Mineral trioxide aggregate
Encyclopedia
Mineral trioxide aggregate is a material used to fill the root canals of teeth as part of root canal therapy. It has the ability to encourage hard tissue deposition similar to Calcium hydroxide
effect. Also both have the same biological and histological properties.
, 4. tetracalcium aluminoferrite, 5. calcium sulfate
and 6. bismuth oxide.
It was developed by the research pioneer and Endodontist, Dr. Mahmoud Torabinejad at Loma Linda University, and his patient Dean White (US Patents 5,769,638 and 5,415,547).
MTA has the same composition as Portland cement
but has added bismuth oxide for radiopacity - making it visible on an x-ray. However, dental materials are required to have high purity and be lead and arsenic free, unlike portland cement. Two brands are commonly available ProRoot MTA. Another brand is MTA-Angelus (not sold in the USA due to the patent). Both materials contain roughly 20% bismuth oxide.
Source: http://www.scielo.br/pdf/%0D/jaos/v14n5/a02v14n5.pdf
around the margins.
5.Very alkaline material (high pH when mixed with water).
6. As a root-end filling material MTA shows less leakage than other commonly used root-end filling materials, which means bacterial penetration will be less when using MTA.
7. You need to be infection free when applying MTA to clear the acidic environment, because acidic infections will prevent MTA from setting..
compressive strength is develops over a period of 28 days, like portland cement, and when mixed in a powder to liquid ratio of more than 3 to 1- strengths of more than 50 MPa are achieved.
MTA material requires a few hours for the initial and final setting, which is not common in dental materials. Also the material has a tendency to washout when rinsed by a dentist. These problems have not been addressed in commercial products, although research has been published.
Several authors have published papers complaining about the high cost of ProRoot MTA- which has prevented wider use.
.
Proper isolation should be completed using a rubber dam and cotton pellet.Disinfection
of the cavity with sodium hypochlorite. then application of MTA over the exposure area. restoration of the cavity with amalgam
or composite is done. MTA provides a higher incidence and faster rate of reparative dentin
formation without the pulpal inflammation.
… root canal therapy is performed, putty mixture of MTA is inserted in the canal using gutta percha.
The MTA will provide structure and strength to the tooth by replacing the resorbed tooth structure.
In external resorption
… after root canal therapy is performed.
Flap
is raised over the tooth and the defect removed from the root surface with a round bur. Retrograde application of MTA to the root surface is then completed.
If it happens, one should finish cleaning & shaping of the canal , irrigate the canal with sodium hypochlorite to disinfect it and dry it with a paper point.
When the perforation occurs at the furcation (between roots)… it can be healed by using MTA material in the perforation to seal it from the coronal area- thus preventing bacterial ingress. Make sure that you can locate the canal while the MTA has not set and remove the excess material from the area. Close the tooth as above and do the root canal the next visit.
Apexification (Necrotic pulp)
When the root is not completely formed in adolescents, but an infection occurs with a no vital pulp. In case of non-vital pulp: 1. Isolate the tooth with a rubber dam 2. perform root canal treatment. 3. Mix the MTA and plug it down to the apex of the tooth, creating a 2 mm thickness of plug. 5. Wait for it to set; then fill in the canal with cement and gutta percha.
Apexogenesis (Vital pulp)
The proces of maintaining pulp vitality during pupl treatment to allow continued development of the entire root (apical closure occurs appeoximately 3 years after eruption).
1. Isolate the tooth with a rubber dam 2. Perform a pulpotomy procedure. 3. Place the MTA material over the pulp and close the tooth with temporary cement until the apex is completely formed.
Contraindication:
1. Avulsed teeth
2. Unrestorable teeth
3. Severe horizontal fracture teeth
4. Necrotic teeth
Prognosis:
Good when pulp capping or shallow pulpothomy is done correctly; conventional pulpotomy is slightly less successful.
Calcium hydroxide
Calcium hydroxide, traditionally called slaked lime, is an inorganic compound with the chemical formula Ca2. It is a colourless crystal or white powder and is obtained when calcium oxide is mixed, or "slaked" with water. It has many names including hydrated lime, builders lime, slack lime, cal, or...
effect. Also both have the same biological and histological properties.
Composition
It is composed of 1. tricalcium silicate, 2. dicalcium silicate, 3. tricalcium aluminateTricalcium aluminate
Tricalcium aluminate Ca3Al2O6, often formulated as 3CaO·Al2O3 to highlight the proportions of the oxides from which it is made, is the most basic of the calcium aluminates...
, 4. tetracalcium aluminoferrite, 5. calcium sulfate
Calcium sulfate
Calcium sulfate is a common laboratory and industrial chemical. In the form of γ-anhydrite , it is used as a desiccant. It is also used as a coagulant in products like tofu. In the natural state, unrefined calcium sulfate is a translucent, crystalline white rock...
and 6. bismuth oxide.
| Tricalcium silicate Alite Alite is a name for tricalcium silicate, Ca3SiO5, sometimes formulated as 3CaO·SiO2 . It is the major, and characteristic, mineral phase in Portland cement. The name was given by Törneborn in 1897 to a crystal identified in microscopic investigation of Portland cement... (CaO)3.SiO2 |
| Dicalcium silicate Belite Belite is an industrial mineral important in Portland cement manufacture, a name for dicalcium silicate, Ca2SiO4, sometimes formulated as 2 CaO · SiO2 .... (CaO)2.SiO2 |
| Tricalcium aluminate Tricalcium aluminate Tricalcium aluminate Ca3Al2O6, often formulated as 3CaO·Al2O3 to highlight the proportions of the oxides from which it is made, is the most basic of the calcium aluminates... (CaO)3.Al2O3 |
| Tetracalcium aluminoferrite Calcium aluminoferrite Calcium aluminoferrite is a dark brown crystalline phase commonly found in cements. In the cement industry it is termed ferrite... (CaO)4.Al2O3.Fe2O3 |
| Gypsum Gypsum Gypsum is a very soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. It is found in alabaster, a decorative stone used in Ancient Egypt. It is the second softest mineral on the Mohs Hardness Scale... CaSO4 · 2 H2O |
| Bismuth oxide Bi2O3 |
It was developed by the research pioneer and Endodontist, Dr. Mahmoud Torabinejad at Loma Linda University, and his patient Dean White (US Patents 5,769,638 and 5,415,547).
MTA has the same composition as Portland cement
Portland cement
Portland cement is the most common type of cement in general use around the world because it is a basic ingredient of concrete, mortar, stucco and most non-specialty grout...
but has added bismuth oxide for radiopacity - making it visible on an x-ray. However, dental materials are required to have high purity and be lead and arsenic free, unlike portland cement. Two brands are commonly available ProRoot MTA. Another brand is MTA-Angelus (not sold in the USA due to the patent). Both materials contain roughly 20% bismuth oxide.
Source: http://www.scielo.br/pdf/%0D/jaos/v14n5/a02v14n5.pdf
Properties & Deficiencies
1.Biocompatible with periradicular tissues, 2.non-toxic, 3.non-resorbable and 4.minimal or no leakageLeakage
Leakage may refer to:*Leakage *Memory leak, in computer science*Leakage *Leakage *Leakage *Leakage...
around the margins.
5.Very alkaline material (high pH when mixed with water).
6. As a root-end filling material MTA shows less leakage than other commonly used root-end filling materials, which means bacterial penetration will be less when using MTA.
7. You need to be infection free when applying MTA to clear the acidic environment, because acidic infections will prevent MTA from setting..
compressive strength is develops over a period of 28 days, like portland cement, and when mixed in a powder to liquid ratio of more than 3 to 1- strengths of more than 50 MPa are achieved.
MTA material requires a few hours for the initial and final setting, which is not common in dental materials. Also the material has a tendency to washout when rinsed by a dentist. These problems have not been addressed in commercial products, although research has been published.
Several authors have published papers complaining about the high cost of ProRoot MTA- which has prevented wider use.
Pulp capping
In case of mechanical exposure that occurs during cavity preparation and not a pathological exposure due to cariesCaries
Caries is a progressive destruction of any kind of bone structure, including the skull, ribs and other bones, or the teeth. Caries can be caused by osteomyelitis, which is a microorganism disease. A disease that involves caries is mastoiditis, an inflammation of the mastoid process, in which the...
.
Proper isolation should be completed using a rubber dam and cotton pellet.Disinfection
Disinfection
Disinfectants are substances that are applied to non-living objects to destroy microorganisms that are living on the objects. Disinfection does not necessarily kill all microorganisms, especially nonresistant bacterial spores; it is less effective than sterilisation, which is an extreme physical...
of the cavity with sodium hypochlorite. then application of MTA over the exposure area. restoration of the cavity with amalgam
Amalgam (dentistry)
Amalgam is an alloy containing mercury. The term is commonly used for the amalgam employed as material for dental fillings, which consists of mercury , silver , tin , copper , and other trace metals...
or composite is done. MTA provides a higher incidence and faster rate of reparative dentin
Dentin
Dentine is a calcified tissue of the body, and along with enamel, cementum, and pulp is one of the four major components of teeth. Usually, it is covered by enamel on the crown and cementum on the root and surrounds the entire pulp...
formation without the pulpal inflammation.
Internal and external root resorption
In internal resorptionInternal resorption
Internal resorption is an unusual condition of a tooth when the dentin and pulpal walls begin to resorb centrally within the root canal. The first evidence of the lesion may be the appearance of a pink-hued area on the crown of the tooth; this condition is referred to as pink tooth of Mummery,...
… root canal therapy is performed, putty mixture of MTA is inserted in the canal using gutta percha.
The MTA will provide structure and strength to the tooth by replacing the resorbed tooth structure.
In external resorption
External resorption
External resorption is a condition of a tooth where the root surface is lost. This can be caused by chronic inflammation, cysts, tumors, trauma, reimplantation of a tooth, or sometimes the cause is unknown.-References:...
… after root canal therapy is performed.
Flap
Flap
Flap may refer to:* Flap , a hinged surface on the trailing edge of an airplane wing* Roof flap, an aerodynamic feature of race cars* Flapping, one of the basic mechanics of flight in birds...
is raised over the tooth and the defect removed from the root surface with a round bur. Retrograde application of MTA to the root surface is then completed.
Lateral or furcation perforation
Lateral perforation occurs due to wrong direction of instrumentation during cleaning & shaping of the canal by the dentist.If it happens, one should finish cleaning & shaping of the canal , irrigate the canal with sodium hypochlorite to disinfect it and dry it with a paper point.
When the perforation occurs at the furcation (between roots)… it can be healed by using MTA material in the perforation to seal it from the coronal area- thus preventing bacterial ingress. Make sure that you can locate the canal while the MTA has not set and remove the excess material from the area. Close the tooth as above and do the root canal the next visit.
Apexification (Necrotic pulp)
When the root is not completely formed in adolescents, but an infection occurs with a no vital pulp. In case of non-vital pulp: 1. Isolate the tooth with a rubber dam 2. perform root canal treatment. 3. Mix the MTA and plug it down to the apex of the tooth, creating a 2 mm thickness of plug. 5. Wait for it to set; then fill in the canal with cement and gutta percha.
Apexogenesis (Vital pulp)
The proces of maintaining pulp vitality during pupl treatment to allow continued development of the entire root (apical closure occurs appeoximately 3 years after eruption).
1. Isolate the tooth with a rubber dam 2. Perform a pulpotomy procedure. 3. Place the MTA material over the pulp and close the tooth with temporary cement until the apex is completely formed.
Contraindication:
1. Avulsed teeth
2. Unrestorable teeth
3. Severe horizontal fracture teeth
4. Necrotic teeth
Prognosis:
Good when pulp capping or shallow pulpothomy is done correctly; conventional pulpotomy is slightly less successful.
See also
- Calcium hydroxideCalcium hydroxideCalcium hydroxide, traditionally called slaked lime, is an inorganic compound with the chemical formula Ca2. It is a colourless crystal or white powder and is obtained when calcium oxide is mixed, or "slaked" with water. It has many names including hydrated lime, builders lime, slack lime, cal, or...
- Internal resorptionInternal resorptionInternal resorption is an unusual condition of a tooth when the dentin and pulpal walls begin to resorb centrally within the root canal. The first evidence of the lesion may be the appearance of a pink-hued area on the crown of the tooth; this condition is referred to as pink tooth of Mummery,...
- External resorptionExternal resorptionExternal resorption is a condition of a tooth where the root surface is lost. This can be caused by chronic inflammation, cysts, tumors, trauma, reimplantation of a tooth, or sometimes the cause is unknown.-References:...
- Endodontic therapyEndodontic therapyEndodontic therapy is a sequence of treatment for the pulp of a tooth which results in the elimination of infection and protection of the decontaminated tooth from future microbial invasion...
External links
- http://www.endomail.com/articles/ad38mta.html
- http://www.endoweb.com/dentist/nah_ber2.htm
- http://www.jcd.org.in/text.asp?2010/13/2/106/66723