Physico-Chemical comparison of four commercially available mineral trioxide aggregates / Comparación fisicoquímica de cuatro mineral trióxido agregados disponibles comercialmente

Abstract To compare the physicochemical composition of 4 MTAs commercially available in Latin America. ProRoot MTA (Dentsply, USA), MTA Angelus (Angelus, Brazil), MTA Flow (Ultradent, USA), and MTA Viarden (Viarden, Mexico) were physically and chemically compared. Scanning electron microscopy (SEM) images were obtained from the MTA powder and the prepared presentations. Energy Dispersive X-Ray Spectroscopy (EDS) analyses were performed by triplicate, to calculate the mass proportion of calcium (Ca), silicon (Si), the Ca/Si proportion among the 4 brands. Thermogravimetric analyses (TGA) were conducted (50ºC-1000ºC), and mass loss and inflection points were calculated for each material. Statistical differences for Ca and Si content were determined by ANOVA (p<0.05). SEM images showed evident differences in the appearance of both the powder and the prepared MTAs among brands. Angelus MTA showed cubic prisms not observed in the other 3 brands. ProRoot MTA and MTA Flow showed similar homogeneous structures. MTA Viarden was the less homogeneous, with random structures (>15um). When comparing the mass proportions of Ca and Si between the 4 powder samples, MTA Viarden showed a significantly lower proportions of both elements when compared with the other brands (p<0.005). TGA análisis showed a similar behavior for ProRoot MTA, MTA Angelus and MTA Flow, with less than 2% mass loss when the 1000C temperature was reached. MTA Viarden showed a mass loss of 9,94% before the 700C, indicating the presence of different content sensible to temperature degradation. The analyzed MTAs demonstrated to vary significantly in their chemical composition and physical characteristics. Clinicians must be aware of the differences between different brands of a same material, and future research should focus on the clinical implications of these differences.

Resumen Comparar la composición fisicoquímica de 4 MTA disponibles comercialmente en América Latina. Se compararon física y químicamente ProRoot MTA (Dentsply, EE. UU.), MTA Angelus (Angelus, Brasil), MTA Flow (Ultradent, EE. UU.) y MTA Viarden (Viarden, México). Se obtuvieron imágenes de microscopía electrónica de barrido (SEM) del polvo de MTA y de las presentaciones preparadas. Los análisis de espectroscopía de dispersión de energía de rayos X (EDS) se realizaron por triplicado para calcular la proporción de masa de calcio (Ca), silicio (Si), la proporción Ca/Si entre las 4 marcas. Se realizaron análisis termogravimétricos (TGA) (50ºC-1000ºC), y se calcularon las pérdidas de masa y los puntos de inflexión para cada material. Las diferencias estadísticas para el contenido de Ca y Si se determinaron mediante ANOVA (p<0,05). Los análisis SEM mostraron diferencias evidentes en la apariencia tanto del polvo como las preparaciones de los MTA, entre las diferentes marcas. MTA Angelus mostró prismas cúbicos no observados en las otras 3 marcas. ProRoot MTA y MTA Flow mostraron estructuras homogéneas similares. MTA Viarden fue el menos homogéneo, con estructuras aleatorias (>15um). Al comparar las proporciones de masa de Ca y Si entre las 4 muestras de polvo, MTA Viarden mostró proporciones significativamente más bajas de ambos elementos en comparación con las otras marcas (p<0,005). El análisis TGA mostró un comportamiento similar para ProRoot MTA, MTA Angelus y MTA Flow, con menos del 2 % de pérdida de masa al alcanzar los 1000 °C de temperatura. El MTA Viarden mostró una pérdida de masa de 9,94% antes de los 700 °C, indicando la presencia de diferentes contenidos sensibles a la degradación por temperatura. Los MTA analizados demostraron diferencias significativas en su composición química y características físicas. Los clínicos deben ser conscientes de las diferencias entre las diferentes marcas de un mismo material, y futuras investigaciones deben enfocarse en las implicaciones clínicas de estas diferencias.

Eficacia Antimicrobiana del Cemento Portland Comparado con el Mineral Trióxido Agregado Frente a Enterococcus faecalis y Candida albicans

RESUMEN: El objetivo del estudio experimental in vitro fue evaluar la eficacia antimicrobiana del cemento Portland (CP) comparado con el Mineral Trióxido Agregado (MTA) frente a cepas de Enterococcus faecalis (E. faecalis) y Candida albicans (C. albicans) a las 24, 48 y 72 horas después del sembrado. Para ello se utilizó la técnica de difusión en agar. La capa base fue realizada con el Agar Müller-Hinton en el que se hicieron agujeros de 6 mm de diámetro a fin de contener los cementos de estudio y medir posteriormente la zona de inhibición microbiana alrededor de los materiales mediante un calibrador vernier digital. Se utilizó la prueba T de Student para comparar la diferencia entre el CP y MTA y el análisis de ANOVA para evaluar las diferencias entre los tres tiempos de estudio. Los resultados mostraron que tanto frente a E. faecalis y C. albicans el CP tuvo un mayor halo de inhibición que el MTA, siendo estas diferencias estadísticamente significativas (p0.05). Asimismo, la C. albicans presentó valores mayores de inhibición que el E. faecalis en los dos cementos estudiados. Se concluyó que el CP tuvo mayor eficacia antimicrobiana que el MTA independientemente del tiempo evaluado.

ABSTRACT: The aim of the experimental in vitro study was to evaluate the antimicrobial efficacy of Portland cement (CP) compared with Mineral Trioxide Aggregate (MTA) against Enterococcus faecalis (E. faecalis) and Candida albicans (C. albicans) strains at 24, 48 and 72 hours after sowing. For this, the agar diffusion technique was used. The base layer was made with Müller-Hinton Agar in which 6 mm diameter holes were made in order to contain the study cements and subsequently measure the zone of microbial inhibition around the materials using a digital vernier caliper. The Student's t test was used to compare the difference between CP and MTA and the ANOVA analysis to evaluate the differences between the three study times. The results showed that both against E. faecalis and C. albicans, CP had a greater inhibition than MTA, these differences being statistically significant (p 0.05). Likewise, C. albicans presented higher inhibition values than E. faecalis in the two cements studied. It was concluded that CP had greater antimicrobial efficacy than MTA regardless of the time evaluated.

Endodontic sealers and post-endodontic waiting time affect the bond strength of the fiber posts / Cimentos endodônticos e tempo de espera após endodontia afeta a resistência de união de pinos de fibra

Introduction: The resistance adhesive of a fiber post can be affected by several factors, such as the endodontic sealer and post-endodontic waiting time. Objective: The aim of this study was to evaluate the effect of different endodontic sealers and two different post-endodontic waiting times on the bond strength of fiber posts. Material and method: Seventy-two bovine teeth were endodontically treated and filled using three endodontic sealers: eugenol-based, epoxy resin-based, or mineral trioxide aggregate-based. The specimens were stored at 37°C for 24 hours or for 30 months. After the respective storage times, the root canals were prepared for luting fiber posts using RelyX U200. Push-out tests and analysis of failures were performed. The push-out data were analyzed by two-way analysis of variance to compare the effects of the endodontic sealer and with the t-test to compare the effects of post-endodontic waiting time. Result: The AH Plus sealer yielded the highest bond strength values at 30 months post-endodontics (11.26 Mpa) (p < 0.05), however no had difference with Endofill sealer at the same time. Endofill and MTA Fillapex sealers did not differ significantly in their effects, irrespective of the post-endodontic waiting time. Conclusion: In conclusion, the endodontic sealer used and post-endodontic waiting time affect the adhesive resistance of fiber posts. The adhesion increases significantly when the fiber post is cemented 30 months after the root canal filling, while the adhesion is reduced when cementing immediately after root canal treatment, in particular for eugenol-based endodontic sealers.

Introdução: A resistência de união de um pino de fibra pode ser afetada por vários fatores, como o cimento endodôntico e o tempo de espera pós-endodontia. Objetivo: Avaliar o efeito de diferentes cimentos endodônticos e dois tempos de espera pós-endodontia na resistência de união de pinos de fibra. Material e método: Setenta e dois dentes bovinos foram tratados endodonticamente e obturados usando três cimentos endodônticos: à base de eugenol, à base de resina epóxia ou à base de mineral trióxido agregado. Os espécimes foram armazenados a 37 ° C por 24 horas ou por 30 meses. Após, os canais radiculares foram preparados para cimentação dos pinos de fibra usando o RelyX U200. Foram realizados testes de push-out e análise de falhas. Os dados foram analisados por análise de variância bidirecional e com o teste t. Resultado: O cimento AH Plus obteve os maiores valores de resistência de união aos 30 meses pós-endodontia (11,26 Mpa) (p <0,05), no entanto, não houve diferença com o cimento Endofill no mesmo tempo. Os cimentos Endofill e MTA Fillapex não diferiram significativamente em seus efeitos, independentemente do tempo de espera pós-endodontia. Conclusão: O cimento endodôntico utilizado e o tempo de espera pós-endodontia afetam a resistência adesiva dos pinos de fibra. A adesão aumenta significativamente quando o pino de fibra é cimentado 30 meses após a obturação do canal radicular, enquanto a adesão é reduzida ao cimentar imediatamente após o tratamento do canal radicular, principalmente para cimentos endodônticos à base de eugenol.

Efecto osteoinductor del mineral trióxido agregado versus el cemento Portland tipo I sobre lesiones óseas mandibulares

Introducción: Estudio experimental donde se procuró determinar el efecto osteoinductor del mineral trióxido agregado (MTA) versus el cemento Portland tipo I sobre lesiones óseas mandibulares. Metodología: Se emplearon 12 conejos machos de la raza New Zealand de 3 meses de edad, los cuales fueron divididos en 4 grupos iguales. Todos los conejos fueron anestesiados utilizando pentobarbital sódico. Se procedió a la incisión en la piel mandibular para exponer el hueso sobre el que se realizó 3 cavidades de 3mm cada una. En una cavidad se colocó MTA, en otra cemento Portland y en la tercena ninguna pasta. Se procedió al sacrificio de los grupos experimentales a la 1era, 2da, 3era y 4ta semana respectiva y se evaluó las muestras obtenidas de las áreas quirúrgicas mediante conteo de osteocitos y osteoblastos. Resultados: Tanto el MTA como el cemento Portland poseen la misma capacidad osteoinductiva en la 1era, 2da y 3era semana (p>0,05). Sin embargo, en la 4ta semana el MTA tuvo mayor capacidad osteoinductora al estimular mayor número de osteoblastos que el cemento Portland (p=0,024). Conclusiones: El MTA y el cemento Portland tipo I mostraron similar efecto osteoinductor durante las 3 primeras semanas de evaluación. El MTA demostró mayor efecto osteoinductor durante la cuarta semana de valoración.

Introduction: An experimental study was carried out to determine the osteoinductive effect of Mineral Trioxide Aggregate (MTA) versus Portland Cement type I on mandibular bone lesions. Methodology: Twelve 3-month-old male New Zealand rabbits were divided into 4 equal groups. All rabbits were anesthetized using Pentobarbital. An incision of the mandibular skin was performed to expose the bone on which 3 cavities of 2mm each one were made. In one cavity MTA was placed, in another Portland Cement type I and the third remained empty. The experimental groups were sacrificed at the 1st, 2nd, 3rd and 4th respective weeks and evaluated histologically by counting osteocytes and osteoblasts. Results: Both MTA and Portland cement have the same osteoinductive capacity in the 1st, 2nd and 3rd week (0.05

Análise físico-química do MTA e do cimento Portland associado a quatro diferentes radiopacificadores / Physicochemical analysis of MTA and Portland cement associated with four different radiopacifiers

Introdução: O Mineral Trióxido Agregado (MTA) é composto por cimento Portland (CP) e um radiopacificador (óxido de bismuto). Objetivo: Avaliar tempo de presa, solubilidade, pH, liberação de íons Cálcio e radiopacidade do cimento Portland puro ou associado a quatro radiopacificadores (sulfato de bário, carbonato de bismuto, óxido de bismuto e iodofórmio), comparados ao MTA branco (Angelus, Londrina, Brasil). Material e Método: A proporção empregada CP/radiopacificador foi de 4:1 em peso, (80% de cimento Portland e 20% de radiopacificador). A especificação 57 da ADA foi usada para avaliação do tempo de presa. A solubilidade foi analisada segundo a especificação ISO 6876/2001. A avaliação do pH foi realizada com peagâmetro digital e a liberação de íons Ca++foi verificada por meio de espectrofotômetro de absorção atômica. A radiopacidade foi determinada em milímetros de alumínio (mm/Al). Os resultados foram submetidos aos testes de Análise de Variância e Tukey, nível de significância 5%. Resultado: O sulfato de bário não alterou o tempo de presa final do CP. Radiopacidade inferior ao mínimo recomendado pelas normas da ADA nº 57 e ISO 6876/2001 foi observada para CP e CP associado com sulfato de bário. O CP associado ao iodofórmio apresentou solubilidade acima dos 3% recomendados pela ISO 6876/2001. Todos os materiais proporcionaram alcalinização do meio e promoveram liberação de íons cálcio. Conclusão: Carbonato de bismuto ou óxido de bismuto proporcionaram tempo de presa inicial, solubilidade, pH, liberação de íons Cálcio e radiopacidade adequados quando associados ao CP. .

Introduction: Mineral Trioxide Aggregate (MTA) is composed of Portland cement (PC), and a radiopacifier (bismuth oxide). Objective: To evaluate the setting time, solubility, pH, calcium ion release and radiopacity of pure Portland cement and its association to four radiopacifiers, (Barium sulfate, bismuth carbonate, bismuth oxide and iodoform), and White MTA (Angelus, Londrina, Brazil). Material and Method: The ratio CP/radiopacifier used was 4:1 by weight (80% Portland cement and 20% radiopacifier). The setting time was evaluated according the specification ADA 57. The solubility was analyzed according to ISO 6876/2001 specification. The pH was evaluated using a digital pHmeter and the release of Ca++ ions by atomic absorption spectrophotometer. The radiopacity was measured in millimeters of aluminum (mm/Al). The results were submitted to ANOVA and Tukey tests using 5% of significance level. Result: Barium sulfate did not alter the final setting time of the PC. Observed radiopacity was less than the minimum recommended by ADA 57 and ISO 6876/2001 for CP and CP associated with barium sulfate. The PC associated with iodoform showed solubility above the 3% recommended by ISO 6876/2001. All materials provided alkalinization and promoted calcium ion release. Conclusion: Bismuth carbonate and bismuth oxide provided proper initial setting time, solubility, pH, calcium ion release and radiopacity when combined with CP. .

El hidróxido de calcio, como paradigma clínico, es superado por el agregado de trióxido mineral (MTA) / Calcium hidroxide as a clinical paradigm is surpassed by mineral trioxide aggregate (MTA)

Introducción: desde la investigación científica, el hidróxido de calcio (HC) se posicionó por varias décadas, como una elección con alta posibilidad predictiva en la terapia pulpar. Hoy en día, estamos frente a la ruptura de este paradigma, debido a que ha surgido el mineral trióxido agregado (MTA), con sus características de biocompatibilidad, habilidad para estimular la mineralización, poder antimicrobiano y otras que lo hacen más exitoso en la terapia endodóncica. El objetivo de esta revisión fue identificar los usos del HC y del MTA, desde 1995 hasta el presente, en diferentes condiciones clínicas odontológicas. Métodos: se hizo una búsqueda detallada de la literatura en las bases de datos Medline, PubMed y SciELO, desde 1995 hasta el presente. Se revisaron los títulos, resúmenes, artículos completos, revisiones sistemáticas, y meta análisis, relacionadas con el HC y el MTA. Resultados: basados en investigaciones científicas, muchos son los estudios que destacan las propiedades del HC en la terapia pulpar; sin embargo, se ha venido utilizando y estudiando el MTA, como material de reemplazo. Conclusiones: con el MTA, estamos frente a un material, que según los resultados de las investigaciones, puede emplearse en las mismas situaciones indicadas para el uso del HC, con una mejor predecibilidad de éxito.

Introduction: as a result of scientific research, calcium hydroxide (CH) enjoyed a privileged position for several decades as a choice with high predictive abilities for pulp therapy. We are now witnessing the collapse of this paradigm due to the emergence of mineral trioxide aggregate (MTA) with its biocompatibility—an ability to stimulate mineralization—, antimicrobial properties, and other advantages that make it more successful in endodontic therapy. The objective of this topic review was to identify the uses of CH and MTA from 1995 to the present, in different clinical conditions. Methods: this review consisted of a comprehensive literature search in Medline, PubMed, and SciELO from 1995 to the present. It included titles, abstracts, full articles, systematic reviews, and meta-analysis related to CH and MTA. Results: a number of scientific studies highlight the properties of CH in pulp therapy; however, MTA has also been used and studied as a replacement material. Conclusions: according to research on this field, MTA can be used in the same situations for which CH is recommended, with better probabilities of success.

Eficacia de la obturación ortógrada de conductos radiculares con MTA vs. MTA más conos de gutapercha / Orthograde root canal obturation efficacy of MTA vs. MTA with gutta percha points

Objetivo: Evaluar la capacidad del sellado del MTA usado como material único de sellado o usándolo como cemento sellador más conos de gutapercha. Materiales y métodos: Se seleccionaron las raíces mesiales de 24 molares inferiores y se instrumentaron hasta una lima maestra apical # 40 con la técnica de Crown Down. El grupo I fue obturado con conos de gutapercha y el MTA fue usado como cemento sellador; el grupo II fue obturado con MTA solamente. Se utilizaron cuatro raíces como control positivo y negativo; las muestras fueron cubiertas con cera pegajosa, dejando libre solo los dos últimos milímetros apicales, se centrifugaron en tinta china durante una hora y se les realizó procedimiento de transparentación, para posteriormente medir la microfiltración con un microscopio estereoscópico. Resultados: Los resultados fueron analizados estadísticamente con el test de KRUSKAL-WALLIS para variables independientes, y no se encontró diferencia estadísticamente significativa entre los dos grupos. Conclusiones: No se encontró diferencia estadísticamente significativa entre los dos grupos. En situaciones clínicas que no permiten la obturación convencional con conos de gutapercha, cualquiera de las dos técnicas de colocación del MTA son factibles.

Objetives: This study evaluated the sealing capability of MTA when it is used as the only root canal filling material and when it is used as sealing cement combined with gutapercha points. Materials and methods: The mesial roots of 24 inferior molars were selected; they were instrumented until an apical master file # 40 with Crown Down technique. Group I were obtured with gutapercha points and MTA as sealing cement; group II were obtured only with MTA. Four roots were used as positive and negative control, samples were covered with sticky wax, leaving free the apical last 2 mm, they were centrifugued with chinese ink for one hour and then they were turned transparent, to measure the microleakage with a stereoscopic microscope. Results: Results were analyzed statistically with the KRUSKAL-WALLIS test for independent variables and statistically no significant difference was found between the two groups. Conclusion: Statistically no significant difference was found between the two groups. In such clinical situations that don't permit conventional obturation with gutapercha points, both MTA techniques are viable.

Comparative study of physico-chemical properties of MTA-based and portland cements

The purpose of this investigation was to evaluate the physicochemical properties of gray and white structural and nonstructural Portland cement, gray and white ProRoot MTA and MTA BIO. The water/powder ratio, setting time, solubility and pH (hydrogen-ion potential) changes of the materials were evaluated. Tests followed specification #57 from the American National Standard Institute/ American Dental Association (2000) for endodontic sealing materials and pH was determined by a digital pHmeter. The test results were statistically analyzed by variance analyses for global comparison and by the complementary Tukey's test for pairwise comparisons (5%). Considering the water/powder ratio, no significant difference (p>0.05) was observed among the cements. MTA BIO (33.10±2.30) had the lowest setting time (p<0.05), gray Pro- Root MTA (10.10±2.70) had the highest (p<0.05). White nonstructural Portland cement (2.55±0.08) had the highest solubility (p<0.05), while gray ProRoot MTA (1.03±0.12) had the lowest (p<0.05), although all materials showed solubility values in compliance to ANSI/ADA. No difference (p>0.05) was observed among materials when considering pH evaluation. The pH levels were highly alkaline immediately after immersion in solution, remaining stable throughout the test period. The authors conclude that the cements had similar water/powder proportions. MTA BIO had the shortest setting time and gray ProRoot MTA had the lowest solubility. All cements had similar behavior in the pH analysis.

A proposta desse trabalho foi de avaliar as propriedades fisicoquimicas dos cimentos Portland cinza e branco estrutural e nao estrutural, do ProRoot MTA cinza e branco e do MTA BIO. Foram avaliadas a proporcao po-liquido, tempo de endurecimento, solubilidade e variacao do pH dos cimentos. Os testes seguiram as normas que determinam a especificacao numero 57 da ANSI/ ADA para cimentos obturadores e a variacao de pH foi analisada por meio de pHmetro digital. Os resultados dos testes foram analisados estatisticamente por meio de teste de analise de variancia e pelo teste de Tukey para comparacao entre pares, com nivel de significancia de 5%. Nao foram evidenciaram diferencas estatisticamente significantes (p>0,05) entre os cimentos no que se refere a proporcao po-liquido. O MTA BIO (33,10±2,30) mostrou os menores valores de tempo de endurecimento (p<0,05), enquanto o ProRoot MTA cinza (102,10±2,70) mostrou os maiores resultados (p<0,05). Todos os materiais mostraram valores de solubilidade dentro dos padroes da ANSI/ADA, sendo que o cimento ProRoot MTA cinza (1,03±0,12) apresentou a menor solubilidade (p<0,05) e o Portland branco nao estrutural (2,55±0,08), a maior (p<0,05). No que se refere a variacao do pH, nao foram determinadas diferencas significantes entre os materiais (p>0,05). Os niveis de pH mostraram-se altamente alcalinos, imediatamente apos a imersao em agua, mantendo-se estavel ao longo do periodo de teste. Concluiu-se, que os cimentos estudados tiveram proporcoes po-liquido similares. O MTA BIO apresentou tempo de endurecimento mais curto e a menor solubilidade foi apresentada pelo ProRoot MTA cinza. Todos os cimentos tiveram comportamento semelhante na analise do pH.

Avaliação Clínica e Radiográfica do emprego do Mineral Trióxido Agregado (MTA) em dentes decíduos pulpotomizados / Evaluation Clinical and Radiografic of the use Mineral Aggregate Trioxide (MTA) in pulpotomizados deciduous teeth

A pulpotomia tem como princípio básico a remoção total da polpa coronária e subsequente dos filetes remanescentes radiculares, em condições de saúde, permitindo que o ciclo biológico do dente decíduo prossiga naturalmente. Muitos são os materiais de escolha para realização desse procedimento. Desta forma, foram selecionados 30 molares decíduos em pacientes atendidos em clínica de Odontopediatria durante o ano de 2006, com indicação clínica e radiográfica para a realização de pulpotomia, utilizando-se o Mineral Trióxido Agregado (MTA) como material de escolha. Após o procedimento fi realizada proservação clínica e radiográfica, com intervalo de 90 a 180 dias, para observar o selamento marginal da câmara pulpar, bem como a preservação das estruturas periodontais e possívelformação de barreira dentinária (ponte de dentina),. Os resultados comprovaram que o MTA pode ser utilizado como material de escolha por ser biocompatível.

The pulpotomy basic principle is the total removal of the coronary pulp and subsequent remaining of pulpa radicularis, in healh conditions, allowin the biological cycle of the primary tooth to continue of course.Formocresol, during much time, has been the material of choice to accomplish this procedure. Of this from, 30 molars deciduos were selected from patients being taken care of during the Course in Pedodontist in the uear of 2006, with clinical and radiographic indication for pulpotomy accomplishment using Mineral Trioxide Aggregate (MTA) as the material of choice. After the procedure had been carriedthough clinical and radiographic accessory in an interval pf 90 and 180 days, to observe the sealing marginal of the chamber pulp, as well as the preservation of the periodontals structures. The results prove that the MTA is a biocompatible material.