Retainers in FIXED PARTIAL DENTURES(FPDS) AND RESIN BONDED FPD

DIFFERENT RETAINERS IN FPD ARE DISCUSSED WITH PICTURES AND REFERENCES AND SPECIAL CONSIDERATION FOR RESIN BONDED FPDS PARTIAL COVERAGE RESTORATIONS AND INTRACORONAL RESTORATIONS

1. RETAINERS IN FPD NAMITHA.AP 2 ND MDS DEPT.OF PROSTHODONTICS

2. CONTENTS INTRODUCTION CLASSIFICATION OF RETAINERS REQUIREMENTS FACTORS AFFECTING SELECTION OF RETAINERS EXTRACORONAL RETAINERS FULL VENEER CROWNS PARTIAL VENEER CROWN RETAINERS RESIN BONDED RETAINERS INTRACORONAL RETAINERS RADICULAR RETAINERS CONCLUSION REFERENCES

3. Introduction unites the abutment(s ) to the remainder of the restoration Nallaswamy D. Textbook of prosthodontics. JP Medical Ltd; 2017 Sep 30.642 Retainer is a crown or any restoration that is cemented to the abutment medium through which mechanical and physical forces are translated into physiological functions and biological reactions in living tissues. Tylman SD. Theory and practice of crown and fixed partial prosthodontics (bridge). CV Mosby; 1970.170

4. The Ideal Retainer least amount of tooth cutting and mutilation of tooth contour and the least number of surfaces Accurate m arginal line without trauma to the pulp or surrounding tissue Functional adaptation and protect the tooth against its fracture Cleansable Esthetic does not corrode or tarnish; neither does it discolor the abutment; capable of being prepared by the average operator Rigidity to withstand requisite load Tylman SD. Theory and practice of crown and fixed partial prosthodontics (bridge). CV Mosby; 1970.173

5. Factors affecting selection of retainers Tylman SD. Theory and practice of crown and fixed partial prosthodontics (bridge). CV Mosby; 1970.174

6. CLASSIFICATION OF RETAINERS BASED ON LOCATION Tylman SD. Theory and practice of crown and fixed partial prosthodontics (bridge). CV Mosby; 1970.173

7. BASED ON TOOTH COVERAGE TWO OR MORE SURFACES INVOLVED ALL FIVE SURFACES INVOLVED Tylman SD. Theory and practice of crown and fixed partial prosthodontics (bridge). CV Mosby; 1970.345

8. BASED ON MODE OF RETENTION Tylman SD. Theory and practice of crown and fixed partial prosthodontics (bridge). CV Mosby; 1970.174

9. BASED ON MATERIAL BEING USED

10. Tylman SD. Theory and practice of crown and fixed partial prosthodontics (bridge). CV Mosby; 1970.172,176

11. Full coverage retainers F abricated like a cap for extensively damaged teeth most retentive and ideal retainers can resist masticatory forces in all directions Tylman SD. Theory and practice of crown and fixed partial prosthodontics (bridge). CV Mosby; 1970.173

12. All metal retainers All ceramic retainers Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan. 352,383

13. ALL METAL RETAINERS Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.204, 211)

14. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.202,204)

15. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.215) PREPARATION

16. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.214)

17. METAL CERAMIC RETAINERS Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.225,229)

18. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.228)

19. ALL CEARMIC RETAINERS Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.264,271)

20. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.271)

21. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.263)

22. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.264,265)

23. PARTIAL COVERAGE RETAINER Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 388 intact surface of tooth structure should not be covered by a crown if its inclusion is not essential to the retention, strength, or esthetic result of the definitive restoration. technician can’t exactly duplicate texture and appearance of untouched enamel. A full coverage crown is about 2.5 times as likely to have a pulpal problem as One with a partial coverage crown conservative restoration Gingival health - supragingival margin

24. TYPES OF PARTIAL COVERAGE RETAINERS Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 401

25. Advantages Margin is accessible to the dentist for finishing and to the patient for cleaning. Less restoration margin is in proximity to the gingival crevice, reducing the possibility of periodontal irritation. An open-faced partial coverage crown is more easily seated completely during cementation, whereas a full coverage crown tends to act like a hydraulic cylinder containing a highly viscous fluid With some of the margin visible, complete seating of a partial coverage crown is more easily verified. If an electric pulp test ever needs to be conducted on the tooth, a portion of enamel is unveneered and accessible. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,388 Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.230)

26. preparation feature must be substituted to compensate for the retention and resistance lost when an axial surface is not covered . most commonly used feature is a groove (maximum effectiveness- grooves must have definite lingual Walls) Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,389

27. INDICATIONS Intact or minimal restored teeth Normal anatomic clinical crown Teeth with adequate labiolingual thickness CONTRAINDICATIONS Teeth with short clinical crowns Thin teeth bucco-lingually Teeth that are proximally bulbous Poorly aligned tooth Bad oral hygiene and high caries index Retainers for long span bridges Endodontically treated teeth Malformed teeth Are not as retentive as complete coverage retainers. There is a limited display of metal. Tooth preparation is difficult because only limited adjustments can be made in the path of placement. DISADVANTAGES Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.240)

28. Maxillary posterior three quarter crowns Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.241)

29. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.243,244)

30. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.245) Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 398

31. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.246,247) MAXILLARY MOLAR

32. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,399 T hree-quarter crown preparation on a mandibular molar or premolar many features found in the preparation of a maxillary tooth biggest difference is the location of the occlusal finish line on the facial surface, which is gingival to occlusal contacts. serves the same purpose as the offset on the maxillary preparation, tying the grooves together and strengthening the nearby facio-occlusal margin. There is no need for an offset on the lingual inclines of the mandibular facial cusps.

33. MANDIBULAR POSTERIOR TEETH THREE QUARTER CROWN Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.248)

34. Three quarter crowns with proximal boxes more retentive than a standard preparation with grooves but boxes are very destructive. justified only if there has been proximal caries or previous restorations. A less destructive way to augment retention and resistance is to use four grooves which is not significantly less retentive than two boxes Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,399

35. Seven eighth crowns Vertical distofacial margin is positioned slightly mesial to the middle of the facial surface Esthetics are good because the veneered distofacial cusp is obscured by the mesiofacial cusp. resistance is better than that of the three-quarter crown. A ccessible location of the distofacial finish line makes the preparation easy to perform. Margin finishing by the dentist and cleaning by the patient are also facilitated . Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,400 Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.247 )

36. U sed on any posterior tooth needing a partial coverage restoration where the distal cusp must be covered. most commonly used on maxillary molars, but it also can be placed on mandibular premolars and molars. for restoring teeth with caries or decalcification on the distal aspect of the facial surface, and it is an excellent fixed partial denture retainer. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.248)

37. PREPARATION OF SEVEN EIGTH CROWN Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.246)

38. REVERSE THREE QUARTER CROWNS used on mandibular molars to preserve an intact lingual surface abutments with severe lingual inclinations, preventing the destruction of large quantities of tooth structure that would occur if a full coverage crown were used . The grooves at the linguoproximal line angles are joined by an occlusal offset on the facial slope of the lingual cusps. Closely resembles a maxillary three-quarter crown preparation because the axial surface of the nonfunctional cusp is uncovered Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,400

39. PROXIMAL HALF CROWN A heavy channel or occlusal offset connects the grooves to strengthen the disto-occlusal margin. An occlusal isthmus augments retention and rigidity . Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,400 three-quarter crown that is rotated 90 degrees, with the distal rather than the facial surface left intact tilted mandibular molar fixed partial denture abutment A countersink in the distal channel helps resist mesial displacement. excellent hygiene and a low incidence of interproximal caries Blemish on distal surface mesial surface parallels the path of insertion of the mesial abutment . Clearance of 1.5 mm is obtained from occlusal reduction terminates at the distal marginal ridge, with little or no reduction of the mesial cusps Grooves paralleling the mesial surface are placed in the facial and lingual axial walls.

40. short-span fixed partial dentures on restoration- and caries-free abutments. Wellaligned, thick, square anterior teeth with a large faciolingual bulk of tooth structure A well-executed standard three-quarter crown on a maxillary incisor or canine need not show much metal. ANTERIOR THREE QUARTER CROWNS Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,402

41. RESTORATION WITH MINIMAL DISPLAY OF METAL If the grooves incline labially, the labioincisal corners are overcut, displaying metal. The bases of the grooves then move lingually, becoming shorter and less retentive usually a pinmodified three-quarter crown in which metal coverage is minimized using pins. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,403,404

42. small football-shaped and coarse-grit ballshaped diamonds. Incisal reduction: long needle diamond. Lingual axial reduction: tapered torpedo diamond. Proximal axial reduction: long needle and tapered torpedo diamonds. Axial finishing: fine-grit tapered torpedo diamond. Proximal grooves: no. 169L and 170L burs. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,405,406,407

43. Incisal offset: no. 171L bur. Incisal bevel: fine-grit flame diamond and no. 170L bur. Proximal extensions are done with thin diamonds or hand instruments with a lingual approach to minimize the display of metal. Use of a large instrument or a labial approach will result in overextension and an unsightly display of metal. FINISHING WITH NO.169 L BUR Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,411

44. PIN MODIFIED THREE QUARTER CROWNS E sthetic modification - retainer of choice on unblemished teeth used as fixed partial denture abutments in esthetically critical areas short-span fixed partial dentures splint retainers. repairing incisors and canines with severe lingual abrasion not be used on teeth with caries or restorations, on surfaces that are not to be covered, or in mouths with extensive caries small , thin, malpositioned , or that have large pulps preserves the facial surface and one proximal surface minimal subgingival margins Periodontally preferable to a full crown unsightly display of metal is avoided without resorting to a destructive full veneer metal-ceramic restoration. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,413,414

45. Pins are likely to produce less retention, and pin-retained castings are less retentive than standard three-quarter crowns. Greater the number , depth, or diameter of pins, the greater the retention.39 The pinmodified A n old restoration that was revived in the 1960s by the development of small twist drills to make pinholes and nylon bristles to accurately reproduce them . Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,408

46. PREPARATION OF PIN HOLES These pins should be 4 mm deep for optimum retention and resistance cautious, when extending to the full depth in areas where limited tooth structure is available. followed with a no. 169L carbide bur, which is 0.6 mm in diameter at its tip and has a slight taper so that its diameter approaches 0.9 mm at its widest . Nylon bristles, which are ideally 25 to 50 μm smaller in diameter than the drill , are placed in the pinholes because the pinholes are too small to be reproduced by impression material. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,409

47. The nylon bristles easily placed with a flame, should have a retentive feature on their protruding ends to allow them to be picked up during the impression Impression material surrounds the pin and incorporates it into the impression. When the impression is poured, the nylon bristles protruding from it reproduce the pinholes . A monofilament nylon fishing line cut to an appropriate length and of the appropriate diameter is used. One manufacturer ( Momoi ) sells a 30-lb test monofilament nylon line (Diamond Hi-Catch Leader Line) with a diameter of 0.59 mm, which is 85 μm smaller in diameter than the 0.675-mmdiameter twist drill. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,409

48. Serrated pins produce more retention than smooth pins. Lengths of the same size monofilament nylon line as used for the impression (ideally 25 to 50 μm smaller than the pinholes in the stone cast ), which have been very slightly serrated on the last 2 mm with a bur, are incorporated into the wax pattern . The bur should not be used around the base of the bristles to avoid weak areas there. The pinholes in the cast must first be carefully enlarged by hand-twisting the no. 169L bur so that the bristles will slide into the pinhole and will be removable with the wax pattern. These bristles must also have a retentive feature on their protruding end, placed with a flame, to be incorporated into the wax pattern. The resulting pins in the casting are ideally 50 to 100 μm smaller than the original pinholes in the preparation . In this example, they would be 85 μm smaller. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,413

49. Pins should be at least 2.0 to 3.0 mm long. Adequate pin length is essential to retention, and short pins will cause the failure of a conservative fixed partial denture. These are very destructive failures because the pinholes become channels for oral fluids and microorganisms to penetrate deep into the tooth . Considerable damage may occur before a loose retainer is detected. If adequate pinhole depth is not possible, a different retainer design should be used . Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,414

50. Lingual reduction: small coarse-grit football-shaped diamond. Incisal bevel: medium-grit long needle diamond. Lingual axial reduction: coarse-grit tapered torpedo diamond. Proximal axial reduction: medium-grit long needle and coarse-grit tapered torpedo diamonds. Axial finishing: fine-grit tapered torpedo diamond Proximal grooves: no. 169L and 170L burs. Proximal flares: fine-grit flame diamond and bur. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,416-19

51. PIN HOLES Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,420

52. Ledge, offset, and trough: no. 170L bur. Incisal bevel: fine-grit flame diamond and bur . Pinholes: no. ½ round bur and 0.675-mm twist drill. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,422,423

53. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan,423

54. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.251-253)

55. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.252-254)

56. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.254-255)

57. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.256)

58. PIN LEDGE PREPARATION It is a technique that employs parallel long pins prepared in the lingual or palatal surface of the clinical crown, in order to increase retention of the restoration. • These restorations used the both grooves and pins to improve retention Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.255 )

59. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.256,257)

60. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.257-59)

61. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.259

62. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.260)

63. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.261)

64. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.261)

65. INTRA CORONAL RETAINERS L argely or entirely confined within the contour of the crown and whose retentive forces are effective within the body of the tooth; its exposed surface area is generally less than that lying within the cavity. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 460

66. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 462-65

67. MO INLAY PREPARATION Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 466

68. METAL INLAY VARIATIONS CLASS V INLAY ON MAXILLARY MOLAR CLASS III INLAY ON CANINE CLASS I INLAY ON MANDIBULAR MOLAR Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 467-68

69. MOD ONLAY PREPARATION Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 469-70

70. FEATURES AND FUNCTIONS Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 474 Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 471-72

71. MOD ONLAY PREPARATION Planar occlusal reduction: round-end tapered diamond and no. 171L bur. Functional cusp bevel: round-end tapered diamond and no. 171L bur Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 474

72. OCCLUSAL SHOULDER no. 171L bur. Isthmus: no. 171L bur. Proximal box: no. 169L and no. 170L burs. Proximal flares: flame diamond and flame bur. Gingival bevel: flame diamond and flame bur. Facial and lingual bevels: flame diamond and no. 170L bur. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 475-79)

73. RESIN BONDED FIXED PARTIAL DENTURES development of acid etching of enamel to improve the retention of resin Buonocore in 1955 means of attaching fixed partial dentures to teeth by less destructive means described the attachment of an acrylic resin pontic to an unprepared tooth using a composite bonding resin Ibsen 1974 Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 423

74. Development of resin retained FPDs The addition of a metal substructure and wings, or retainers, extending onto the abutment teeth was a logical progression Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 424 Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.685)

75. BONDED PONTICS The earliest resin-retained prostheses were extracted natural teeth or acrylic teeth used as pontics bonded to the proximal and lingual surfaces of abutment teeth with composite resin. The composite resin connectors were brittle and required supporting wire or a stainless steel mesh framework. These limited to short anterior spans and had a limited lifetime with degradation of the composite resin bond to the wire or mesh and subsequent fracture . presented to patients as short-term replacements. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.685)

76. CAST PERFORATED RESIN-RETAINED FPDS (MECHANICAL RETENTION) expanded to replacement of posterior teeth Perforated retainers were used to increase resistance and retention. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.685)

77. LIMITATIONS Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.685)

78. ETCHED CAST RESIN-RETAINED FPDS (MICROMECHANICAL RETENTION-"MARYLAND BRIDGE") Thompson and Livaditis at the University of Maryland work of Tanaka et al" on pitting corrosion for retaining acrylic resin facings metal etching studies of Dunn and Reisbick developed a technique for the electrolytic etching of Ni-Cr and Cr-Co alloys Doukoudakis et al. stable aqua regia gel was substituted for electrochemical etching McLaughlin Develop a faster technique usingcombined solution of sulfuric and hydrochloric acids Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.675)

79. Advantages The retainers can be thinner and still resist flexing. The oral surface of the cast retainers is highly polished and resists plaque accumulation . Disadvantages Lack of attention to detail can result in electropolishing or surface contamination With time, both severely degrade bond strengths in a moist environment . Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.676)

80. Proper etching requires evaluation of the alloy surface with a scanning electron microscope. Air abrading metal with 250-ìm abrasive increases bonding strength remarkably when used in conjunction with silane Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.677)

81. MACROSCOPIC MECHANICAL RETENTION RESINRETAINED FPDS ("VIRGINIA BRIDGE") " Virginia Commonwealth University School of Dentistry Adequate bond strengths thickness of the casting must be increased to allow for the undercut thickness Moon and Hudgins et al Surface treatments Air abrasion with aluminum oxide prepare Co-Cr castings for bonding with 4-methacryloxyethyl trimellitate anhydride (4-META) resin. Nickel-chromium alloys required oxidation with a dilute solution of sulfuric acid and potassium manganate as well. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.677)

82. “lost salt crystal" technique. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.678

83. An alternative technique for macroscopic retention cast mesh pattern (nylon) on the internal surface of the retainers technique sensitive adequate retention with a resulting thick lingual casting. The cast mesh and the lost salt crystal method have been supplanted by direct adhesion with resin possible for most casting alloys if the correct surface treatment is provided Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.685)

84. CHEMICAL BONDING RESIN-RETAINED FPDS ADHESION BRIDGES adhesive systems for direct bonding of metal Super bond formulation of a methyl methacrylate polymer powder and MMA liquid modified with the adhesion promoter 4-META (4-methacryloxyethyl-trimellitic anhydride) tri- nbutylborane catalyst system ( added to the liquid before combining with the powder ) Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.689)

85. Advantages highest initial bond strengths of any adhesive resin system (base metal alloys) lower elastic modulus and higher fracture toughness when compared to BISGMA-based resin cements ‘ less brittleness and better clinical results with less welladapted castings . Disadvantages Hydrolytic stability of these bonds over time depends on the alloy's Cr-Ni ratio poor clinical results with bonding high gold alloy retainers to abutment teeth Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.690)

86. BISGMA Based composite resin luting cement modified with the adhesion promoter MDP Excellent bonds to airabraded Ni-Cr and Cr-Co alloys as well as tinplated gold and gold palladium-based alloys. tensile bond to etched enamel (10 to 15 MPa) comparable to the traditional BISGMA low-film thickness composites (e.g., Comspan and Conclude). combination of metal electrolytic etching, followed by application of an adhesive such as Panavia, does not improve the tensile bond to the alloy and is actually slightly lower than the bond of Panavia to airborne-particle-abraded sandblasted) base metal alloys Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.690 )

87. The most recent version of Panavia , Panavia F, is a dual cure system (chemical and visible light) that releases fluoride. incorporates a self-etching primer system ( ED Primer ) for bonding to enamel and dentin Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.691)

88. TIN PLATING Tin-plating of noble alloys allows resin-to-metal bond tensile bond strengths only slightly lower than those for either the electrolytically etched or airabraded Ni-Cr-Be alloys (18 to 30 MPa ). However, tensile bond strengths are certainly greater than the bond to etched enamel. particle abrasion of the alloy surface for adequate tin nucleation sites Tin-plating can be completed in the dental laboratory , chairside , or intraorally to achieve metal bonding . Particle abrasion of the alloy surface just before the plating procedure is critically important Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.692)

89. TIN PLATING SYSTEM tin amide solution - applied to the metal surface with a saturated cotton pledget held on the end of a battery-powered probe (4 volts). probe is grounded elsewhere on the metal Tin-plating times are usually 5 to 10 seconds and produce a light gray surface . followed by copious rinsing with water and drying; adhesive resin is then applied. . Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.693)

90. Particle abrasion of the alloy surface with 50 u alumina before bonding or tin- plating not only creates a roughened, higher surface area substrate for bonding , but it also creates a molecular coating of alumina ." The alumina on the surface aids in oxide bonding of the phosphate-based adhesive systems (e.g ., Panavia to alloy surfaces ) Studies of this bonding mechanism are also reinforced by laboratory data on bonding to alumina and zirconia surfaces Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.694)

91. These adhesive systems have now shown nearly the same degree of long-term clinical bonding ( since 1983 in Japan) as the conventional composites on etched metal (since 1981 in the United States). Laboratory data support their efficacy. Favorable findings for direct adhesion to metal make alloy etching and macroscopic retention mechanisms obsolete.'- This simplifies the laboratory and clinical procedures for placement of resin-retained FPDs Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.695

92. Laboratory systems for adhesive bonding resin to metal flame application of a silica-carbon layer to the metal surface. This treated metal is then silane -coated , which provides a surface to which composite resin will bond. The system ( burneraspirator - timer and associated chemistry) was initially marketed to the dental laboratory industry as the Silicoater . evolved to an oven method to bake the silica-carbon layer to the alloy surface and is now called the Silicoater MD system. Subsequently, the critical aspects of sandblasting before treatment in the oven have been investigated Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.696

93. ROCATEC SYSTEM metal surface is initially particle-abraded with 120 um alumina. followed by abrasion with a specialsilicate particle-containing alumina second particle abrasion step deposits a molecular coating of silica and alumina on the alloy surface. Silane is then applied to the surface, making it adhesive to composite resin. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.696

94. DESIGN CONCEPTS cover as much enamel surface as possible, as long as occlusion, esthetics , or periodontal health are not compromised The initial designs of etched cast retainers included an "interproximal wraparound" concept developed to resist occlusal forces and provide a broader area for bonding. Enamel preparations consisted of creating occlusal clearance, placement of occlusal / cingulum rests, and lowering the lingual and proximal height of contour, thus creating proximal extensions Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.691

95. Frameworks should seat in an occlusogingival direction and should have no facial-lingual displacement contemporary design has improved retention with well-placed and precise grooves on abutment teeth Contemporary mouth preparations, in an effort to minimize failures , do not preserve as much tooth structure as their predecessors; nevertheless, they are still limited to enamel and adhere to conservative design principles Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.689

96. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.689)

97. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.690)

98. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.691

99. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.692,693

100. FABRICATION PREPARATION OF ABUTMENT TEETH A distinct path of insertion must exist Proximal undercuts must be removed to provide " planes of metal" on the lingual and proximal surfaces Occlusal rest seats and proximal groove/slots must provide resistance form definite and distinct gingival margin should be established wherever possible anterior teeth - similar in many ways to the lingual reduction of pinledge preparation amount of reduction is less because the enamel must not be penetrated. If necessary, the opposing teeth can be recontoured to increase interocclusal clearance . Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.694

101. Bur selection Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.693

102. Proximal reduction (facial segment): flat-end tapered diamond Proximal reduction (lingual segment): flat-end tapered diamond. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 436-40

103. Lingual axial reduction: round-end tapered diamond Cingulum groove: short needle diamond Proximal groove: short needle diamond Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 440

104. Resin bonded abutment preparation Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 433-36

105. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 435

106. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.695)

107. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.696)

108. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.697)

109. Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.698

110. BONDING THE RESTORATION Rosenstiel SF, Land MF, editors. Contemporary Fixed Prosthodontics-E-Book. Elsevier Health Sciences; 2015 Jul 28.(page no.700

111. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 443,444

112. Shillingburg HT, Hobo S, Whitsett LD, Jacobi R, Brackett SE. Fundamentals of fixed prosthodontics. Quintessence Publishing Company; 1997 Jan.299 and 445,446

113. Intra radicular retainers R etention and resistance to displacement from the prepared root portion of an endodontically treated teeth While the root preparation retains the post, the core establishes retention and resistance for a complete veneer crown that restores the pulp less tooth to normal form and function. post or dowel with an attached core

114. Deutsch AS, Musikant BL, Cavallari J, Lepley JB. Prefabricated dowels: a literature review. Journal of Prosthetic Dentistry. 1983 Apr 1;49(4):498-503.

115. It seems reasonable to concern ourselves with proper diagnosis and meticulous execution of properly designed retainers, rather than to pit one type of retainer against another. After all retainers are our tools like articulators. we must tailor our treatment plan to the specific needs of our individual patient rather than to fit our patient to our favourite method of treatment. CONCLUSION

116. Stokholm R, Isidor F. Resin-bonded inlay retainer prostheses for posterior teeth. A 5-year clinical study. International Journal of Prosthodontics. 1996 Mar 1;9(2). This study evaluated posterior resin-bonded prostheses using inlays as retainers Thirty-nine patients missing at least one premolar or first molar received 51 resin-bonded fixed partial dentures with high noble alloy inlay retainers and a metal ceramic pontic. Resin luting material bonding to the framework was secured by the Silicoating method (24 fixed partial dentures), lost sugar crystal method (13 fixed partial dentures), or tin plating (14 fixed partial dentures). Clinical examinations were performed 1 week, 1 month, 6 months, 1 year, 2 years, and 5 years after cementation RELATED ARTICLES . None of the fixed partial dentures with silicoating or sugar crystal impressions lost retention, whereas two of the tin-plated fixed partial dentures required replacement. Resin-bonded inlay-retained prostheses appear to be a favorable alternative to other types of fixed partial dentures.

117. Trier AC, Parker MH, Cameron SM, Brousseau JS. Evaluation of resistance form of dislodged crowns and retainers. The Journal of prosthetic dentistry. 1998 Oct 1;80(4):405-9. This investigation evaluated the resistance form of abutments of crowns or retainers that have been dislodged to determine the clinical correlation between restoration dislodgment and lack of resistance form in the preparation. Dies were fabricated from single crowns and retainers of fixed partial dentures that came loose and evaluated for resistance form. A total of 44 abutments were evaluated and included 1 incisor, 15 premolars, and 28 molars. Data from a previous study on the percentage of abutments lacking resistance form for restorations leaving a large dental laboratory was used for comparative statistical tests. The clinical dislodgment of cast restorations is associated with the lack of resistance form in the preparations. In this study, there was a relationship between clinical success or failure and the all-or-none nature of resistance form; dislodged crowns come almost exclusively from preparations with tapers that did not provide resistance form

118. Outcome of bonded vs all-ceramic and metal- ceramic fixed prostheses for single tooth replacement. Karl M et al, Eur J Oral Implantol , 2016;9 Suppl 1:S25-44 The conventional treatment of a single missing tooth is most frequently based on the provision of a fixed dental prosthesis (FDPs). to compare resin-bonded, all-ceramic and metal-ceramic FDPs based on existing evidence. Metal-ceramic FDPs still show the highest survival rates of all tooth-supported restorations. Depending on the ceramic system used, all-ceramic restorations may reach comparable survival rates while the technical complications, i.e. chipping fractures of veneering materials in particular, are more frequent. Resin-bonded FDPs can be seen as long-term provisional restorations with the survival rate being higher in anterior locations and when a cantilever design is applied. Inlay-retained FDPs and the use of fiber-reinforced composites overall results in a compromised long-term prognosis. Recently advocated monolithic zirconia restorations bear the risk of low temperature degradation

119. All-ceramic inlay-retained fixed dental prostheses for replacing posterior missing teeth: A systematic review Raquel et al, J Prosthodont Res, 2018 Jan;62(1): 10-23 to evaluate the current status of all-ceramic inlay-retained fixed dental prostheses (CIR-FDPs) for the replacement of posterior teeth. AIM They concluded that, a three-unit CIR-FDP is a viable treatment option for replacing a posterior missing tooth. Appropriate case selection, abutment preparation and luting procedures may be decisive for clinical success. Zirconia-based CIR-FDPs may be recommended for restoring posterior single missing teeth, although the prosthesis/tooth bonded interface has yet to be improved. The addition of lateral wings to the classical inlay preparation seems promising. The weakest parts of CIR-FDPs are the connectors and retainers, while caries and endodontic problems are the most common biological complications. The fabrication of CIR-FDPs with monolithic zirconia may eliminate chipping problems.

120. Predictability of resin bonded bridges – a systematic review Balasubramaniam et al, Br Dent J, 2017 Jun 9;222(11): 849-858 to evaluate the survival rate of resin bonded bridges (RBBs) and understand the relationship between various prognostic factors and survival rate. AIM Debonding of the restoration (78%) is the most common type of failure followed by porcelain fracture (13%). Bridges cemented with Panavia showed the highest survival rate (67%) among the luting cements analysed for 5 years. Retentive tooth preparation, preparation confined to enamel, silicoating, supra gingival margins, Ni-Cr or Co-Cr alloys and no occlusion on pontic in lateral excursions have been reported to be associated with better survival rates. Anterior RBBs were found to be more retentive than posterior RBBs

121. Comparison of Metal-Ceramic and All-Ceramic Three-Unit Posterior Fixed Dental Prostheses: A 3-Year Randomized Clinical Trial. Nicolaisen et al, Int J Prosthodont ,  2016 May-Jun;29(3): 259-64 to compare the 3-year clinical outcome of metal-ceramic fixed dental prostheses (MC-FDPs) and zirconia all-ceramic fixed dental prostheses (AC-FDPs) replacing a posterior tooth. AIM 34 patients with a missing posterior tooth were chosen to receive either a MC-FDP (n = 17) or an AC-FDP (n = 17). evaluated at baseline and yearly until 3 years after cementation survival rates for MC-FDPs and AC-FDPs were 100%. success rate was 76% and 71% for MC-FDPs and AC-FDPs, respectively. 3 technical complications were observed in the MC-FDP group and 5 in the AC-FDP group, all chipping fractures of the ceramic veneer . 1biologic complication in the MC-FDP group (an apical lesion) was observed RESULTS

122. REFERENCES : A.E . Kahn, Partial Versus Full Coverage. J. Prosthet . Dent. 10:167-178, 1960 Johnstons , Modern Practice in Fixed Prosthodontics 4th edition 1986. T.Shillinburg.Fundamentals of Fixed Prosthodontics, III edition T.Shillinburg.Fundamentals of Fixed Prosthodontics, IV edition Rosenstiel , Land, Fujimoto. ContemperoryFixed Prosthodontics, III edition

123. Balasubramaniam et al , Predictability of resin bonded bridges – a systematic review. Br Dent J, 2017 Jun 9;222(11): 849-858. Shah et al, The Use of All-Ceramic Resin-Bonded Bridges in the Anterior Aesthetic Zone . Dent Update, 2017 Mar;44(3):230-2, 235-8. Raquel et al, All-ceramic inlay-retained fixed dental prostheses for replacing posterior missing teeth: A systematic review. J Prosthodont Res, 2018 Jan;62(1): 10-23. Karl M et al, Outcome of bonded vs all-ceramic and metal- ceramic fixed prostheses for single tooth replacement . Eur J Oral Implantol , 2016;9 Suppl 1:S25-44.