Clinical Management of Intra-Pulp Canal Broken Endodontic Files in Primary Teeth: Literature Review / Manejo clínico de las limas endodónticas fracturadas dentro del conducto pulpar en dientes primarios: Revisión de la literatura

ABSTRACT: Fracture of an endodontic file inside a primary root canal is a rare but critical complication during the pulpectomy treatment, because the mechanical obstruction impedes the optimal cleaning and obturation of the pulp canal, compromising seriously the clinical outcome. This accidental event is mainly associated with over-use and excessive torque of intracanal files. Most clinicians opt to proceed with the extraction of the affected tooth followed by a space maintainer placement. Other practitioners attempt the non-surgical retrieval of the separated fragment through available proven techniques in permanent teeth; however, these methods may involve significant damage to the tooth and surround tissues. On the other hand, preservation of the metallic fragment might affect the treatment prognosis and interfere with the physiological root resorption.

RESUMEN: La fractura de una lima endodóntica dentro de un conducto radicular primario es una complicación rara aunque critica durante el tratamiento de pulpectomía, debido a que la obstrucción mecánica impide la limpieza y obturación óptimas del conducto pulpar, comprometiendo seriamente el resultado clínico. Este evento accidental está principalmente asociado con el sobreuso y torque excesivo de las limas dentro del conducto. La mayoría de los clínicos optan por realizar la extracción del diente afectado, seguido por la colocación de un mantenedor de espacio. Otros practicantes intentan la remoción no quirúrgica del fragmento separado a través de técnicas disponibles probadas en dientes permanentes; sin embargo, estos métodos pueden causar daños significativos al diente y tejidos circundantes. Por otra parte, la preservación del fragmento metálico puede afectar el pronóstico del tratamiento e interferir con el proceso de reabsorción radicular fisiológico.

Recubrimiento directo con agregado trióxido mineral (MTA) comparado con hidróxido de calcio para caries dentinaria profunda en pacientes con dentición permanente / Direct pulp capping using mineral trioxide aggregate (MTA) versus calcium hydroxide for deep dental caries in permanent dentition

RESUMEN: Introducción: El recubrimiento pulpar directo es un método para tratar la pulpa vital expuesta conservando su vitalidad. Tradicionalmente se ha utilizado el hidróxido de calcio como material de elección para este tratamiento, sin embargo, sus efectos adversos han promovido el desarrollo y utilización de agregado trióxido mineral (MTA), del cual aún existe controversia sobre una mayor efectividad. Métodos: Realizamos una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, analizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. Resultados y conclusiones: Identificamos cuatro revisiones sistemáticas que en conjunto incluyeron siete estudios primarios, de los cuales, cuatro corresponden a ensayos aleatorizados. Concluimos que el recubrimiento directo con agregado trióxido mineral (MTA) comparado con hidróxido de calcio probablemente aumenta el éxito clínico y que podría aumentar la sobrevida pulpar, pero la certeza de la evidencia es baja.

ABSTRACT: Introduction: Direct pulp capping has been suggested as the treatment of exposed vital pulp. Conventionally calcium hydroxide (CH) has been the main biomaterial option for maintaining pulp vitality, but its adverse effects have promoted the development and use of mineral trioxide aggregate (MTA). However, there is still uncertainty regarding its effectiveness. Methods: We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. Results and conclusions: We identified four systematic reviews including seven studies overall, of which four were randomized trials. We conclude that direct pulp capping with mineral trioxide aggregate (MTA) probably improves clinical success rate and may improve pulp survival rate, however, the certainty of the evidence has been assessed as low.

Effect of preheating on cytotoxicity and physicochemical properties of light-cured calcium-based cements / Efeito do pré-aquecimento na citotoxicidade e propriedades físico-químicas de cimentos à base de cálcio fotopolimerizáveis

ABSTRACT The aim of this study was to evaluate the degree of conversion, cytotoxicity, solubility and pH of photopolymerizable calciumbased cements submitted to preheating. The degree of conversion was analyzed by Fourier transform infrared, cytotoxicity by the MTT test and solubility through loss of mass. The data were subjected to statistical tests (ANOVA / Tukey's, p<0.05). The photopolymerizable materials showed a low degree of conversion, regardless of preheating. All materials caused a reduction in cell viability at 24 hours and 7 days, with the Dycal (control) being more cytotoxic. Heat had a positive effect on Biocal at 7 days. Dycal is the most soluble material. Heat had no effect on the solubility or pH of the polymerizable materials. It is concluded that photopolymerizable calcium-based cements have a low degree of conversion and are soluble, which results in mild to moderate cytotoxicity.

RESUMO O objetivo do presente estudo foi avaliar o grau de conversão, citotoxicidade, solubilidade e pH de cimentos à base de cálcio fotopolimerizáveis submetidos a pré-aquecimento. O grau de conversão foi analisado por espectroscopia no infravermelho com transformada de Fourier, a citotoxicidade pelo teste de MTT e a solubilidade através da perda de massa. Os dados foram submetidos a testes estatísticos (ANOVA/Tukey, p<0,05). Os materiais fotopolimerizáveis apresentaram baixo grau de conversão, independente do pré-aquecimento. Todos os materiais causaram redução da viabilidade celular nas análises de 24 horas e 7 dias, sendo que o Dycal (controle) apresentouse mais citotóxico e o calor apresentou efeito positivo sobre o Biocal na análise de 7 dias. O Dycal é o material mais solúvel e o calor não causou efeito na solubilidade e pH dos materiais polimerizáveis. Assim, conclui-se que os cimentos à base de cálcio fotopolimerizáveis apresentam baixo grau de conversão e são solúveis, que resulta em citotoxicidade suave e moderada.

Physical-mechanical properties of a resin-modified calcium silicate material for pulp capping

Abstract The purpose of this study was to investigate and to compare the physical-mechanical properties of a resin-modified calcium silicate material (TheraCal LC), used for pulp-capping, to MTA (Angelus) and a calcium hydroxide cement (Dycal). Specimens of each material (n=12) were prepared in Teflon molds (3.58 mm x 3 mm) and measured before and after immersion in distilled water for 24 h and 30 days to evaluate the dimensional change. The same specimens were submitted to compressive strength test on a Universal Testing Machine (Instron) (1 mm/min). Root canals were filled with the cements (n=8), and after 24 h, the bond strength (push-out test) to dentin was also assessed on a Universal Testing Machine (1 mm/min). Eight additional specimens of TheraCal LC were prepared to evaluate the bond strength immediately after light curing. Data were analyzed using One-Way ANOVA, and Tukey or Bonferroni post hoc tests (p<0.05). Percentage expansion of TheraCal LC was above the Specification No. 57 of ANSI/ADA, in both periods. The dimensional change for TheraCal LC was higher than MTA in 24 h and 30 days; and Dycal in 30 days (p<0.05). TheraCal LC had higher compressive and bond strength to dentin in comparison with MTA and Dycal (p<0.05). Although TheraCal LC expanded more than the ANSI/ADA recommendation, its compressive and push-out bond strength to dentin were satisfactory and superior to MTA and Dycal.

Resumo O objetivo deste estudo foi investigar e comparar as propriedades físico-mecânicas de um material à base de silicato de cálcio modificado por resina (TheraCal LC) ao MTA (Angelus) e um cimento de hidróxido de cálcio (Dycal). Espécimes de cada material (n=12) foram fabricados em moldes de Teflon (3,58 mm x 3 mm) e medidos antes e após imersão em água destilada por 24 h e 30 dias para avaliar a alteração dimensional. Os mesmos espécimes foram submetidos ao teste de resistência à compressão em uma Máquina Universal de Testes (Instron) (1 mm/min). Canais radiculares foram preenchidos com os cimentos (n=8), e após 24 h, a resistência de união (teste de push-out) também foi avaliada em uma Máquina Universal de Testes (1 mm/min). Oito amostras adicionais de TheraCal LC foram preparadas para avaliar a resistência de união imediatamente após a fotoativação. Os dados foram analisados utilizando os testes ANOVA de 1-fator e Tukey; ou Bonferroni (p<0,05). A expansão percentual do TheraCal LC ficou acima da Especificação No. 57 do ANSI/ADA, em ambos os períodos. Os valores de alteração dimensional para TheraCal LC foram maiores que MTA em 24 h e 30 dias; e Dycal em 30 dias (p<0,05). TheraCal LC apresentou maior resistência à compressão e união à dentina em comparação ao MTA e Dycal (p<0,05). Embora TheraCal LC tenha expandido mais que a recomendação da ANSI/ADA, sua resistência à compressão e de união à dentina foram satisfatórias e superiores ao MTA e Dycal.

Estudo clínico controlado, randomizado, duplo cego de pulpectomias em dentes decíduos obturados com Bio-C Pulpecto e Vitapex / Controlled, randomized, double-blind clinical study of pulpectomy in primary teeth filled with Bio-C Pulpecto and Vitapex

O objetivo deste estudo foi avaliar os aspectos clínicos e radiográficos de pulpectomias realizadas em dentes decíduos e obturadas com cimento à base de silicato de cálcio, Bio-C Pulpecto, em comparação com a pasta Vitapex®. Sessenta e sete dentes decíduos em 46 crianças foram divididos aleatoriamente em dois grupos, grupo Bio-C Pulpecto (n=32 dentes) e grupo Vitapex® (n=35 dentes). Os critérios para sucesso clínico foram: dente apresentar-se livre dos sinais e sintomas como, dor espontânea, mobilidade patológica, edema, abscesso e fístula, avaliados nos tempos de 7 dias, 1, 3, 6 e 12 meses. Os critérios para sucesso radiográfico foram: ausência de reabsorção radicular interna e radioluscência periapical/furcal recém-formada, avaliados aos 1, 3, 6 e 12 meses. Não foram constatadas diferenças estatisticamente significante nos aspectos clínicos investigados, em nenhum dos tempos avaliados. Aos 12 meses, as taxas de sucesso clínico foram de 84,61% no grupo Bio-C Pulpecto e 90,91% no grupo Vitapex®. Em relação ao desfecho secundário de descoloração da coroa dentária, aos 12 meses de controle, no grupo Bio-C Pulpecto, 15,38% (2/13) dos dentes apresentaram descoloração da coroa dentária enquanto que no grupo Vitapex® este achado foi de 31,82% (7/22), porém sem diferença estatisticamente significante entre os grupos (p= 0,431). Após avaliação de imagens radiográficas realizadas aos 12 meses, foi detectada diferença estatisticamente significante na frequência de reabsorção de pasta obturadora no periápice, aos 3 meses (p = 0,044), sendo a maior quantidade de casos de reabsorção identificada no grupo Bio-C Pulpecto (34,78%) em comparação a pasta Vitapex® (10,35%). Conclui-se que tanto nos aspectos clínico quanto no radiográfico, o Bio-C Pulpecto apresentou resultados favoráveis indicando a possibilidade de uso como material obturador para dentes decíduos(AU)

The aim of this study was to evaluate clinical and radiographic aspects of pulpectomy performed on primary teeth and filled with calcium silicate-based cement, Bio-C Pulpecto, in comparison with Vitapex paste. Sixty-seven primary teeth in 46 children were randomly divided into two groups, Bio-C Pulpecto group (n = 32 teeth) and Vitapex group (n = 35 teeth). The criteria for clinical success were: tooth being free of signs and symptoms, such as spontaneous pain, pathological mobility, edema, abscess and fistula, evaluated at 7 days, 1, 3, 6 and 12 months. The criteria for radiographic success were: absence of internal root resorption and newly formed periapical / furcal radiolucency, evaluated at 1, 3, 6 and 12 months. There were no statistically significant differences in the investigated clinical aspects, in any of the evaluated times. At 12 months, the clinical success rate was 84.61% in Bio-C Pulpecto group and 90.91% in Vitapex group. Regarding the outcome of dental crown discoloration, at 12 months of control, in Bio-C Pulpecto group 15.38% (2/13) of the teeth showed discoloration of the dental crown while in Vitapex group this finding was 31.82% (7/22), but there was no statistically significant difference between Bio-C Pulpecto and Vitapex (p = 0.431). After evaluation of radiographic images taken at 12 months, a statistically significant difference was detected in frequency of resorption of in the periapices, at 3 months (p = 0.044), with the largest number of cases of filling paste resorption identified in Bio-C Pulpecto group (34.78%) compared to Vitapex paste (10.35%). It is concluded that both in clinical and radiographic aspects, Bio-C Pulpecto presented favorable results indicating the possibility of use as a filling material for primary teeth(AU)

Evaluation of dentinogenesis inducer biomaterials: an in vivo study

Abstract When exposure of the pulp to external environment occurs, reparative dentinogenesis can be induced by direct pulp capping to maintain pulp tissue vitality and function. These clinical situations require the use of materials that induce dentin repair and, subsequently, formation of a mineralized tissue. Objective: This work aims to assess the effect of tricalcium silicate cements and mineral trioxide aggregate cements, including repairing dentin formation and inflammatory reactions over time after pulp exposure in Wistar rats. Methodology: These two biomaterials were compared with positive control groups (open cavity with pulp tissue exposure) and negative control groups (no intervention). The evaluations were performed in three stages; three, seven and twenty-one days, and consisted of an imaging (nuclear medicine) and histological evaluation (H&E staining, immunohistochemistry and Alizarin Red S). Results: The therapeutic effect of these biomaterials was confirmed. Nuclear medicine evaluation demonstrated that the uptake of 99mTc-Hydroxymethylene diphosphonate (HMDP) showed no significant differences between the different experimental groups and the control, revealing the non-occurrence of differences in the phosphocalcium metabolism. The histological study demonstrated that in mineral trioxide aggregate therapies, the presence of moderate inflammatory infiltration was found after three days, decreasing during follow-ups. The formation of mineralized tissue was only verified at 21 days of follow-up. The tricalcium silicate therapies demonstrated the presence of a slight inflammatory infiltration on the third day, increasing throughout the follow-up. The formation of mineralized tissue was observed in the seventh follow-up day, increasing over time. Conclusions: The mineral trioxide aggregate (WhiteProRoot®MTA) and tricalcium silicate (Biodentine™) present slight and reversible inflammatory signs in the pulp tissue, with the formation of mineralized tissue. However, the exacerbated induction of mineralized tissue formation with the tricalcium silicate biomaterial may lead to the formation of pulp calcifications

Comparison of the Microleakage and Shear Bond Strength to Dentine of Different Tricalcium Silicate-based Pulp Capping Materials / 대한소아치과학회지

This study evaluated the microleakage of three restorative materials and three tricalcium silicate-based pulp capping agents. The restorative materials were composite resin (CR), resin-reinforced glass ionomer cement (RMGI), and traditional glass ionomer cement (GIC) and the pulp capping agents were TheraCal LC® (TLC), Biodentine® (BD), and ProRoot® white MTA (WMTA). Additionally, shear bond strengths between the pulp-capping agents and dentine were compared.Class V cavities were made in bovine incisors and classified into nine groups according to the type of pulp-capping agent and final restoration. After immersion in 0.5% fuchsin solution, each specimen was observed with a stereoscopic microscope to score microleakage level. The crowns of the bovine incisors were implanted into acrylic resin, cut horizontally, and divided into three groups. TLC, BD and WMTA blocks were applied on dentine, and the shear bond strengths were measured using a universal testing machine.The microleakage was lowest in TLC + GIC, TLC + RMGI, TLC + CR, and BD + GIC groups and highest in WMTA + RMGI and WMTA + CR groups. The shear bond strength of BD group was the highest and that of WMTA group was significantly lower than the others.

Evaluation of wettability characteristics and adhesion of resin composite to photo-polymerized pulp-capping materials with and without bioactive glass / Avaliação das características de molhabilidade e adesão da resina composta aos materiais fotopolimerizáveis com e sem vidro bioativo

Objective: This study evaluated the wettability and adhesive properties of three different photopolymerized resin-based pulp-capping materials with or without bioactive glass (BAG). Material and Methods: Cylindrical specimens (5 per group) were prepared from photo-polymerized pulp-capping materials (TER-TheraCal LC, BIN-Biner LC, and CAL-CalciPlus LC containing BAG). After surface finishing, contact angle measurements were made (θ)using the sessile drop method and surface free energy was calculated. For shear test, cylindrical acrylic blocks (N = 30) (diameter: 6 mm; height: 1 m) in the center were filled with the pulp-capping materials (N = 10 per group) flattened using a metal spatula and photo-polymerized. The specimens were stored at 37 °C in 100% humidity for 24 h prior to the bonding procedures. An adhesive system (CLEARFIL SE BOND, Kuraray) was applied on the material surfaces and photo-polymerized for 20 s. Then, resin composite material (Filtek Z250, 3M ESPE) was bonded on the substrate materials using translucent plastic molds (internal diameter: 2 mm; height: 2 mm). The specimens were photopolymerized with an LED photo-polymerization unit for 20 s. After polymerization, the specimens were stored at 37 °C, at 100% humidity for 24 h. Shear force was applied at the pulp-capping material and the resin composite interface In a universal testing machine (1 mm/min).Data were analyzed using 1-way ANOVA and Tukey`s tests at the significance level of 0.05. Results: Contact angle values showed significant difference between the 3 materials with group CAL presenting the lowest (35.35 ± 12.89) and group BIN the highest values (74.77 ± 13.56) (p < 0.05). Significantly lower surface energy was observed with BIN (36.22) (p 0.05). Group BIN (9.12 ± 3.45) showed significantly lower (p < 0.05) mean bond strength than those of TER (11.56 ± 5.67) and CAL (12.66 ± 4.34) (p > 0.05). Most of the observed modes of failures in all groups were of mixed type of failures. Conclusion: The bioglass used in Calciplus LC did not adversely affect the wettability, surface energy and adhesive properties. (AU)

Objetivo: Este estudo avaliou as propriedades de molhabilidade e adesivas de três diferentes materiais capeadores pulpares fotopolimerizaveis à base de resina, com ou sem vidro bioativo (BAG). Material e Métodos: Amostras cilíndricas (5 por grupo) foram preparadas a partir de materiais capeadores pulpares fotopolimerizáveis (TER-TheraCal LC, BIN-Biner LC e CAL-CalciPlus LC contendo BAG). Após o acabamento da superfície, as medidas do ângulo de contato foram feitas (θ) usando o método de gota séssil e a energia livre da superfície foi calculada. Para o ensaio de cisalhamento, blocos de acrílico cilíndricos (N = 30) (diâmetro: 6 mm; altura: 1 m) foram preenchidos no centro com os materiais de capeamento pulpar (N = 10 por grupo) achatados usando uma espátula metálica e fotopolimerizados. Os espécimes foram armazenados a 37 ° C em 100% de umidade por 24 h antes dos procedimentos de colagem. Um sistema adesivo (CLEARFIL SE BOND, Kuraray) foi aplicado nas superfícies do material e fotopolimerizado por 20 segundos. Em seguida, o material de resina composta (Filtek Z250, 3M ESPE) foi colado nos materiais do substrato utilizando moldes de plástico translúcido (diâmetro interno: 2 mm; altura: 2 mm). Os espécimes foram fotopolimerizados com um dispositivo de fotopolimerização de LED por 20 s. Após a polimerização, os espécimes foram armazenados a 37 °C, a 100% de umidade por 24 h. A força de cisalhamento foi aplicada no material capeador e na interface da resina composta em uma máquina universal de ensaios (1 mm / min). Os dados foram analisados por meio do teste de ANOVA e teste de Tukey ao nível de significância de 0,05. Resultados: Os valores do ângulo de contato mostraram diferença significativa entre os 3 materiais com o grupo CAL apresentando os menores valores (35,35 ± 12,89) e o grupo BIN os maiores valores (74,77 ± 13,56) (p < 0,05). Uma energia de superfície significativamente menor foi observada com o BIN (36,22) (p 0,05). O grupo BIN (9,12 ± 3,45) apresentou resistência de união média significativamente menor (p 0,05). A maioria dos modos de falhas observados em todos os grupos eram de tipo misto de falhas. Conclusão: O biovidro utilizado no Calciplus LC não afetou negativamente a molhabilidade, energia superficial e propriedades adesivas. (AU)

Comparison between calcium hydroxide mixtures and mineral trioxide aggregate in primary teeth pulpotomy: a randomized controlled trial

Abstract Objectives: To evaluate the effect of calcium hydroxide (CH) associated with two different vehicles as a capping material for pulp tissue in primary molars, compared with mineral trioxide aggregate (MTA). Methodology: Forty-five primary mandibular molars with dental caries were treated by conventional pulpotomy using one of the following materials: MTA only (MTA group), CH with saline (CH+saline group) and CH with polyethylene glycol (CH+PEG group) (15 teeth/group). Clinical and periapical radiographic examinations of the pulpotomized teeth were performed 3, 6, and 12 months after treatment. Data were tested by chi-squared analysis and a multiple comparison post-test. Results: The MTA group showed both clinical and radiographic treatment success in 14/14 teeth (100%), at all follow-up appointments. By clinical evaluation, no teeth in the CH+saline and CH+PEG groups had signs of mobility, fistula, swelling or inflammation of the surrounding gingival tissue. However, in the CH+saline group, radiographic analysis detected internal resorption in up to 9/15 teeth (67%), and inter-radicular bone resorption and furcation radiolucency in up to 5/15 teeth (36%), from 3 to 12 months of follow-up. In the CH+PEG group, 2/11 teeth (18%) had internal resorption and 1/11 teeth (9%) presented bone resorption and furcation radiolucency at all follow-up appointments. Conclusion: CH with PEG performed better than CH with saline as capping material for pulpotomy of primary teeth. However, both combinations yielded clinical and radiographic results inferior to those of MTA alone.

Biodentine como recubrimiento pulpar directo. Reporte de caso clínico / Biodentine as a diret pulp coating. Clinical case report

En los últimos años se han ido desarrollando técnicas y medicamentos nuevos para realizar procedimientos pulpares en dentición definitiva. El Biodentine es un nuevo material en el campo odontológico que se utiliza como sustituto bioactivo de la dentina, al aplicarlo favorece la cicatrización del tejido pulpar, aumentando la proliferación, la migración y la adhesión de las células pulpares madre de esta manera proporcionando excelentes propiedades de bioactividad y biocompatibilidad. Se presenta el reporte de un caso de un recubrimiento pulpar directo con Biodentine en un molar definitivo. Al seguimiento de la semana 2 desapareció sintomatología y a la semana 6 se observó formación de puente dentinario, certificando éxito clínico y radiográfico. El Biodentine se puede considerar como un medicamento idóneo y eficaz frente a un recubrimiento pulpar. (AU)

In recent years new techniques and new drugs have been developed to perform pulp procedures in definitive dentition. Biodentine is a new material in the dental field that is used as a bioactive substitute for dentin. When applied, it favors the healing of pulp tissue, increasing the proliferation, migration and adhesion of the mother pulp cells in this way, providing excellent properties of bioactivity and biocompatibility. In this article, we present the report of a case of a direct pulp coating with Biodentine in a definitive molar. At the follow-up of week 2 symptomatology disappeared and at week 6 dentin bridge formation was observed, certifying clinical and radiographic success. Biodentine can be considered as an ideal and effective drug against a pulp coating. (AU)

Dental Pulp Regeneration: Insights from Biological Processes / Regeneración pulpar: Perspectivas desde los procesos biológicos

Abstract One of the major approaches on dental research in this century is the development of biological strategies (tissue engineering) to regenerate/biomineralize lost dental tissues. During dentin- pulp regeneration, the interaction between stem cells, signaling molecules, biomaterials and the microenvironment in the periapical area drives the process for pulp tissue engineering. Understanding the signaling mechanisms and interactions involved with the biological process for the formation of a new tissue is essential. The knowledge of the micro-environment is the key for the application of tissue engineering. The present article is a short review of the current state of this topic, with the purpose of showing insights of pulp regeneration.

Resumen Actualmente la investigación en odontología se orienta al desarrollo de estrategias basadas en principios biológicos (ingeniería de tejidos) para la regeneración/biomineralización de estructuras dentales perdidas. El proceso de regeneración del complejo dentino-pulpar está guiado por la compleja interacción entre las células indiferenciadas de origen dental (DTSC), moléculas de señalización y biomateriales con el microambiente donde se va a restablecer. Es esencial comprender detalladamente, los mecanismos de señalización e interacciones involucradas en los procesos biológicos para la formación de un nuevo tejido, además de la identificación de los componentes presentes en los tejidos dentales implicados en este proceso (características del microambiente), ya que representan la base sobre la cual se debe emplear la ingeniería de tejidos. El presente articulo es una breve revisión del estado actual del tema, con el fin de entender el proceso de regeneración pulpar, basado en la comprensión de los fundamentos biológicos.

Clinical, radiographic and histological evaluation of primary teeth pulpotomy using mta and ferric sulfate

Abstract The aim of this study was to evaluate the clinical, radiographic and histological outcomes of the dentin-pulp complex from primary molars after pulpotomy with mineral trioxide aggregate (MTA) and 15.5% ferric sulfate (FS). Thirty-one primary molars were randomly allocated into MTA or FS groups. Clinical and radiographic evaluations were recorded at 3-, 6-, 12- and 18-month follow-up. Teeth at the regular exfoliation period were extracted and processed for histological analysis. Clinical and radiographic data were tested by statistical analysis (p≤0.01). Histological outcomes were analyzed descriptively. All of the treated teeth presented clinical success over the experimental periods. Both groups exhibited 100% of radiographic success at 3, 6 and 12 months. At the 18-month follow-up, one tooth from FS group presented inter-radicular radiolucency (p>0.01). Histologically, the treated teeth presented pulp vitality and absence of inflammatory infiltrate into the connective tissue. Only MTA group showed hard tissue barrier surrounded by odontoblasts over the pulp stumps. Both MTA and 15.5% FS are effective for pulpotomies of primary teeth. Although MTA is considered the first-choice material, FS may be a suitable alternative when treatment cost is an issue.

Resumo O objetivo deste estudo foi avaliar os resultados clínicos, radiográficos e histológicos do complexo dentino-pulpar de molares decíduos após pulpotomia com agregado trióxido mineral (MTA) e sulfato férrico (SF) 15,5%. Trinta e um molares decíduos foram alocados aleatoriamente nos grupos MTA ou SF. As avaliações clínicas e radiográficas foram realizadas aos 3, 6, 12 e 18 meses de acompanhamento. Os dentes no período regular de esfoliação foram extraídos e processados ​​para análise histológica. Os dados clínicos e radiográficos foram analisados estatisticamente (p≤0,01). O resultados histológicos foram analisados ​​descritivamente. Todos os dentes tratados apresentaram sucesso clínico ao longo dos períodos experimentais. Ambos os grupos exibiram 100% de sucesso radiográfico aos 3, 6 e 12 meses. Aos 18 meses de acompanhamento, um dente do grupo SF apresentou radiolucidez interradicular (p>0,01). Histologicamente, os dentes tratados apresentaram vitalidade pulpar e ausência de infiltrado inflamatório no tecido conjuntivo. Somente o grupo MTA mostrou barreira de tecido duro rodeada por odontoblastos sobre os cotos pulpares. MTA e SF 15,5% são eficazes para pulpotomias de dentes decíduos. Embora o MTA seja considerado o material de primeira escolha, o SF pode ser uma alternativa adequada quando o custo do tratamento é um problema.

Effects of mineral trioxide aggregate, BiodentineTM and calcium hydroxide on viability, proliferation, migration and differentiation of stem cells from human exfoliated deciduous teeth

Abstract Objective: The aim of the study was to evaluate the effects of the capping materials mineral trioxide aggregate (MTA), calcium hydroxide (CH) and BiodentineTM (BD) on stem cells from human exfoliated deciduous teeth (SHED) in vitro. Material and Methods: SHED were cultured for 1 - 7 days in medium conditioned by incubation with MTA, BD or CH (1 mg/mL), and tested for viability (MTT assay) and proliferation (SRB assay). Also, the migration of serum-starved SHED towards conditioned media was assayed in companion plates, with 8 μm-pore-sized membranes, for 24 h. Gene expression of dentin matrix protein-1 (DMP-1) was evaluated by reverse-transcription polymerase chain reaction. Regular culture medium with 10% FBS (without conditioning) and culture medium supplemented with 20% FBS were used as controls. Results: MTA, CH and BD conditioned media maintained cell viability and allowed continuous SHED proliferation, with CH conditioned medium causing the highest positive effect on proliferation at the end of the treatment period (compared with BD and MTA) (p<0.05). In contrast, we observed increased SHED migration towards BD and MTA conditioned media (compared with CH) (p<0.05). A greater amount of DMP-1 gene was expressed in MTA group compared with the other groups from day 7 up to day 21. Conclusion: Our results show that the three capping materials are biocompatible, maintain viability and stimulate proliferation, migration and differentiation in a key dental stem cell population.

Recent advances in direct pulp capping materials / 华西口腔医学杂志

The long-term effect of direct pulp capping and pulpotomy is closely related to the type of pulp capping materials. Various kinds of direct pulp capping materials are available, such as calcium hydroxide and mineral trioxide aggregates. Diverse new pulp capping materials have been reported recently. The excellent performance of calcium silicates has attracted much attention in previous studies. Moreover, enamel matrix derivative (Emdogain), which is capable of regeneration and remineralization, and other materials with similar capabilities have shown potential for use in pulp capping.

Avances en protección pulpar directa con materiales bioactivos / Recent advances in direct pulp capping with bioactive materials

Con el advenimiento de los materiales Bioactivos hoy hay un cambio de paradigma en el tratamiento de la protección pulpar directa. Está ampliamente demostrado en la literatura tanto en los estudios in vitro como in vivo, que estos materiales son más efectivos que el hidróxido de calcio para lograr cambios biológicos y microestructurales en el tejido pulpar y dentinario. Es así que surgen los materiales bioactivos, los cuales son sustancias que al ponerse en contacto con los tejidos vivos, provocan un efecto positivo sobre los mismos formando tejidos calcificados. Inducen una respuesta biológica específica en la interfase material-tejido. Actualmente los que cuentan con mayor aval científico son: MTA, Biodentine y Theracal LC.

Nowadays with the arrival of the Bioactive Materials, there has been an important change in the treatment of direct pulp capping. It is already probed, in studies in vitro and in vivo that these materials are more effective than calcium hydroxide as they obtain biological and microstructural changes in the pulpar and dentinal tissues.That is the reason for the appearance of the BIOACTIVE materials, which cause a specific biological response in the interface material-tissue when they are in contact with the vital tissues. The actual materials with the best scientific acceptance are: MTA, Biodentine and Theracal.

Spectrophotometric evaluation of calcium ion release from different calcium hydroxide preparations: an in-vitro study

Abstract: Pulp tissue conditions such as infections have long been treated with calcium hydroxide (CaOH). In the last decade, use of mineral trioxide aggregate (MTA) has gained ground. This study was carried out to comparatively evaluate the Ca release from CaOH powder with different vehicles and different types of MTA. Materials and Methods: 40 single rooted mandibular premolars were selected, decoronated and biomechanically prepared. They were randomly divided into four groups, consisting of 10 samples each. Root canals were packed with different preparations of CaOH and MTA. Calcium ion release was evaluated with an UV-spectrophotometer. Result: Amongst the CaOH preparations, using propylene glycol as a vehicle produced extended release of calcium ions (7.34 +/- 0.01) for a period of 14 days. Whereas, amongst MTA based products, MTA angelus produced the maximum release of calcium ions (2.42 +/- 0.010). A statistically significant difference was present between the four groups (p<0.05). Conclusion: Propylene glycol mixed with CaOH powder, produces a higher and extended release of calcium ions compared to distilled water. MTA angelus produces consistent calcium ion release.

BiodentineTM is cytocompatible with human primary osteoblasts

Abstract Calcium silicate-based materials have been widely studied due to their resemblance to, and similar applicability of, mineral trioxide aggregate (MTA). Among these, Biodentine™ (BD) was specifically designed as a "dentin replacement" material for applications such as root perforations, apexification, treatment of resorptive lesions, and as a retrograde filling material. The present study aimed to assess the in vitro response of human primary osteoblasts to BD using MTA AngelusTM as a reference material, by simultaneously analyzing three different cell viability parameters, namely mitochondrial activity, membrane integrity, and cell density. BD and MTA extracts were prepared by incubation on culture media for 24 h or 42 days after mixing. Primary human osteoblasts were exposed to extracts for 24 h, at 37oC with 5% CO2, and cell viability was evaluated by the XTT, NRU, and CVDE assays. Both materials induced cell viability levels higher than 70% when extracted for 24 h. However, when cells were exposed to extracts with increased conditioning times, MTA presented significant cytotoxic effects (p < 0.05) in comparison to the control and MTA at 24 h. After 42 days, the XTT assay identified a significant reduction in cell viability by BD when compared to the control (p<0.05), despite the fact that levels above the 70% viability cutoff were attained for biocompatible materials. It can be concluded that BD is cytocompatible with human primary osteoblasts, indicating its adequacy in direct contact with bone tissues.

Desenvolvimento e análise de bandagem de bioestimulação dentino/pulpar (BBio) / Development and analysis of dental/pulpar bio-stimulation bandage ("BBIO")

O desenvolvimento de biomateriais com aplicações na área da saúde mostram-se cada vez mais importantes e a procura por novos polímeros com propriedades bioativas, biodegradabilidade, atoxicidade são o foco das principais pesquisas em diferentes aplicações médicas e odontológicas. Os materiais capeadores pulpares evoluíram rapidamente na ultima década, sendo que são disponibilizadas atualmente diversas alternativas para uso clínico odontológico. Este trabalho teve como objetivo o desenvolvimento de um novo produto bioestimulador e capeador dentino/pulpar que poderá ser base para o desenvolvimento e recobrimento de scaffolds para reparo das diferentes estruturas dentárias. O desenvolvimento das bandagens BBio e os resultados obtidos nos testes das propriedades físico-químicas (absorção de água, perda de massa e pH), bem como as análises biológicas da morfologia celular e viabilidade celular com MTT a BBio apresentaram dados favoráveis e desejáveis para sua aplicação clínica. A propriedade de liberação de cálcio foi bastante promissora, sendo esta uma condição que dará a diferenciação positiva da BBio como um produto bioestimulador pulpar. Com esses dados pode-se concluir que a mesma se encontra dentro dos parâmetros desejados para o produto final e com propriedades semelhantes aos produtos existentes no mercado, de qualidade e aprovados pelas agências reguladoras.(AU)

The development of biomaterials with applications in the health area are increasingly important and the search for new polymers with bioactive properties, biodegradability and toxicity are the focus of the main researches in different medical and dental applications. The pulp capping materials evolved rapidly in the last decade, and several alternatives are now available for clinical dental use. This project aimed to develop a new biostimulating and dentin / pulp capping product that could be the basis for the development and recoating of "scaffolds" for repair of different dental structures. The development of the BBio bandages and the results obtained in the physical-chemical properties tests (water absorption, loss of mass and pH), as well as the biological analyzes of the cellular morphology and cell viability with MTT to BBio presented favorable and desirable data for its clinical application. The calcium release property was quite promising, and this is a condition that will give BBio a positive differentiation as a pulp biostimulator product. With this data it can be concluded that it is within the parameters desired for the final product and with properties similar to the products on the market, of quality and approved by the regulatory agencies.(AU)

Evaluation of the genotoxicity and mutagenicity of Ca3SiO5-based cement

Abstract Ca3SiO5 is new cement based on the composition of Portland that has been developed to have superior physicochemical and biological properties. In a clinical evaluation, the cement did not appear to have cytotoxic properties and allowed for the proliferation of pulp cells and gingival fibroblasts. However, no previous studies have evaluated the genotoxicity or the mutagenicity of Ca3SiO5in vivo. Therefore, the goal of this study is to evaluate the genotoxic and mutagenic potential of Ca3SiO5-based cement in vivo. Twenty-four male Wistar rats were divided into 3 groups (n = 8). Group A rats received subcutaneous implantation of Ca3SiO5 in the dorsum. Group B rats received a single dose of cyclophosphamide (positive control). Group C rats received subcutaneous implantation of empty tubes in the dorsum (negative control). After 24 hours, all animals were euthanized and the bone marrow of the femurs was collected for use in the comet assay and the micronucleus test. The comet assay revealed that the Ca3SiO5 group had a tail intensity of 23.57 ± 7.70%, the cyclophosphamide group had a tail intensity of 27.43 ± 7.40%, and the negative control group had a tail intensity of 24.75 ± 5.55%. The average number of micronuclei was 6.25 (standard deviation, SD = 3.53) in the Ca3SiO5 group, 9.75 (SD = 2.49) in the cyclophosphamide group, and 0.75 (SD = 1.03) in the negative control group. There was an increase in the micronuclei frequency in the Ca3SiO5 group compared to that of the negative control group (p < 0.05). Our data showed that exposure to the Ca3SiO5-based cement resulted in an increase in the frequency of micronuclei, but no genotoxicity was detected according to the comet assay.

Inflammatory effect of green propolis on dental pulp in rats

Pulpotomy in deciduous teeth is a controversial issue, especially with regard to alternative materials used for the direct pulp capping of the root canal pulp tissue. The aim of the present study was to perform a histological analysis of the initial reaction of the root canal pulp tissue in rats, following pulpotomy and pulp capping with (1) green propolis extract, (2) iodoform paste, (3) green propolis extract + iodoform and (4) calcium hydroxide paste with saline solution. Analyses were performed after 24 hours, 72 hours and 7 days. The substances containing green propolis extract and iodoform led to the production of an intense inflammatory infiltrate and necrosis in the root canal pulp tissue throughout the analyses. In the calcium hydroxide group, inflammatory infiltrate only prevailed at the 72-hour evaluation. Among the substances tested, calcium hydroxide paste induced the lowest intensity of inflammatory response in the root canal pulp tissue. Longer studies should be carried out to analyze the pulp repair process following pulpotomy and pulp capping with the compounds analyzed.