root canal sealers1 / orthodontic courses by indian dental academy
TRANSCRIPT
ROOT CANAL SEALERS
In endodontic practice, the success of root canal therapy mainly
depend on achieving a compact fluid tight seal of the apical end of the root
canal, so as to prevent the ingress and accumulation of irritants causing
biological breakdown of attachment apparatus leading to failure. root canal
sealers along with solid core material plays a major role in achieving the
fluid tight seal.
The sealers are binding agents used to adapt the rigid gutta percha to
canal walls and to fill up the voids, accessory canals and irrigularities
within the canal. Several types of root canal sealers are used in endodontic
practice with each one having own merits and demerits.
Brief history:
1. In 1931 – The original zinc oxide eugenol cement was developed as a
root canal sealers by Rickert.
2. 1936, Grossman’s non-staining ZOE formula appeared as a sealer that
afforded more working time.
3. In 1952 Biocalex, a calcium oxide based sealer was introduced by
Bernord.
4. In 1955 – Scheufele introduced resin based Diaket as a sealer.
1
5. In 1960 Wichterle and Lin introduced a plastic material Hydron.
6. In 1961, Tubliseal was introduced with a slight modification to Ricket’s
formula.
7. In 1965, Nyborg and Tullin gave a formula of Kloropercha.
8. In 1973, N2 a relatively recent formula by Sargnti was introduced for
root canal sealing purpose.
9. In 1976, Ailford recommended endodontic glass iononmer ketac-endo
as a root canal sealers.
Function of sealers
1) Binding agents – They form a band between filling and the dentinal
walls.
2) Antimicrobial Agents – It should have contain germicidal action.
3) As a filler – When used to fill the discrepancies between the bone and
the canal walls.
4) As a lubricant. It is for lubrication when used in conjunction with solid
care material like guttapercha.
2
5) Radioopacity – is a property rather than a furcation which disclose the
presence of auxiliary canals, resparative areas, root fixtures and the
shape of the apical foramen.
Ideal Requirements
1. Should provide an excellent seal apically and laterally.
2. Should provide adequate adhesion when set.
3. Should be radioopaque.
4. Should be non-staining.
5. Should be diamentionally stable.
6. Should be easily mixed adequate working time and introduced into the
canal.
7. Should be easily removed if necessary.
8. Should be insoluble in tissue fluid.
9. Should have bacteriocidal or bacteriostatic action.
10. Should be non irritant to periapical tissue.
11. Should be absorbable when extruded into periapical regim.
12. Film thickness should be minim possible.
13. Should not be cytotoxic.
14. Should not be cariogenic.
3
Classified
I. Based on their composition (Messing color Atlas)
a. Eugenol based.
i. Silver containing.
ii. Silver free.
b. Non eugenol based.
c. Medilated.
Silver containing are – e.g., Kerr Sealer, Procosol, (disadvantage
was staining of the teeth).
Silver free – We have E.g.:
- Procosol non staining.
- Grossman’s sealer.
- Tubliseal.
- Wach’s paste.
II. Non eugenol sealers
a. Diaket (resin based).
b. AH-26 (Resin based).
c. Khorperk and Eucaperch.
4
d. Nogenol, Hydron endofil. GIC, Calcium phosphate, Cyanoacrylates and
polycarboxylates.
III. Medicated (These include group of sealers that have therapeutic
properties) E.g:
- N2 Endomethasone.
- SPAD.
- Idoform paste, Diaket, Riebler’s paste.
- CA(OH2) paste.
- Mynol cement.
According to Grossman
1. Zinc oxide cement
2. Calcium hydroxide cement.
3. Paraformal dehyde cement.
4. Pastes.
According to Cohen
Type I – Class I, Class II.
Type II – Class I, Class II, Class III.
Type III – Class I, Class II, Class III and Class IV.
5
Type I
Class I – Metallic.
Class II – Polymeric
Type II
Class I - Powder and liquid non polymerizing.
Class II – Pastes and non polymerizing.
Class III – Polymer resin system
Type III
Class I - Powder and liquid non polymerizing.
Class II – Pastes and non polymerizing.
Class III – Metal amalgam.
Class IV – Polymers.
According to Clark
- Absorbable.
- Non-absorbable.
According to Ingle:
- Cements
- Paste.
- Pontics.
6
According to Harty:
1.Zinc oxide eugenol based
- Tubliseal
- Wach’s paste.
- Grossman.
2. Resin based.
- AH-26.
- Diaket.
- Hydron.
3. G.P. based
- Chloropercha.
- Eucapercha.
4. Dentin Adhesive materials
- GIC.
- Cyanoacrylate.
- CaO2
- PO2
- Composite material.
- Polycarboxylate.
7
5. Medicated cements
- Paraformaldehyde – calcium hydroxide.
- Calcibiofic (CRCS).
- Sealapex.
- Bicalex.
Nicholus (alphabetical order).
Eugenol based
I(a) Silver containing cements.
1. Kerr root canal sealer (Ricket’s formula).
Composition:
Zinc oxide 41.2%.
Precipitated silver 25-30%
Resins 16-30%
Tynol iodide 11-12%
Liquid
Eugenol 70-80%
Canada balsam 20-22%
8
One drop of liquid is added to one packet of powder and mixed with
heavy spatula. Because of presence of precipitated sealing the granular
appearance remain when the spatulation is completed.
This sealer completely sets and is inert within 15-30 minutes, thus
reducing inflammatory response.
Kerr RCS are mainly recommended for warm G.P. technique where
lateral canals are present.
Advantage:
1. Excellent lubricating properties.
2. Working time is 30 minutes when mixed in 1: 1 ratio.
3. Germicidal action.
4. Biocompatible.
5. Because of granular structure greater bulk thus file voids, space and
auxiliary canals.
6. Prostogladin inhibition (zinc eugenol)
Disadvantage – presence of silver makes it extremely staining.
2) Procosal – again it is a silver containing cement.
Powder Liquid
Zinc oxide 45%
PPt silver 17%
Hydrogenerated resin 36%
MgO 2%
Eugenol 90%
Canada balsam 10%
9
- This cement in granular in nature and fills and void and auxiliary
canals.
- Extremely staining cement.
Silver Free Eugenol Containing RCS
1) Procosol
Powder Liquid
Zinc oxide 40%
Stayblite resin 27%
Bismuth subcarbonate 15%
Barium sulphate 15%
Eugenol 80%
Oil of almond 20%
Grossmans cement
Most advocated cement because of:
- Good sealing ability.
- Stratifies most requirements.
Powder Liquid
Zinc oxide 40%
Stayblite resin 30%
Bismuth subcarbonate 15%
Barium sulphate 15%
Sodium bicarbonate amyhyrous 1
Eugenol 5 parts
Manipulation
10
Mixed as sterile scale with spatulas, 2 to 3 drops of liquid is used
and powder is added in increments and mixed to a smooth creamy
consistency.
Cement hardens at approximately 2 hours at 37°C but in root canal
it begins to set with 10-30 minutes (because of moisture present in the
dentin).
The desirable properties of Grossman cement are:
1. Its slow setting time.
2. Plasticity.
3. This property is due to pressure of sodium bicarbonate amyhydrous.
Also it has good sealing potential, volumetric change upon setting is
very small.
Disadvantage
- Coarse resin particles may lodge on the canal wall preventing the root
canal filling from setting at cement level.
11
2) Tubliseal
It is a two paste system: 1) Bare, 2) Catalyst.
Base paste Catalyst
1. Zinc oxide 57-59%
2. Olco resin 18-21%
3. Bismuth thioxide 75%
4. Thymol Iodide 3.75%-5%
5. Oil and waxes 10%
6. Barium sulphate
Eugenol polymerized resin
- Setting time is mixing pad is 20 minutes.
- In root canal it is 5 minutes.
Wach’s Sealer (1955)
Composition:
Powder Liquid
Zinc oxide 19gm
Tricalcium phosphate 2gms
Bismuth subcarbonate 3.5gms
Barium sulphate 0.3 gms
Heavy MgO 0.5gms
Eugenol 6 ml
Canada balsam 20 ml
- Medium or good working time.
- Minimum lubricating quality.
- Periapical irritation is minimal.
12
- Possess germicidal action.
- Stages in position because of tactiness at the tip because of Canada
Balsam.
Disadvantage – Storage odour of the liquid.
To summarize:
1. Basically ZOE based one easy to manipulate.
2. Ample working time.
3. Adhesion is good because of limited dimensional changes.
4. Germicidal.
5. Radiopaque.
6. Minimal staining except for silver containing cements like Kerr and
Procosol.
The probable disadvantages are:
- Irritant to periapex and not easily absorbed from apical tissue.
Now for the setting reaction in brief:
Zinc oxide eugenol sets because of a combination of physical and
chemical reaction yielding to a hardened mass of zinc oxide embedded in a
matrix of long sheath like crystals of zinc eugenolate.
The presence of moisture, particle size, pH and additives are
important factors affecting the setting reaction.
13
Tissue culture studies showed ZOE formulations to be cytotoxic.
The inflammation in the periapical region has shown to persist for
years until excess eugenol or ZOE cement absorbed or phagocytored by
macrographs.
II. Non eugenol sealers
1. Kloroperka Sealer : (P/L system)
Powder Liquid
Canada balsam 19%
Rosin 11.8%G.P. 19.6%
Zinc oxide 49%
Chloroform
The powder is mixed with liquid chloroform, after insertion the
chloroform evaporates having voids, it has been shown to be associated
with greater degree of leakage than any other sealers.
Because chloroform is a Kran Carcinogen.
Eucupercha was used
G.P. is dissolved in eucalyptol, which can be used either as sealer in
combination with G.P. cone or as cone filling materials. However it
exhibits, considerable shrinkage after setting.
14
AH-26
It is a epoxy resin based sealer recommended by Shroeder in 1954.
Powder Liquid
Bismuth oxide 60%
Hexamethylene tetramine 25%
Silver powder 10%
Titanium oxide 5%
Bisphenol diglycidyl ether
The formation has been modified by eliminating silver powder to
prevent discolouration.
It has a very slow setting time.
36-48 hours at body temperature.
5-7 days at room temperature.
Advantages
- Is that good sealing ability.
- Possess antibacterial action.
- Low toxicity.
- Well tolerated by periapical tissue.
Disadvantages
- It contracts slightly while setting.
15
- Parasthesia may access following the use AH-26, but recovery may
occur with 1-2 years.
- It inhibits leucocyte migration.
Diaket
It is a polyvinyl resin reinforced zinc oxide sealer chelates is formed
to zinc oxide and a small amount of pontic dissolved in liquid B-
diaketome.
Manipulation
- 2 drops of liquid is mixed with the scoop of powder and mixed to a
thick consistency.
- Changing the powder, liquid ration affects the hardness of the final set
and radioopacity.
Advantages:
- Also diaket is superior to other sealer in tensile strength and resistance
to permeability.
Disadvantages
- Setting time – 6-8 minutes on room temperature and even more rapid in
the root canal.
- Mild inflammatory reaction when diaket is overfilled. Diaket is known
(or its resistance to absorption).
16
Diaket A
Chemically diaket A is similar to diaket and also contain the
disinfection “Hexachlorophene”. Diaket is one of the few medicated
cement which does not contain paraformaldehyde.
Hydron
It is a rapid setting hydrophillic, plastic material used as a root canal
sealer without the use of core or other words. Hydron is a polymer and
hydroxyethyl methacrylate (HEMA).
It is available as an injectable root canal filling material.
Working time is 6 to 8 minutes.
The syringe method makes it difficult to control the placement of
practice gel accurately. It is concluded to be biocompatible material that
conform to the shape of the canal also when in comes in contact with
moisture, the gel absorbs water and swells.
Endofill
Injectable silicon resin sealer which can be used in conjugation with
core material or as a sole filling material to be injected in to canal space
with pressure syringe.
It consists of silicon monomer and a silicon based catalyst plus
bismuth subnitrate as a radipacifier. The catalyst is tetra ethyl ortho silicate
polydimethyl.
17
The mixed silicon has low working viscosity with good adaptation
to tooth structure and good protraction of accessory canals, it cures to pink
rubbery solid resembling G.P.
Silicone material in general exhibit low toxicity and are that to
tissue.
Glass Ionomer cement
Ketac-Endo
- The use of GIC for endodontic use was recommended in early 1970,s
by Putford.
- GIC is the reaction produce of an unleachable glass powder and
polyacrylic acid in organic solutions. On setting they form hard poly
salt gel which adhere to enamel and dentin. GIC is saturated and injured
into the root canal.
18
Advantages
1. Good physical properties.
2. Good bonding to dentin.
3. Good flow properties.
4. Few voids.
5. Less cytotoxic
Disadvantages:
It cannot be removed in the even of re-treatment. However recent
studies shown that GIC can effectively removed by chloroform solvent
followed by 1 minute ultrasonic instrumentation.
Polycarboxylate cement:
Consists of modified zinc-oxide powder and an aqueous solution of
polyacrylic acid. The cement has chelating action bonding to both enamel
and dentin. Because of its adhesive property and antibacterial action of this
cement has be tested as root canal sealer. However apical seal is found to
be inferior to other materials. It exhibits an inflammatory response when
extruded into periapical tissue.
19
Cyanoacrylic Cements:
These are composite type polymers that can be polymerized to hard
products by the use of basic inorganic material that also serves as filled.
They have been reported to be bio-compatible but not in much use.
Medicated cement:
The medicated sealers consists of paraformaldehyde, iodoform,
calcium hydroxide or other powerful antiseptics. They fail to provide a
compact root canal filling, but prolonged therapeutic effect.
Riebler’s paste : Paraformaldehyde based.
Powder / Liquid formulations:
Powder :
Zinc oxide.
Formaldehyde
Barium sulphate.
Phenol.
Liquid:
Formaldehyde
Sulphuric acid.
Ammonia
20
Glycerine.
Mynol cement: Iodoform based
Powder:
Zinc oxide
Iodoform
Rosin
Bismuth Subnitrate
Liquid
Eugenol
Cresol
Thymol
These materials are used without core materials and are introduced
into root canal by lentulospiral or some type of infection device.
Paraformaldehyde containing paste exhibits severe inflammatory reaction
and tissue necrosis. Hence it is used as a sealer is restricted.
21
Paraformaldehyde
N2 : Was introduced by Sargenti and Ritcher in 1961. Two type of N2
sealers were available initially i.e.:
N2, Normally for root filling and
N2, Apical as antiseptic medication.
Recently N universal a cement containing the feature of both N2
normal and N2 apical has been developed for endodontic use.
Composition:
Powder:
Zinc oxide
Lead tetraoxide
Paraformaldehyde
Bismuth subcarbonate
Titanium dioxide
Bismuth subnitrate
Phenyl mercuric borate
68.51 gms
12 gms
4.70 gms-Antiseptic
2.60gms – Opacifier
8.40gms- Adhesion
3.70gms – Opacifier
0.05 gms - Antiseptic
Liquid:
Eugenol
22
Oleum Roae
Olum Lavandulae
Corticosteroids are now added separately as hydrocortisone powder.
Severe irritation is its major drawback of N2. Increased blood lead level
absorbed after N2 insertion.
Endometasone : Powder / Liquid
Powder:
Zinc oxide
Bismuth subnitrate
Dexamethasone
Thymol iodide
Paraformaldehyde
100gms
100gms
0.019gms
25 gms
2.20gms
Liquid
Eugenol
The powder is pink coloured and mixed with eugenol to thick
consistency. It exhibits severe irritation and masks the inflammatory
reaction. Therefore sometimes gives rise to pain after 6 to 8 hours of
insertion.
23
Spad :
This material is advertised as a one visit non-irritant, radiopaque
filler and sealer. It is a resorbinol formaldehyde resin supplied as a powder
and 2 liquid.
Powder :
Zinc oxide 72.9gms
Barium sulphate
Titanium dioxide
Paraformaldehyde
Hydrocortizone acetate
Calcium hydroxide
Phenyl mercuric borate
Liquid L : (Clear liquid)
Formaldehyde 87.00 gms
Glygerin 13.00gms
24
Liquid LD : (Red colour)
Glycerine 55gms
Resorcinol 25 gms
Hydrochloric acid 20 gms
Equal parts of the 2 liquids are mixed with powder. The essential
reaction to form the resin is between the resorcinol and the formaldehyde.
To take place this reaction and pH is essential which is provided by Hcl.
The role of zinc oxide is to control the pH and to prolong the setting time.
The setting time of SPAD is 24 hours, during which small quantities of
formaldehyde gas is released.
Indications:
1. Pulpotomies in both deciduous and permanent teeth.
2. For the treatment of acute endodontic infections.
3. Teeth with periapical infections.
When SPAD is used in the treatment of periapical infection, a small
amount is intentionally introduced beyond the apex with the belief that the
sterilizing effect helps healing.
25
Calcium Hydroxide has been used in endodontics as a root canal
filling material, in intracanal medicament or as a sealant in conjugation
with solid core materials. Pure Ca(OH)2 can be used or can be mixed with
saline solution, methylecellulose or anesthetic solution. However pH of all
these mixtures has found to be between 12.5 to 14.5.
The use of Ca(OH)2 paste, as a root canal filling material is based
on the assumption that, there is formation of hard structure or tissue at the
apical foramen. Ca(OH)2 neutralizes the acids produced by bacteria and
thereby decreasing the osteoclastic activity. The activity of Ca(OH)2
stimulates the induction of alkaline phosphate thus forming the hard tissue.
Ca(OH)2 sealers may contain soley of Ca(OH)2 or it is combined
with zinc oxide. E.g., Sealapex, Apexit, CRCS. Procalex. Life Sealer 26.
Sealapex:
Is a product of Kerr manufacturing company has been described as
non eugenol Ca(OH)2 polymer resin root canal sealer.
Composition : It is a 2 paste formulation.
Base paste:
Zno with Ca(OH)2
Butyl Benzine.
26
Sulfonamide
Zinc Stearite and sumicron silica.
Catalyst
Barium sulphate
Titanium dioxide
Isobutyl salysilate
Acrocil R 972
Two pastes are dispensed equally on mixing pad and mixed to a
smooth, uniform consistency. It never sets on dry atmosphere which makes
the presence of moisture essential for setting of sealapex. In 100% it takes
3 weeks to reach a final set. Sealapex expands while setting. It is
biocompatible and shows good osteogenic potential.
CRCS (Calcibiotic Root Canal Sealers):
It is the first sealer of the Ca(OH)2 group. It is basically a zinc oxide
eugenol eucolyptol sealer to which Ca(OH)2 has been added for its
osteogenic effect.
Composition : Powder / Liquid system).
27
Powder :
Zinc oxide
Hydrogenated Rosin.
Barium sulphate
Calcium hydroxide
Bismuth subcarbonate
Liquid L :
Eugenol
Eucalyptol
CRCS is mixed like any other powder-liquid sealers. It sets both in
dry as well as wet conditions. It shows very negligible water sorption,
hence more stable, when compared to sealapex and other resin based
sealers.
Biocalex : Is another Ca(OH)2 based sealer consists of :
Powder:
Calcium hydroxide
Zinc oxide
28
Liquid :
Glycol
Water
Powder and liquid when mixed to form a paste acts as both
intracanal medicament and as a sealer. After placement in the prepared
cavity, it expands to more than 6 times is original volume, penetrating into
all parts of root canal system.
Iodoform pastes :
Is a resorbable paste used alone or in combination with other core
materials. It consists of:
1. 60 parts of iodoform.
2. 40 parts of solution of Parachlorophenol
3. 49% Camphor (antiseptic solution).
4. 6% menthol (antiseptic solution).
Iodoform paste is intentionally placed beyond the apex to stimulate
the inflammatory reaction, the end result of which is repair. It also
accelerates the bone formation. The paste in periapical region is removed
by phagocytic action and slowly disappears with time.
29
The disadvantage of iodoform paste is that it induces severe
inflammatory reaction and with time discoloration, the tooth if not
removed from the pulp chambers. The introduction of iodoform paste into
the root canal may lead to rise in the iodine level in blood, hence
contraindicated in patients who are sensitivity to iodine.
Newer sealers:
1. Endofloss.
2. Appetite Root canal sealer.
3. Root canal sealers containing Tetra-calcium – Dicalcium phosphate
and 1% chondrotin sulphate.
Endofloss:
Endofloss is a sealer consisting of powder liquid formulation.
Powder:
Zinc oxide.
Iodoform
Calcium hydroxide.
Barium sulphate.
30
Liquid:
Eugenol
Parachlorophenol
It is a zinc oxide based medicated cement. Mixing is similar to that
of procosol (zinc oxide sealer). Setting time is approximately 30-45
minutes. Relatively biocompatible. It also a absorbable sealer.
It induces severe inflammatory reaction in 48 hours and gradually
reduced after 3 months. Cytotoxicity was observed along with coagulation
necrosis which is attributed in the presence of iodoform parachlorophenol.
Appetite root canal sealer
One of the recently introduced sealers.
Powder and Liquid Combination
Powder:
-tricalcium phosphate.
Hydroxyl apatite
Iodoform
Bismuth subcarbonate
31
Liquid:
Polyacrylic acid.
Distilled water.
3 types – Type I, Type II and Type III
1) Type I : AR used for vital pulpectomy. Type II –30% iodoform used
in infected canals that has radiopacity, bactericide and bone invigoration effects.
Type III – in between cases which contains a 5% of iodoform. It can be also used in the
treatment of accident perforation, as a retrograde filling material.
Advantages Disadvantages
1. Biocompatible Sets quickly, hence multiple mix essential.
2. Osteogenic potential Low radiopacity
3. Low tissue toxicity Low wetting ability.
Newly Developed Calcium Phosphate type Sealers are:
a. Tetracalcium phospate (TeCP)
b. Dicalcium Phosphate Dihydrate (DCPD).
c. A modified McIIvain’s and Buffer solution (TDM).
d. TDM-S-Buffer solution + 2.5% Chondroitin sulphate.
32
Composition : Powder and liquid systems
TDM-S TDM
Powder
Tetracalcium phosphate
Dibasic Calcium phosphate
Liquid
Citric acid
Dibasic sodium phosphate
Chondroitin sulphate.
Distilled water
Tetracalicum phosphate
Diabasic calcium phosphate
Citric acid
Diabasic sodium phosphate
Chondroitin sulphate
Distilled water
Studies have shown excellent biocompatibility.
No periapical inflammatory reaction seen.
Chondrotin and other ingredients said to promote wound healing.
Application of a Root canal sealer
RCS may be placed in the canals either by lentulospirals or by
Reamers and files. Lentulospiral is made up of fine wire spiraled into the
shape of a reverse spiral. It can be used by finger or attached to hand piece.
When spiral turned clockwise it carries cement apically. It should not be
33
used in narrow canal for the reason that if binds result in breakage. It tend
to push cement outside the canal when used with handpiece and may set
too rapidly as a result of its whipping action.
Whatever may be the means of application it should be coated
uniformly along the canal walls (Coating the mater cone and accessory
cones with sealers is recommended as it reduces the voids and irregularities
within the canals.
34