3. Introduction
Mineral trioxide aggregate (MTA) was developed
at Loma Linda University (Loma Linda,
California, USA)
First described in the dental scientific literature
in 1993 by Lee et al.
The chemical composition of MTA was
determined by Torabinejad et al.
It received US Food and Drug Administration
approval in 1998 and is commercially available
as Pro-Root MTA by Dentsply International .
Initially recommended as a root-end filling
material, it is currently being used for pulp
capping, pulpotomy, apexogenesis and
apexification, apical barrier formation, repair of
4. Endodontic failures may occur as a result of
leakage of irritants into the periapical tissues.
Therefore, an ideal orthograde and/or
retrograde filling material should seal the
pathways of communication between the root
canal system and its surrounding tissues; thus,
this material should be biocompatible and
dimensionally stable. This led to the
development of mineral trioxide aggregate
(MTA) materials possessing these ideal
characteristics.
5. COMPOSITION
MTA is a cement composed ofMTA is a cement composed of
Portland Cement
)75%(
• Tricalcium silicate
• Dicalcium silicate
• Tricalcium aluminate
• Tetracalcium
aluminoferrite
Gypsum
(Calcium
Sulphate)
)5%(
Bismuth Oxide
)20%(
MTA = Portland's Cement + Bismuth Oxide + Gypsum
= Radio-opacity and Good Setting Properties
Sarkar et al JOE 31 (2) Feb. 2005
6. -It also contains trace
amounts of
Silica,
calcium oxide,
magnesium oxide ,
potassium sulphate, and
sodium sulphate.
7. Difference between
WhiteWhite
MTAMTA
Secondary electron
image EDAX analysis
Calcium
Silicon
Bismuth
Oxygen
GreyGrey
MTAMTA
Secondary electron imageSecondary electron image
EDAX analysisEDAX analysis
CalciumCalcium
SiliconSilicon
BismuthBismuth
OxygenOxygen
AluminumAluminum
IronIron
Camilleri et al -Dental Materials (2005) 21, 297–303
9. MTA is essentially Portland cement (used in the
building industry as a binder in concrete) with
4:1 proportions of bismuth oxide added for
radiopacity.
However Camilleri and co-workers have shown
that MTA is composed primarily of tricalcium
and dicalcium silicate, the main constituent
elements of Portland cement, which on hydration
produce a silicate hydrate gel and calcium
hydroxide, not calcium phosphate as claimed by
Torabinejad.
10. MTA powder is Hydrophilic .
It consists of two phases – Crystalline
material is essential calcium oxide and
amorphous – Calcium phosphate.
Hydration of MTA powder result in the
formation of a colloidal gel that hardens.
The Crystalline material has prisms that have
87% Ca , 2.47% Silica, and remainder oxygen.
Amorphous material 33% calcium , 2% Carbon
11. Calcium oxide (50-75%) + Silicone dioxide(15-
25%)+ Aluminum oxide
Tricalcium Silicate + Dicalcium Silicate +
Tricalcium Aluminate
+
(Tetracalcium Aluminoferrite)(Tetracalcium Aluminoferrite)
Calcium silicate hydrated gel
(Hardens on setting)
Calcium Hydroxide contained in a silicateCalcium Hydroxide contained in a silicate
matrixmatrix
(Camilleri et al -(Camilleri et al -Dental Materials (2005) 21,Dental Materials (2005) 21,
Clinkered in a Kiln
On mixing with
water
13. MTA is available either as a box of five 1-gram
single-use packets or as premeasured water
packs for easy manipulation and application.
ProRoot liquid microampules (sterile water)
and a carrier are also provided with the packet.
It should be stored in closed sealed containers
away from moisture.
The powder is mixed with supplied sterile
water in a 3:1 powder/liquid ratio.
16. The mixing time should be less than 4 minutes,
as prolonged mixing can cause dehydration of
the mixture.
The mixture can be carried with a plastic or
metal carrier. The unused portion of MTA
powder can be stored in sterilized empty film
canisters.
MTA is uninhibited by blood or water, as
moisture is required for a better setting of the
material.
17.
18. MESSING GUN / AMALGAM
CARRIER WEST PERF REPAIR
INSTRUMENT
FLAT END OF SPOON
EXCAVATOR
AMALGAM CARRIER
SPINE TAP NEEDLE
Carriers Of MTA
19. Different types of Carrier for placement of MTADifferent types of Carrier for placement of MTA
Small plastic amalgam type
carrier.
Small Spoon excavator.
Amalgam pistolAmalgam pistol
Messing gun
Dovgan Carriers
20.
21. The hydration reaction during setting occurs
between tricalcium silicate (3CaO SiO2) and·
dicalcium silicate (2CaO SiO2) to form a calcium·
hydroxide and calcium silicate hydrate gel,
producing an alkaline pH.
The released calcium ions diffuse through
dentinal tubules, and increase their concentration
over time as the material cures.
Upon hydration, the poorly crystallized and
porous solid gel (hydrated forms of components)
that is formed solidifies to a hard structure in
approximately 3 to 4 hours (initial set), with
mean setting time of 165 ± 5 minutes.
22.
23. A study comparing white MTA (White MTA, Dentsply;
Tulsa Dental Products) to white Portland cement
showed the cements to have similar constituent
elements except for the bismuth oxide in the MTA.
MTA had less gypsum.
Decreased gypsum causes a reduction in setting time
of the cement.
Higher level of toxic heavy metals and aluminium in
Portland cement
24. Difference in the particle size distribution.
Portland cement exhibited a wide range of
sizes whereas MTA showed a uniform and
smaller particle size.
Both MTA (Pro-Root) and Portland cement
(Quikrete, Columbus, OH,USA) had similar
physical, chemical and biological properties,
and the biocompatibility of both materials was
due to the similarity in constituents
25. Results from characterization studies have
indicated PC cannot be recommended as a
suitable substitute of MTA for the following
reasons:
• The quality and composition is difficult to
predict. Studies have shown that the arsenic
content of PC is 6 times the amount of arsenic
in GMTA.
• The high solubility can lead to release of a
toxic element and early degradation of the
material, jeopardizing the long-term safety of
PC.
• Carbon dioxide in inflamed tissues readily
26. • As opposed to PC, MTA is manufactured in
laboratories as a medical material and is
approved by the U.S. Food and Drug
Administration for use in humans.
Although MTA is considered a refined form
of PC material (parent compound),
substitution with PC for MTA is discouraged
for clinical purposes.
Generally, researchers do not suggest that
MTA and PC have the same clinical, biologic,
and mechanical properties and do not co
nsider PC to be a suitable replacement for
MTA as an endodontic material
27. PROPERTIES
PHYSICAL STATE - solid (powder)
COLOR - grey/white
ODOR - no specific odor
BOILING POINT - >1000ºC
28. SETTING TIME : 2 hours 45 min – 4 hours
COMPRESSIVE STRENGTH: immediately after
setting - 40 Mpa
21 days after setting - 70 Mpa
pH :
10.2 at start of mix rises to 12.5 after 3
hours.
In experimental setting MTA is capable of
maintaining high ph for long time.
The high pH of MTA could be of clinical
significance when used in apical barrier
29. Solubility
MTA displays low or nearly no solubility,
which is attributable to addition of the
bismuth oxide.
Chemical analysis and x-ray diffraction have
demonstrated insolubility of 18.8% in water.
Although MTA forms a porous matrix
characterized by internal capillaries and water
channels with increased liquid/powder ratio—
which can increase the porosity and the
solubility further—the solubility levels of
GMTA have been shown to be stable over
time.
30. Antibacterial properties
Results showed that the freshly mixed MTA was
effective in killing the tested fungi after 1 day
of contact, whereas the 24-h set MTA was
effective after 3 days of incubation. It was
concluded that MTA (freshly mixed and 24-h set)
was effective against C. albicans.
Nazhan-Al Saad et alNazhan-Al Saad et al
Nine facultative bacteria and seven strict
anaerobes. MTA was found to have an
antibacterial effect on five of nine facultative
bacteria but no effect on any of the strict
anaerobes.
31. Periradicular reaction
As a root-end filling in vivo, less periradicular
inflammation was reported compared with
amalgam (Torabinejad et al.)
In addition, the presence of cementum on the
surface of MTA (Loma Linda University) was a
frequent finding.
It induced apical hard tissue formation with
significantly greater consistency, but not
quantity.
MTA (ProRoot) supported almost complete
regeneration of the periradicular periodontium
when used as a root end filling material on
noninfected teeth
32. BIOCOMPATIBILITY
Some studies considered that the
biocompatibility of MTA is attributable to the
release of hydroxyl ions and formation of
calcium hydroxide during the hydration
process.
Other reports had observed the formation of a
white interfacial material (precipitates) between
GMTA and tooth structure within 1 to 2 hours
when exposed to physiologic fluids (phosphate-
buffered physiologic solution) in vivo or with
simulated body fluids in vitro.
SEM and x-ray diffraction (XRD) analysis of
these precipitates revealed the presence of
chemically and structurally similar
hydroxyapatite (HA)-like structure with a
33. Regenerative Potential and
Biological Activity
MTA has the capacity to induce bone, dentin,
and cementum formation and regeneration of
periapical tissues (periodontal ligament and
cementum).
MTA provides a good biological seal and can
act as a scaffold for the formation and/or
regeneration of hard tissue (periapical).
It is an osteoconductive, osteoinductive, and
cementogenic (cementoconductive and
cementoinductive) agent.
MTA stimulates immune cells to release
34. Radiopacity
MTA has a mean radiopacity of 7.17 mm of
equivalent thickness of aluminum, which is
less than that of IRM, super EBA, amalgam,
or gutta-percha.
It has a similar radiodensity to zinc oxide
eugenol and slightly greater radiopacity
than dentin.
35.
36. Direct pulp capping
Pulp capping is indicated for teeth with
immature apices when the dental pulp is
exposed & there are no signs of irreversible
pulpitis .
In such cases ,the maintenance of pulp vitality
is extremely important , & MTA is preferred to
calcium hydroxide .
Recent studies have shown that MTA
stimulates dentin bridge formation adjacent
to the dental pulp ,
Dentinogenesis of MTA can be due to its
37. Similarly to calcium hydroxide , initially
causes necrosis by coagulation in contact
with pulp connective tissue .
This reaction may occur due to the products
high alkalinity, as the Ph is 10.2 during
manipulation and 12.5 after 3 hours.
Holland et al demonstrated the presence of
calcite crystals in contact with MTA
implanted in rat subcutaneous tissue.
Those calcite crystals attract fibronectin
which is responsible for cellular adhesion &
differentiation.
Therefore it is believed that MTA mechanism
of action is similar to that of calcium
hydroxide , but in addition ,MTA provides a
38. Operative Sequence for Pulp capping
Anaesthesia
isolation with a rubberdam
the exposesd pulp is irrigated with sodium
hypochlorite to control bleeding.
MTA powder is mixed with sterile water & the
mixture is placed in contact with the exposure
using a dovgan carrier.
Compress the mixture against the exposure site
with a moist cotton pellet.
Place a moist cotton pellet over the MTA & fill
the rest of the cavity with a temporary filling
material .
After 4 hours the patient is seen again, the
rubber dam is positioned the temporary filling
42. Verification of the setting of
MTA at 48 h.
Disinfection of
exposure site by
rinsing with
5.25%
sodium
hypochlorite.
Pulp exposure presenting with
moderate bleeding.
Immediate postoperative
periapical radiograph
showing
pulp capping with MTA,
cotton and temporary
filling material.
43. Follow-up periapical radiograph at 11
months showing
maturogenesis of the root.
Final coronal restoration with composite.
Follow-up periapical
radiograph at 4 months
presenting
with continued root
development.
44. Pulpotomy agent
MTA has been proposed as a potential
medicament for pulpotomy procedures as well
as capping of pulps with reversible pulpitis.
MTA was tested in dog s teeth as a pulp′
capping material and produced favorable pulp
responses.
There are reports of complete dentine bridge
formation when MTA was used as a pulp
capping agent.
Hard tissue bridge deposition next to MTA
45. All irrigation should be performed
before the material is placed because
irrigation after placement will cause
significant wash out of the material.
MTA was less cytotoxic and non-
mutagenic. This further supports the
superiority of MTA over formocresol as
a pulpotomy medicament.
49. Pulpotomy Procedure
Anaesthesia
Isolation with a rubber dam.
Caries should be removed using a
caries detector with a slow speed round
burs & spoon excavators.
Once caries has been entirely removed,
irrigate with 5.25% naocl for 5-10
minutes to achieve homeostasis and
ensure complete debridement.
Rinse out naocl and ensure that the
chamber is debris free.
Place a 1-1.5 mm thick layer of freshly
50.
51. Place a wet ,thinned ,flattened cotton pellet over
the MTA.
The cotton pellet provides the moisture MTA
requires for a proper set.
Temporize with either light cured Photocure ,IRM
or other suitable material.
Recall after a week
Once proper setting of MTA has been
ascertained , the tooth can be restored
52. Apexification
Although MTA & Calcium hydroxide both exhibit
similar alkaline Ph levels, MTA also shows
excellent marginal adaptability & is non-
resorbable.
MTA allow apexification cases to be restored
after approximately 2 weeks as opposed to
traditional Calcium hydroxide therapy, where
apexification may require many months .
56. Rubber dam isolation
Extirpate the pulp and clean the root canal
system using endodontic instruments and
5.25% Naocl irrigation.
Place calcium hydroxide paste in the root canal
system for one week to fully disinfect the canal
system.
When the patient returns in one week rinse
ca(oh)2 paste from the root canal system with
naocl irrigation and dry with paper points.
ProceduProcedu
re:re:
57. Place MTA in the canals and condense to the
apical end of the root canal to create a 3-
4mm apical plug .
Radiographically, check the extension &
quality of fill .
Place a moist cotton pellet or wet paper
point in the canal & close the access cavity
with IRM or Cavit .
The patient can return in one week for
obturation rest of the canal or the final
obturation delayed until healing completed
58. Apexification
Preoperative radiograph of the
maxillary left central incisor.
The patient is 55-years-old and
this tooth (with an open apex) has
not responded to previous
therapy
with calcium hydroxide
Intraoperative film with
the Dovgan carrier in place
Three millimeters of MTA
have been positioned at the
foramen to form the apical
barrier
After the MTA is set, the
thermoplastic gutta-percha
has been used to obturate
the root canal.
59. Perforation Repair with MTA
Mta can today be considered the ideal material
to seal perforations .
Cementum has been shown to grow over mta
allowing normal attachment of the
periodontal ligament .
Furthermore, mta dosen’t require a barrier &
is not affected by moisture or blood
contamination & seals better than any other
material in use today.( Amalgam, super EBA
,IRM ,composite resins )
63. MTA APPLIED ALONG THE COLLAGENMTA APPLIED ALONG THE COLLAGEN
HEALING OF PERFORATIONHEALING OF PERFORATION
64. IMPORTANCE OF COLLGENIMPORTANCE OF COLLGEN
•HIGH DEGREE OF COMPATIBILITYHIGH DEGREE OF COMPATIBILITY
(KEISER et al-2000)(KEISER et al-2000)
•ROUGH SURFACE OF MTAROUGH SURFACE OF MTA
(FRID LAND & ROSADO 2003)(FRID LAND & ROSADO 2003)
•MTA IS NOT A HARD MATERIALMTA IS NOT A HARD MATERIAL
(TORABINEJAD et al-1995)(TORABINEJAD et al-1995)
65. Operative Sequence
First visitFirst visit
Isolation with a rubber dam .
Cleansing of the perforation site.
In case of bacterial contamination ,
application of calcium hydroxide for 1
week .
Application of 2 to 3 mm of MTA .
Radiographs to check the correct
positioning of the materials.
Application of a small , wet cotton pellet in
contact with MTA.
Temporary cement.
72. Use of paper
point to
locate the
perforation.
LATERAL PERFORATION AND STRIPLATERAL PERFORATION AND STRIP
PERFORATIONPERFORATION
Radicular
Perforation
76. ROOT END FILLING
Establish a seal between the root canal space
and periapical tissues.
Acc to Gartner and DornAcc to Gartner and Dorn
1) able to prevent leakage of bacteria & their
byproducts into the periradicular tissues.
2) nontoxic
3)noncarcinogenic.
4)biocompatible.
5)insoluble in tissue fluids.
6)dimensionally stable.
7)unaffected by moisture during setting.
8)easy to use.
9)radiopaque.
77. Cements and sealers such as ZnOE, IRM, Super
EBA, cavit, zincpolycarboxylate, zinc phosphate
and glass Ionomer cements, mineral trioxide
aggregate, calcium phosphate cement and bone
cement have also been employed for retro-
fillings.
Other commonly used materials are - composite
resin (with and without bonding agent) and
gutta-percha.
The less commonly used materials are laser,
citric acid demineralization, ceramic inlay, teflon,
mixture of powdered dentin & sulfathiazole and
78. MTA provides superior seal when
compared with Amalgam, IRM and
Super EBA. and
Most characteristic tissue reaction
of MTA was the presence of
connective tissue after the first
postoperative week.
Studies have shown that osteoblasts
have favorable response to MTA as
compared to IRM and amalgam.
MTA Angelus (120 days). H.E. 40 X.
Presence
79. With longer duration, new cementum was
found of the surface of the material.
In a two year follow-up study with MTA as root-
end filling material resulted in a high success
rate.
80. Such studies support further development of
MTA to reduce the long setting time and
difficulty in manipulation for use as a root-end
filling material.
Studies evaluating MTA as a retrofilling
material have shown less periapical
inflammation, presence of a fibrous capsule
and formation of new cementum layer in
contact with the material surface in many
cases.
81. MTA was able to induce apical healing even
when placed in infected canals.
It may be assumed that neoformed cementum
deposition on the entire material surface
(biological sealing), as observed with MTA,was
an important histopathologic event to be
considered because it isolated the content
remaining within the intracanal space and root-
end filling material from the apical tissues.
82. Root- end fillings
Costa et al JOE 2003 Mar
thickness of 4 mm is most adequate for the use of MTA as a root-
end filling material.
83. Treatment of Internal &
external Root resorption
Moisture present in these preparations turns
the ‘MTA’ soupy & difficult to condense.
Moisture can be drawn out of the MTA after
placement with a dry paper point or cotton
pellet
MTA is often pressed into the desired location &
not condensed.
All irrigation should be performed before the
MTA is placed .
Any irrigation after placement will cause
significant washout of the material
The preparation or resorptive defect does not
have to be perfectly dry, but most of the fluid
has to be removed.
84. If MTA is placed from inside the tooth , a
moist cotton pellet or paper point should be
placed against it, because the presence of
moisture is essential for the material to set.
The access cavity is then closed .
Most internal repairs with MTA requires a
second visit to complete the root canal
therapy or restoration.
85. Root Resorption
The patient was referred with a large resorptive
lesion in the root of his maxillary right central
incisor. A pulpectomy was performed and
progressive
débridement of granulation tissue was
accomplished by
monthly irrigation with sodium hypochlorite and
placement of calcium hydroxide.
After three months, débridement of the lesion was
complete. The calcium hydroxide was removed, the
canal was dried and the resorptive defect was
repaired internally with MTA. The clinician placed
a post that extended apically to the resorptive
defect
and restored the tooth with resin composite in
preparation
for placement of a crown.
89. Prophylactic treatment of Dens in Dente
Clinical view of the crown of the
maxillary right central incisor Preoperative radiograph. Note the periapical radiolucency,
the unusual anatomy, and the wide open apex.
Intraoperative radiograph. Note
the thickness of MTA without any
overfilling.
Postoperative radiograph Two-year recall.
90. A comparative study of selected properties of ProRoot
mineral trioxide aggregate and two Portland cements
G. Danesh IEJ 2006
Aim To compare solubility, microhardness and
radiopacity of ProRoot MTA with two Portland
cements (PC: CEM I and CEM II).
Methodology
Solubility: for standardized samples (n ¼
12/group) ring moulds were filled with the
cements. These samples were immersed in
double distilled water for 1 min, 10 min, 1 h,
24 h, 72 h, and 28 days.
Mean loss of weight was determined.
Microhardness: five samples of each cement
were produced.
91. Radiopacity:
Five samples per cement were produced.
These samples were tested according to the
ISO standards to compare their radiodensity
to that of an aluminium step wedge (1–9 mm).
Differences between the three materials with
respect to their solubility, microhardness and
radiopacity were analysed using anova and
Student– Newman–Keuls.
92. Results
After 28 days MTA was of low solubility(0.78%)
compared with CEM I (31.38%) and CEM II (33.33%).
At exposure times >1 min the two PCs were
significantly more soluble than MTA (P < 0.05).
The microhardness for MTA was significantly higher
(39.99 HV; P < 0.001) compared with the two PC (CEM I:
16.32 HV; CEM II: 13.51 HV).
MTA was significantly more radiopaque (5.34 mm Al)
than CEMI (3.32 mm Al) and CEM II (2.52 mm Al) (P <
0.05),whereas CEM I was significantly more
radiopaque than CEM II (P < 0.05).
Conclusions
Mineral trioxide aggregate displayed superior material
properties than both Portland cements.
93. The effect of mineral trioxide aggregate on the
apexification and periapical healing of teeth with
incomplete root formation.
W. T. Felippe,IEJ 2006
Aim
To evaluate the influence of mineral trioxide
aggregate (MTA) on apexification and periapical
healing of teeth in dogs with incomplete root
formation and previously contaminated canals
and to verify the necessity of employing calcium
hydroxide paste before using MTA.
Methodology Twenty premolars from two 6-
month old dogs were used. After access to the
root canals and complete removal of the pulp,
the canal systems remained exposed to the oral
environment for 2 weeks. Canal preparation was
then carried out using Hedstrom files, under
irrigation with 1% sodium hypochlorite, 1 mm
94. The other eight teeth in each animal were
divided into two experimental groups.
The apical thirds of the canals of group 1 were
filled with MTA. In the teeth of group 2, the
canals were dressed with a calcium hydroxide–
propylene glycol paste.
After 1 week, the paste was removed and the
apical third was filled with MTA.
All teeth were restored with reinforced zinc
oxide cement (IRM) and amalgam.
The animals were killed 5 months later, and
blocks of the teeth and surrounding tissues
were submitted to histological processing.
The sections were studied to evaluate seven
parameters: formation of an apical calcified
tissue barrier, level of barrier formation,
95. Results
Significant differences (P < 0.05) were found in
relation to the position of barrier formation
and MTA extrusion.
The barrier was formed in the interior of the
canal in 69.2% of roots from MTA group only.
In group 2, it was formed beyond the limits of
the canal walls in 75% of the roots.
MTA extrusion occurred mainly inroots from
group 2.
There was similarity between the groups for
the other parameters.
Conclusions Mineral trioxide aggregate used
after root canal preparation favoured the
occurrence of the apexification and periapical
healing. The initial use of calcium hydroxide
96. Effect of mineral trioxide aggregate on proliferation
of cultured human dental pulp cells
T. Takita IEJ2006
To investigate the effect of mineral trioxide
aggregate (MTA) on the proliferation of human
dental pulp (HDP) cells ex-vivo.
Methodology
Humandental pulp cells were cultured with
MTA or calcium hydroxide-containing cement
(Dycal) using culture plate inserts. Control cells
were cultured with culture plate inserts only.
Cell proliferation was measured for up to 14
days using a Cell Counting kit, and the
concentration of calcium ions released fromthe
tested materials was assessed using a Calcium
E-test kit.
To confirm that the effect of MTA was
97. Effect of mineral trioxide aggregate on proliferation
of cultured human dental pulp cells.
T. Takita IEJ2006
To investigate the effect of mineral trioxide
aggregate (MTA) on the proliferation of human
dental pulp (HDP) cells ex-vivo.
Methodology
Humandental pulp cells were cultured with
MTA or calcium hydroxide-containing cement
(Dycal) using culture plate inserts. Control cells
were cultured with culture plate inserts only.
Cell proliferation was measured for up to 14
days using a Cell Counting kit, and the
concentration of calcium ions released fromthe
tested materials was assessed using a Calcium
E-test kit.
To confirm that the effect of MTA was
attributable to released calcium ions, cell
98. Results
Mineral trioxide aggregate significantly
stimulated cell proliferation after 12 days,
whereas Dycal had no such effect.
The number of calcium ions released from MTA
was significantly higher than that released
from Dycal.
Following the addition of calcium chloride, cell
proliferation increased in a dose-dependent
manner after 12 days.
Moreover, cell proliferation showed a similar
pattern whether a given concentration of
calcium ions was produced by calcium chloride
or by release from MTA.
Conclusions
99. Ex vivo biocompatibility tests of regular and white
forms of mineral trioxide aggregate
D. A. Ribeiro,IEJ 2006
Aim
To examine the genotoxicity and cytotoxicity
of regular and white mineral trioxide
aggregate (MTA) ex vivo by the single-cell gel
(comet) assay and trypan blue exclusion test,
respectively.
Methodology
Aliquots of 1 104 Chinese hamster ovary·
cells were incubated at 37 C for 3 h with grey
and white forms of MTA at final
concentrations ranging from 1 to 1000 lg
mL)1.
The negative control group was treated with
vehicle control phosphate buffer solution for
3 h at 37 C and the positive control group was
treated with methyl metasulfonate (at 1 lg
mL)1) for 1 h at 37 C.
100. and resuspended with fresh medium.
Each individual treatment was repeated three times
consecutively to ensure reproducibility. Parameters
from single-cell gel (comet) and cytotoxicity assays
were assessed by the Kruskal–Wallis nonparametric
test.
Results
Neither compounds produced genotoxic effects with
respect to the single-cell gel (comet) assay in all
concentrations evaluated.
In the same way, the dose–response relationships of
all compounds tested at concentrations ranging from
1 to 1000 lg mL)1 on cell viability assessed by the
trypan blue assay displayed no statistically significant
differences (P > 0.05) for either endodontic material.
101. Biological response of pulps submitted to different
capping materials
Andre briso 2006
ABSTRACT:
Pulp capping is a procedure that comprises adequate
protection of the pulp tissue exposed to the oral
environment, aiming at the preservation of its vitality
and functions.
This study evaluated the response of the dental pulps
of dog teeth to capping with mineral trioxide aggregate
(MTA) or calcium hydroxide .
For that purpose, 37 teeth were divided into two
groups, according to the capping material employed.
Two dogs were anesthetized and, after placement of a
rubber dam, their pulps were exposed in a standardized
manner and protected with the experimental capping
materials.
The cavities were then sealed with resin-modified glass
ionomer cement and restored with composite resin.
102. After sixty days, the animals were
killed and the specimens were
processed in order to be analyzed
with optic microscopy.
It was observed that MTA presented a
higher success rate compared to
calcium hydroxide, presenting a lower
occurrence of infection and pulp
necrosis.
103. conclusion
Collectively, these studies have shown that MTA is a
biocompatible material.
Mineral Trioxide Aggregate is a new material that
possesses numerous exciting possibilities for pulpal
therapy.
It is a promising material with an expanding
foundation of research.
MTA, with an excellent long term prognosis, relative
ease at which it can be used and with its numerous
exciting clinical applications promises to be one of the
most versatile materials of this century in the field of
dentistry.
Endodontic failures may occur as a result of leakage of irritants into the periapical tissues.Therefore, an ideal orthograde and/or retrograde filling material should seal the pathways of communication between the root canal system and its surrounding tissues; thus, this material should be biocompatible and dimensionally stable. This led to the development of mineral trioxide aggregate (MTA) materials possessing these ideal characteristics.