Downloaded 12 times
More Related Content
![Dental Casting alloys [DENTAL MATERIALS]](https://cdn.slidesharecdn.com/ss_thumbnails/castingalloysbp-200331155134-thumbnail.jpg?width=640&height=640&fit=bounds)
Similar to Direct Filling Gold
![Gold is still best [autosaved]](https://cdn.slidesharecdn.com/ss_thumbnails/goldisstillbestautosaved-170621142826-thumbnail.jpg?width=640&height=640&fit=bounds)
Direct Filling Gold
- 1. “If the romanceof dentistry is ever written “gold foil” will be one of the leading characters……” C.N Johnson Journal of American dental association, Volume 15 page 2051 DIRECT FILLING GOLD- THE KING OF RESTORATIVE MATERIALS
- 2. INDEX-(PART1) • INTRODUCTION • HISTORY •GOLD AS AN ELEMENT AND ITS PROPERTIES • FORMS OF GOLD • INDICATIONS FOR DFG • CAVITY PREPARATION FOR DIFFERENT INDICATIONS OF DFG
- 3. PART 2 • CONCEPTOF COHESIVE, SEMI COHESIVE AND NON COHESIVE GOLD • DEGASSING/ANNEALING OF GOLD • RESTORATION WITH GOLD • FINISHING AND POLISHING • CLINICAL CASES DONE IN THE DEPARTMENT • CONCLUSION
- 4. INTRODUCTION • Among theavailable restorative materials, direct filling gold (DFG) is the oldest filling material that is still being used in restorative dentistry. • The vision to use gold stemmed from the perfect harmony of its biological and mechanical properties, excluding esthetics. • Gold
- 5. HISTORY • 1483- Giovannid arcoll first recommended gold leaf as restorative material • 1712-1786- Frederic used for pulp capping. • Gold foil for restoration purposes was introduced in America by Robert Woffendale in 1795 (Dwinelle and Watts, 1855). . • 1803 –Edword Hudson used goldfoil to fill root canal.
- 6. • Gold leafas a filling became popular in the United States in the early nineteenth century. Marcus Bull of Hartford, Connecticut, began producing beaten gold for dental use in 1812 • In 1840 Jackson first introduced sponge (Crystal or crystalline) gold which was easier to condense. • This was followed by the discovery of cohesive or adhesive properties in gold by American dentist Robert A. Arthur in 1855. • 1896- Bryan referred to mat gold
- 7. • 1964- Goldentpowdered gold was introduced. • 1969 – R.V.Willams and C.Ingersoil introduced Electralloy • 1980- E-Z gold were introduced by Baum. • 1989-new granular type of granular gold “stopF gold” was introduced by Dhiek and Regelstein
- 9. GOLD AS ANELEMENT (AU) • Gold has derived its name from the old english Anglo-Saxon word ‘Geolo’ meaning YELLOW. • The symbol origin is from the latin word ‘Aurum’ meaning “Glowing Dawn” • Atomic number – 79 • Atomic weight – 196.966amu • Melting point – 1064.43ºc • Boiling point – 2807ºc
- 10. PROPERTIES OF GOLD •Cohesiveness to a greater extent than any other metal. • Softness during manipulation: This quality depends mainly on purity of gold • Inertness: A noble metal, gold is most biocompatible and remains stable irrespective of heat, moisture, air, and most solvents. Rarely tarnishes or corrodes in the oral cavity.
- 11. • Malleability: Itmay be reduced by beating to 1/250,000th of an inch in thickness. Reaumur is stated to have produced a sheet 0.00000087inch in thickness. • Ductility: One grain of pure gold may be drawn into a wire nearly 500- feet long. • Hardness in bulk form: Gold is about one third as hard as diamond. This property is largely increased by alloying and hammering or by rolling. Its Brinell hardness number is 48.0, in comparison with copper is (74.0) and silver (59.0)
- 12. • Shore Scleroscopehardness test is associated with the elasticity of the material. Following values were determined by Ward for 24-carat gold: cast gold 4.9, rolled gold 3.0, gold annealed after rolling 5.8. • Tensile strength: Gold is capable of holding a weight of 7 tons per square inch, according to Hiorns.
- 13. • Weldability incold state: Welding of pure gold under pressure can be done at room temperature (cold welding) because of lack of surface oxides on gold. This results in increased strength. • Minimum tendency to flow. • Coefficient of expansion: Coefficient of expansion of gold is 14.4, which is near 11.4, the coefficient of expansion of the enamel.
- 14. • Thermal andelectric conductivity: The thermal and electric conductivity is 53.20 and 77.96. • True density: It is defined as mass divided by volume. True density of pure gold is 19.3 g/cm3 . More the density of gold, lesser will be porosity present in condensed gold thus making the restoration long lasting Journal of gold foil operators,1962
- 15. WHAT MAKES GOLDIN DENTISTRY UNIQUE? can be cold welded adheres to each other at room temperature This, coupled with strain hardening by cold welding increases the strength and hardness of the material makes DFG unique
- 16. PURITY OF GOLD- •The karat system (k) specifies the gold content of an alloy based on parts of gold per 24 parts of the alloy. • Fineness is the unit that describes the gold content in noble metal alloys by the number of parts of gold in each 1000 parts of alloy. 24 karat= pure gold. Pure gold has fineness of 1000
- 17. CLASSICATION (BASED ONMODES OF SUPPLY) I. Foil • A. Sheets • B. Ropes • C. Cylinders • D. Laminated gold • E. Platinized gold • F. Corrugated gold II. Electrolytic precipitate • A. Matt gold • B. Matt foil • C. Gold calcium alloy III. Granulated/Powdered gold
- 18. PHYSICAL PROPERTIES OFDIFFERENT FORMS OF GOLD Richter and Cantwell, Journal of Prosthetic Dentistry (1965)
- 19. GOLD FOIL BASED ONSHAPE- • GOLD SHEETS • ROPES • CYLINDERS BASED ON MANUFACTURING- • CORRUGATED • PLATINIZED • LAMINATED
- 20. GOLD FOIL • Goldfoil sheets are manufactured by a process called gold beating or rolling • All light weight sheets are formed by beating and heavy weight sheets are formed by rolling • In beating process, first heavier mallets are used followed by lighter ones as gold gets thinner. • For rolling, it is passed through rolling mills until desired thickness is got.
- 21. • It comesin a book of 1/10 or 1/20 ounces. • One book has 12 sheets with a common dimension of 4 x 4inch • No. 4 gold foil weighs 4 grains (0.259gm) and is 0.51µm thick • No. 3 gold foil weighs 3 grains (0.194gm) and is about 0.38µm thick.
- 22. Gold foil pellets: •Sizes used are from 1/10 onwards. Larger sizes of 1/2, 1/4, 1/8 are used for making cylinders. The desired piece is then grasped by index, thumb and middle finger of left hand. Ends are touched with tweezers towards the center and are rolled into loose balls .
- 24. Gold foil cylinders- •Can be hand rolled or commercially rolled • Made by rolling the cut segment of No. 4 foil into 1/2, 1/4, 1/8 size cylinders.widths
- 25. Corrugated gold /carbonized gold foil - • This was first observed by a dental dealer in the great Chicago fire of 1871. • Corrugated gold foil is manufactured by placing a thin leaf of paper between two sheets of gold foil, after which the whole container accommodating paper leaves and gold foil is ignited.
- 26. • As thepaper leaves are burned out, they shrivel, and thereby impart a corrugated shape to the gold foil. • It has been proven that corrugated gold foils are more cohesive than the plain ones.
- 27. PLATINISED GOLD FOIL- •It’s a sandwich of gold and platinum with platinum content being 15% • One sheet of platinum foil is sandwiched between two sheets of gold foil and is then hammered to the thickness of NO. 4 gold foil • Platinum increases the hardness and wear resistance of the restoration. So this form can be used in stress concentration areas like incisal edges and cusp tips.
- 28. LAMINATED GOLD FOIL- •When a cube of gold ingot is cold worked in order to formulate a sheet, the cubical crystals of gold will be stretched and elongated in a specific direction. • This cube when viewed under a microscope. It appears fibrous, with the fibers parallel to each other in a specific pattern which will have directional properties, i.e., It will be resistant to stresses in one direction better than the other. Stretching in one direction
- 29. • The ideaof laminated gold foil is to combine two or three leaves of gold, each from different ingots which have been cold worked in different directions. • Laminated gold foil is definitely much stronger and much more resistant to stresses than the other forms of direct gold materials
- 30. ELECTROLYTIC PRECIPITATE GOLD MATGOLD GOLD CALCIUM ALLOY MAT FOIL
- 31. MAT GOLD • Itis an electrolytically precipitated crystalline form that is sandwiched between sheets of gold foil and formed into strips • These strips are cut into desired sizes . • Preferred for its ease in building up the internal bulk of the restoration as it can be more easily compacted and adapted to the retentive portions of the prepared cavity.
- 32. • As itis loosely packed it is friable and contain numerous void spaces between the particles • So it is recommended for the external surface of the restoration • Using this two material technique the mat is covered with veneer of foil • Loosely packed crystalline form with large surface area of the mat powder does not permit easy welding into a solid mass as does gold foil.
- 33. Advantages and indications- • Rapid filling, • Filling Internal bulk (cavity walls ,and retentive portions) • It is used to form the core of the restoration DISADVANTAGES- • Difficult to handle, voids, surface pitting and ditching, rough finish. • More condensation pressure required, crumbles during manipulation • Does not permit welding into homogenous mass.
- 34. MAT FOIL • Thisis a sandwich of Mat Gold placed in sheets of No 3 / 4 gold foil.The sandwich is sintered by heating to just below the melting point of gold and cut into strips of different widths • The gold foil cover holds the crystalline gold together while it is being condensed. INDICATIONS- • Because mat gold foil is highly adhesive and cohesive, and its adaptability it is ideally suited for building up the internal bulk of Class V, Class I and the occlusal portion of Class II restorations. Mat Gold Foil By Koser And Ingraham, Operative Dentistry Vol 52 1956
- 35. ALLOYED ELECTROLYTIC PRECIPITATE •This is an alloy of electrolytic gold and calcium • The calcium content is usually 0.1- 0.5 % by weight • Its purpose is to produce stronger restorations by dispersion hardening. • For convenience, the product is sandwiched between two layers of gold foil
- 36. • ELECTROALLOY R.V. Thisis a mat gold manufactured by Williams Gold Refining Company, New York. R.V stands for R.V. Williams who developed this alloy
- 37. POWDERED GOLD • Itis a blend of atomized and precipitated powder embedded in a wax-like organic matrix. • This form was introduced in 1962 by Baum. • The atomised and chemically precipitated powders are first mixed with a soft wax to form pellets • These wax gold pellets are wrapped with foil making their placement in the cavity easy. • The resulting pellets are cylindrical and are available in different diameters and length.
- 38. • Commercially availablepellets of powdered gold wrapped in a gold foil are known as “ goldent” introduced in 1960’s
- 39. E- Z Gold •It is similar to Goldent but with improved working properties marketed by Williams Gold Refining Company, New York, introduced in the late 1980s • It is a mixture of pure gold powder and wax (less than 0.01% organic wax),wrapped in gold foil. • Its manipulative characteristics are similar to stiff amalgam yet more cohesive than gold foil hence the name e-z gold EZ-Gold The New Goldent By Alperstein , Yearwood Jod 1996,21, 36-41
- 40. • It isrecommended for use in small class-I and class-V LESIONS • It is less time consuming and more predictable. • Greater expected longevity and more favourable tissue response. EZ-Gold The New Goldent By Alperstein , Yearwood Jod 1996,21, 36-41
- 41.
- 42. Gold is thematerial of preference in all Class I cavities, where sufficient access is obtainable. Incipient carious lesions.(Occlusal, buccal, lingual pits)
- 43. Class V inbicuspids, cuspids (where esthetics permit) Class II lesions on premolars and molars
- 44. Class III inmandibular anteriors Erosion areas
- 45. • Atypical lesions Proximal lesions on teeth adjacent to crown preparations Class VI lesions Retrograde root canal filling material A defective margin of an otherwise acceptable cast gold restoration also may be repaired with direct gold.
- 46.
- 47. • Extensive cavitieswith weakened walls • Periodontal weakened teeth • Economy is limited factor • Teeth with large pulp chamber • Root canal treated teeth
- 48. • Under developedroot • Caries prone mouth • Hypersensitive cavities • Lack of skill of operator • Very young and old patient
- 49. ARMAMENTARIUM- • BURS- No. 1round bur,No. 330 or 329 carbide bur-entry Pear shaped bur-Outline form No 331/2 inverted cone bur-Retentive groove Fine acrylic or white stone pear shaped burs-Finishing (Finishing and polishing can also be done with tin oxide and white stone, rubber cups)
- 50. • Hand instruments- GMT-Planning and bevelling of Incisal, lingual, facial, gingival walls. Hatchet-For sharp internal line angles. Hoe- Planning the restoration walls and giving sharp line angles.
- 51. • CONDENSORS • Condensorsare used to deliver forces of compaction to DFG • These condensors have three Parts: • Handle • shank • nib (working end)
- 52. • Round condenser/bayonet condensernib-used in starting, 0.4 to 0.55mm size • Parallelogram and hatchet condenser nib – preliminary condensation, create bulk in restoration,0.5x1mm • Varney Foot condenser nib - has rectangular face,used for bulk built up, 1x1.3mm
- 53. • CONDENSER SHANKS •Available as : straight , monoangle, offset, binangle • Condenser used for hand malleting have longer shank, than condensors used in other mechanical means. Condenser angulation. (A) Monoangled: Perpendicular to the handle. (B) Oblique faced: Angle other than 90° to the handle
- 54. • Force deliveredby compaction is inversely proportional to size of the nib of the condenser. • Smaller the nib face more square inch force is delivered f = 1/d2 (d is reduced by ½, force /square inch delivered by condensation increase by 4 times more)
- 55. • MALLETING- Hand Malleting AutomaticHand Malleting Electric malleting(Mc Shirley condenser) Pneumatic malleting(Hollenback condenser)
- 56. HAND MALLETING- • Oneof the oldest, preferred by most clinicians and requires trained assistant • Correct form of hand malleting requires light force, bouncing application of mallet to condenser rather than heavy blows • Blow must be carefully adjusted it must not be too strong or too heavy. • Mallet must travel parallel to central axis of Handle of condenser • Advantage: greater control of malleting force, varying force are used, rapid change of condenser tip.
- 57. AUTOMATIC HAND CONDENSER •This is a spring loaded instrument • Blows are delivered by releasing a spiral spring • Its main advantage is it gives a series of well regulated blows • Disadvantage: blow descends before full pressure is applied
- 58. PNEUMATIC CONDENSATION • Developedby Dr George. M Hollenback. • Consist of electric engine and air condenser, air is carried through thin tube to hand piece. • Condenser vibrates which is energized by compressed air • Number of blows -360 /min. • Advantage: blow does not fall until pressure is placed on condenser point and continues until released
- 59. ELECTRONIC CONDENSATION • Developedby Mc Shirley • Most efficient and controlled way of condensation • Vibrating condenser head - intensity and amplitude is 20 to 15lbs and frequency of blow is 360- 3600 cycles/min
- 60. • Advantage ofmechanical condensation methods- • Frequency and intensity of blow can be controlled. • Reduced fatigue.
- 61. CAVITY PREPARATION FORDIRECT GOLD RESTORATION
- 62. Class I cavitypreparation- • The outline is similar to class I cavity preparations for amalgam,but with three modifications: • A. Instead of rounded corners in the triangular and linear fossa areas,these preps have angular corners. • B. The extensions in the facial and lingual grooves in molars will end in a spear-like form, i.e., A pointed termination, rather than rounded. • C. The whole outline will look more angular than in preparation for amalgam.
- 63. • Location ofmargins- • The facial and lingual margins of these preparations will be on the inclined planes of the corresponding cusps or marginal ridges, so that the width of the cavity will not exceed 1/5th the intercuspal distance. • The mesial and distal margins will also be conservatively located on the inclined planes. of the corresponding ridge, very close to the adjacent pits
- 64. • Internal anatomy: •The mesiodistal and facio lingual cross section of cavity preparations are very similar to those found in amalgam class-I with two exceptions • The line and point angles are definite and very angular within dentin substance • The cavosurface margins should be beveled with a partial enamel bevel this should be 45º to the direction of enamel rods.
- 65. • Undercuts ifdesired are placed facially and lingually in posterior teeth, and incisally and gingivally on lingual surface of incisors. • Cavosurface bevel- 30-40 degree metal at margin for ease of burnishing the gold. • Bevel - 0.2mm in width.
- 66. Conservative preparation- • Limitedinitial depth is established with No. 330 or No. 329 bur. • When the preparation is extensive because of the inclusion of fissured enamel, a small hoe may be used to complete the desired degree of flatness of the pulpal wall. • With a No. 33 ½ bur at low speed, small retentive undercuts are prepared into the dentinal portion of the external walls at the initial pulpal wall depth; these also may be prepared using a angle-former chisel.
- 67. • Round bursof suitable size are used to remove any infected carious dentin that remains on the pulpal wall. • The preparation is completed by finishing the cavosurface with an angle former, a small finishing bur (e.g., No. 7802), or a flame-shaped white stone
- 68. Class II cavitypreparation- • General shape: • The occlusal outline is an exact replica of the simple Class I cavity preparation in molars and premolars, • Isthumus- reversé S-shaped outline facially and lingually. • The proximal portion outline will be a one-sided inverted truncated cone at the expense of the lingual proximal wall in upper teeth and of the buccal proximal wall in the lower teeth. • In other words, the inverted truncation is at the expense of the functional cusp side.
- 69. • Location ofmargins • Same as class I, there is no need for ‘dove tailing”. • The isthmus portion will have its margins located on the inclined planes of the remaining parts of the marginal ridge and the adjacent cusps, so that the width of the cavity will not exceed 1/5th the intercuspal distance. • There should not be any effort to put the margins subgingivally.
- 70. • INTERNAL ANATOMY •All line angles, with the exception of the axio-pulpal, will be very sharp. • The cavosurface margins are bevelled at almost 45° to the plane of the enamel walls. • The axial wall will be convex, following the curvature of the proximal surface.
- 71. CLASS-III CAVITY PREPARATION •There are three basic designs for class-III preparations: • The Ferrier design • The Loma linda design • The Ingraham design
- 72. • THE FERRIERDESIGN • It is indicated if bulky labial, lingual,and incisal walls remain after removal of all the diseased and undermined tooth structure. • Or if the labial extension of the lesion facilitates minimal extension of cavity preparation labially. • General shape: • Its outline is triangular in shape involving about 2/3rd’s to one half of the proximal surface
- 73. • No 33½ bur or suitable Wedelstaedt chisel –used from facial aspect to position the gingival outline and the facial wall. • Planning the labial wall and incisal out line with chisel. • Planing the incisal wall with angle former
- 74. • Establishing thelingual wall with chisel. • Removal of the linguogingival bulk with inverted cone bur (33½) • Planing the the gingival wall and labial wall to establish the résistance form using 6 ½-2 ½ -9 ½ hoe.
- 75. • Hoe isused to planning the lingual wall and sharpening linguogingival line angle and linguogingivoaxial point angle. • Axial wall is planed with hoe to give convex surface
- 76. • Small angleformer completes the sharp point angles and acute axiogingival angle. • Bibeveled hatchet(3-2-28)- establishes the incisal retentive angle with chopping motion.
- 77.
- 78. • Gingival marginsof the Loma-Linda preparation are similar to the Ferrier design • Labial margins, in some situations, may be located in the contact area, making the restoration completely inconspicuous
- 79. • INGRAHAM DESIGN •This preparation design is indicated primarily for incipient proximal lesions in anterior teeth where esthetics is the main concern. • After removal of diseased and undermined tooth structure, this preparation design will accommodate bulky gingival and incisal walls. Good oral hygiene, low caries and plaque indices are essential indications due to the outline of this design. • This preparation is a simple parallelogram in shape.
- 81.
- 85. MODIFICATIONS OF CLASSV FERRIER PREPARATION
- 87. PART 2 • CONCEPTOF COHESIVE, SEMI COHESIVE AND NON COHESIVE GOLD • DEGASSING/ANNEALING • RESTORATION WITH GOLD • FINISHING AND POLISHING • CLINICAL CASES DONE IN THE DEPARTMENT • CONCLUSION TO BE CONTINUED
- 88.
- 90. • Lamp shouldnot run out of fuel during procedure • There should be no surface contaminants on lamp and wick should be properly trimmed and rounded to produce a tear drop flame • Sulphur in matches could adhere to the wick and contaminate the gold. Its recommended to ignite with other end of the match.