Direct filling gold in endodontics in dentistry.pptx

Direct filling of gold in endodontics

1. DIRECT FILLING GOLD

2. INTRODUCTION Among the available restorative materials, direct filling gold is the oldest filling material that is still used in restorative dentistry. The vision to utilize the noble metals for the replacement of lost tooth structure stemmed from perfect harmony of its biological and mechanical properties .

3. While most of metals can be welded and alloyed at a temperature above the room temperature, the pure gold can be cold welded and made to adhere to each other at room temperature.

4. PROPERTIES Gold (Au) Atomic number – 79 Atomic weight – 196.966amu Melting point – 1064.43ºc Boiling point – 2807ºc Brinell’s hardness number – 25 Malleability - It exceeds all other metals in this respect. It may be reduced by beating to sheets of 1/250,000 of an inch in thickness. Ductility-It is most ductile of all metals

5. INDIC A TIONS Incipient carious lesion Occlusal, buccal, lingual pit Class II lesions on premolars and molars Class III in mandibular anteriors Class V in bicuspids, cuspids (where esthetics permit) Erosion areas Repair of defective cast margins

6. Atypical lesions Proximal lesions on teeth adjacent to crown preparations Class VI lesions Retrograde root canal filling material

7. CONTRAINDICATIONS Very young and old patient Teeth with large pulp chamber Periodontal weakened teeth Economy is limited factor Handicapped patient Root canal treated teeth

8. Under developed root Caries prone mouth Hypersensitive cavities Extensive cavities with weakened walls Lack of skill of operator

9. AD V AN T AGES Insoluble in oral fluids More resistant to tarnish and corrosion Perfect adaptation to cavity wall because of ductility More edge strength Low tendency to molecular change (free from shrinkage or expansion) Maintain high polish

10. No intra cement substance needed Thermal expansion similar to dentin Oral tissue accepts readily Causes no tooth discoloration

11. DISADVANTAGES Inharmonious color Thermal conductivity can be a problem in a newly restored teeth. Can lead to sensitivity to hot and cold Technical difficulties in forming a dense restoration

12. Manipulation of gold is difficult to master. It requires skill and practice  It is not indicated on surfaces subjected to stress of mastication or for contour work

13. Energy of condensation which is not absorbed by the restorative material, may dissipate to the pulp dentin organ Thermal energy in the pellet, exceeding that needed for decontamination – causes pulpal irritation Frictional heat of finishing and polishing Galvanic current between gold and other metallic restorations Ultrasonic energy from high condensation frequency can harm pulp BIOLOGICAL CONSIDERATIONS

14. 3mm or more of remaining dentin thickness – no base 2mm or more of remaining dentin thickness – varnish on walls and floors, without cavo surface margins Between 1-2mm of remaining dentin thickness – sub base of cal c ium hydroxide or un m odified zinc oxide eugenol and over this varnish is applied. and zinc phosphate cement or zinc poly carboxylate base is used . Less than 1mm of remaining dentin thickness – direct filling gold contraindicated Need for base

15. GOLD - TYPES GOLD FOIL ELCTROLYTIC PRECIPITATED GOLD Mat gold Mat foil Gold calcium alloy POWDERED GOLD/GRANULATED GOLD Gold dent

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17. GOLD FOIL Oldest Manufacture:A cast ingot of 15 mm thickness is beaten to a submicroscopic thickness of 15 or 25 µm Supplied as:FIat square sheets of varying thickness. No. 4 wt. 4 grains (0.259 gram) 0.51 µm thick. No. 3 wt. 3 grains (0.194 gram) 0.38 µm thick.

18. Gold foil pellets: May vary from ½ - 1/128th of a portion of No. 4 gold foil After removing the gold foil along with the tissue paper from the book. Foil is held on paper and is cut to the size needed. Paper supports the thin gold foil and prevents it from tearing and wrinkling during manipulation

19. 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 Pellets are degassed and stored in separate compartment

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21. Gold cylinder Can be hand rolled or commercially rolled Made by rolling the cut segment of No. 4 foil into 1/2, 1/4, 1/8 widths D r . M adhuBi l la

22. Corr u gated gold / c a rb o nized 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. As the paper 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.

23. Platinized Foil Pure platinum foil sandwiched b/w two sheets of pure gold Bonded by cladding process Increases hardness Available in No. 4 sheet form

24. When a cube of gold ingot is cold worked in order to formulate a sheet, the cubical crystals of gold will he stretched and elongated in a specific direction. this type of gold foil material will have directional properties, i.e., It will be resistant to stresses in one direction better than the other. LAMINATED GOLD FOIL

25. The idea of laminated gold foil is to combine two or three leaves of gold, each from different ingots which have been cold worked in different directions. Therefore, laminated gold foil is definitely much stronger and much more resistant to stresses than the other forms of direct gold materials.

26. Cohesive & Non-Cohesive Gold Cohesive: For cold welding gold should have a clean surface Gold attracts gases and any absorbed gas film prevents cohesion of individual increments of gold Cohesive gold is supplied free of contaminants Non-Cohesive: Gold is subjected to volatile agent such as ammonia, which is absorbed on surface Acts as a protective film Volatile film readily removed by heating Rarely used nowadays

27. ELECTROLYTIC PRECIPITATE  Crystalline gold powder is formed by electrolytic precipitation. Powder is formed into shapes by sintering(heat fusion).  Available as: mat, mat foil & alloyed  Mat gold: Crystalline Formed in strips Easy to build up the internal bulk, more easily compacted & adapted Results in pitted external surface, so covered with a veneer of foil gold  Mat foil: Sandwich of electrolytic precipitated gold powder b/w sheets of No.3 gold foil

28. Advantages: Rapid filling, Filling Internal bulk (cavity walls ,and retentive portions) It is used to form the core of the restoration Average size is 10 to 20µm

29. Disadvantage s: Difficult to handle, Voids ,surface pitting, and ditching, rough finishing, More condensation pressure required, crumbles during manipulation Does not permit welding into homogenous mass

30. POWDER GOLD  Gold powder is enclosed in a No.3 gold foil  Manufacture: Fine powder is formed by chemical precipitation or atomizing the metal Pellets mixed with soft wax, burned off later & wrapped in gold foil  Available as: Foil acts as an effective container and matrix for the powdered metal Powdered gold pellet increases cohesion & reduces time required for placing it Powdered gold pellets have cylindrical or irregular shape & diameter of 1 – 2mm

31. Done to eliminate the need to veneer the restoration with a layer of foil No longer marketed

32. Alloyed Electrolytic Precipitate: Newest form is Electraloy RV Alloy of gold & calcium (0.1 to 0.5% by wt) Calcium produce stronger restoration by dispersion strengthening Alloy sandwiched b/w two layers of gold

33. REMOVAL OF SURFACE IMPURITIES /ANNEALING HEAT TREATMENT/DEGASSING  Degassing -Remove the surface impurities (ammonia gas, wax ,other gas) Annealing: Remove the surface impurities with internal stress relief, restores ductility and malleability Annealing temperature ranges from 650°to 700°c,depended on selected method and heating time Produce an atomically clean surface result in metallic bonding

34. 1. OPEN ALCHOHOL FLAME METHOD Also called as piece method Heating unit used is open flame Absolute or 90% ethyl / methyl alcohol without any additives was used to produce a clean blue flame Gold foil is held with a instrument and heated over a clean blue flame of absolute alchohol METHOD OF DEGASSING

35. Gold is passed over the blue flame ( reducing zone/middle zone) for 3-5 sec Temperature of the flame is 1300ºF and heating is done until gold becomes dull red Advantages: Less contamination Less wastage of the material Desired size of piece can be selected Disadvantages: Time consuming.

36. 2.BULK METHOD MICA TRAY OVER A FLAME METHOD: A sheet of mica can be used over any type of flame and is used somewhat as a heating element. Divide the surface of the mica into several areas to indicate the time the pieces of gold were put on the mica Maximally five minutes are allowed for any piece of gold to be heated on mica Degassing of several gold pellets at the same time is possible

37. ELECTRIC ANNEALING This is the most controlled and standardized way of decontaminating gold materials. With this instrument, the heated compartment area is made of aluminum. An electric heater controls the time and the temperature. The surface of the heater is divided into small compartments. each accommodating a piece of direct gold. This eliminates the possibility of cohesion of the pieces before they are inserted into the cavity preparation. Maximally, five minutes are allowed for any piece to be kept in the electric decontaminator.

38. Electric annealing is maintained at temperature 343degree C (640 F)- 371degree C (700 F) Used for powdered gold to burn away wax Disadvantage: stick together if the tray is moved, size selection among the piece of degassed gold is limited , more chance of contamination .

39. degassing UNDERHEATING Incomplete cohesion. Pitting and flaking of the surface. OVERHEATING more stiffness less ductile difficult to condense, non cohesive particles adhere to each other excessive sintering

40. Condensation /compact ion Objectives: Two main processes which control the quality of final direct gold restorations are welding and wedging. Welding: process of forming atomic bonds between pellets, layers of gold as a result of compaction Wedging: process of pressurized adaptation of gold form within the space betwee n tooth structure walls or corners minimizing voids between margin of tooth and surface of gold.

41. PRINCIPLES OF CONDENSATION  1. Force of condensation must be 45° to the cavity walls and floors,  Bisect the line angle and trisect the point angle (result in maximum adaptation ,minimum irritation to vital pulp and dentin

42. forces of condensation must be directed at 90 degrees to previously condensed gold always start at point angle on one side and proceed to other side. (tie formation) Ensure condenser has covered entire piece of gold Condenser has to over lap at least ½ of the previously condensed area

43. 4. use minimum thickness of pellet as possible 5 Energy of condensation : Less energy is used inside cavity preparation Gradually increase the energy of condensation as build up proceeds to surface Maximum energy is used at surface of restoration

44. 6. Condensation can be either from one periphery of the increment to other or preferable from center of the increment to periphery (reduces voids , air entrapment)

45. COND E NSERS Condensors are used to deliver forces of compaction to DFG These condensors have three Parts: Handle shank, nib (working end)

46. CONDENSER NIB: Com m on fea t ure of a l l Con d enser are faces are serrat e d with pyramidal shape configuration Conensors based on Shapes of nib: Round condenser/bayonet condenser -used starting, nib face is 0.4 to 0.55mm Para l l e log r am a n d hat c het c o n denser - p rel i m inary condensation, create bulk in restoration, nib face is approximately 0.5x1mm V arney F o ot co n dens e r - has rec t angu l ar face, i t m e asur e s approximately 1x1.3mm - used for bulk built up

47. CONDENSER SHANKS Available as : straight , monoangle, offset, binangle Condenser used for hand malleting have longer shank, than condensors used in other mechanical means.

48. Force required for compaction is proportional to size of nib of the condenser. Force delivered by 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)

49. There are several methods for the application of these forces: Hand pressure Hand malleting Automatic hand malleting Electric malleting Pneumatic malleting

50. METHODS OF CONDENSATION 1.Hand pressure condensation Used as first step in 2 step condensation as Initial confinement of material within the cavity, Compaction method is similar to amalgam condensation except force and duration of force is more

51. 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

52. CONDENSATION BY HAND MALLEATING One of the oldest, preferred by most clinicians Requires trained assistant Correct form of hand malleting : requires light force , bouncing application of mallet to condenser rather then delivering 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.

53. CONDENSATION BY MECHANICANAL MEANS consist of condenser with working tip and short shank (<1 inch ) with fits into malleting hand piece (either straight or right angled hand pies) Advantage: frequency and intensity of blow can be controlled reduced fatigue Types: a.Pneumatic condensation-Hollen back b. el e ct r D o r . M n a d i h c uB i c l l a onden s atio n - Mc S h irley

54. A.PNEUMATIC CONDENSATION Developed by Dr George. M Hollen back 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

55. B. ELECTRONIC CONDENSATION : Developed by Mc Shirley Most efficient and controlled way of condensation V ib r at i ng condens e r head - in t ens i ty and a m pl i tude is 20 to 15lbs and frequency of blow is 360- 3600 cycles/min Dr.MadhuBilla

56. General steps for insertion of DFG into tooth preparation A. Three steps building up for the restoration Tie formation – is connecting two opposite point angles with a transverse bar of gold. This ‘tie’ forms the foundation of any direct gold Banking of walls – covering each wall from its floor ,Or axial wall to cavosurface margin with direct gold. The wall is banked without obstructing tie formation or banking of other walls. It is done simultaneously on other walls too. Shoulder formation – to complete a build up, two opposing walls are connected with direct gold

57. Paving of the restoration Every area of cavosurface margin is individually covered with excess gold foil . Condensation from center to periphery is better than periphery to center, since it decrease the trapped air bubbles Surface hardening of restoration  Utilizes the high condensation energy in the restorative procedure, so as to strain harden the surface gold and fulfill the objectives of restoration

58. 4 . Burnishing This is done with a suitable burnisher moving from the gold to the tooth surface. This enhances the surface hardening and also produces good marginal adaptation of the gold. 5 . Margination: This step uses sharp gold knives to remove excess gold from the surface to the tooth.

59. 6. burnishing: It is important to burnish the surface of gold restoration after margination so as to eliminate marginal discripencies and to strain harden the surface. 7. Contouring : This step uses knives, files or finishing burs to create the proper occlusal anatomy.

60. 8 . finishing and polishing : Direct gold restorations require very little finishing if the previous steps are properly done. It can be done by using tin oxide powder on soft bristle brushes or rubber cups. 9 . final burnishing: This is done after polishing to make the surface of the restoration smooth and free from voids.

61. CAVITY PREPARATION FOR DIRECT GOLD RESTORATION D r . M adhuBi l la

62. Class I cavity preparation

63. SIMPLE CLASS-I DESIGN  I. General shape The outline is similar to class I cavity preparations for amalgam, but with three modifications: Instead of rounded corners in the triangular and linear fossa areas, these preps have angular corners. 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. The sweeping curves of the outline form of the cavity preparation compared to those for amalgam are less pronounced. In other words, the whole outline will look more angular than in preparation for amalgam.

64. 2. Location of margins 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. D r . M adhuBi l la

65. 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. D r . M adhuBi l la

66. Complex class-I cavity preparations: D r . M adhuBi l la These are class-I cavity preparations with facial and/or lingual extensions. They will have the same general shape, occlusally, as the simple design. The facial and/or lingual extensions will be parallelogram shape. The location of margins is exactly as in the preparation for amalgam, except the mesio distal width of the facial and lingual portions of the cavity preparation should be very limited (1 mm, if possible). The internal anatomy of these cavities will also be similar to the simple design in their occlusal part. However, it is necessary to have starting points At the mesial and distal axio gingival corners of the facial and lingual extensions And again a partial enamel bevel is mandatory

67. Pulpal floor - 0.5mm into dentin Undercuts if desired 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 D r . M adhuBi l la

68. Class II cavity preparation D r . M adhuBi l la

69. Class-II cavity preparation: D r . M adhuBi l la CONVENTIONAL DESIGN  General shape: The occlusal outline is an exact replica of the simple Class I cavity preparation in molars and premolars, The isthmus portion will definitely have a reversé S-shaped outline facially and lingually due to the very narrow occlusal preparation in transition to a regular size contact area. The proximal portion outline will be a one-sided inverted truncated cone. On the upper teeth, truncation will be at the expense of the lingual proximal wall, and on the lower teeth, truncation will he at the expense of the buccal proximal wall. In other words, the inverted truncation is at the expense of the functional cusp side.

70. Location of margins The occlusal portion will have its margins exactly in the same location as the simple Clãss I on the occlusal surfaces of molars and premolars. However, there is no need for ‘dove tailing” in locating those margins. 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. The margins gingivally will just clear the contact area. There should not be any effort to put the margins subgingivally. D r . M adhuBi l la

71. Internal anatomy D r . M adhuBi l la A. A mesio-distal cross-section enables visualization of the proximal, pulpal. Axial, and gingival walls and floors. They can be seen to have the same angulation as in class II, design I for amalgam. With two exceptions: I. All line angles, with the exception of the axio-pulpal, will be very sharp. Ii. The cavosurface margins are bevelled at almost 45° to the plane of the enamel walls. B. The facio-lingual cross-section at the gingival one-third indicates that the axial wall will be convex, following the curvature of the proximal surface.

72. THE CONSERVATIVE DESIGN: D r . M adhuBi l la The general shape and location of margins are similar to that of amalgam preparations. Internal anatomy Mesio-distal cross section: This section shows a very slanted axial wall, formed of dentin and enamel. The enamel portion is partially beveled towards the occlusal. The gingival floor is in four planes: an internal, reverse-bevel plane, making an acute angle with the axial wall and formed completely of dentin; a transitional plane, formed completely of dentin and slightly flat: an outer, enamel dentinal plane following the direction of the enamel rods and, finally, a partial bevel on enamel only, not to include more than 1/4th of its extent.

73. b. Facio-lingual section: The triangular areas, facially and lingually, will extend to just short of the occlusal enamel, leaving a limited thickness of dentin to support the occlusal enamel. The triangular area joins the reverse bevel internally via a rounded junction. D r . M adhuBi l la

74. SIMPLE DESIGN D r . M adhuBi l la General shape: Similar to that of amalgam except that it has a more angular junction between the different margins Location of margins As the whole surface is self clensible the margins can be placed anywhere on the surface. Internal anatomy: a. An occluso-gingival cross-section will show that the occlusal wall is formed of three planes, one plane in the form of dentin, and at right angle to the axial wall; a second plane inclining occlusal proximally, and formed of enamel and dentin; and a third one in the enamel wall, in the form of a bevel.

75. B. In a facio-lingual cross-section the axial wall will appear to be flat to slightly rounded. The facial and lingual walls will have the same anatomy If the facial and lingual margins are in the middle third of the proximal surfaces of the corresponding walls two internal planes can be combined into one, following the direction of the enamel rods. D r . M adhuBi l la

76. Class V cavity preparation: Ferrier design Outline -trapezoidal Gingival wall and occlusal wall are flat and parallel to occlusal plane Occlusal wall is longer than gingival Mesial and distal walls makes an obtuse angle with the gingival wall and an acute angle with the occlusal wall D r . M adhuBi l la

77. Mesiodistally axial wall c an be curved so as to prevent encroachment on the pulp But excessive curvature results in preparation which is too shallow in centre or too deep proximally. Axial wall is 1mm deep occlusally and as it comes down cervically, its 0.75mm Mesioaxial and distoaxial line angles are obtuse so as to prevent any undermined enamel and also gives resistance to movement of gold during compaction. D r . M adhuBi l la

78. The mesial and distal walls provide resistance for gold compaction, but they don’t give retention. Retention is provided by sloping of the gingival wall internally to meet axial wall in a sharp defined acute axio gingival line angle . Retention so is achieved by facial convergence of occlusal and gingival walls. Where gingival margin is on enamel, cavosurface is beveled , when it is on cementum, its not beveled Hoe is used for planning the restoration walls and giving sharp internal line angles D r . M adhuBi l la

79. According to the caries extent, different designs of Class-V preparation can be made. Semilunar shaped cavity Class V with uni or bilateral mustache extension Parallelogram in design Class V with proximal pen handle extension D r . M adhuBi l la

80. FERRIER DESIGN PEN HANDLE EXTENSION CRESENT MOON SHAPED UNI & BI LATERAL MOUS D T r.M A a C dh H uB E illa EXTENSION

81. CLASS-III CAVITY PREPARATION D r . M adhuBi l la There are three basic designs for class-III preparations: The Ferrier design The Loma linda design The Ingraham design

82. THE FERRIER DESIGN D r . M adhuBi l la It is indicated if after removal of all the diseased and undermined tooth structure, bulky labial, lingual,and incisal walls remain Furthermore it is indicated if the labial extension of the lesion facilitates minimal extension of cavity preparation labially. General shape: Its outline is triangular in shape involving about 2/3 rd ’s to one half of the proximal surface LOCATION OF MARGINS: Being a labial and lingual cavity the labial and lingual margins should be within corresponding embrasures

83. Internal anatomy: In labiolingual cross section it can be seen that the axial wall is rounded but not following the convexity of proximal surface. In the inciso gingival cross section the incisal wall appears as in class v cavity preparation i.e. Formed of three or four planes All the line angles and point angles should be sharp with exception of junction between the line angles of the cavity preparation proper and those of retention forms which should have a rounded junctional relationship. D r . M adhuBi l la

84.  INSTRUMENTATION No 33 ½ 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 wedelstaedt chisel Planing the incisal wall with angle former D r . M adhuBi l la

85. Establishing the lingual wall with wedelstaedt 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 D r . M adhuBi l la

86. Hoe is used to planning the lingual wall and sharpening linguogingival line angle and linguogingivoaxial point angle Axial wall is planed with hoe to give convex surface D r . M adhuBi l la

87. Small angle former- complete the sharp point angles and acute axiogingival angle Bibeveled hatchet (3-2-28)-establish the incisal retentive angle with chopping motion D r . M adhuBi l la

88. LOMA-LINDA DESIGN: This design is indicated for a combination of powdered gold build-up with a cohesive gold foil veneer. It is used when access to the lesion is lingual, as dictated by esthetics and the caries extent, or when the lingual marginal ridge is lost or undermined. General shape: The proximal part of this cavity design will be triangular with rounded corners. The lingual part may have an incisal or gingival “turn” as dictated by access and resistance form D r . M adhuBi l la

89. Location of margins: Gingival margins of 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. However, the labial margin will usually have the same locations and specifications as in the Ferrier design. The lingual margin will be located far enough onto the lingual surface to include the marginal ridge and to facilitate access to the internal parts of the cavity preparation. D r . M adhuBi l la

90. Internal anatomy: D r . M adhuBi l la Inciso-gingival cross-section: The loma-linda design appears to have the same anatomy as the incisal gingival section of the ferrier design, except the line and point angles are more rounded. Also, the incisal internal retention mode appears bulkier than in the ferrier design. Labio-lingual cross-section: if the labial margin is located in the contact area. The labial wall will be formed of two planes: an enamelo-dentinal plane at right angle to the axial wall following the directions of the enamel rods and a partial enamel bevel plane.

91.  The point angles gingivally accommodate two cylindrical retention grooves. They will be directed labio-gingivo-axially and linguo-gingivo-axially extending about 1.5-2 mm into the dentin. The incisal retention mode is directed inciso-labio-axial and is cylindrical in form. D r . M adhuBi l la

92. 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. D r . M adhuBi l la

93. General shape: This preparation is a simple parallelogram in shape. Location of margins: The labial margin of the ingraham design will be in the contact area, so it is truly invisible labially. The gingival margin just clears the contact area in the gingival embrasure without any predetermined relationship to the gingiva.  The incisal margin will be within the contact area. The lingual margin will be on the lingual surface past the marginal ridge, and/or axial angle of the tooth. D r . M adhuBi l la

94. INTERNAL ANATOMY: D r . M adhuBi l la INCISO-GINGIVAL CROSSSECTION: At the very labial one-third of the cavity the gingival wall will have three planes. An internal dentinal plane, part of a wall accommodating triangular retention mode, and, inclining apically. An outer enamelo-dentinal plane following the direction of the enamel rods; and a peripheral partial enamel plane bevel. the axial wall will appear to be perfectly flat. the incisal wall will have the same anatomy as the gingival wall, but in the reverse direction. Labio-lingual crosssection: The axial wall appears perfectly flat, opening directly to the lingual surface and making a right angle with the labial wall.

95. High quality direct-gold restorations can be ensured only when four principal conditions are satisfied: D r . M adhuBi l la The appropriate gold form is used for each specific clinical situation. The material is used only where it is indicated. A perfectly dry and clean field is provided. The material is properly manipulated with the correct instruments. Philips Textbook of dental materials 11 th ed

96. CONCLUSION D r . M adhuBi l la  The option to utilize gold foil as the best restoration totally rests on the shoulder of the operator. Unless a conservative dentist takes a conscious attempt to learn and master this wonderful material and technique for many indicated lesions, the patient will be deprived of the very best treatment because of the fallacy of the conservative dentist .

97. THANK YOU….. D r . M adhuBi l la