacademy.com
  • 5. The term EVOLUTION according to dictionary means –’’ any process of FORMATION OR GROWTH; DEVELOPMENT. And an ORTHODONTIC APPLIANCE can be defined as— appliance by means of which mild pressure may be applied to a tooth or a group of teeth in a predetermined direction. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 6. APPLIANCES may be classified as;APPLIANCES may be classified as; REMOVABLEREMOVABLE FIXEDFIXED MECHANICAL FUNCTIONALMECHANICAL FUNCTIONAL www.indiandentalacademy.comwww.indiandentalacademy.com
  • 7. ““MEN will never barter their souls or spillMEN will never barter their souls or spill blood for it ; yet this time-testedblood for it ; yet this time-tested stainless steel, with the single exceptionstainless steel, with the single exception of intrinsic value offers more desirableof intrinsic value offers more desirable characteristics to the fine-metal workercharacteristics to the fine-metal worker than do the precious metalsthan do the precious metals themselves. The craftsman asks onlythemselves. The craftsman asks only that his material be chemically INERT ,that his material be chemically INERT , NATURALLY BEAUTIFUL, STRONGNATURALLY BEAUTIFUL, STRONG yet amenable to his artistry ; it is theyet amenable to his artistry ; it is the buyer who measures precious metalsbuyer who measures precious metals by PRICE.”by PRICE.” www.indiandentalacademy.comwww.indiandentalacademy.com
  • 8. the startersthe starters  Like metallurgy, dentistry has aLike metallurgy, dentistry has a long history of artistic creativity .long history of artistic creativity . Over 4500 years ago when the metalOver 4500 years ago when the metal worker was sweating copper fromworker was sweating copper from malachitemalachite for weapons, makingweapons, making primitive tools from “bia n pet”primitive tools from “bia n pet” (meteoric iron), and separating(meteoric iron), and separating GOLD from crushed quartz stoneGOLD from crushed quartz stone literally using what became knownliterally using what became known as the GOLDEN FLEECE, theas the GOLDEN FLEECE, the “TOOTHER” was likely splinting the“TOOTHER” was likely splinting the teeth of the Egyptian court.teeth of the Egyptian court. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 9.  Time passed from the Bronze AgeTime passed from the Bronze Age to the Iron Age and the industrialto the Iron Age and the industrial Revolution until, in the latter halfRevolution until, in the latter half of the 19of the 19thth century , Henry Cliftoncentury , Henry Clifton Sorby (1863-1887) and EdwardSorby (1863-1887) and Edward Hartley Angle (1886-1930)Hartley Angle (1886-1930) professionally ascended toprofessionally ascended to become the pioneers of modernbecome the pioneers of modern Metallography and modernMetallography and modern orthodontics, respectively. Yet fromorthodontics, respectively. Yet from all these artistic developments ,all these artistic developments , the formalized scientific underthe formalized scientific under standing of both fields was limitedstanding of both fields was limited to about the last 100 years .to about the last 100 years . www.indiandentalacademy.comwww.indiandentalacademy.com
  • 10. THE BEGINNINGSTHE BEGINNINGS  Teeth were regarded by the ancients asTeeth were regarded by the ancients as very precious to the extent that “ . . .very precious to the extent that “ . . . Special penalties [ were exacted ] forSpecial penalties [ were exacted ] for knocking out the teeth of an individual,knocking out the teeth of an individual, either freeman or slave.” As early aseither freeman or slave.” As early as 400 B.C , Hippocrates referenced in his400 B.C , Hippocrates referenced in his writings the correction of toothwritings the correction of tooth irregularities . And while Greece was inirregularities . And while Greece was in its Golden Age , the Etruscans ( theits Golden Age , the Etruscans ( the precursors of the ROMANS) wereprecursors of the ROMANS) were burying their dead with appliances thatburying their dead with appliances that were used to maintain space andwere used to maintain space and prevent collapse of the dentition duringprevent collapse of the dentition during life. Then in a roman tomb in Egyptlife. Then in a roman tomb in Egyptwww.indiandentalacademy.comwww.indiandentalacademy.com
  • 11. Breccia finds a number of teeth boundBreccia finds a number of teeth bound with a GOLD WIRE , and at the time ofwith a GOLD WIRE , and at the time of CHRIST , Aurelius Cornelius CelsusCHRIST , Aurelius Cornelius Celsus first records the treatment of teeth byfirst records the treatment of teeth by FINGER PRESSURE. Thus , inherentFINGER PRESSURE. Thus , inherent malocclusions and the use of correctivemalocclusions and the use of corrective force are recognized, the virtue offorce are recognized, the virtue of maintaining space is appreciated, andmaintaining space is appreciated, and the first orthodontic material isthe first orthodontic material is documented –documented – a golda gold ligature wireligature wire…… IN All these early references , itIN All these early references , it was clearly evident that the interest inwas clearly evident that the interest in treating irregularities of the teeth wastreating irregularities of the teeth was purelypurely esthetic.esthetic. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 12. EARLY CONTRIBUTORSEARLY CONTRIBUTORS The FRENCH and ENGLISH dominatedThe FRENCH and ENGLISH dominated the earliest contributions to the field ofthe earliest contributions to the field of orthodontics , which as yet had not beenorthodontics , which as yet had not been formally named. Among theseformally named. Among these contributors is PIERRE FAUCHARDcontributors is PIERRE FAUCHARD (1723) who Invents the expansion arch(1723) who Invents the expansion arch and gives the first comprehensiveand gives the first comprehensive discussion of appliances . The reputeddiscussion of appliances . The reputed father of dentistry details the use offather of dentistry details the use of ligature wires and gold or silverligature wires and gold or silver mechanical devices . He corrects teethmechanical devices . He corrects teeth using finger pressure and silk threadusing finger pressure and silk thread and intuitively recognizes that theand intuitively recognizes that the source of a force does not matter insource of a force does not matter in mechanotherapy .mechanotherapy . www.indiandentalacademy.comwww.indiandentalacademy.com
  • 13.  In 1819 Delabarre introduces theIn 1819 Delabarre introduces the wire crib,and this marks the BIRTHwire crib,and this marks the BIRTH of CONTEMPORARY orthodontics.of CONTEMPORARY orthodontics. Later, Schange would show thatLater, Schange would show that the gold wire crib affordedthe gold wire crib afforded adequate anchorage and formed aadequate anchorage and formed a base for attachments.base for attachments. A century later,Lufkin would stateA century later,Lufkin would state that “...Schange made an invaluablethat “...Schange made an invaluable contribution” because it reallycontribution” because it really marked the beginning of ---marked the beginning of --- www.indiandentalacademy.comwww.indiandentalacademy.com
  • 14. EDGEWISE. In the second halfEDGEWISE. In the second half of 19of 19thth century(1865), Kingsleycentury(1865), Kingsley advocates plates as retainingadvocates plates as retaining devices. In the early part of 20devices. In the early part of 20thth century, Angle would tout thiscentury, Angle would tout this device as one of the best toothdevice as one of the best tooth maintainers. Fifteen years latermaintainers. Fifteen years later Kingsley would write his book,Kingsley would write his book, ““ORAL DEFORMITIES”, whichORAL DEFORMITIES”, which would become the mostwould become the most comprehensive text on thecomprehensive text on the subject in its day.subject in its day. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 15. In 1877, Johnston wouldIn 1877, Johnston would recommend placing Zinc in arecommend placing Zinc in a predrilled hole of a steel jackscrew,predrilled hole of a steel jackscrew, which was simultaneously inventedwhich was simultaneously invented by Dwinelle and Gaine (1849),by Dwinelle and Gaine (1849), to “… give it the same immunityto “… give it the same immunity from oxidation asfrom oxidation as gold orgold or platinumplatinum.”Modern books term this.”Modern books term this the concept of the ‘ SACRIFICIALthe concept of the ‘ SACRIFICIAL ANODE’.ANODE’. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 16. thethe enlightenmentenlightenment In 1908,Norman William KingsleyIn 1908,Norman William Kingsley already called Angle “…one of thealready called Angle “…one of the greatest empirics of his day”.greatest empirics of his day”. Angle identified and lauded manyAngle identified and lauded many people who sought the truth –people who sought the truth – Fauchard,Fox,Harris,Kingsley,Fauchard,Fox,Harris,Kingsley, Magill,Schange and Wescott; .HeMagill,Schange and Wescott; .He also criticized and wrote scathingalso criticized and wrote scathing letters to those he thought wereletters to those he thought were poisoning the newly formed practicepoisoning the newly formed practice of “ORTHODONTIA” as it wasof “ORTHODONTIA” as it was called in 1917 . He particularlycalled in 1917 . He particularly admired Kingsley who , like Farraradmired Kingsley who , like Farrar www.indiandentalacademy.comwww.indiandentalacademy.com
  • 17. (1926),was hailed by his(1926),was hailed by his contemporaries as “the fathercontemporaries as “the father of orthodontia.”Kingsley madeof orthodontia.”Kingsley made particularly substantive contributions toparticularly substantive contributions to our knowledge of occipital anchorage,our knowledge of occipital anchorage, which in that period would have beenwhich in that period would have been using elastic straps, forgedusing elastic straps, forged Stubbs’ steel,and a swaged silverStubbs’ steel,and a swaged silver plate.plate. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 18. On the other hand, a material was theOn the other hand, a material was the proximate cause of the rift betweenproximate cause of the rift between those who used heavy and bulkythose who used heavy and bulky NICKEL-SILVER appliances(theNICKEL-SILVER appliances(the german school) and Angle and hisgerman school) and Angle and his contemporaries. In 1906, Angle andcontemporaries. In 1906, Angle and most of his graduates resigned frommost of his graduates resigned from the society, in part because of theirthe society, in part because of their difference towards nickel- silverdifference towards nickel- silver alloys( ie, German silveralloys( ie, German silver or“NEUSILBER”), which were firstor“NEUSILBER”), which were first introduced by Angle to the U.S inintroduced by Angle to the U.S in 1887 but which were actually1887 but which were actually Copper, Nickel, and Zinc Alloys thatCopper, Nickel, and Zinc Alloys that contained no Silver.contained no Silver.www.indiandentalacademy.comwww.indiandentalacademy.com
  • 19. Composition of ALLOYS used during 20th century www.indiandentalacademy.comwww.indiandentalacademy.com
  • 20. During this period, Gold, Platinum, Silver, Steel, Gum rubber, Vulcanite and, occasionally, Wood,Ivory, Zinc and Copper were used as was brass in the form of loops, hooks, spurs and ligatures. 14-18 -karat Gold was routinely used for wire bands, clasps, ligatures, and spurs,as were iridium- platinum bands and archwires and Platinized gold for brackets. The advantage of gold was that you could heat treat it to variable stiffness(30%) , which was comparable to today’s beta-titanium alloy. This was accomplished by heating at 450°C(842°F) for 2 www.indiandentalacademy.comwww.indiandentalacademy.com
  • 21. REPORTED PROPORTIES of ALLOYS used during 20th century www.indiandentalacademy.comwww.indiandentalacademy.com
  • 22. minutes, cooling to 250minutes, cooling to 250°°C(482C(482°°F)F) over a period of 30 minutes, andover a period of 30 minutes, and finally quenching to roomfinally quenching to room temperature. Gold has excellenttemperature. Gold has excellent corrosion resistance too.corrosion resistance too. In 1920, Dewey presents a paper onIn 1920, Dewey presents a paper on clock spring auxiliary as anclock spring auxiliary as an “Application of spring forces from“Application of spring forces from Gold and Platinum removableGold and Platinum removable Appliances.” This presentation wasAppliances.” This presentation was credited as being the long awaitedcredited as being the long awaited response to the nickel-silverresponse to the nickel-silver appliances that caused the rift 14appliances that caused the rift 14 years earlier.years earlier.www.indiandentalacademy.comwww.indiandentalacademy.com
  • 23. known as the edgewise appliance whichknown as the edgewise appliance which was never formally named by EDWARDwas never formally named by EDWARD ANGLE in his lifetime.ANGLE in his lifetime. Finally, in the Dental cosmos(1928)Finally, in the Dental cosmos(1928) we see the design of what was to bewe see the design of what was to be www.indiandentalacademy.comwww.indiandentalacademy.com
  • 24. EDGEWISE PARAPHERNALIA OF 1928 WINGLESS BRACKET Without an archwire engaged With an archwire engaged www.indiandentalacademy.comwww.indiandentalacademy.com
  • 25. EDGEWISE PARAPHERNALIA OFEDGEWISE PARAPHERNALIA OF 1928 PROTOTYPE OF MODERN BRACKET Without an archwire engaged With an archwire engaged www.indiandentalacademy.comwww.indiandentalacademy.com
  • 26. Type of STAPLE THREADED WASHER used as spacer LIGATURE WIRE www.indiandentalacademy.comwww.indiandentalacademy.com
  • 27. On Aug 11,1930,EDWARD ANGLE passedOn Aug 11,1930,EDWARD ANGLE passed into history. As a tribute to him, we shouldinto history. As a tribute to him, we should recognize that in a 40 year career, herecognize that in a 40 year career, he truly did understand patients and theirtruly did understand patients and their tissues , had knowledge of Biology andtissues , had knowledge of Biology and engineering, comprehend mechanicalengineering, comprehend mechanical requirements, and contributed 4 distinctrequirements, and contributed 4 distinct Biomechanical Appliances–Biomechanical Appliances– the Angle E arch(1909),the Angle E arch(1909), the pin and the tube appliance(1911),the pin and the tube appliance(1911), the ribbon arch(1915), andthe ribbon arch(1915), and the edgewise appliance in the year 1925 .the edgewise appliance in the year 1925 . www.indiandentalacademy.comwww.indiandentalacademy.com
  • 28. No one has yet eclipsed thoseNo one has yet eclipsed those accomplishments. One couldaccomplishments. One could readily argue that Edward Anglereadily argue that Edward Angle was one of the first biomedicalwas one of the first biomedical engineers. Yet with all theseengineers. Yet with all these accomplishments, Angle wasaccomplishments, Angle was notnot thethe greatgreat innovator of novel materials–innovator of novel materials– others wouldothers would fulfill that role.fulfill that role. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 29. STAGNATION ABOUNDSSTAGNATION ABOUNDS From the 1930s to the1960s theFrom the 1930s to the1960s the proliferation of materials did not occur.proliferation of materials did not occur. With the death of Angle, a time ofWith the death of Angle, a time of stagnation eventuates .ASstagnation eventuates .AS THUROW said, “…the ‘edge-wise men’THUROW said, “…the ‘edge-wise men’ literally rode off in all directions at once”literally rode off in all directions at once” what became more important at that timewhat became more important at that time because of their lack of development werebecause of their lack of development were CEPHALOMETRICS AND BIOLOGICALCEPHALOMETRICS AND BIOLOGICAL ASPECTS. And so for a while, thoseASPECTS. And so for a while, those fields of knowledge were emphasized, asfields of knowledge were emphasized, as profound changes to orthodonticsprofound changes to orthodontics occurred at the expense of novel materialsoccurred at the expense of novel materials www.indiandentalacademy.comwww.indiandentalacademy.com
  • 30. andand innovative mechanics .It is duringinnovative mechanics .It is during this period that BEGG gives thisthis period that BEGG gives this warning to thewarning to the orthodonticorthodontic communitycommunity: “: “Orthodontics is ill-servedOrthodontics is ill-served by presentation of new orthodonticby presentation of new orthodontic techniques that are claimed to be basedtechniques that are claimed to be based on adaptations of engineering principleson adaptations of engineering principles but that have not been proven suitablebut that have not been proven suitable for successful treatment of patients.”for successful treatment of patients.” During this materials stagnation, weDuring this materials stagnation, we learn that gold alloyslearn that gold alloys have deficiencieshave deficiencies too. At the 1931 meeting of thetoo. At the 1931 meeting of the American Association of OrthodontistsAmerican Association of Orthodontists (AOO), Norris Taylor and George(AOO), Norris Taylor and George Paffenbarger discussedPaffenbarger discussedwww.indiandentalacademy.comwww.indiandentalacademy.com
  • 31. wrought alloys and intimated thatwrought alloys and intimated that more springiness and fewer cracksmore springiness and fewer cracks at tension points were possible. Andat tension points were possible. And at nominally $30 per ounce,Kelseyat nominally $30 per ounce,Kelsey said that they were costly. Little didsaid that they were costly. Little did they know that the cost of gold wouldthey know that the cost of gold would spike to $900 in early 1980.!spike to $900 in early 1980.! By the early 1930s, stainlessBy the early 1930s, stainless steels were generally available.steels were generally available. Although Dumas, Guillet, andAlthough Dumas, Guillet, and Portevin first made stainless steel inPortevin first made stainless steel in France, its “stainless” qualities wereFrance, its “stainless” qualities were first reported inGermany by Monartzfirst reported inGermany by Monartz www.indiandentalacademy.comwww.indiandentalacademy.com
  • 32. also around 1900-1910. Stainless steelalso around 1900-1910. Stainless steel languished until World War 1 spurredlanguished until World War 1 spurred the development of 3 different kinds ofthe development of 3 different kinds of stainless steels, and ironically thosestainless steels, and ironically those developers received the credit for thedevelopers received the credit for the discovery. During that war, thediscovery. During that war, the Germans, British, and AmericansGermans, British, and Americans developed an austenitic, a martensiticdeveloped an austenitic, a martensitic and a ferritic stainless steel,and a ferritic stainless steel, respectively.respectively. On the other world, in the early 1940’s,On the other world, in the early 1940’s, Begg would partner with Wilcox toBegg would partner with Wilcox to make what they envisioned to be themake what they envisioned to be the ultimate in resilient orthodontic wires–ultimate in resilient orthodontic wires– Australian stainless steels.Australian stainless steels. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 33. Yet it was not until about 1960 thatYet it was not until about 1960 that stainless steel was generally accepted.stainless steel was generally accepted. Nonetheless, in 1933 we find thatNonetheless, in 1933 we find that stainless steel and a chromium alloystainless steel and a chromium alloy are being used, as Archie Brusse (theare being used, as Archie Brusse (the founder of rocky mountain metalfounder of rocky mountain metal product) -- and so theproduct) -- and so the strugglestruggle betweenbetween gold and stainless steel formally begins.gold and stainless steel formally begins. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 34. PRODUCTS made from ALLOYS that orthodontics adoptedPRODUCTS made from ALLOYS that orthodontics adopted 1936 FORD SEDAN made from stainless steel www.indiandentalacademy.comwww.indiandentalacademy.com
  • 35. MAINSPRING of WATCH fabricated from COBALT CHROMIUM alloywww.indiandentalacademy.comwww.indiandentalacademy.com
  • 36. HYDRAULIC shape-MEMORY COUPLING manufactured from NICKEL-TITANIUM intermetallic composition www.indiandentalacademy.comwww.indiandentalacademy.com
  • 37. SR-71 BLACKBIRD constructed from TITANIUM-MOLYBDENUM alloywww.indiandentalacademy.comwww.indiandentalacademy.com
  • 38. Regarding Acrylics, unaestheticRegarding Acrylics, unaesthetic Vulcanite plates with 1.02mm(0.040-Vulcanite plates with 1.02mm(0.040- inch) resilient gold wires were replacedinch) resilient gold wires were replaced by translucent acrylic plates soon afterby translucent acrylic plates soon after acrylic’s discovery in 1937.acrylic’s discovery in 1937. Although Cellulose, PhenolAlthough Cellulose, Phenol formaldehyde vinyl polymers andformaldehyde vinyl polymers and copolymers, styrene, and alkyd resinscopolymers, styrene, and alkyd resins were explored, by the 1940s, acrylicwere explored, by the 1940s, acrylic materials were being poly-merized intomaterials were being poly-merized into plates by reacting, under heat andplates by reacting, under heat and pressure, doughs made from Methylpressure, doughs made from Methyl methacrylate monomer and acrylicmethacrylate monomer and acrylic powder the latter of which reducedpowder the latter of which reduced shrinkage.shrinkage. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 39. Ultimately, acrylic was so successfulUltimately, acrylic was so successful that in 1946, 98 % of all denture basesthat in 1946, 98 % of all denture bases were constructed of this polymer or ofwere constructed of this polymer or of its copolymers. Today acrylic is the mostits copolymers. Today acrylic is the most frequently used material for retainers –frequently used material for retainers – they be a Hawley or a lingual-wirethey be a Hawley or a lingual-wire retaining device.retaining device. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 40. What Kingsley(1908) said almost 100What Kingsley(1908) said almost 100 years ago still rings true today – that “…years ago still rings true today – that “… the success of orthodontia as a sciencethe success of orthodontia as a science and an art now lies in the retainer”.and an art now lies in the retainer”. But again stainless steel which isBut again stainless steel which is gaining prominence as the soft ligaturegaining prominence as the soft ligature wire, which was credited to Angle, is nowwire, which was credited to Angle, is now displaced by an 0.254mm(0.010-inch)displaced by an 0.254mm(0.010-inch) soft stainless steel wire. Only 3 yearssoft stainless steel wire. Only 3 years later ,Steiner introduces thelater ,Steiner introduces the 0.457mm0.457mm×0.711mm (0.018-inch ×0.028×0.711mm (0.018-inch ×0.028 inch) slot for stainless steel wires in lieuinch) slot for stainless steel wires in lieu of the 0.599mm ×0.711mm(0.022-inch×of the 0.599mm ×0.711mm(0.022-inch× www.indiandentalacademy.comwww.indiandentalacademy.com
  • 41. 0.028-inch) slot for gold alloys. And0.028-inch) slot for gold alloys. And even Jackson proposes to eliminateeven Jackson proposes to eliminate the Crozat appliance by fabricating itthe Crozat appliance by fabricating it in stainless steel and a nickel-in stainless steel and a nickel- chromium alloy (TOPHET metal) butchromium alloy (TOPHET metal) but still gold crozat appliance survives tostill gold crozat appliance survives to today.today. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 42. SOME PREMIER BRACKETSSOME PREMIER BRACKETS OF THE 20OF THE 20THTH CENTURYCENTURY The GOLD OR CHROMIUM alloy JOHNSON FRICTION CAPwww.indiandentalacademy.comwww.indiandentalacademy.com
  • 43. a SPEED self-ligating STAINLESS STEEL bracket www.indiandentalacademy.comwww.indiandentalacademy.com
  • 44. The STARFIRE single-crystal SAPPHIRE bracket www.indiandentalacademy.comwww.indiandentalacademy.com
  • 45. An ALLURE polycrystalline alumina bracket www.indiandentalacademy.comwww.indiandentalacademy.com
  • 46. To close out this age, a glimmer ofTo close out this age, a glimmer of things to come is seen asthings to come is seen as Buonocore proposes the use ofBuonocore proposes the use of 30- second,85% phosphoric acid30- second,85% phosphoric acid etch to enhance bonding ofetch to enhance bonding of acrylic materials to enamelacrylic materials to enamel surfaces.surfaces. It is now 1958, and DEWELIt is now 1958, and DEWEL unifies the practice and scienceunifies the practice and science under one aegis -----under one aegis ----- www.indiandentalacademy.comwww.indiandentalacademy.com
  • 47. ORTHOORTHO DONTICSDONTICS www.indiandentalacademy.comwww.indiandentalacademy.com
  • 48. PROLIFERATION ABOUDSPROLIFERATION ABOUDS By the 1960s, gold was universallyBy the 1960s, gold was universally abandoned in favor of stainless steel.abandoned in favor of stainless steel. This is how stainless steel wasThis is how stainless steel was marketed in lieu of goldmarketed in lieu of gold1) the force1) the force per unit activation of stainless steel wasper unit activation of stainless steel was greater than that of gold (ie, highgreater than that of gold (ie, high stiffness was an advantage)stiffness was an advantage) (2) by being smaller in size, stainless(2) by being smaller in size, stainless steel appliances were regarded assteel appliances were regarded as being more esthetic than goldbeing more esthetic than gold appliances (ie, the smaller theappliances (ie, the smaller the appliance is, the more it appears toappliance is, the more it appears to disappear). Stainless steel alsodisappear). Stainless steel also had excellent corrosion resistance,had excellent corrosion resistance, www.indiandentalacademy.comwww.indiandentalacademy.com
  • 49. work hardening capabilities, and awork hardening capabilities, and a frictional magnitude that was sofrictional magnitude that was so low that it became the standard oflow that it became the standard of the profession.the profession. A FULLY BANDED PATIENT WITH EXTENSIVE STAINLESS STEEL (SS) LOOP MECHANICS IN THE YEAR 1965 www.indiandentalacademy.comwww.indiandentalacademy.com
  • 50. In the 1960s, bracket bands areIn the 1960s, bracket bands are disappearing as the bondeddisappearing as the bonded miniature bracket appears – therebyminiature bracket appears – thereby punctuating the beginning ofpunctuating the beginning of esthetic orthodontics.esthetic orthodontics. Polycarbonate Brackets with Teflon coated Stainless Steel wirewww.indiandentalacademy.comwww.indiandentalacademy.com
  • 51. Again in the 1960s cobalt-chromiumAgain in the 1960s cobalt-chromium alloys are introduced. This alloys notalloys are introduced. This alloys not only contain cobalt, chromium, andonly contain cobalt, chromium, and molybdenum but also substantialmolybdenum but also substantial amounts of nickel and iron. This alloyamounts of nickel and iron. This alloy have high stiffness, and available inhave high stiffness, and available in 4 different tempers and are4 different tempers and are www.indiandentalacademy.comwww.indiandentalacademy.com
  • 52. heat treatable and thus it permitsheat treatable and thus it permits variable amounts of Formabilityvariable amounts of Formability which is required to place loops, V-which is required to place loops, V- bends and various offsets into thebends and various offsets into the archwire. Once deformation isarchwire. Once deformation is complete, however, heat treatmentcomplete, however, heat treatment increases the resilience of the wireincreases the resilience of the wire by a recommended precipitation- orby a recommended precipitation- or age-hardening process atage-hardening process at 482482°C(900°F) for 7-12 minutes.°C(900°F) for 7-12 minutes. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 53. In 1962 Buehler discoversIn 1962 Buehler discovers nitinolnitinol at theat the Naval Ordinance Laboratory, so-calledNaval Ordinance Laboratory, so-called because it was acronym for Nickel-because it was acronym for Nickel- Titanium Naval Ordinance Laboratory.Titanium Naval Ordinance Laboratory. Nitinol has the lowest modulus for anyNitinol has the lowest modulus for any cross section and has the most extensivecross section and has the most extensive deactivation (range) capabilities. Nowdeactivation (range) capabilities. Now light forces can be offered over alight forces can be offered over a protracted range as any of fourprotracted range as any of four combinations of passive or activecombinations of passive or active behaviour and of martensitic orbehaviour and of martensitic or austenitic phase are possible. In someaustenitic phase are possible. In some cases the thermoelastic or thecases the thermoelastic or the pseudoplastic effects(or) both are alsopseudoplastic effects(or) both are also exploited, the latter of which is alsoexploited, the latter of which is also termedtermed Superelastic, inSuperelastic, in part because thepart because the www.indiandentalacademy.comwww.indiandentalacademy.com
  • 54. material has so much springback aftermaterial has so much springback after displaying what appears to be puredisplaying what appears to be pure plasticity.plasticity. By 1970 Andreason brings theBy 1970 Andreason brings the intermetallic composition of 50% nickelintermetallic composition of 50% nickel and 50% titanium to orthodontics throughand 50% titanium to orthodontics through the university of Iowa.the university of Iowa. By 1986, two “superelastic” alloys areBy 1986, two “superelastic” alloys are offered– a japanese NiTi and a chineseoffered– a japanese NiTi and a chinese NiTi. These are active austenitic alloysNiTi. These are active austenitic alloys that form stress-induced martensite.that form stress-induced martensite. Most recently, nickel-free, titanium-Most recently, nickel-free, titanium- niobium wires have been introduced asniobium wires have been introduced as a finishing wire.a finishing wire. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 55. Returning to other materials of theReturning to other materials of the 1970s elastics of all sorts find their1970s elastics of all sorts find their niches in the orthodontic profession.niches in the orthodontic profession. Gum elastics were first employed byGum elastics were first employed by Maynard(1843); Tucker (1850) was theMaynard(1843); Tucker (1850) was the first to cut rubber bands from rubberfirst to cut rubber bands from rubber tubing. Plastic coatings on archwiretubing. Plastic coatings on archwire occur too. One such coating,occur too. One such coating, poly(tetrafluoroethylene) or teflon haspoly(tetrafluoroethylene) or teflon has the lowest friction. When this quite softthe lowest friction. When this quite soft material is placed in the hostilematerial is placed in the hostile mechanicochemicalmechanicochemical www.indiandentalacademy.comwww.indiandentalacademy.com
  • 56. environment of the oral cavity, theenvironment of the oral cavity, the coating skins off or disappears in ascoating skins off or disappears in as little as 3 weeks.little as 3 weeks. Self-ligating or ligatureless bracketsSelf-ligating or ligatureless brackets reappeared in the mid 1970s asreappeared in the mid 1970s as strite,Ltd, marketed them; thesestrite,Ltd, marketed them; these brackets had a stainless steel body andbrackets had a stainless steel body and a positive-locking ,spring-clipa positive-locking ,spring-clip mechanism. Their advantage was thatmechanism. Their advantage was that unlike conventional ligation, friction isunlike conventional ligation, friction is purportedly reduced– but mostpurportedly reduced– but most importantly, friction becomes moreimportantly, friction becomes more reproducible.reproducible. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 57. In 1977 the beta phase of titanium was stabilized at room temperature, and the aerospace titanium- molybdenum alloy (β-ΙΙΙ) was produced. This beta-titanium alloy has a modulus closet to that of traditional gold along with good springback, formability , and weldability. By the end of 1970s, four major groups of wire materials came into existence, 3 of developed different amounts of range for a given constant force or if you kept the same range www.indiandentalacademy.comwww.indiandentalacademy.com
  • 58. for a given constant deactivation. Asfor a given constant deactivation. As a consequence, the armamentariuma consequence, the armamentarium has expanded from just gold orhas expanded from just gold or stainless steel and two slots havestainless steel and two slots have been popularized – the 0.559mmbeen popularized – the 0.559mm (0.022-inch) slot , which was(0.022-inch) slot , which was originally used for gold, and theoriginally used for gold, and the 0.457mm (0.018-inch)slot, which was0.457mm (0.018-inch)slot, which was advocated for stainless steel. Withinadvocated for stainless steel. Within the capabilities of the presentthe capabilities of the present armamentarium, both slotsarmamentarium, both slots become viable alternatives.become viable alternatives. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 59. CONSOLIDATION OCCURSCONSOLIDATION OCCURS In the 1980s we haveIn the 1980s we have estheticesthetic bracketsbrackets made from single-crystalmade from single-crystal sapphire and from polycrystal-linesapphire and from polycrystal-line alumina– both having the same inertalumina– both having the same inert chemical composition, Alchemical composition, Al22OO3.3. We also have brackets made from poly-We also have brackets made from poly- crystalline zirconia material,ZrOcrystalline zirconia material,ZrO22 , which, which reportedly has the greatest toughnessreportedly has the greatest toughness among all ceramics. Unfortunately, bothamong all ceramics. Unfortunately, both these materials inhibit slidingthese materials inhibit sliding mechanics and they have debondingmechanics and they have debonding problems. The single-crystal bracketsproblems. The single-crystal brackets also exhibit specularalso exhibit specular www.indiandentalacademy.comwww.indiandentalacademy.com
  • 60. highlights, where as somehighlights, where as some polycrystalline ZrOpolycrystalline ZrO22 have intrinsicallyhave intrinsically odd colours. In the early 1990s theodd colours. In the early 1990s the first pseudocomposite wire fromfirst pseudocomposite wire from optical fibers is marketed, which finan-optical fibers is marketed, which finan- cially is a failure.cially is a failure. from these examples, we canfrom these examples, we can see that this was clearly a period ofsee that this was clearly a period of consolidation, as practitioners wereconsolidation, as practitioners were balking from products that just did notbalking from products that just did not work very well (as was the case inwork very well (as was the case in the1970s for the early Nitinol wires).the1970s for the early Nitinol wires). www.indiandentalacademy.comwww.indiandentalacademy.com
  • 61. and manufactures were beingand manufactures were being compelled either to improve them orcompelled either to improve them or remove them from their inventories.remove them from their inventories. Such was the case for early single-Such was the case for early single- crystal sapphire brackets becausecrystal sapphire brackets because during torquing, the tie-wingsduring torquing, the tie-wings tended to break off or, worse yet,tended to break off or, worse yet, removed facial enamel from the teeth.removed facial enamel from the teeth. Moreover, when placed on mandibularMoreover, when placed on mandibular incisors or canines, for ex; ceramicincisors or canines, for ex; ceramic brackets abraded or chipped thebrackets abraded or chipped the opposing maxillary teeth.opposing maxillary teeth. As if this was not enough, ceramicAs if this was not enough, ceramic brackets in combination with anybrackets in combination with any archwire, except nickel-titanium, alwaysarchwire, except nickel-titanium, always produced the highest frictional forces,produced the highest frictional forces, whether in the drywhether in the drywww.indiandentalacademy.comwww.indiandentalacademy.com
  • 62. or in the wet state. Furthermore,or in the wet state. Furthermore, optical fibers, whether coated withoptical fibers, whether coated with nylon or hot-melt adhesives, had suchnylon or hot-melt adhesives, had such low stiffness properties that theylow stiffness properties that they qualified as a “placebo” wire thatqualified as a “placebo” wire that would only acclimate a patient to thewould only acclimate a patient to the general architecture of his or hergeneral architecture of his or her appliances. Such a poor performerappliances. Such a poor performer would later handicap fiber-reinforcedwould later handicap fiber-reinforced composites in the corporate mind ofcomposites in the corporate mind of orthodontic manufacturers.orthodontic manufacturers. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 63. EXTRA-ORAL APPLIANCESEXTRA-ORAL APPLIANCES Extra oral forces in the form ofExtra oral forces in the form of hedagears and chincups, very similarhedagears and chincups, very similar of those of today was used byof those of today was used by orthodontists of the late 1800s. Bothorthodontists of the late 1800s. Both Kingsley and Angle described and usedKingsley and Angle described and used astonishingly modern appearingastonishingly modern appearing appliances of this sort with reasonableappliances of this sort with reasonable success. As orthodontic progressedsuccess. As orthodontic progressed in the early 20in the early 20thth century, extra oralcentury, extra oral appliances and mixed dentitionappliances and mixed dentition treatment were abandoned becausetreatment were abandoned because they were considered an unnecessarythey were considered an unnecessarywww.indiandentalacademy.comwww.indiandentalacademy.com
  • 64. complication.complication. A paper in 1936 by OPPENHEIMA paper in 1936 by OPPENHEIM revived the idea that headgear wouldrevived the idea that headgear would serve as a valuable adjunct toserve as a valuable adjunct to treatment.treatment. Rapid development in headgearRapid development in headgear treatment followed in 1950s and 1960s.treatment followed in 1950s and 1960s. with the demonstration in the 1960s ofwith the demonstration in the 1960s of skeletal changes from headgear forceskeletal changes from headgear force to the maxilla, interest in chin cupsto the maxilla, interest in chin cups revive.revive. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 65. Until the 1970s, face mask to bring theUntil the 1970s, face mask to bring the maxilla forward were dismissed asmaxilla forward were dismissed as ineffectual . The French surgeonineffectual . The French surgeon DELAIRE, working on cleft palateDELAIRE, working on cleft palate children, demonstrated that the maxillachildren, demonstrated that the maxilla can be moved forward if the protractingcan be moved forward if the protracting forces on the maxilla are used at earlyforces on the maxilla are used at early ages.ages. Facemask therapy is an area ofFacemask therapy is an area of continuing innovations in treatment incontinuing innovations in treatment in present and it may yet offer a morepresent and it may yet offer a more satisfactory way of treating maxillarysatisfactory way of treating maxillary deficiency problems than in the PAST.deficiency problems than in the PAST. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 66. FUNCTIONAL APPLIANCESFUNCTIONAL APPLIANCES The MONOBLOC developed byThe MONOBLOC developed by ROBIN in the early 1900s is generallyROBIN in the early 1900s is generally considered as the forerunner of allconsidered as the forerunner of all functional appliances, but thefunctional appliances, but the ACTIVATOR developed in norway inACTIVATOR developed in norway in 1920 by VIGGO ANDERSON was the1920 by VIGGO ANDERSON was the first functional appliance to be widelyfirst functional appliance to be widely accepted. Andersons activator becameaccepted. Andersons activator became the basis of “norwegian system” ofthe basis of “norwegian system” of treatment .Both the appliances systemtreatment .Both the appliances system and its theoritic underpinnings wereand its theoritic underpinnings were improved and extended elsewhere inimproved and extended elsewhere inwww.indiandentalacademy.comwww.indiandentalacademy.com
  • 67. Europe, particularly by the GermanEurope, particularly by the German school led by HAUPL.school led by HAUPL. HERBST APLIANCEHERBST APLIANCE This appliance was first developedThis appliance was first developed in the 1920s and re-introducedin the 1920s and re-introduced recently by PANCHERZ and thisrecently by PANCHERZ and this is theis the only FIXED FUNCTIONALonly FIXED FUNCTIONAL APPLIANCE.APPLIANCE. The appliance requiresThe appliance requires little patient compliance and produceslittle patient compliance and produces a highly variable mixture of skeletala highly variable mixture of skeletal and dental changes.and dental changes.www.indiandentalacademy.comwww.indiandentalacademy.com
  • 68. FIXED APPLIANCEFIXED APPLIANCE According to angle, the firstAccording to angle, the first importance in the evolution of fixedimportance in the evolution of fixed orthodontic appliance was the “BOWorthodontic appliance was the “BOW OF FAUCHARD” of france. This bowOF FAUCHARD” of france. This bow ,affixed to the external surface of the,affixed to the external surface of the teeth, was the forerunner of the modernteeth, was the forerunner of the modern archwire.archwire. MAGILL was the first to use a plainMAGILL was the first to use a plain band cemented to the tooth by oxy-band cemented to the tooth by oxy- chloride of zinc cement.chloride of zinc cement. It was on the foundation of theIt was on the foundation of the circumferential archwire and the plaincircumferential archwire and the plain cemented tooth band that moderncemented tooth band that modernwww.indiandentalacademy.comwww.indiandentalacademy.com
  • 69. THE COMING OF A NEWTHE COMING OF A NEW AGEAGE AS we enter the1990s we look backAS we enter the1990s we look back on that century in terms of various typeon that century in terms of various type of overallof overall innovations.innovations. We had the auto,We had the auto, aviation, polymer, nuclear, space, andaviation, polymer, nuclear, space, and computer ages. Indeed, it has beencomputer ages. Indeed, it has been said that more knowledge wassaid that more knowledge was amassed in the 20amassed in the 20thth century than in allcentury than in all previous centuries ofprevious centuries of mankind.mankind. AndAnd what we learn about orthodonticwhat we learn about orthodontic materials comes from many of thosematerials comes from many of those burgeoning fields. From the viewpointburgeoning fields. From the viewpoint of true esthetics– in other wordsof true esthetics– in other wordswww.indiandentalacademy.comwww.indiandentalacademy.com
  • 70. from the viewpoint of not making thingsfrom the viewpoint of not making things smaller but of making them TOOTH-smaller but of making them TOOTH- coloured. Practitioners assert thatcoloured. Practitioners assert that estheticsesthetics are desirable but thatare desirable but that functionfunction isis paramount.paramount. And so weAnd so we close this century we begin to seeclose this century we begin to see attempts to market a continuous fiberattempts to market a continuous fiber composite, success to manufacturecomposite, success to manufacture CP-titanium and its products andCP-titanium and its products and modifications to improve slidingmodifications to improve sliding mechanics through ceramic-bracketmechanics through ceramic-bracket inserts and self-ligating brackets.inserts and self-ligating brackets. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 71. CONCLUSIONCONCLUSION ORTHODONTICS has achieved theORTHODONTICS has achieved the status of a recognized specialty ofstatus of a recognized specialty of dentistry because of a long period ofdentistry because of a long period of craftsmanship and professionalcraftsmanship and professional expertise.expertise. While it appears that a certainWhile it appears that a certain stagnation has set in the otherstagnation has set in the other specialties of dentistry at this time ,specialties of dentistry at this time , that is not to be perceived inthat is not to be perceived in orthodontics, where a great deal oforthodontics, where a great deal of development is still going on.development is still going on.www.indiandentalacademy.comwww.indiandentalacademy.com
  • 72. Orthodontics, and indeed all of dentistryOrthodontics, and indeed all of dentistry if it is to survive as a profession mustif it is to survive as a profession must continually re-examine its history andcontinually re-examine its history and find relevant and significant ideals tofind relevant and significant ideals to meet the crisis of today.meet the crisis of today. www.indiandentalacademy.comwww.indiandentalacademy.com
  • 73. www.indiandentalacademy.comwww.indiandentalacademy.com Thank youThank you For more details please visitFor more details please visit www.indiandentalacademy.comwww.indiandentalacademy.com