Biocompatibilidade em pulpotomia de dentes decíduos: melhor material e alternativas ao uso do MTA: revisão sistemática e meta-análise / Biocompatibility in pulpotomy in deciduous teeth: best material and alternatives to MTA use: a systematic review and meta-analysis

Introdução: A terapia pulpar vital é o tratamento que visa a manutenção da vitalidade pulpar e da função do dente. Para a pulpotomia, os materiais são escolhidos baseados em algumas características fundamentais, tais como a biocompatibilidade e bioatividade. Atualmente, o Agregado de Trióxido Mineral (MTA) é o mais comumente utilizado para este procedimento. Objetivo: Identificar o melhor material para uso em pulpotomia em dentes decíduos considerando a propriedade de biocompatibilidade, através de revisão sistemática da literatura e metanálise. Material e Métodos: A pergunta norteadora foi: "Qual é o melhor agente para pulpotomia em termos de biocompatibilidade?". Foi realizada pesquisa nas bases de dados eletrônicas Medline/PubMed, SciELO, LILACS e Web of Science sem restrição de data inicial até outubro de 2020, usando os seguintes descritores padronizados pelo Medical Subject Headings (MeSH): "pulpotomy", "pulp therapy", "biomaterials", "biocompatible materials", "pulp capping agent", "pulp capping materials".Resultados: Um total de 358 estudos foram identificados, sendo 15 deles selecionados para análise qualitativa e seis para metanálise. A revisão avaliou aspectos clínicos, radiográficos e histológicos, considerando diferentes períodos de acompanhamento, amostras e metodologias. Diversos materiais foram encontrados e o MTA foi o mais frequente. Embora os resultados qualitativos tenham sido pouco conclusivos em relação ao melhor deles, foi possível estabelecer que o Cimento Portland é uma alternativa viável para a substituição do MTA. Conclusão: A metanálise demonstrou que o MTA é o material mais favorável para uso em pulpotomias em dentes decíduos.

Introduction: Vital pulp therapy is the treatment aimed at maintaining pulp vitality and tooth function. For pulpotomy, materials are chosen based on some fundamental characteristics, such as biocompatibility and bioactivity. Currently, Mineral Trioxide Aggregate (MTA) is the most commonly used for this procedure. Objective: To identify the best material for use in pulpotomy in deciduous teeth considering the property of biocompatibility, through a systematic review of the literature and meta-analysis. Materials and Methods: The guiding question was: "What is the best agent for pulpotomy considering the biocompatibility property?". A search was performed in the electronic databases MEDLINE/PubMed, SciELO, LILACS and Web of Science without an initial date until October 2020, using the following descriptors recognized by Medical Subject Headings (MeSH): "pulpotomy", "pulp therapy", "biomaterials", "biocompatible materials'', "pulp capping agent", "pulp capping materials". Results: A total of 358 studies were identified, 15 of them selected to qualitative analysis and six to meta-analysis. The revision evaluated clinical, radiographic and histological aspects, considering different follow-up periods, samples and methodologies. Several materials were found and MTA was the most frequent. Although the qualitative results were inconclusive in relation to the best of them, it was possible to establish that the Portland Cement is a viable alternative for MTA replacement. Conclusion: The meta-analysis demonstrated that MTA is the most favorable material for use in pulpotomies in deciduous teeth.

Experimental resin-based dual-cured calcium aluminate and calcium titanate materials for vital pulp therapy

Abstract: This paper evaluates the physicochemical and biological properties of experimental resin-based dual-cured calcium aluminate (CA) and calcium titanate (CTi) materials for vital pulp therapy (VPT). The experimental dual-cured materials were obtained as two pastes: a) Bis-EMA 10, PEG 400, DHEPT, EDAB, camphorquinone, and butylated hydroxytoluene; and b) fluoride ytterbium, Bis-EMA 10, Bis-EMA 30, benzoyl peroxide, and butylated hydroxytoluene. The materials were divided into six groups based on the added calcium component: MTA (MTA®, Angelus); CLQ (Clinker-Fillapex®, Angelus); CA (calcined at ,1200°C in pastes a and b); CA800 (calcined at 800°C in paste a); CA1200 (calcined at 1,200°C in paste a); and CTi (paste a). The real-time degree of conversion and rate of polymerization (n = 3), diametral tensile strength (n = 10), hydrogen potential (n = 15), calcium ion release (n = 10), water sorption and solubility (n = 10), and cell viability (n = 6) were evaluated. One- and two-way ANOVA and Tukey's post hoc test were used in the analysis of the parametric data, and Kruskal-Wallis and Dunn's multiple tests were used to analyze the nonparametric data (α = 0.05). CLQ, CA800 and CA1200 had the highest diametral tensile strength. The water solubility of MTA was similar to that of CA800, CA1200 and CTi. CA800 and CA1200 resulted in cell viabilities similar to those of MTA and CLQ. The experimental dual-cured CA-based material that calcined at 800°C showed physicochemical and biological properties suitable for VPT, and similar to those of MTA.

The influence of the particle's size on the setting reaction of sol-gel derived calcium silicate particles / A influência do tamanho de partícula na reação de presa de cimentos de silicate de cálcio produzidos por sol-gel

Introduction: This study aims to analyze the influence of particles size of sol-gel derived calcium silicate particles in the setting reaction of bioactive endodontic cements. Materials and Methods: Sol-gel derived calcium silicate particles were synthesized and sieved to separate the particles in different sizes: CS400, CS200, and CS100. A commercial MTA (Control) was used as control. The particle size and the specific surface area were assessed by laser diffraction and nitrogen adsorption. The cements were prepared with water as the liquid for the reaction. The setting time was conducted according to ISO 6876, and the setting kinetics was analyzed by Fourier trans-formed infrared spectroscopy (FTIR) at different time points between 120s to 72h. Results: The particle size varied from 9.45µm (CS400 ) to 31.01 (Control). The higher specific surface area valuer reached 15.14g/cm2 in the CS400. The smallest particle sizes, the higher specific surface area, and the lowest setting time were found for CS400 (p < 0.05). Control presented the highest setting time (p < 0.05). The FTIR analyses showed the differences in materials structure over time, with faster hydration and crystallization for CS400. The setting kinetics was slower for Control even when compared to a sol-gel derived group with similar particle size. Conclusion:The route of synthesis and the particle size influences the setting reaction of calcium silicate-based cements. The reduction of particle size for sol-gel derived calcium silicates lead to the acceleration of the setting reaction of the produced bioactive endodontic cement.

Introdução: Este estudo tem como objetivo analisar a influência do tamanho de partículas de silicato de cálcio derivadas de sol-gel na reação de presa de cimentos endodônticos bioativos. Materiais e Métodos: Partículas de silicato de cálcio derivadas de sol-gel foram sintetizadas e peneiradas para separar as partículas em diferentes tamanhos: CS400, CS200 e CS100. Um MTA comercial (Controle) foi usado como controle. O tamanho das partículas e a área superficial específica foram avaliados por difração a laser e adsorção de nitrogênio. Os cimentos foram preparados com água como líquido para a reação. O tempo de presa foi conduzido de acordo com a ISO 6876, e a cinética de presa foi analisada por espectroscopia de infravermelho transformada de Fourier (FTIR) em diferentes pontos de tempo entre 120s a 72h. Resultados: O tamanho de partícula variou entre 9,45µm (CS400) e 31,01 (Controle). A maior área de superfície foi encontrada nas partículas do grupo CS400 (15.14g/cm2). Os menores tamanhos de partícula, a maior área de superfície específica e o menor tempo de presa foram encontrados para CS400 (p < 0,05). O Control apresentou o maior tempo de presa (p < 0,05). As análises de FTIR mostraram as diferenças na estrutura dos materiais ao longo do tempo, com hidratação e cristalização mais rápidas para CS400. A cinética de presa foi mais lenta para Control mesmo quando comparado a um grupo derivado de sol-gel com tamanho de partícula semelhante. Conclusão: A rota de síntese e o tamanho das partículas influenciam a reação de endurecimento dos cimentos à base de silicato de cálcio. A redução do tamanho de partícula para silicatos de cálcio derivados de sol-gel leva à aceleração da reação de pega do cimento endodôntico bioativo produzido.

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.

Glycerol Salicylate-based Pulp-Capping Material Containing Portland Cement

The purpose of this study was to evaluate the water sorption, solubility, pH and ability to diffuse into dentin of a glycerol salicylate-based, pulp-capping cement in comparison to a conventional calcium hydroxide-based pulp capping material (Hydcal). An experimental cement was developed containing 60% glycerol salicylate resin, 10% methyl salicylate, 25% calcium hydroxide and 5% Portland cement. Water sorption and solubility were determined based on mass changes in the samples before and after the immersion in distilled water for 7 days. Material discs were stored in distilled water for 24 h, 7 days and 28 days, and a digital pHmeter was used to measure the pH of water. The cement's ability to diffuse into bovine dentin was assessed by Raman spectroscopy. The glycerol salicylate-based cement presented higher water sorption and lower solubility than Hydcal. The pH of water used to store the samples increased for both cements, reaching 12.59±0.06 and 12.54±0.05 after 7 days, for Hydcal and glycerol salicylate-based cements, respectively. Both cements were able to turn alkaline the medium at 24 h and sustain its alkalinity after 28 days. Hydcal exhibited an intense diffusion into dentin up to 40 µm deep, and the glycerol salicylate-based cement penetrated 20 µm. The experimental glycerol salicylate-based cement presents good sorption, solubility, ability to alkalize the surrounding tissues and diffusion into dentin to be used as pulp capping material.

O objetivo deste estudo foi avaliar a sorção e solubilidade em água, pH e habilidade de difusão na dentina de um cimento para capeamento pulpar à base de glicerol salicilato e compará-lo a um cimento comercial para capeamento pulpar à base de hidróxido de cálcio (Hydcal). Um cimento experimental contendo 60% de resina de glicerol salicilato, 10% de salicilato de metila, 25% de hidróxido de cálcio e 5% de cimento Portland foi formulado. Sorção e solubilidade em água foram determinadas a partir da alteração na massa de espécimes antes e após a imersão em água destilada por 7 dias. Discos dos cimentos foram armazenados em água destilada por 24h, 7 dias e 28 dias e o pH da água foi aferido após cada período. A habilidade de difundir-se no interior de dentina bovina foi avaliada por espectroscopia Raman. O cimento à base de glicerol salicilato apresentou maior sorção e menor solubilidade em comparação com o Hydcal. O pH da água de armazenamento dos espécimes aumentou para ambos os cimentos, chegando a 12,59±0,06 e 12,54±0,05 após 7 dias, para o Hydcal e o cimento à base de glicerol salicilato, respectivamente. Os cimentos foram capazes de promover a alcalinização do meio após 24h e sustentaram a alcalinidade após 28 dias. Hydcal exibiu intensa difusão na dentina até 40 μm de profundidade e o cimento à base de glicerol salicilato penetrou 20 μm. O cimento experimental à base de glicerol salicilato apresentou adequada sorção, solubilidade, habilidade de alcalinizar o meio e difundir-se no interior da dentina para uso como um material para capeamento pulpar.