5. COURTHOUSE BUILT
OF LIME STONE
KANSAS, USA
USES:
BUILDINGS
FLOCCULANT
DENTISTRY
GREEN HOUSE EFFECT
PETROLEUM REFINING
5
6. History In Dentistry
1920 -Hermann introduced calcium hydroxide as a pulp
capping agent.
1930 - Calcium hydroxide became frequently used in the
vital pulp therapies.
1939 -Before the second World War an European immigrant
Zander introduced dentists in USA to its use.
1941 -The first literature regarding the successful healing
using calcium Hydroxide appeared.
1959 -The use of calcium hydroxide for apical closure was
first reported by Granath.
6
7. 1966 - Frank popularized the use of calcium hydroxide for
the apical closure.
1975 -Maisto classified the calcium hydroxide paste as an
alkaline paste because of its high pH.
1976 - Cvek successfully used calcium hydroxide for
induction of hard tissue in the apical portions of the root
canal, especially of immature teeth with infected pulp.
1983 -Garcia considered calcium hydroxide as the best
medicament to induce hard tissue deposition and promote
healing of vital pulpal and periapical tissues.
7
8. Properties
Calcium hydroxide is white odorless powder with the
formula Ca(OH)2.
Molecular weight of 74.08.
It has low solubility in water which decreases as the
temperature rises.
Has a high pH(about 12.5 to 12.8).
Insoluble in alcohol
Chemically classified as a strong alkaline base
8
12. Dental formulation of calcium hydroxide.
SETTING-used for the lining or sub-lining of
cavities, or as root canal sealers.
NON-SETTING- dressing root canals.
Setting materials - Therapeutic effect-
pH
Levels of unbound calcium and hydroxyl ions
12
13. Setting mechanisms of calcium-hydroxide
containing materials.
There are two basic setting mechanisms.
(i) The two-paste system, which is based on the
reaction between calcium and zinc ions and a
salicylate chelating agent, and is accelerated by
the presence of water (Lim & McCabe 1982).
13
14. The single-paste system, which utilizes the
polymerization of a dimethacrylate by means of
light. A potential disadvantage of the
dimethacrylate systems, when used as a base
beneath composite restorations, is their
adherence to the composite material and
subsequent withdrawal from the base of the
cavity during polymerization (Papadakou 1989).
14
15. Non-setting calcium hydroxide materials
Material Vehicle
Analar CaOH water
Pulpdent Methyl cellulose
Hypo-cal Methyl cellulose
Reogan Methyl cellulose
15
16. Aqueous
Water
Saline
Dental anaesthetics with or without vasoconstrictors
Ringer’s solution
Aqueous suspension of Methylcellulose or
Carboxymethyl cellulose
Anionic detergent solution.
Eg: Tempcanal , Calyxyl, Pulpdent.
16
17. CLINICAL IMPORTANCE:
Ca 2+ and OH- are rapidly released.
High degree of solubility when the paste remains in
direct contact with the tissue and the tissue fluids
causing it to be rapidly solubilized and resorbed by
the macrophages.
The root canal must be redressed several times until
the desired effect is achieved there by increasing
the number of appointments.
17
19. OILY
Olive oil
Silicone oil
Camphor(the essential oil of camphorated
parachlorophenol)
Metacresylacetate
Some fatty acids such as oleic linoleic isostearic
acids.
Eg: Endoapex.
19
20. MECHANISM OF ANTIMICROBIAL ACTIVITY :
pH
Hydroxyl ion
DAMAGE TO THE BACTERIAL CYTOPLASMIC MEMBRANE :
Hydroxyl ion lipid peroxidation phospholipid
hydrogen ion
unsaturated fatty acids free lipidic radical
+ oxygen
Autocatalytic chain lipidic peroxide
radical
Complete destruction ( Cotran et al 1999 )
20
21. PROTEIN DENATURATION : ( Voet 1995)
ionic bond
↑ PH Tertiary structure of protein
# covalent structure
#polypeptide chain variable
irregular spatial
conformation
X biologic activity
X cellular metabolism
21
22. Calcium Hydroxide Induced Mineralization
Only in direct contact.
Calcium hydroxide is an initiator rather than a
substrate for repair.
Rise in pH as a result of free hydroxyl ions may
initiate the process.
Local buffer against acidic reactions
Alkaline pH also neutralizes the lactic acid
secreted by osteoclasts.
22
23. BIOMECHANICAL ACTIONS
Initiation of mineralization
Initiators
Vit D dep protein
Phosphoproteins
phospholipids
Inhibitors
Pyrophosphate ions
23
24. Material exerts a mitogenic and osteogenic
effect.
High pH activates alkaline phosphatase activity.
Heithersay suggested that calcium ions may
reduce the permeability of new capillaries , so
that less intercellular serum is produced thus
increasing the concentration of calcium ions at
the mineralization site.
24
25. MECHANISM OF REMINERALIZATION
Calcium Hydroxide
Reduced capillary Neutralizes acid produced by
permeability osteoclasts
Reduced serum flow Optimum pH for
pyrophosphatase activity
Reduced levels of inhibitory levels of ca2+ dependent
Pyrophosphate pyrophosphatase
Uncontrolled mineralization
ca OH−
25
26. Dentine bridge
A mineralized barrier or 'dentine bridge' is
usually produced following the application of
calcium hydroxide to a vital pulp (pulpotomy).
This repair material appears to be the product
of odontoblasts and connective tissue cells. The
barrier may not always be complete (Holland et
al. 1979).
26
27. Dentine bridge formation varies depending on
the pH of the material.
High pH- Pulpdent
Low pH- Dycal.
Can be radiographically differentiated.
27
28. Antibacterial effect of setting calcium
hydroxide materials (Fisher & Shortall
1984)
Strong effect -Dycal (original formula) Reocap*
Procal
Medium effect -Dycal (new formula) Life
Renew,Reolit*
No effect – WPC, Hydrex, Cal-Mer
28
29. Healing with CH
Zone of obliteration (early changes; caustic
effect: area of superficial debris)- 1 hour.
Zone of coagulation necrosis (Schroder’s layer
of ‘firm necrosis,” Stanley’s “mummified zone”).
The line of demarcation.
Dense zone- connective tissue fibers in 2-3
days, extensive collagen formation- 3-7 days.
15 days- UMC into preodontoblasts and
columnar shaped odontoblasts.
29
30. Calcification of bridge: 2 weeks- appearance of
predentine.
1 month - coronal layer of irregular osteodentin-like
tissue with cellular inclusions, and the pulpal part
consists of predentin lined with odontoblasts.
3 months -definitely two layered, consisting
coronally of dentin like tissue with irregular tubuli
and cellular inclusions; the tissue nearest the vital
pulp exhibits predentin, densely packed collagen
fibrils, and tubules with cellular extensions
(Tomes’ fibers) indicative of a higher level of
differentiation.
30
31. Dissolution of necrotic material
First reported by Hasselgren in 1988.
The coagulated necrotic tissue above the line
of demarcation degenerates completely and
collapses. When the tooth is reopened and the
CH layer is removed, the clinician’s instrument
drops into a chamber or a pit (“the coffin”), the
bottom of which is the top of the calcified
dentinal bridge. Pulpdent and CH and water.
31
33. Liner
They are applied in thickness of 25 micrometers
Functions of a liner are minimizing marginal leakage,
neutralizing acids and occluding (closing) the
exposed dentinal tubules for pulp protection.
33
34. Advantages:
○ Rapid initial set - accelerating effect of
moisture in the ambient air of the oral cavity
and from within the dentinal tubules.
○ Do not interfere with the setting reaction of
Bis-GMA resins- composite resin materials.
○ Initial set in thin sections - sufficiently hard to
resist the applied condensation pressures that
are required for restoration ( even for amalgam
alloys- Lim and Mcabe 1982)
34
35. Base
Functions
Thermal insulation and to supplement mechanical
support for the restoration by distributing local
stresses from the restoration across the underlying
dentinal surface.
An additional function is closing the dentinal
tubules - preventing the leached chemicals from the
restorations irritating the pulp.
Thermal diffusivity of calcium hydroxide is low
35
37. Vital pulp capping
Vital pulp capping is the dressing of an exposed pulp
with the aim of maintaining pulp vitality .
vital pulp tissue -production of secondary dentin -dentin
moist - resilience and toughness --- protection
Emphasis has shifted from the "doomed organ"
concept of an exposed pulp to one of hope and
recovery -CH
37
38. A successful pulp cap has a vital pulp and a
dentin bridge within 75 to 90 days
Non-sterile procedures and bacterial micro-
infiltration of the pulp via dentinal tubules -
major causes of post-operative inflammation
and pulp necrosis .
38
39. Indirect pulp capping
Bactericidal property (king et al. 1965, Fisher
1972) which help to control (Fisher 1977) but
not entirely eliminate (Watts & Paterson 1987)
the few viable organisms that may remain.
39
40. Indirect Pulp Capping
After gross excavation,
the deepest layer of
carious dentine covered
with Calasept.
After 6 weeks the cement was
removed, Calasept washed away
and the excavation of the carious
dentin completed without pulp
exposure.
40
41. When the effective dentin (remaining dentine) thickness
is more than 100 micrometers, healthy reparative
reaction is likely to occur in the pulp. ( i.e. forming
reparative dentine and calcific barriers to be followed by
secondary dentine containing dentinal tubules formed by
odontoblasts.
When the effective dentin (remaining dentine) thickness
is less than 100 micrometers, healthy unreparative
reaction is likely to occur in the pulp.
•the degeneration of the odontoblasts occur,
• formation of dead tracts,
•cessation of secondary dentin formation
•reversible, mild pathological changes in the pulp
•differentiation of odontoblasts from undifferentiated
mesenchymal cells of the pulp and production of
reparative dentin.
41
42. Even with a vital pulp, indirect pulp capping with calcium
hydroxide is NOT DONE in Class V cavities in gingival
aspects of deep axial walls to prevent excess
calcification, strangulating the coronal pulp.
The rate of reparative dentin formations has been shown
to average 1.4 micrometer per day following cavity
preparation in dentin in human teeth.
The rate of formation decreases markedly after 48 days
(Stanley 1966).
For indirect pulp capping, non setting calcium hydroxides
provide higher availability of calcium and hydroxyl ions.
(Tamburic et al ).
42
43. The two problems - internal resorption and uncontrolled
calcification of the remaining pulp.
Calcium hydroxide pulpotomy in
a deciduous tooth is usually avoided
because of the tendency for
internal resorption to occur at the
junction between the remaining radicular pulp and
the calcium hydroxide.
The current view in initiation of resorption is the disruption
in predentin layer or precementum layer that offers natural
resistance against resorption.
43
44. Seltzer and Bender mention the osteogenic potential of
calcium hydroxide which is capable of completely
obliterating the pulp chamber and root canals.
The current view regarding uncontrolled calcifications
is that calcium hydroxide application should be
restricted to teeth with healthy pulp. If the pulp is
degenerating, application of calcium hydroxide can
alter the pulpal degeneration into calcific degeneration.
44
45. Apexification Agent:
• Apexification is a procedure attempted in non-vital tooth
with an immature apex.
• The interim calcium hydroxide root canal filling serves the
purpose of stimulation of the calcific barrier in the apical
root end against which gutta percha may be condensed.
• The apexification technique was first reported by Kaiser
and Granath and popularized by Frank in 1966.
• Continued root formation may be expected from the
surviving HERS
45
46. The alkaline pastes used are as follows;
a) Maisto Cappuro Paste: Calcium hydroxide and iodoform in
equal parts with distilled water or a solution of 5 % methyl
cellulose.
These pastes are rapidly resorbed in the periapical region. The
average time for resorption is 1 to 10 days for each square mm
of surface of over obturated material as seen in the radiograph.
b) Frank’s Paste: Calcium hydroxide and camphorated
parachlorphenol. produces a severe inflammatory reaction on
initial application. Apexification.
Frank also suggested that the camphorated parachlorphenol is
an assurance that the paste will remain in the area of
apexification for a longer time.
46
47. c) Leonardo’s Paste: Leonardo called this paste as ‘Ca(OH)2
No 9’
It contains Calcium hydroxide, barium sulphate, resin and
polyethylene glycol.
It is usually used as ;
As a dressing between cases of pulpectomy.
To protect the vital apical and periapical tissues in the
obturation of the root canals.
As a temporary obturation in cases of incomplete
apexification to induce mineralization and allow formation
of new cementum .
47
48. Apexification aims to induce apical closure of
the open root apex with a hard-tissue barrier,
against which a root filling can be compacted .
The frequency of change of CaOH can increase
the speed of barrier detection but does not
appear to affect the position
Change of dressing in 3 months interval.
Closure of apex- 6-24 months.
Dang N Quintessence Int. 1999
48
49. Medicament for Arresting Resorption:
A non perforated internal resorption- may not be possible
to remove the hyperplastic pulp tissue from the resorption
defect completely.
Extirpate the normal pulp near the unvinvolved apical
region, thereby cutting the vascularity to the hyperplastic
tissue.
Pack with calcium hydroxide which has the ability to
dissolve the pulp tissue.
49
50. Anderson et al compared the pulp solving ability of 2 %
stabilized sodium hypochlorite solution and a commercial
calcium hydroxide solution (Calasept).
Human pulp fragments weighing approximately 0.0065 g
were immersed in these solutions at 37 ˚C for 10 days.
Sodium hypochlorite was able to dissolve half the volume
of pulp tissue within 1 hour and the remaining tissue in
2.5 hours. Calcium hydroxide solution dissolved half the
volume of pulp tissue within 2 hours and it took 1 week
for the remaining tissues to dissolve.
These findings support the use of sodium hypochlorite
for canal preparation and calcium hydroxide as a canal
dressing, especially in internal resorption cases.
50
51. External resorption - the pulp tissue --- intentionally extirpated
Calcium hydroxide - packed into the root.
It is postulated that’ the calcium and hydroxyl ions traverse the dentinal tubules
and reach the external resorption sites to exert their therapeutic effect.’
Nerwich et al were able to demonstrate pH changes in the outer root dentin over
a period of 4 weeks following root canal dressings of calcium hydroxide.
Bacterial Lipopolysaccharides(LPS) postulated to play a role in the resorption
process
intra canal medicament kills bacteria
the lysed bacteria can liberate LPS
LPS pass onto the periapical region and cause
--------action of IL1 , TNF-alpha
Safayi and Nichols evaluated the effects of calcium hydroxide on bacterial LPS
and found calcium hydroxide was able to hydrolyse the lipid moiety of bacterial
LPS.
resorption
51
52. Bacterial Lipopolysaccharides(LPS) postulated
to play a role in the resorption process
Intra canal medicament kills bacteria
the lysed bacteria can liberate LPS
LPS pass onto the periapical region and
cause --------action of IL1 , TNF-alpha
Safayi and Nichols evaluated the effects of
calcium hydroxide on bacterial LPS and found
calcium hydroxide was able to hydrolyse the
lipid moiety of bacterial LPS.
52
53. Intra canal medicament
Behnen et al. (2001) demonstrated that Ca(OH)2
decreased the numbers of E. faecalis at all depths
within dentinal tubules up to 24 h and that less
viscous preparations of Ca(OH)2 were more
effective in the elimination of E. faecalis from
dentinal tubules than viscous preparations.
Using an agar diffusion method, Ballal et al. (2007)
found that 2% CHX gel was a more effective
medicament than Ca(OH)2 paste against E. faecalis.
53
54. Krithikadatta et al. (2007) reported that, as an
intracanal medicament, 2% CHX gel alone was
more effective against E. faecalis when
compared to Ca(OH)2.
Lee et al. (2008) concluded that a polymeric
CHX-controlled release device (PCRD) was
significantly more effective in reducing
intradentinal bacteria than Ca(OH)2
54
55. Calcium hydroxide based root canal sealers have been
introduced as an alternative to the conventional zinc-oxide
eugenol based sealers (sealapex, CRCS).
Mineralized repair - induced. ( Holland and De Souza 1985).
When the pattern of release of calcium and hydroxyl ions
from different sealers was investigated by Tagger et al in
1988 it was found that Sealapex released ions and
disintegrated more rapidly than CRCS.
It was also found that although the release of calcium ions
from CRCS was negligible, the material continued to alkalize
it environment, possibly due to free eugenol combining with
calcium ions as they were released.
Root canal Sealer
55
56. Ca(OH)2-ZOE. complete
biological closure by neoformed cementum.
H&E, 100X.
Ca(OH)2-Sealapex. There is a biological
closure of the main apical foramen.
H&E, 100X.
56
57. Biocalex
Biocalex (now marketed as Endocalex) is a variant of calcium
hydroxide in paste form.
The powder contains Calcium oxide.
It is mixed to a slurry with ethylene glycol, ethyl alcohol and
distilled water.
In 1967, Bernard introduced Biocalex 4 which required a mixing
technique to break up inter molecular cohesion of the particles of
calcium oxide in order to obtain expansion of about 200%- 280%.
57
58. This formula was modified in 1973 by Bernard,
Powder- calcium oxide 66% and zinc oxide 33%.
Liquid- consisted of distilled water 20% and ethylene
glycol 80%..
58
59. Bernard’s hypothesis that success is due to expansion
of calcium oxide and the accompanying ‘chemical
incineration’ plus subsequent obliteration of the whole
canal system with calcium carbonate and calcium
hydroxide. The hardened material is then destined to
remain as a root canal filling.
59
61. Calcium Oxide
Biocalex- Calcium Oxide, Zinc oxide, glycol/ water liquid.
((Endocal)
Volumetric expansion causing penetration of inaccesible canals.
Better than calcium hydroxide –control bacteria (Cavalleri et al
1990)
Fill within 1.5 mms from apex –volumetric expansion
Not radio-opaque
Only available in USA
and in Canada
61
68. J Dent Oral Med 2004, Vol 6 No 01
Treatment of intrabony defects with Alpha-TCP and an oily Calcium
Hydroxide suspension. A 14-case-report
Alpha-Tricalcium Phosphate + oily Calcium Hydroxide suspension
68
70. Base or a liner?
Sometimes referred to as a base but only
should be used a liner.
Highly soluble in water and marginal leakage will
wash out the material.
No long term seal.
Endod Dent Traumatol 2000;16:240-
250
70
71. Vital pulp therapy
Demerits:
Tunnel defects- bacterial re-infection.
The 1.5-2mm layer of sterile pulp necrotic layer may
get infected under leaking restorations thus causing
pulpitis and subsequent pulp necrosis if left
untreated .
Odontol Revy 1971;22: 379-96.
International Journal of Dental Sciences
and Research, 2014; 2(6B):1-4.
71
72. Few authors have shown that MTA may be a
superior material when compared to calcium
hydroxide. According to Mente et al., MTA
appeared to favour long term pulp vitality
after direct pulp capping when compared
with calcium hydroxide.
Journal of Endodontics 2010;36(5), 806-13
72
73. After performing a histomorphometric analysis
of pulp capping of human permanent premolars
using calcium hydroxide and MTA, Maria et al.
concluded that both the materials were
successful but calcium hydroxide was slower
than MTA in this regard .
Journal of Endodontics, 2008;34(1).
73
74. Apexification And Apexogenesis
The time taken for formation of a hard tissue
barrier with regard to calcium hydroxide, ranges
from 2–3 months and 6–18 months in the case of
pulp capping and apexification procedures
respectively .
Swed Dent J Suppl.2012; 226: 9-84.
Calcium hydroxide affects the mechanical
properties of dentin when used for a longer
period of time rendering the tooth susceptible
to fracture
74
75. Perforation management
Calcium hydroxide has to be replaced on a regular
basis since it is displaced by tissue fluids,
exhibits poor marginal integrity, and lacks the
required strength.
It is hence a temporary solution and the newer
materials like MTA have gained popularity as a
more permanent solution
Endodontics and Dental Traumatology 16, 240-50,
2000
75
76. Root resorption
The use of calcium hydroxide in deciduous teeth is
discouraged since it may induce chronic pulpal
inflammation and internal root resorption .
According to Ravi et al. calcium hydroxide-induced
resorption in deciduous teeth may be attributed to:
(1) inflammatory cytokines, which contribute to
transformation of pre-odontoclasts to odontoclasts
(2) preexisting progenitor cells with a tendency to
transform into odontoclasts, and loss of protective
layer of predentin over mineralized dentin.
Endod Dent Traumatol. 4(6), 241-52, Dec, 1988.
76
77. Root canal sealers
Calcium hydroxide-based sealers exhibit
some disadvantages such as milder
antibacterial properties, poor cohesive
strength, greater solubility, and marginal
leakage.
J Endod 2009; 1-6.
77
78. Long-term temporary dressing
Calcium hydroxide may be regarded as the dressing
material of choice because its antimicrobial effect
may last for weeks, whilst that of other materials.
78
79. Interappointment dressing
slow movement of hydroxyl ions through
dentine.
Nerwich et al. (1993) - hydroxyl ions diffused in
a matter of hours into the inner root dentine
but required 1–7 days to reach the outer root
dentine and 2–3 weeks to reach peak levels.
Hydroxyl ions diffused faster and reached
higher levels cervically more than apically.
79
80. A Comparison between the Antimicrobial Effects
of Triple Antibiotic Paste and Calcium Hydroxide
Against Entrococcus Faecali
Triple antibiotic paste with either 2%
chlorhexidine or normal saline would be the
preferred medicament against E. Faecalis and,
among its three components, minocycline has
the greatest antibacterial effect.
IEJ Iranian Endodontic Journal
2012;7(3):149-155.
Alireza et al.
80
81. Precautions
Severe chemical burns and irritation.
J Can Dent Assoc 2012;78:c57
Loss of eye sight caused by CH paste
accidentally splashed into the eye during
endodontic treatment: a case report.
Immediate action should include:
Immediate rinsing, rinsing with
0.9% sodium
chloride,administering pt’s own
blood into the conjunctival
sac,sodium edetate neutralizing.
81
83. References
A review of calcium hydroxide.International
Endodontic Journal 1990; 23:283-297.
Merits and Demerits of Calcium Hydroxide as a
Therapeutic Agent: A Review . International Journal of
Dental Sciences and Research, 2014; 2(6B):1-4.
“MTA versus calcium hydroxide as a pulp capping
agent,” Chicago: Quintessence Publishing,2002; 19:
227-245.
Fransson H,“On the repair of the dentine
barrier,”Swed Dent J Suppl. 2012;226: 9-84.
83
84. “Mechanisms of antimicrobial activity of calcium
hydroxide: a critical review,”International
Endodontic Journal, 1999;32:361-9.
Calcium hydroxide: study based on scientific
evidences. J Appl Oral Sci 2003; 11(4): 269-82.
Properties and applications of calcium hydroxide in
endodontics and dental traumatology. International
Endodontic Journal, 2011;44:697–730.
84
85. “FOR A LONG TIME I FELT THAT THE MUMMIFIED
LAYER CREATED A SEAL, LIKE A SCAB, WHICH
WAS IMMUNOLOGICALLY SIMILAR TO THE VITAL
TISSUE BENEATH AND SOMEHOW INITIATED
THE HEALING PROCESS. FOR 200 YEARS NATURE
WAITED FOR US TO FIND THE EQUIVALENT OF
THE SCAB”
HAROLD R STANLEY
Thank you
85