Dental Hypotheses

: 2014  |  Volume : 5  |  Issue : 1  |  Page : 14--15

Mixing MTA with phosphate buffered solution can improve its physical properties and increase favorable outcome

Naghmeh Meraji 
 Tehran University of Medical Sciences, School of Dentistry, Tehran, Iran

Correspondence Address:
Naghmeh Meraji
Tehran University of Medical Sciences, School of Dentistry, Tehran


Introduction: Encountering environmental situations that have an adverse effect on the properties of Mineral Trioxide Aggregate (MTA) is inevitable and unfortunately common. In many cases MTA does not set and the clinician is forced to apply this cement again. This occurrence may affect the outcome of endodontic treatments such as perforation repair. Therefore, strategies should be considered to overcome this matter. Various studies have been conducted that mixed several substances with MTA to reverse the adverse effects on this material but still we face this problem. The Hypothesis: In this paper, we propose a hypothesis that mixing MTA with phosphate buffered solution (PBS) may reverse the adverse environmental effects and may help us overcome this clinical problem. Evaluation of the Hypothesis: PBS is a synthetic solution containing phosphate which is commonly used for mimicking in vivo situations in laboratory studies. Considering that some studies have shown that when MTA encounters tissue fluids containing phosphorous its properties improve, we suggest that mixing this cement with PBS can at least reverse the adverse effect of the environment. It should be noted that the better the properties of these cements, the better the outcome of treatment can be.

How to cite this article:
Meraji N. Mixing MTA with phosphate buffered solution can improve its physical properties and increase favorable outcome.Dent Hypotheses 2014;5:14-15

How to cite this URL:
Meraji N. Mixing MTA with phosphate buffered solution can improve its physical properties and increase favorable outcome. Dent Hypotheses [serial online] 2014 [cited 2021 Apr 15 ];5:14-15
Available from:

Full Text


With the advancement in science, more complicated treatment plans are carried out by clinicians. For instance now a day's treatments such as perforation repair, apical surgery, vital pulp therapy, and apical plugs are commonly carried out. Therefore the application of bioactive cements such as mineral trioxide aggregate (MTA), which are used in these complicated procedures, have been growing. The physical properties of MTA have an important influence on the outcome of these complicated procedures. [1] Furthermore it has been well-documented that the environmental conditions encountered by MTA have a significant effect on its physical properties. For instance acidic pH, which is common in cases of infection, [2] can have an adverse effect on the physical properties of MTA such as its setting, microhardness, and compressive strength. [3],[4],[5] Moreover, blood contamination can also have adverse effects on the properties of this material. [6],[7]

Considering the clinical applications of MTA, this hydraulic cement is commonly encountered by environmental situations that weaken its physical properties. Therefore to improve the outcome of these complicated treatments, some strategies must be considered to compensate and reverse these negative effects.

 The Hypothesis

We propose a hypothesis as follows

MTA is a silicate-based cement. It consists of calcium silicate, calcium carbonate, calcium sulfate, etc. [8] Its hydration process initiates when the cement is mixed with water. [9] When this hydraulic cement comes in contact with tissue fluids which contain phosphate, hydroxyapatite is formed. [9],[10] As a result, several of the physical properties of this material such as the hydration process are improved. [5]

Given the above, the author hypothesizes that mixing MTA with a phosphate buffered solution (PBS), a synthetic phosphate containing solution, can improve the properties of this hydraulic cement and improve the outcome of treatment; especially in cases with infection/or blood contamination.

 Evaluation of the Hypothesis

PBS is a simulated tissue fluid containing phosphate [11] that can be used for the purpose of mimicking in vivo conditions in laboratory studies. [5],[12],[13] It is easily available and can be sterilized before application.

As described above, the contact of MTA with tissue fluids containing phosphate during the setting process can improve its physical properties. [5] So in cases where MTA is in contact with blood or acidic pH and the physical properties of this cement is compromised, maybe these adverse effects can be compensated and reversed by mixing this cement with PBS. If so, the outcome of complicated treatments such as perforation repairs, apical surgery, and vital pulp therapy can be improved and tooth extraction can be prevented. By preventing tooth extraction, there will be no need for more complex treatment plans such as dental implants and following that the function of teeth can be maintained. It should be mentioned that the maintenance of the oral functions is the fundamental aim of all dental treatments.


The authors deny any conflicts of interest related to this article.


1Main C, Mirzayan N, Shabahang S, Torabinejad M. Repair of root perforations using mineral trioxide aggregate: A long-term study. J Endod 2004;30:80-3.
2Nekoofar MH, Namazikhah MS, Sheykhrezae MS, Mohammadi MM, Kazemi A, Aseeley Z, et al. pH of pus collected from periapical abscesses. Int Endod J 2009;42:534-8.
3Namazikhah MS, Nekoofar MH, Sheykhrezae MS, Salariyeh S, Hayes SJ, Bryant ST, et al. The effect of pH on surface hardness and microstructure of mineral trioxide aggregate. Int Endod J 2008;41:108-16.
4Kayahan MB, Nekoofar MH, Kazandag M, Canpolat C, Malkondu O, Kaptan F, et al. Effect of acid-etching procedure on selected physical properties of mineral trioxide aggregate. Int Endod J 2009;42:1004-14.
5Lee YL, Lee BS, Lin FH, Yun Lin A, Lan WH, Lin CP. Effects of physiological environments on the hydration behavior of mineral trioxide aggregate. Biomaterials. 2004;25:787-93.
6Nekoofar MH, Oloomi K, Sheykhrezae MS, Tabor R, Stone DF, Dummer PM. An evaluation of the effect of blood and human serum on the surface microhardness and surface microstructure of mineral trioxide aggregate. Int Endod J 2010;43:849-58.
7Vanderweele RA, Schwartz SA, Beeson TJ. Effect of blood contamination on retention characteristics of MTA when mixed with different liquids. J Endod 2006;32:421-4.
8Torabinejad M, Hong CU, McDonald F, Pitt Ford TR. Physical and chemical properties of a new root-end filling material. J Endod 1995;21:349-53.
9Camilleri J. Hydration mechanisms of mineral trioxide aggregate. Int Endod J 2007;40:462-70.
10Camilleri J. Characterization of hydration products of mineral trioxide aggregate. Int Endod J 2008;41:408-17.
11Marques MR, Loebenberg R, Almukainzi M. Simulated biological fluids with possible application in dissolution testing. Dissolut Technol 2011;18:15-28.
12Asgary S, Eghbal MJ, Parirokh M, Ghoddusi J. Effect of two storage solutions on surface topography of two root-end fillings. Aust Endod J 2008;35:147-52.
13Shokouhinejad N, Nekoofar MH, Razmi H, Sajadi S, Davies TE, Saghiri MA, et al. Bioactivity of endosequence root repair material and bioaggregate. Int Endod J 2012;45:1127-34.