Mineral trioxide aggregate in paediatric dentistry

Objective.  The aim of this study was to present a review of the reported literature on: (i) the physical and chemical properties; and (ii) clinical applications of mineral trioxide aggregate (MTA) in the practice of paediatric dentistry.
Method.  Electronic literature search of scientific papers from January 1993 to June 2008 was carried out on the MEDLINE, Embase, Entrez Pubmed, and Scopus databases using specific key words. The search yielded 448 papers, out of which 100 were identified as conforming to the applied criteria. These papers formed the basis of the review and the clinical scenarios presented which demonstrate the application of MTA in the practice of paediatric dentistry.
Conclusion.  Paediatric dentists have successfully employed MTA in a variety of endodontic/restorative applications since the late 1990s. Clinical impressions have generally been favourable and support the findings of laboratory and animal-based investigations. Very few clinical studies have been reported so far in humans, and although these have been positive, the body of research is currently insufficient to enable a meaningful systematic review and meta-analysis.     

Mineral trioxide aggregate material use in endodontic treatment: a review of the literature.

OBJECTIVE: The purpose of this paper was to review the composition, properties, biocompatibility, and the clinical results involving the use of mineral trioxide aggregate (MTA) materials in endodontic treatment. METHODS: Electronic search of scientific papers from January 1990 to August 2006 was accomplished using PubMed and Scopus search engines (search terms: MTA, GMTA, WMTA, mineral AND trioxide AND aggregate). RESULTS: Selected exclusion criteria resulted in 156 citations from the scientific, peer-reviewed dental literature. MTA materials are derived from a Portland cement parent compound and have been demonstrated to be biocompatible endodontic repair materials, with its biocompatible nature strongly suggested by its ability to form hydroxyappatite when exposed to physiologic solutions. With some exceptions, MTA materials provide better microleakage protection than traditional endodontic repair materials using dye, fluid filtration, and bacterial penetration leakage models. In both animal and human studies, MTA materials have been shown to have excellent potential as pulp-capping and pulpotomy medicaments but studies with long-term follow-up are limited. Preliminary studies suggested a favorable MTA material use as apical and furcation restorative materials as well as medicaments for apexogenesis and apexification treatments; however, long-term clinical studies are needed in these areas. CONCLUSION: MTA materials have been shown to have a biocompatible nature and have excellent potential in endodontic use. MTA materials are a refined Portland cement material and the substitution of Portland cement for MTA products is presently discouraged. Existing human studies involving MTA materials are very promising, however, insufficient randomized, double-blind clinical studies of sufficient duration exist involving MTA for all of its clinical indications. Further clinical studies are needed in these areas.     

Biocompatibility of two commercial forms of mineral trioxide aggregate

AIM: To examine the biocompatibility of two commercial forms of mineral trioxide aggregate (MTA), by evaluating the morphology of an established cell line. METHODOLOGY: The two cements were cast on glass cover slips and cured for 1 or 28 days. Saos-2 osteosarcoma cells were trypsinized and seeded at a density of 1 x 10(5) cells and were then placed in medium over the material-coated coverslips for 1, 5 and 7 days. After these time intervals the media were discarded and the cells fixed. Cell morphological investigation was performed by scanning electron microscopy at various magnifications ranging from x 250 to x 500. The biocompatibility of cement constituents, alusilicate flux and bismuth oxide was also investigated. RESULTS: All cement samples cured for 1 day showed a confluent cell monolayer after 5 and 7 days. The response to both materials was similar. Materials cured for 28 days showed incomplete cell confluence after 1 and 5 days. Alusilicate flux and bismuth oxide did not demonstrate biocompatibility. CONCLUSIONS: The 1-day cured samples of two commercial forms of MTA showed good biocompatibility. However, the 28-day cured samples were less biocompatible after 1 and 5 days.     

Biocompatibility of retrograde root filling materials: a review

The aim of a retrograde filling material is to fill the apical canal space and to obtain a hermetic seal between the periodontium and the root canal system. Several materials have been suggested for root-end filling including: amalgam, gutta-percha, zinc oxide-eugenol cements, glass ionomer cement, gold foil pellets, Cavit, composite resin and mineral trioxide aggregate (MTA). Super-ethoxy benzoic acid and MTA are the most suitable materials and provide better results in apicoectomy procedures than other filling materials. Unfortunately, the ideal material for this purpose has yet to be found. This article is a review of the biocompatibility of retrograde filling materials.     

Mineral trioxide aggregate for obturation of maxillary central incisors with necrotic pulp and open apices

Abstract – There are few reports on treatment of necrotic pulps with mineral trioxide aggregate (MTA) for apexification. Five immature teeth with necrotic pulps were treated with the use of an apical plug of MTA for apexification. All teeth were central incisors that had premature interruption of root development caused by a previous trauma. According to the treatment protocol, the root canals were rinsed with 5% NaOCl; then calcium hydroxide paste was placed in the canals for 1–6 weeks. The apical portion of the canals were filled with MTA. The rest of the canals were obturated with lateral condensation of the gutta‐percha applied with a canal sealer. At 6 months, 1 year and 2 year follow‐up periods the clinical and radiographic appearance of the teeth showed the resolution of the periapical lesions and continued root end development in all except in the one case in which the MTA was extruded out the apex. MTA can be considered a very effective option for apexification with the advantage of reduced treatment time, good sealing ability and high biocompatibility.     

Effect of root canal irrigation protocols on the dislocation resistance of mineral trioxide aggregate‐based materials: A systematic review of laboratory studies

The aim of this systematic review was to address the question: Do different irrigating protocols have an impact on the dislocation resistance of mineral trioxide aggregate (MTA)‐based materials? The review was performed using a well‐defined search strategy in three databases (PubMed, Scopus, Web of Science) to include laboratory studies performed between January 1995 and May 2017, in accordance with PRISMA guidelines. Two reviewers analysed the papers, assessed the risk of bias and extracted data on teeth used, sample size, size of root canal preparation, type of MTA‐based material, irrigants, canal filling method, storage method and duration, region of roots and the parameters of push‐out testing (slice thickness, plunger dimensions and plunger loading direction), the main results and dislocation resistance values (in MPa). From 255 studies, 27 were included for full‐text analysis. Eight papers that met the inclusion criteria were included in this review. There was a wide variation in dislocation resistance due to differences in irrigation sequence, time and concentration of irrigants, storage method and duration, and the parameters of push‐out bond strength testing. A meta‐analysis was not done but qualitative synthesis of the included studies was performed. No definitive conclusion could be drawn to evaluate the effect of irrigation protocols on dislocation resistance of MTA‐based materials. Recommendations have been provided for standardized testing methods and reporting of future studies, so as to obtain clinically relevant information and to understand the effects of irrigating protocols on root canal sealers and their interactions with the dentine walls of root canals.     

Physicochemical basis of the biologic properties of mineral trioxide aggregate

This study characterized the interactions of mineral trioxide aggregate with a synthetic tissue fluid composed of a neutral phosphate buffer saline solution and root canal dentin in extracted human teeth using inductively coupled plasma-atomic emission spectroscopy, scanning electron microscopy, energy dispersive X-ray analysis, and X-ray diffraction. Mineral trioxide aggregate exposed to synthetic tissue fluid at 37 degrees C released its metallic constituents and produced precipitates with a composition and structure similar to that of hydroxyapatite [Ca10(PO4)6(OH)2-HA]. Endodontically prepared teeth filled with mineral trioxide aggregate and stored in synthetic tissue fluid at 37 degrees C for 2 months produced at the dentin wall an adherent interfacial layer that resembled hydroxyapatite in composition. The authors conclude that Ca, the dominant ion released from mineral trioxide aggregate, reacts with phosphates in synthetic tissue fluid, yielding hydroxyapatite. The dentin-mineral trioxide aggregate interfacial layer results from a similar reaction. The sealing ability, biocompatibility, and dentinogenic activity of mineral trioxide aggregate is attributed to these physicochemical reactions.     

Mineral trioxide aggregate in management of immature teeth with open apices – A report of clinical cases

Injuries to immature permanent teeth due to trauma may eventually result in pulpal necrosis and the subsequent arrest of root development. These teeth are often difficult to treat as the associated open root apex hinders the placement of the root filling material. To overcome this drawback, various materials have been introduced to induce apex closure prior to endodontic treatment. One of the currently popular material for apexification is mineral trioxide aggregate due to its superior biocompatibility, good sealing ability & excellent marginal adaptability. The presented clinical cases justifies the successful nonsurgical management of traumatized upper anterior teeth with mineral trioxide aggregate (MTA).     

三氧化矿物凝聚体的性能及其研究进展

三氧化矿物凝聚体(mineral trioxide aggregate,MTA)是目前牙髓根尖周疾病诊治中采用的一种新式材料。其优良的生物学性能、材料学性能自被人们认识以来便备受推崇,逐步发展为当下口腔常见疾病的治疗中不可或缺的一员。现将其具备的性能及相关研究做一综合论述。     

三氧化矿物聚合物的研究现状

三氧化矿物聚合物(Mineral Trioxide Aggregate, MTA)是近年来出现的一种新型的牙髓病治疗材料,具有无毒性、抗菌性、防渗漏、生物相容性好等诸多优点,现广泛应用于盖髓术、活髓切除术、根管倒充填、穿孔修复、根尖诱导成形术、根尖屏障术等多个方面。自1993年MTA被首次报道后,关于这种材料的各方面得到许多研究。本文就MTA的理化特性、生物学特性和临床应用作一综述。     

Effects of EDTA on the hydration mechanism of mineral trioxide aggregate

Ethylenediaminetetraacetic acid (EDTA) is commonly used during the preparation of obstructed root canals that face a high risk of root perforation. Such perforations may be repaired with mineral trioxide aggregate (MTA). Due to EDTA's ability to chelate calcium ions, we hypothesized that EDTA may disrupt the hydration of MTA. Using scanning electron microscopy and energy-dispersive x-ray spectroscopy, we found that MTA specimens stored in an EDTA solution had no crystalline structure and a Ca/Si molar ratio considerably lower than those obtained for specimens stored in distilled water and normal saline. Poor cell adhesion in EDTA-treated MTA was also noted. X-ray diffraction indicated that the peak corresponding to portlandite, which is normally present in hydrated MTA, was not shown in the EDTA group. The microhardness of EDTA-treated specimens was also significantly reduced (p < 0.0001). These findings suggest that EDTA interferes with the hydration of MTA, resulting in decreased hardness and poor biocompatibility.     

Is there sufficient evidence to support the long‐term efficacy of mineral trioxide aggregate (MTA) for endodontic therapy in primary teeth?

Several papers have been published to illustrate the effectiveness of mineral trioxide aggregate (MTA) as a pulpotomy medicament. Most of these reports do not offer a critical assessment on the data quality. Therefore, this review evaluated whether the currently available evidence is of an appropriate quality to support the long‐term effectiveness of MTA as a pulpotomy medicament in primary molars using a standardized assessment criterion. A comprehensive literature search of human clinical outcome studies, which employed MTA as a pulpotomy medicament in primary teeth, was conducted using the MEDLINE database. Two independent observers rated these articles using the standardized assessment criteria. Furthermore, based on the initial sample mentioned in the individual studies and the sample included for the final analysis, the drop‐out rates were calculated. Twenty‐two studies were included for quality assessment with an excellent interobserver agreement. None of the 22 studies obtained grade A, four studies attained grade B1, five were graded B2 and 13 received grade C. Based on the assessment criteria employed, there was no evidence that MTA was better than present materials and techniques as a pulpotomy medicament. Furthermore, given the low quality of data, it is highly desirable to establish standard requisites for conducting and reporting on pulp therapy studies in primary teeth so as to benefit both researchers and clinicians to produce high‐quality studies that are comparable and to prevent the misuse of clinical material and resources.     

Enhancing Effect of Elastinlike Polypeptide-based Matrix on the Physical Properties of Mineral Trioxide Aggregate

Introduction

Elastinlike polypeptide (ELP) is 1 of the genetically engineered, protein-based polypeptides, which offers outstanding advantages such as superior biocompatibility, long-term stability, elasticity, and cost-effectiveness. This study aimed to investigate the effect of an ELP-based matrix on the physical properties and biocompatibility of mineral trioxide aggregate (MTA).

Effects of intracoronal bleaching agents on the surface properties of mineral trioxide aggregate

Odontology - Bleaching agents may affect surface properties of mineral trioxide aggregate (MTA) as a coronal barrier. The purpose of this study was to investigate surface properties of MTA after...     

新型快速硬固型根尖倒充填材料的研究进展

三氧化矿物聚合物(mineral trioxide aggregate,MTA)是目前临床上常用的根尖倒充填材料,不仅具有良好的生物相容性和封闭性,而且具有很好的抗菌和成骨效果。然而MTA存在着硬固时间长和操作性差的缺点。近年来,为缩短MTA的硬固时间,一些新型快速硬固型硅酸钙基根尖倒充填材料相继出现,该文将对这一类新型材料的种类和研究进展作一综述。     

X-ray diffraction analysis of mineral trioxide aggregate and Portland cement

AIM: To compare the major constituents present in ProRoot mineral trioxide aggregate (MTA), ProRoot MTA (tooth coloured formula), ordinary Portland cement and white Portland cement using powder X-ray diffractometery. METHODOLOGY: X-ray diffractometery of the four materials was carried out with the divergence and scatter slits set at 1 degree and the receiving slit at 0.10 mm. The scan range was set at 5-70 degrees and continuous scans for the theta-2theta range were run with a scan speed of 2 degrees min(-1). The patterns obtained were then compared with the Powder Diffraction Files (PDF) found in the International Centre for Diffraction Data database. The three strongest peaks were used for the identification of the constituents. The relative intensities were plotted against the angle 2theta and compared with the plots in the PDF. RESULTS: The main constituents were found to be tricalcium silicate, tricalcium aluminate, calcium silicate, and tetracalcium aluminoferrite in all the four cements with the additional presence of Bi2O3 in ProRoot MTA and ProRoot MTA (tooth coloured formula). CONCLUSIONS: The four cements had similar major constituents. Data on Portland cement may be used for the further development or modification of ProRoot MTA in order to improve its physical characteristics and expand its scope of clinical applications.     

The chemical constitution and biocompatibility of accelerated Portland cement for endodontic use

AIM: To evaluate the biocompatibility of mineral trioxide aggregate and accelerated Portland cement and their eluants by assessing cell metabolic function and proliferation. METHODOLOGY: The chemical constitution of grey and white Portland cement, grey and white mineral trioxide aggregate (MTA) and accelerated Portland cement produced by excluding gypsum from the manufacturing process (Aalborg White) was determined using both energy dispersive analysis with X-ray and X-ray diffraction analysis. Biocompatibility of the materials was assessed using a direct test method where cell proliferation was measured quantitatively using Alamar Blue dye and an indirect test method where cells were grown on material elutions and cell proliferation was assessed using methyltetrazolium assay as recommended by the International standard guidelines, ISO 10993-Part 5 for in vitro testing. RESULTS: The chemical constitution of all the materials tested was similar. Indirect studies of the eluants showed an increase in cell activity after 24 h compared with the control in culture medium (P<0.05). Direct cell contact with the cements resulted in a fall in cell viability for all time points studied (P<0.001). CONCLUSIONS: Biocompatibility testing of the cement eluants showed the presence of no toxic leachables from the grey or white MTA, and that the addition of bismuth oxide to the accelerated Portland cement did not interfere with biocompatibility. The new accelerated Portland cement showed similar results. Cell growth was poor when seeded in direct contact with the test cements. However, the elution made up of calcium hydroxide produced during the hydration reaction was shown to induce cell proliferation.