This document discusses various materials that have been used for retrograde root canal fillings. It begins by outlining the ideal properties of retrograde filling materials, including good adhesion, biocompatibility, and preventing microorganism leakage. The document then examines the properties and limitations of numerous materials that have been used, including amalgam, zinc oxide-eugenol cements, glass ionomer cement, MTA cement, and various other alternatives. It provides details on the composition, sealing ability, biocompatibility and other characteristics of each material. In conclusion, the document states that MTA cement is currently considered the best material due to its biocompatibility, sealing ability and dimensional stability.

2. 2
RETROGRADE FILLING
MATERIALS
Dr. Deepesh Mehta
(Batch 2018-21)

3. Contents
 Introduction
 Ideal Requirements
 Retrograde Filling Materials
 Conclusion
 References
3

4. Introduction
 Resection of the root end during periradicular surgery results in
an exposed apical dentine surface bounded by cementum with a
root canal at its centre. Following the apical preparation, a
retrograde filling material is usually used to seal the root-end
cavity.
 Apicoectomy followed by retrograde filling is a well-
established procedure to treat teeth with persistent periapical
infections and teeth in which conventional root canal therapy
has failed. 4

5.  The main purpose of placement of a root end filling material is
to provide an adequate apical seal.
 The most important objective of filling the root end
preparation is to hermetically seal it from bacteria or
byproducts.
5

6. Ideal Properties
 Sticks and adapts to the walls of the preparation.
 Easy to use.
 Dimensionally stable.
 Moisture-resistant.
 Insoluble in tissue fluids.
 Nonstaining.
6

7.  Prevents leakage of micro-organisms and their products to the
peri radicular tissues.
 Bactericidal or bacteriostatic.
 Biocompatible and cementogenesis promotor.
 Radiopaque.
7

8. Materials
 Amalgam
 Zinc Oxide-eugenol (ZOE) Cements
 Intermediate Restorative Material (IRM)
 SuperEBA
 Glass lonomer Cement (GIC)
 Diaket
 Gold Foil
 Gutta-percha 8

9.  MTA (Mineral Trioxide Aggregate)
 Composite
 Compomers
 Bioceramics
9

10. Amalgam
 Amalgam has been used for a long time, but it has several
problems.
 There tends to be marginal adaptation and filtration. There is
also a problem with biocompatibility.
 Amalgams with a higher content of copper or zinc were also
cytotoxic due to ion release.
 In addition, a galvanic current is produced due to contact with
metal posts and crowns.
10

11.  Finally, tattoos arise due to corrosion of amalgam/silver cones or
leaving amalgam outside the cavity or removal of previous
apicoectomies with amalgam/old silver cones.
 Amalgam studies show that success rates were as low as 44%,
especially in studies longer than 5 years.
11

12. ZincOxide-eugenol(ZOE)Cements
 Zinc oxide-eugenol cements have been used in the past decade
to replace amalgams; but they contain eugenol which, in contact
with tissue fluids, is hydrolyzed and released.
 When ZOE comes in contact with water, it undergoes surface
hydrolysis, producing zinc hydroxide and eugenol. This reaction
continues until all the ZOE in contact with the free water is
converted to zinc hydroxide.
12

13.  Free eugenol has several dangerous effects depending on its
concentration and length of exposure.
 It depresses vasoconstrictor response, and suppresses or
enhances effects on the immune response. It can be an allergen
and eliminates native oral microorganisms.
 It depresses vasoconstrictor response, and suppresses or
enhances effects on the immune response. It can be an allergen
and eliminates native oral microorganisms.
13

14.  Other materials have been added to the basic ZOE mixture in an
effort to increase the strength and radiopacity and reduce the
solubility of the final material.
 Commercially available ZOE materials include intermediate
restorative material (IRM; Dentsply Caulk, Milford, DE) and
Super-EBA (Bosworth Company, Skokie, IL).
14

15. Intermediate Restorative Material (IRM)
 Intermediate Restorative Material is a modified ZOE cement that
has been reinforced by the addition of polymethacrylate in the
powder, eliminating the absorbability problem and eliciting a
milder reaction.
 IRM consists of a powder containing greater than 75% zinc oxide
and approximately 20% polymethacrylate mixed in equal parts
with a liquid that contains greater than 99% eugenol and less than
1% acetic acid.
15

16.  Studies show a better biocompatibility and higher clinical
success rate than amalgam.
 IRM appears to be tolerated in the periradicular tissue, but it has
no dental hard-tissue regenerative capacity.
 In a tissue tolerance study, it was found that IRM elicited little
to no inflammatory effects after 90 days, which led to the
conclusion that the oral tissue was just as tolerant of IRM as it
was of any other retrograde filling material.
16

17. SuperEBA
 Super ethoxybenzoic acid cement is an improved IRM.
 Super-EBA consists of a powder containing 60% zinc oxide,
34% aluminum oxide, and 6% natural resins. It is mixed in equal
parts with a liquid that contains 37.5% eugenol and 62.5% ortho-
ethoxybenzoic acid.
 Ethoxybenzoic acid was developed in an attempt to alter the
setting time and increase the strength of basic ZOE cements.
 Super EBA is pH neutral, has low solubility, and has less
leakage than amalgam. 17

18.  It produces minimal chronic inflammation in the apex.
 SuperEBA adapts very well to canal walls compared with
amalgam, which appears to be well condensed but has poor
adaptation.
 However, it is a difficult cement to manage when a large cavity
has to be sealed, because of its short setting time, and it is also
greatly affected by moisture and disintegrates in acidic pH.
18

19.  In summary, superEBA cement is well tolerated by tissues, is
fast setting, polishable and dimensionally stable, and provides a
good apical seal.
 Disadvantages are that is difficult to manage, sensitive to
temperature, moisture and acidic pH, and is only moderately
radiopaque.
 It has no capacity to regenerate cementum.
19

20.  For application, the liquid and powder are mixed in a 1:4 ratio.
The powder is mixed into the liquid slowly in small increments.
Once the rolled SuperEBA mixture loses its shine and the tip
does not droop when picked up by a carrier, the mixture has the
right consistency.
20

21. Glass lonomerCement (GIC)
 Glass ionomer cement consists of aqueous polymeric acid, such
as polyacrylic acid, plus basic glass powders, such as calcium
aluminosilicate.
 The cement can be either light or chemically cured.
 GIC is very technique-sensitive however, there are the benefits of
biocompatibility and GIC is adhesive to dentine.
21

22.  As with IRM, it is greatly affected by moisture and blood during
the initial setting time, resulting in increased solubility and
decreased bond strength; this significantly occurred in
unsuccesful cases.
 The cytotoxicity and tissue response is similar to ZOE-based
cements
 The tissue response to GIC is considerably more favorable than
to amalgam and similar to that with ZOE-based materials
22

23. Diaket
 Diaket (ESPE GmbH, Seefeld, Germany) a polyvinyl resin
initially intended for use as a root canal sealer, has been
advocated for use as a root-end filling material.
 It is a powder consisting of approximately 98% zinc oxide and
2% bismuth phosphate mixed with a liquid consisting of 2.2-
dihydroxy-5.5 dichlorodiphenylmethane,
propionylacetophenone, triethanolamine, caproic acid
copolymers of vinyl acetate, and vinyl chloride vinyl
isobutylether.
23

24.  Leakage studies comparing Diaket to other commonly used root-
end filling materials have shown it to have a superior sealing
ability.
 When Diaket was used as a root canal sealer, biocompatibility
studies showed that it was cytotoxic in cell culture276 and
generated long-term chronic inflammation in osseous502 and
subcutaneous tissues.
 However, when mixed at the thicker consistency advocated for
use as a root-end filling material, Diaket has shown good
biocompatibility with osseous tissues.
24

25. Gold Foil
 The use of gold foil as a root-end filling material was first
reported in 1913 and 1920.
 It exhibits perfect marginal adaptability, surface smoothness and
tissue biocompatibility.
 Implants of gold foil produce only mild tissue reaction.
 Gold Foil was found to be the best apical sealing material as far
as the improvement in biting force is concerned.
25

26.  When compared to IRM, composite resin, amalgam and glass
ionomer, goldfoil was least toxic.
 The routine use of gold foil as a root-end filling material does not
appear practical because it requires a moisture free environment,
careful placement and finishing.
26

27. Gutta-percha
 Gutta-percha cones or pellets contain approximately 19–22%
gutta-percha, 59–75% zinc oxide, and a series of other additives
including waxes, colouring agents, antioxidants and metallic
salts.
 Most of the earlier treatment failures with this material were
related to poor adaptation of gutta-percha to the canal walls.
 Leakage can be seen in many surgical cases without using
methylene blue.
27

28.  Gutta-percha cones have shown evidence of toxicity in very
sensitive tests in vitro. This is thought to be due to the high zinc
oxide content.
 Therefore, the surgeon cannot rely on cold- or heat-burnished
gutta-percha and finish microsurgery after apicoectomy without
preparing a 3 mm deep apical microcavity and obturating it with
a well-sealing and dimensionally stable biocompatible cement.
28

29. MTACement
 MTA consists of tricalcium silicate, tricalcium aluminate,
tricalcium oxide, and silicate oxide. It also has bismuth oxide
powder for radiopacity.
 The crystals are composed of calcium oxide and the amorphous
matrix is composed of 33% calcium, 49% phosphate, 2% carbon,
3% chloride, and 6% silica.
 Calcium and phosphorous are the main ions. Iron is absent in the
white MTA.
29

30.  Hydration of the powder, which has a mean particle diameter of
10 nanometers, produces a colloidal gel that solidifies into a hard
structure consisting of discrete crystals in an amorphous matrix.
 The compressive strength is quite low at 24 hours (40 MPa) but
it increases to 67 MPa at 21 days after mixing.
 The solubility of MTA is similar to amalgam and superEBA.
Importantly, it is hydrophilic, so moisture and blood do not
affect its setting.
30

31.  Initially the pH is 10.2, but this increases to 12.5 at 3 hours after
mixing. Its radiopacity (7.17) is reasonable, being higher than
superEBA and IRM.
 It is currently the only available filling material that produces a
cementum deposition layer over it, and only a minimal degree of
inflammatory cell response, periodontal ligament regeneration
thickness and osseous healing.
31

32.  MTA is the best filling material available today in terms of
biocompatibility, sealing ability, dimensional stability.
 Disadvantages are that, although moisture is required for its
setting, during packing, isolation is critical because just one drop
of liquid can remove it from the retrocavity.
 Also, its setting time is very long, radiopacity is not high, and
clinically is the least scientifically tested cement, so far.
32

33. Composite Resin
 It should be used in cases when apicoectomy or retrocavity or
both cannot be made due to:
1. Cast posts that fill the canal all the way down.
2. Previous apicoectomy that has resected the root up to the level
of the post.
3. Weak dentin walls remaining after apicoectomy that cannot
support ultrasonic vibration, or short roots where apicoectomy
will make the roots even shorter
33

34. 4. Composite leaks less than superEBA, IRM and GIC.
 However, it is a material that is more sensitive to technique
because moisture and blood contamination during the
bonding/setting process reduces bond strength and increases
leakage.
34

35. Compomers
 Geristore (Dent-Mat, Santa Maria, CA, USA) is a resin-
reinforced glass ionomer hybrid in a dual-curing paste/paste
formulation of a hydrophilic bisphenol-A-glycidyl methacrylate
(bis-GMA) with long-term fluoride release.
 It is less sensitive to moisture than conventional glass-ionomer
cement, but a dry environment produces stronger bonds.
35

36.  These materials have been shown to be equal or superior to IRM
and equivalent to superEBA in their ability to reduce apical
leakage.
 In Europe a composite resin-type material named Retroplast
(Retroplast Trading, Dybersovej, Denmark) was introduced in
endodontic surgery with favorable long-term results.
 The root end management with these materials (Geristore and
Retroplast) is different from that in endodontic microsurgery
36

37.  The major disadvantage of these resin-type materials is
difficulty in avoiding blood/moisture contamination.
37

38. Newer Materials>>
38

39. Bioceramics
 Bioceramics are a relatively new and potentially promising
addition to the group of materials available for root-end filling.
 In vitro testing of EndoSequence Root Repair Material (ERRM;
Brasseler, Savannah, GA) demonstrates biocompatibility and
antimicrobial activity that is similar to MTA.
 ERRM is composed of calcium silicates, monobasic calcium
phosphate, and zirconium oxide.
39

40.  The material is hydrophilic, radiopaque, and has high pH.
ERRM is available as a putty and a syringable paste.
 An advantage of RRM, based on clinical experience, is its
handling properties, similar to that of Cavit (3M, St. Paul, MN
USA).
 RRM is biocompatible, hydrophilic, insoluble, dimensionally
stable, a high PH, has 30 minutes of working time, and as short
as 2 hours setting time.
40

41. Bioaggregate
 Bioaggregate is a modification of MTA.
 It is a new bioceramic root repair and root-end filling material
composed of a powder component consisting of tricalcium
silicate, dicalcium silicate, tantalum pentoxide, calcium
phosphate monobasic and amorphous silicon oxide and a liquid
component of deionized water.
41

42.  In a study investigating the cytotoxicity of Bioaggregate,
Bioaggregate showed a significantly better inflammatory
reaction and foreign body reaction than the MTA.
 An in vitro comparative study of the sealing ability of Diadent
Bioaggregate and other root-end filling materials was done using
methylene blue dye penetration technique; the results showed
that microleakage was significantly less in Bioaggregate.
42

43. Biodentine
 It is a calcium silicate based material introduced in 2010 and is
used as a material for crown and root dentin repair treatment,
repair of perforations, apexifications, resorption repair and root-
end fillings.
 The main component is a highly purified tricalcium silicate
powder that contains small amounts of dicalcium silicate,
calcium carbonate, and a radioopaquer.
 The flowable consistency of Biodentine penetrates dentinal
tubules and helps in the mechanical properties of the interface.
43

44.  Investigation of the bioactivity of Biodentine, MTA and a new
Tricalcium silicate cement revealed that all three cements
allowed the deposition of hydroxyapatite on the surface. This
shows that all three materials are bioactive.
 An in vitro study to compare the sealing ability of MTA and
Biodentine; MTA showed the highest seal and the least dye
absorbance. Biodentine showed a seal slightly less than MTA.
44

45. Ceramicrete
 This material has hydroxyapatite powder and cerium oxide
radioopaque fillers.
 It is a self-setting phosphate ceramic that sets using an acid-base
reaction to form a potassium magnesium phosphate hexahydrate
ceramic matrix phase.
 A comparison of the root-end seal achieved using ceramicrete,
bioaggregate and White MTA was done to study the prevention of
glucose penetration; Both bioaggregate and ceramicrete showed similar
sealing ability to MTA, with ceramicrete showing significantly better
results than bioaggregate. 45

46. iRoot BPplus
 iRoot BP Plus (Innovative BioCeramix Inc., Canada) is a
synthetic water-based bioceramic cement. It is available in
ready to use premixed form and has a biocompatibility similar
to MTA.
46

47. GenerexA
 Generex A (Dentsply Tulsa dental, USA) is a calcium silicate
based cement and is similar to MTA but the handling properties
are different.
 Instead of water the cement is mixed with a special gel.
 The final consistency is similar to IRM like dough and easy to
manipulate.
47

48. Endobinder
 EndoBinder (Binderware, Brazil) is a new calcium aluminate
cement.
 During production, free magnesium oxide and calcium oxide are
eliminated to avoid expansion of the material and ferric oxide
which can cause tooth discolouration is also eliminated.
48

49. Conclusion
 Many different materials have been advocated for use as root
end filling materials, and each has specific advantages and
disadvantages.
 However, from the biologic perspective of regeneration of the
periradicular tissues, MTA, followed by Retroplast, appears to
have a clear advantage over the other available materials.
49

50.  Bioceramic materials may join this group, but require more
clinical testing.
 Retroplast and other composite resin–based filling materials
require meticulous hemostasis and a dry surgical field for
optimum results.
 The most commonly cited disadvantage of MTA is its handling
properties.
 Even when properly prepared, MTA is more difficult to place in
the root-end cavity than most other materials.
50

51.  No ideal retrofilling cement exists. IRM has been substituted by
superEBA, but it continues to be the cement of choice in large
cavities like strip perforations.
 SuperEBA is a reinforced IRM cement that provides a good
apical seal. MTA is today's gold standard, and it is even easier
and faster to work with than superEBA.
 Amalgam is no longer used.
51

52. References
 Cohen’s Pathways of the Pulp: 11th Edition.
 Endodontic Microsurgery: Merino.
 Ingles Endodontics: 6th Edition.
 Microsurgery in Endodontics: Syngcuk Kim.
 Kanchan Bhagat., et al; “Root End Filling Materials and Recent Advances: A
Review”; EC Dental Science 12.2 (2017): 46-57.
 J. Aqrabawi; Sealing ability of amalgam, super EBA cement, and MTA when
used as retrograde filling materials; BRITISH DENTAL JOURNAL, 188(5).
 Emre Bodrumlu; Biocompatibility of retrograde root filling materials: A
review; Aust Endod J 2008; 34: 30–35.
52