Fixed Partial Denture - Gingival Retraction

1. Good Morning

2. Gingival
Retraction in
Fixed Partial
Dentures
Presented by : Dr Harshil Modi (3rd Year Post Graduate )
Guided By : Dr Darshana Shah
Dr. Chirag Chauhan
Dr. Paras Doshi
Beyond the finish lines !

3. Index
 Definition
 Introduction
 Criteria for selection of retraction Cords
 Mechanical method
• rubber dam
• cotton twills with ZnoE cement
• copper band impression
• temporary acrylic resin copings

4. Chemical Method
• Chemical Agents
•Classification Of Retractin Cords & Indications
• Types Of Retraction Methods used
Electro surgery
•History
•Mechanism of Action
•Types of current
•Advantages and disadvantages
•Technique

5.  Recent Advances in Gingival Retraction material
• Muracel retraction strips
• Magic foam
• Expaysyl retraction paste
 Summary
 References

6. Definition
Gingival Retraction /Gingival Displacement:
The deflection of the marginal gingiva
away from a tooth
- GPT 9

7. GINGIVA

8. Fluids of Oral Cavity
Sign of warning in
examination when
examiner asks you wether
GCF is a Transudate or an
Exudate ?

9. Introduction
One of the important factor which contribute to the
success of cast restorations is marginal integrity.
Inadequate marginal fit leads to:-
-dissolution of luting agent.
-seepage and cervical caries.
-periodontal disease.
Though supra-gingival finish lines are preferred because
of their easy cleaning, finishing, impression making and
evaluation advantages, at times we have to make sub-
gingival finish lines.

10. Introduction
To achieve good marginal fit and esthetics the gingival
finish line should be recorded in the impression.
The inability of most final impression materials to
adequately displace soft tissues, fluid or debris mandates
adequate gingival displacement.

11. Aims Of Gingival Retraction
To reflect the gingiva and produce enlarged gingival sulcus both in vertical and lateral directions.
It also facilitates to refine the finish lines prior to impression making especially in anterior metal
ceramic restorations.
To obtain an adequate access to the prepared tooth to expose all necessary surfaces, both
prepared and not prepared.
To control seepage of gingival fluid.

12. Classification of gingival retraction methods
Mechanical Chemico – Mechanical
Rotary Gingival Curretage Electro Surgery
Classification

13. Mechanical Methods (Physical Compression)
1. Copper Band Impressions
Means of carrying the impression material and a mechanism for gingival retraction.
Technique
Selection of copper band.
One surface of band may be perforated.
Cervical end of the band may be trimmed in accordance with
the finish line.
The band is filled with soft wax and seated on the tooth.
The wax is chilled and impression is removed.
The impression indicates over extension of the band.
Adjustments if required may be made and second trial impression is
made.

14. Mechanical Methods

15. Mechanical Methods
The wax is melted and modelling compound is
introduced.
Seat the band securely into its position.
Pressure is applied on the compound directly.
Chill the impression.
A towel clamp may be used to remove the impression.
A NEW METHOD ADVOCATES USE OF
ELASTOMERIC MATERIALS AS WELL
Reference : Hovestad JF. Fixed Dental Prosthesis. St. Louis : Mosby , 1924: 34-36

16. Mechanical Methods
Can we evaluate the Disadvantages by ourselves ?
Hints :
Ruel, J., Schuessler, P.J., Malament, K. and Mori, D., 1980. Effect of retraction procedures on the periodontium in humans. Journal of
Prosthetic Dentistry, 44(5), pp.508-515.

17. Mechanical Methods
2. Rubber Dam
Heavy and extra heavy rubber dams were used.
Retraction is done by rubber dam or clamps (No. 212
cervical retainer).
Produced retraction by compression .
Advantages
 control of seepage and hemorrhage.
 ease of application.
Disadvantages
 full arch models cannot be made.
 severe cervical extension preparations.
 Cannot be used with polyvinylsiloxane impression
materials .

18. Mechanical Methods
Why Can VPS Impression
material not be used along with
this method ?
Basset, R.W., Ingraham, R. and Koser, J.R., 1964. An atlas of cast gold procedures (Vol. 2). Department of Operative
Dentistry, University of Southern California, School of Dentistry.

19. Mechanical Methods
3. Cotton Twills with ZnOe Cement
Employs gentle pressure over a period of time.
ZnoE mixed into creamy consistency.
Prevents sticking of pack to the instruments and
gives ease in handling.
Should reflect the tissue laterally.
Pack held in place with fast setting Znoe cement.

20. Chemico – Mechanical ( Retraction Cord )
Gingival retraction using chemically impregnated retraction cord is a mechanico-
chemical method of displacement .
Mechanical aspect involves placement of the cord into the gingival sulcus.
Chemical aspect involves effect of the chemicals/medicaments in the cord on the gingival
sulcus.

21. Chemico – Mechanical ( Retraction Cord )
Benson, B.W., Bomberg, T.J., Hatch, R.A. and Hoffman, W., 1986. Tissue displacement methods in fixed prosthodontics. Journal of
Prosthetic Dentistry, 55(2), pp.175-181.

22. Trade Name: Prevest DenPro Haemostal Liquid

23. Chemico – Mechanical ( Retraction Cord )
Mechanism of Action
A) Vasoconstrictors – Physiologically restrict the blood supply to the area by decreasing the size of
the blood capillaries, tissue fluid seepage and consequently size of the free gingiva. Ex:
epinephrine and norepinephrine
B) Biologic fluid coagulants: Coagulate blood and tissue fluids locally, creating surface layer that is
efficient sealant against blood and crevicular fluid seepage. Ex: 100% alum, 15-25% aluminium-
chloride, 10% aluminium potassium sulphate and 15-25% tannic acid.
C) Surface layer tissue coagulants – coagulates surface layer and free gingival epithelium as well as
seeped fluids, this creating temporarily impermeable film for underlying fluids.
Disadvantage: Ulceration, local necrosis, and change in the dimension and location of the free
gingiva.
Ex: 8% zinc chloride and silver nitrate.

24. Chemico – Mechanical ( Retraction Cord )
Review of Literature ( Agents no longer used )
8% Racemic Epinephrine ( used and popuar only till late 1980’s)
45% Negatol solution(45% condensation product of meta cresol sulfonic acid and
formaldehyde)
Caustic acid –sulfonic acid ,trichloracetic acid.
Nasal and ophthalmic decongestants-
 Oxymetazoline hydrochloride 0.05%
 Tetrahydrozoline hydrochloride 0.05%
 Phenylephrine hydrochloride 0.25%
Combinations of chemicals
Cocaine 10% with 0.1% epinephrine
Zinc chloride with 8% epinephrine

25. Chemico – Mechanical ( Retraction Cord )
8% Racemic Epinephrine ( used and popuar only till late
1980’s)
™Is 1 Of 2 Hormones Of Sympathetic Part Of AUTONOMIC
NERVOUS SYSTEM ™Able & Crawford (1897) - Separated
Epinephrine From Medullary Portion Of Adrenal Gland ™Acts As
A Vasocostrictor
Primary Site Of Action On Walls Of Small Arterioles. LOCAL
EFFECT Produces Hemostasis Local Vasoconstriction
Transitory Gingival Shrinkage
There Is No Benefit In Increasing The Strength Of Epinephrine Impregnated Cord
Beyond 4% For Hemorrhage Control (Timberlake)

26. Chemico – Mechanical ( Retraction Cord )
FACTORS AFFECTING AMOUNT OF EPINEPHRINE ABSORPTION
1) Degree Of Exposure Of Vascular Bed (Gogerty et al)
2) Time Of Contact (Woychesin)
3) Amount Of Medication In Cord (Forsyth et al)
4) Amount Of Laceration Of Gingival Tissue
5) No Of Teeth Prepared
6) Epinephrine In L.A. ( If Used)
7) Endogenous Secretions
8) Medications Taken ( If Any)

27. Chemico – Mechanical ( Retraction Cord )
EPINEPHRINE SYNDROME
1)tachycardia
2) Increased Blood Pressure
3) Nervousness
4) Anxiety
5) Increased Respiration
6) Post Operative Depression
These Effects May Appear After Cord Has Been In Place For A Few Mins/Some Time After
Removal Of Cord

28. Article Criticizing use of Racemic Epinephrine
Banu, S. and Jain, A.R., 2018. Evaluation of variation in the systemic blood pressure among Indian population after placement of
retraction cord with and without local anesthesia containing epinephrine. Drug Invention Today, 10(1).

29. Viva Voice
Which Chemical Agent ( commonly ) do we use in Gingival Retraction ? ( in our department )
What is the concentration of the chemical agent we use ?
What is the time that should be kept in ?
What is Monsels Solution ( 25 % Fe2 so4 )

30. Chemico – Mechanical ( Retraction Cord )
 A gingival retraction cord is the one which is having a tapered diameter throughout its
length and having a length sufficient to enable the cord to be wrapped several times
about a tooth. In use, the cord, starting with its smaller end, is spirally wrapped and
packed about a tooth between the tooth and surrounding gingival tissue to form a flared
gingival crevice.
 Patent number: 4465462
Filing date: Apr 27, 1983
Issue date: Aug 14, 1984
Inventor: Verne E. Ticknor
 Current U.S. Classification
433/136; 433/215; 132/93; 604/1
 International Classification
A61C 514

31. Chemico – Mechanical ( Retraction Cord )
Desirable qualities of a cord ( Donovan, Gandara, Nemetz)
 Dark Color To Maximize Contrast With Tissues,Tooth & Cor d
 Absorbent To Allow For Uptake Of Wet Medicament
 Available In Different Diameters To Accommodate
Varying Morphologies Of Gingival Sulcus Cord May Be Saturated With Solution
 Prior To Insertion
 Placed Dry, Solution Applied
 Previously Impregnated By Manufacturer

32. Chemico – Mechanical ( Retraction Cord )
Classification of Retraction Cords
a. Depending on the configuration
Braided
Twisted
Knitted
b. Depending on surface finish
waxed
unwaxed
c. Depending on the chemical treatment
plain
impregnated

33. Chemico – Mechanical ( Retraction Cord )
Classification of Retraction Cords
d. Depending on number strands
single
double-string
e. Depending on the thickness
black 000
yellow 00
purple 0
blue 1
green 2
red 3

34. Knitted gingival retraction cord Dan E. Fischer
 . Because of the presence of numerous interlocking loops, the knitted retraction cord is
longitudinally elastic, thereby avoiding the tendency to become dislodged once packed
as additional portions of the cord are packed around the margin of a tooth. The knitted
retraction cord is also transversely resilient, thereby tending to better conform to the
gingival sulcus.
 Patent number: 4522593
Filing date: Jul 7, 1983
Issue date: Jun 11, 1985
Inventor: Dan E. Fischer
 Current U.S. Classification
433/136
 International Classification
A61C 514

35. Braided gingival retraction cord Don D. Porteous
A gingival tissue retraction cord is provided which comprises a
suitably dimensioned, moderately firm, flexible, multistrand,
braided, absorbent cord impregnated with an effective amount
of gingival tissue retraction material.
.
Patent number: 4321038
Filing date: Jul 18, 1980
Issue date: Mar 23, 1982
Inventor: Don D. Porteous
Assignee: Van R Dental Products, Inc.
Primary Examiner: John J. Wilson
Current U.S. Classification
433/136; 128/335.5
International Classification
A61C 514

36. Teflon-coated intraoral tissue retraction
cord Jeffrey O. Earle
The retraction cord (or tape) includes a thermoplastic material such as polytetrafluoroethylene
(i.e. PTFE or Teflon) so that the cord is resistant to shredding, tearing, and sticking to dental
restorative and impression taking materials.
Additionally, chemical treatment of the cord may be avoided so as to reduce the risk of harmful
side effects in chemically sensitive patients.

37. Chemico – Mechanical ( Retraction Cord )
Indications of #000
Anterior teeth
Double packing
Substitute for black silk suture as lower cord in the "two-cord" technique
Indications of #00
Preparing and cementing veneers
Restorative procedures dealing with thin, friable tissues

38. Chemico – Mechanical ( Retraction Cord )
Indications of #0
Lower anteriors
When luting near gingival and subgingival veneers
Class III, IV and V restorations
Second cord for "two-cord" technique
Indications of #1
Tissue control and/or displacement when soaked in coagulative hemostatic solution prior to and/or
after crown preparations
Protective "pre-preparation" cord on anteriors

39. Chemico – Mechanical ( Retraction Cord )
Indications of #2
Upper cord for "two-cord" technique
Tissue control and/or displacement when soaked in coagulative hemostatic solution prior to and/or
after crown preparations
Protective "pre-preparation" cord on anteriors
Indications of #3
Areas that have fairly thick gingival tissues where a significant amount of force is required
Upper cord for those desiring the "two-cord" technique

40. Gingival Biotype
Does Gingival
Biotype effect
the type of
retraction cord
used ?

41. Gingival Biotype

43. Chemico – Mechanical ( Retraction Cord )
ARMAMENTARIUM
1) Evacuator (saliva ejector, svedopter)
2) Scissors
3) Cotton pliers
4) Mouth mirror
5) Explorer
6) Fischer Ultra Packer (small)
7) DE plastic filling instrument IPPA
8) Cotton rolls
9) Retraction cord
10) Hemodent liquid
11)Dappen dish
12) 2 x 2 gauze sponges

44. Chemico – Mechanical ( Retraction Cord )
Requirements of Instrument used for placing cord
1) Double Ended With Adequate Blade Angle & Offset To Allow All Areas Around A Full Crown
Preparation To Be Packed
2) Blade Should Be Long Enough To Reach Deep Finish Lines
3) Small Enough In All Dimensions To Avoid Gingival Injury During Cord Placement
4) End Of Blade Should Be Flat
5) No Sharp Corners Should Be Present

45. Chemico – Mechanical ( Retraction Cord )
45 degrees to handle. most popular packers; heads at 45
degrees to the handle with three packing sides. Circular
packing of the prep is completed without the need to flip
the instrument end for end. Use the small packer on lower
anteriors and upper lateral incisors.
90 degrees & parallel to handle. Same size and three
sided heads as our 45 degrees packers, except one of
the heads is in line with the shank and the other is at a
right angle to the shank.

46. An Alternative….

47. Chemico – Mechanical ( Retraction Cord )
Techniques of gingival retraction:
Single cord technique.
Double cord technique.
Infusion technique of gingival displacement.
Every other tooth technique.

48. Chemico – Mechanical ( Retraction Cord )

49. Chemico – Mechanical ( Retraction Cord )

50. Chemico – Mechanical ( Retraction Cord )

51. Chemico – Mechanical ( Retraction Cord )
Double cord technique:
Indication:
When making impression of multiple prepared teeth and when making
impression when tissue health is compromised.
Procedure: Small diameter cord is placed in sulcus. This cord is left in
the sulcus during impression making.
Second cord is soaked hemostatic agent of choice is placed in the
sulcus above small diameter cord.
After waiting 8-10 minutes, the larger cord is removed.

52. Video for Double Cord Technique

53. Chemico – Mechanical ( Retraction Cord )
Infusion technique:
It is indicated to control the haemorrhage.
Infuser is used with a burnishing motion in the
sulcus and carried circumferentially 360°
around the sulcus.
Haemostasis is verified, a knitted retraction
cord is soaked in ferric sulphate and packed
into the sulcus.
The cord is removed after 1-3 minutes.

54. Chemico – Mechanical ( Retraction Cord )

55. Chemico – Mechanical ( Retraction Cord )
A study on new series of knitted and twined gingival cord impregnated with 8% epinephrine and
25% aluminium sulphate and concluded that knitted gingival cords were better than twined cords
and cords containing epinephrine performed clinically no better than aluminium sulphate cords.
Jokstad, A., 1999. Clinical trial of gingival retraction cords. Journal of Prosthetic Dentistry, 81(3), pp.258-261.

56. Chemico – Mechanical ( Retraction Cord )
Ferenc Csempesz et al in 2003
conducted a study to determine the
optimum soaking time for 3 retraction
cords of different thickness to ensure
adequate uptake of the hemostatic
solution and concluded that 20 mins of
soaking time was necessary for
saturation of the cords before use.
In addition to soaking time, the saturation
of the cord with solution largely depends
on wetting of the cords.
Csempesz, F., Vág, J. and Fazekas, Á., 2003. In vitro kinetic study of absorbency of retraction cords. Journal of Prosthetic
Dentistry, 89(1), pp.45-49.

57. Rotary Gingival Curretage
“Gingitage” or “Denttage”
Troughing technique
Purpose is limited removal of epithelial tissue while a chamfer finish line is being created.
Amsterdam gave the concept,further developed by Hansing and Ingraham.

58. Rotary Gingival Curretage
Criteria for rotary curettage
1.Must be done on healthy and inflammation free tissue to prevent tissue shrinkage that occurs
when diseased tissue heals.
2.Absence of bleeding on probing.
3.Sulcus depth less than 3.0 mm.
4.Presence of adequate keratinized gingiva.

59. Rotary Gingival Curretage
Technique
Shoulder finish line preparation at gingival crest using flat end tapered diamond.
Then with a torpedo diamond finish line is extended apically,1/2 to 2/3 the depth of the
sulcus.
Place aluminium chloride impregnated retraction cord to control hemorrhage.
Remove the cord after 4-8 minutes and make impression.

60. Rotary Gingival Curretage

61. Rotary Gingival Curretage
Violation with Basic Biological Prinicple of tooth
preparation ?

62. Electro Surgery / Electro Cautery
Often “electrocautery” is used to describe
electrosurgery.
This is incorrect. Electrocautery refers to direct
current (electrons flowing in one direction) whereas
electrosurgery uses alternating current.
During electrocautery, current does not enter the
patient’s body. Only the heated wire comes in
contact with tissue.
In electrosurgery, the patient is included in the
circuit and current enters the patient’s body.

63. An Electro Cautery Unit

64. Electro Surgery / Electro Cautery
Fun Fact
History
Schillinburg stated that the use of heat as surgical tool was known to Egyptians about
3000BC.
Experiments of d’Arsonvol (1891) demonstrated that electricity at high frequency will pass
through a body without producing a shock (pain or muscle spasm), instead producing an
increase in the internal temperature of the tissue.
This discovery was used as the basis for eventual development of electrosurgery.

65. Electro Surgery / Electro Cautery
Mechanism Of Action
Controlled tissue destruction.
Current flows through a small cutting electrode.
Producing high current density and rapid temperature rise .
Cells directly adjacent to the electrode are destroyed due to this temperature increase.

66. Electro Surgery / Electro Cautery
Tissue Considerations
Keep electrode in motion.
Appropriate current setting.
Larger the electrode ,greater the current required.
5-10 seconds between applications.
Tissue must be moist.
Electrode must remain free of tissue fragments.
Electrode must not touch any metallic restorations.

67. Electro Surgery / Electro Cautery
Advantages
Clear operating area without or no bleeding.
Healing by primary intension.
Lack of pressure to incise tissue.
Electroplaining of tissue.
less tissue loss after healing

68. Electro Surgery / Electro Cautery
Disadvantages
Unpleasant odour.
Slight loss of crestal bone (Kamansky F.W. et al)
Burn mark on the root surface.
Not suitable for thin gingiva.

69. Whilelmsen et al
Whilelmsen et al reported:
1. cemental destruction with subsequent impaired cementogenesis
2.lack of epithelial and connective tissue reattachment
3.significant recession of free gingival margin
4.Apical positioning of sulcular epithelium
5.Slight loss of crestal alveolar bone
6.Burn marks on the root surfaces where the electrode contacted

70. Technique
Anesthesia
A drop of aromatic smelling oil.
Complete seating of electrodes in handpiece.
Light pressure and quick ,deft stokes.
7mm per second
5-10 seconds between each stroke.
Power selector dial ,as recommended.

71. Healing after electrosurgery
Wounds by fully rectified filtered current in a
healthy gingiva of adult males showed epithelial
bridging at 48 hours and complete clinical healing
at 72hrs
However as stated by Malone and Kelly
(DCNA 1982;26(4);851 ) the use of ORINGER’S
SOLUTION……………enhanced healing to 3 to 5
days
Kalkwarf, K.L., Krejci, R.F. and Wentz, F.M., 1981. Healing of electrosurgical incisions in gingiva: early histologic observations in
adult men. The Journal of prosthetic dentistry, 46(6), pp.662-672.

72. Recent Advances
In 1978, Van der Velden and De Vries studied the
forces applied to the sulcus during various dental
procedures. They observed a tearing of the
epithelial attachment as soon as pressure of
1N/mm2 was applied to the marginal gingiva. This
attachment was destroyed when the pressure
exceeded 2.5N/mm2.
Al Shayeb, K.N., Turner, W. and Gillam, D.G., 2014. Accuracy and reproducibility of probe forces during simulated periodontal pocket
depth measurements. The Saudi dental journal, 26(2), pp.50-55.
Expasyl retraction paste

73. Recent Advances
• The pressure applied by a retraction cord in this region is between 5 and 10N/mm2
(depending on the number of cords inserted into the sulcus). A simple periodontal probe
exerts a pressure between 1 and 2N/mm2. To separate the marginal gingiva from the
human tooth at a distance of 1.5 mm, it is necessary to apply a pressure of 0.1N/mm2.
• The conclusion of these studies was that gingival retraction should be accomplished
under a pressure of between 0.1 and 1N/mm2 to avoid tearing of the epithelial
attachment.
Velden, U. and Vries, J.H., 1978. Introduction of a new periodontal probe: the pressure probe. Journal of Clinical Periodontology, 5(3),
pp.188-197.

75. Recent Advances
 COMPOSITION
 1) Kaolin 66.75%
 2) Water 23.36%
 3) AlCl3 6.54%
 4) Colorant 1.02%
 5) Essential oil of lemon 0.33%

76. Expasyl

77. Recent Advances
Magic Foam
Magic FoamCord is a new non-hemostatic gingival
retraction system by Coltène/Whaledent. Magic FoamCord
is reportedly the first expanding vinyl polysiloxane material
designed for retraction of the gingival sulcus without the
potentially traumatic and time-consuming packing of
retraction cord. Magic FoamCord material is syringed
around the crown preparation margins and a cap
(Comprecap) is placed to reportedly maintain pressure.
After five minutes, the cap and foam are removed and the
tooth is ready for the final impression.

79. Recent Advances

80. Recent Advances
Gingi Trac
GingiTrac is a medium-viscosity, vinyl polysiloxane (VPS) gingival retraction paste with 15%
ammonium aluminum sulfate (alum) that gently displaces the gingiva from the tooth and
stops bleeding.
When used with GingiCap™ compression caps, the mechanical bite pressure of GingiCap
combined with the astringent action of aluminum sulfate works to control bleeding and
seepage in just minutes.
GingiTrac cleans up easily and completely, without tissue trauma.

81. Recent Advances
Marco Ferrari et al in 1996 they
found merocel a synthetic
material that is specifically
chemically extracted by a
biocompatible polymer
(hydroxylate polyvinyl acetate)
Merocel

82. 3M™ ESPE™ Astringent Retraction Paste

83. Meta Analysis of Cord Vs Cordless Technique

84. References
1.Donovan T.E. et al: Review and survey of medicaments used with gingival retraction
cords. J.P.D.1985 vol.58 pg.525-531
2.Miller I.F:Fixed dental prostheses. J.P.D.1958 vol.8 pg.483-495
3.Ruel J. et al:Effects of retraction procedure on periodontium of humans. J.P.D.1980 vol.44
pg.508-514
4.Reiman B.Milford:Exposure of subgingival margins by non-surgical gingival displacement.
J.P.D.1976 vol.436 pg.649-654.

85. References
 5.Barkmier WW ,Williams H.W.:Surgical methods of gingival retraction for restorative
dentistry. J.A.D.A. 1978,vol.96,pg.1002-1007
 6.Benson D.W et al:Tissue displacement methods in fixed prosthodontics.
 J.P.D.1986,vol.55,pg.175-182
 7.La Forgia A:Cordless tissue retraction for fixed prostheses J.P.D.1967,vol.17,pg.379
 8.Buchanan W.T,Thayer K.E.:Systemic effeccts of epinephrine-impregnated retraction
cords in fixed partial denture prosthodontics. J.A.D.A. 1982,vol.104,pg.482
 9.Zeena Raja,Chandrashekharan Nair A clinical study on gingival retraction. A survey
on the use of gingival retraction cords by dental professional. JIPS 2003,vol.3 pg.21,30

86. References
 10.W.D.Mello,V.Chitre et al:Gingival retraction cords-their role in tissue displacement:A
Review JIPS2003,vol.3,pg.16
 11.Charbeneau G.T. et al Operative Dentistry,Philadelphia 1966.Lea and febiger
 12.Gillmore H.W. et al Operative Dentistry,4th edi.st.Louis 1982.C.v.mosby co.
 13.Flocker J.E:Electrosurgical management of soft tissue and restorative dentistry. DCNA
1980 vol24 pg 247.
 14.Jonston J.F,Phillips R.W. modern practice in crown and bridge prosthodontics.4th edi.
Philadelphia,Saunders co.
 15.Shillingburg H.T etal. Fundamentals of fixed Prosthodontics.3r edi.quintessence
pub.co

87. References
16.Rosenstiel,Land,Fugimoto - Contemporary Fixed Prosthodontics 3rd edi. The mosby co.
17. Marco Ferrari et al 1996, JPD 75; 242-7.
18. Asbjorn Jokstad, JPD 1999, 81; 258-61.
19. Ferenc Csempesz et az, JPD 2003; 89: 45-9.
19. Charles J. Goodaru, JPD 1990; 64: 1-12.
20. Klug G. Richard, JPD 1966; 16: 955-961.
21. Azzi et al, JPD 1983; 50: 561
22. William H. Liebenberg, JADA 1993; 124: 92-102.

88. References
 Land,Rosenstiel and Sandrik JPD july 1994:72(1);4-7
 Ronald D Woody and Amp Miller JPD aug 1993:70(2);191-192
 DCNA 1982,26(4);759-780
 www.ultradent.com
 www.valleylab.com
 Haemostatic agents used in periradicular surgery: an experimental study of their efficacy
and tissue reactions by: T. von Arx, S. S. Jensen, S. Hänni, R. K. Schenk (2006);
International Endodontic Journal Volume 39 Issue 10 Page 800 - October 2006
 Expa syl a unique clinical technique;JADA 2003 nov,134(11);1485