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.

Pulpotomía parcial con agregado de trióxido mineral (MTA) comparado con hidróxido de calcio en caries dentinaria profunda en pacientes con dientes permanentes inmaduros / Partial pulpotomy with mineral trioxide aggregate (MTA) versus calcium hydroxide in immature permanent teeth with deep caries

RESUMEN: Introducción: La pulpotomía parcial se utiliza para el tratamiento de caries con exposición pulpar en dientes permanentes inmaduros. El agregado de trióxido mineral (MTA) ha sido propuesto como uno de los biomateriales de elección para el tratamiento, pero existe incertidumbre en relación a su efectividad comparado con la del hidróxido de calcio. 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: Encontramos cinco revisiones sistemáticas, que incluyeron tres estudios primarios, de los cuales todos corresponden a ensayos aleatorizados. Concluimos que la pulpotomía parcial con agregado de trióxido mineral (MTA) podría resultar en poca o nula diferencia en la tasa de éxito comparado a la pulpotomía parcial con hidróxido de calcio, pero la certeza de la evidencia es baja.

ABSTRACT: Introduction: Partial pulpotomy is the treatment of choice following carious pulp exposure in immature permanent teeth. Mineral trioxide aggregate (MTA) has been suggested as the biomaterial first option for treatment, but there is still uncertainty regarding its effectiveness compared to calcium hydroxide. 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 five systematic reviews including three studies overall, of which all were randomized trials. We conclude that partial pulpotomy with mineral trioxide aggregate (MTA) may make little or no difference to success rate compared to partial pulpotomy with calcium hydroxide, however, the certainty of the evidence has been assessed as low.

Destoxificação e perfil nutricional da torta de mamona destoxificada por diferentes soluções alcalinas / [Detoxification and nutritional profile of the detoxified castor by different alkaline solutions]

Objetivou-se avaliar a destoxificação da torta de mamona bruta (TMB), por meio de dois produtos alcalinos em diferentes concentrações, e seus efeitos sobre a composição química, a degradabilidade in situ da MS e o fracionamento de proteínas. Utilizou-se o hidróxido de cálcio [Ca(OH)2] e o hidróxido de sódio (NaOH) em duas concentrações (60 e 90 gramas), diluídos em quatro quantidades de água (1.000; 1.500; 2.000 e 2.500mL de água por quilo de TMB). Observou-se que, das diferentes concentrações utilizadas, somente a utilização de 90 e 60 gramas de Ca(OH)2 e NaOH, respectivamente, conseguiu destoxificar 100% da TMB, ambas diluídas em 2.000mL de água. Por outro lado, ao avaliar o tempo mínimo de contato dos reagentes com a TMB para uma máxima destoxificação, observou-se que três horas de contato é o tempo necessário para os reagentes diminuírem em 100% as proteínas citotóxicas, além de não deixar atividade hemaglutinante nesse material. A destoxificação com o NaOH proporcionou maior degradação das proteínas solúveis e da matéria seca, favorecendo a disponibilização do nitrogênio não proteico, estando sua aplicação em escala industrial na dependência de estudos sobre viabilidade operacional e econômica.(AU)

This study aimed to evaluate the detoxification of crude castor (DCC) through two alkaline products in different concentrations and their effects on the chemical composition, in situ degradability of DM and the fractionation of proteins. We used the calcium hydroxide [Ca(OH)2] and sodium hydroxide (NaOH) in two concentrations (60 and 90 grams) diluted in 4 quantities of water (1,000; 1,500; 2,000 and 2,500ml of water per kilo of DCC). It was observed that in the different concentrations used, only the use of 90 and 60 grams of Ca(OH)2 and NaOH, respectively managed to detoxify 100% of the DCC, both diluted in 2,000ml of water. On the other hand, when assessing the minimum time of contact of the reagents with the DCC for maximum detoxification, it was observed that with three hours of contact is the time required for the reagents decrease in 100% of the cytotoxic proteins, in addition to not leave haemagglutinating activity in this material. The detoxification with NaOH provided greater degradation of soluble proteins and degradation of dry matter, favoring the provision of non-protein nitrogen, while its application on an industrial scale is in the dependence of studies on operational feasibility and cost.(AU)

In vitro treatment of Enterococcus faecalis with calcium hydroxide impairs phagocytosis by human macrophages.

OBJECTIVE: Monocyte-derived macrophages (MDMs) ability to phagocytize and produce nitric oxide (NO) was tested against root-canal strains of Enterococcus faecalis submitted to alkaline stress. Root-canal strains were also compared with urine Enterococci. MATERIALS AND METHODS: Enterococcus faecalis were stressed with alkaline-BHI broth and incubated in vitro at a cell/bacteria ratio of 1:5. Phagocytosis was analyzed by fluorescence microscopy using acridine orange stain, and NO concentration was measured in supernatants. RESULTS AND CONCLUSIONS: Alkaline-stress significantly impaired MDMs phagocytosis of E. faecalis strains analyzed, except in ATCC4083 isolated from a pulpless tooth, but NO production was unchanged. Comparison of different strains showed the urine isolate had higher NO levels than root canal strains. Alterations in the bacterial cell wall structures after alkaline-stress possibly made bacteria less recognizable and phagocytized by MDMs but did not affect their ability to activate NO production. Furthermore, root canal strains elicited different responses by immune cells compared with strains from urine. Clinically, impaired phagocytosis of E. faecalis could contribute to their persistence in root canal systems previously treated with calcium hydroxide.

Estimation of genomic instability and mitochondrial DNA damage induction by acute oral administration of calcium hydroxide normal- and nano- particles in mice.

Nowadays, there is increasing interest in using calcium hydroxide (Ca(OH)2) nanoparticles rather than normal-sized Ca(OH)2 because of its higher antimicrobial activities. However, the genotoxicity of Ca(OH)2 nanoparticles has not been well investigated. Therefore, this study was performed to estimate the possible genomic instability and mitochondrial DNA damage induction by normal and nano-sized Ca(OH)2 particles in mice. Oral administration of normal or nano-sized Ca(OH)2 particles induced DNA breakages and apoptosis causing genomic instability as a result of increased Calcium content, ROS and MDA levels and decreased SOD and Gpx activities reversely proportional to Ca(OH)2 particles size in the liver, brain and bone marrow tissues. However, decreases in mitochondrial membrane potential concurrently with downregulated expression of POLG, POLG1 and TFAM genes were only observed in the brain and bone marrow tissues confirmed mitochondrial DNA damage. In contrast, the expressions of POLG, POLG1 and TFAM genes have been improved and mitochondrial membrane potential has not unchanged in liver tissues. Conclusion: single oral administration of normal or nano-sized Ca(OH)2 particles induced genomic instability through ROS generation that exhausted the antioxidant defense system in the liver, brain and bone marrow tissues but impaired the mitochondrial DNA only in the brain and bone marrow tissues.

Intracanal Irrigating Solutions Prior to Calcium Hydroxide Medication and Its Effects on Root Dentin Strength

Abstract The aim of this study was to assess the effects of intracanal irrigation with sodium hypochlorite (NaOCl) and ethylenediaminetetracetic acid (EDTA) prior to calcium hydroxide medication on the compressive strength of root dentin. Forty-eight roots with single and straight canals were instrumented with a crown-down technique using Flexofile files and Gates Glidden burs, under 0.9% sodium chloride (NaCl) irrigation. Root canals were randomly separated into 4 groups (n=12), according to the irrigating solution: Control Group, 0.9% NaCl; GroupNaOCl, 1% NaOCl; GroupEDTA, 17% EDTA; and GroupEDTA+NaOCl, 17% EDTA and 1% NaOCl. Solutions remained for 40 min, renewed every 10 min, except for GroupEDTA+NaOCl, where the solutions were alternated every 10 min. Canals were dried and filled with calcium hydroxide paste, and radiographed. Each canal was sealed and stored at 37 °C for 30 days. After this period, the roots were cut 1 mm below the cementoenamel junction and 6 mm apically from this point in order to obtain 6 mm-long cylinders. The compressive test was conducted with a crosshead speed of 1 mm/min. The means (±SD) (MPa) of compressive strength were: Control Group, 151.23±94.36; GroupNaOCl, 167.50±57.25; GroupEDTA, 108.79±99.88; GroupEDTA+NaOCl, 60.12±92.10. Significant statistical differences among groups were found (ANOVA and Tukey, a=5%, p=0.02). Control Group and GroupNaOCl showed higher means of compressive strength than GroupEDTA+NaOCl. Intracanal irrigation with 17% EDTA and 1% NaOCl produced a significant reduction of dentin compressive strength 30 days after medication with calcium hydroxide.

Resumo O objetivo desse estudo foi avaliar o efeito da irrigação intracanal com hipoclorito de sódio (NaOCl) e ácido etilenodiamino tetracético (EDTA) previamente à medicação de hidróxido de cálcio na resistência à compressão da dentina radicular. Quarenta e oito raízes com canais únicos e retos tiveram os canais instrumentados pela técnica coroa-ápice com limas Flexofile e brocas Gates Glidden sob irrigação com solução salina (NaCl) a 0,9%. Os canais radiculares foram separados em 4 grupos (n=12), de acordo com a solução irrigadora: Grupo Controle, NaCl 0,9%; GrupoNaOCl, NaOCl 1%; GrupoEDTA, EDTA 17%; e GrupoEDTA+NaOCl, NaOCl 1% e EDTA 17%. As soluções permaneceram por 40 min, sendo renovadas a cada 10 min, exceto para o GrupoEDTA+NaOCl, onde as soluções foram alternadas a cada 10 min. Os canais foram secos, preenchidos com pasta de hidróxido de cálcio e radiografados. Cada canal foi selado e mantido a 37 °C por 30 dias. Após esse período, as raízes foram cortadas 1 mm abaixo da junção cemento-esmalte e 6 mm apicalmente a este corte, a fim de obter cilindros de 6 mm de comprimento. O teste de compressão foi realizado com velocidade de cruzeta de 1 mm/min. As médias (±SD) da resistência à compressão em MPa foram: Grupo Controle, 151.23±94.36; GrupoNaOCl, 167.50±57.25; GrupoEDTA, 108.79±99.88; GrupoEDTA+NaOCl, 60.12±92.10. Diferenças estatisticamente significativas foram encontradas entre os grupos (ANOVA e Tukey; a=0,05; p=0,02). O Grupo Controle e o GrupoNaOCl obtiveram maiores médias de resistência à compressão em relação ao GrupoEDTA+NaOCl. A irrigação intracanal com EDTA 17% e NaOCl 1% promoveu redução significativa da resistência à compressão da dentina, após 30 dias de medicação intracanal com hidróxido de cálcio.

Fosfato tricálcico e hidróxido de cálcio no reparo ósseo em coelho. Estudo histológico e histomorfométrico / Tricalcium phosphate and calcium hydroxide in rabbit bone repair. Histological and histomorphometric evaluation

A deficiência óssea requer procedimentos restauradores como uso de enxertos e substitutos ósseos para a reabilitação estética e funcional. Com o desenvolvimento dos biomateriais, a biocerâmica à base de fosfato de cálcio tornou-se alternativa promissora para a recomposição de estruturas ósseas, entretanto não apresenta potencial de osteoindução. O material hidróxido de cálcio (Ca(OH)2) demonstra propriedades antibacterianas e capacidade de induzir a formação de tecido ósseo. O objetivo deste trabalho foi avaliar o processo de reparo ósseo proporcionado pelo BTCP e Ca(OH)2 , isolados e associados. Realizou-se experimento em tíbias posteriores de dezoito coelhos. Dois animais receberam marcadores ósseos para fluorescência (alizarina, calceína e tetraciclina), e para cada tíbia foi utilizado um tipo de material de preenchimento (BTCP, Ca(OH)2, BTCP com Ca(OH)2 e sangue como controle); sendo eutanasiados após 56 dias para a análise de fluorescência e histomorfometria. Os 16 coelhos restantes foram aleatoriamente selecionados para receber os quatro materiais de preenchimento. Estes foram eutanasiados nos tempos de 14, 28, 42 e 56 dias para a análise morfológica microscópica com coloração em hematoxilina e eosina. Observou-se formação óssea em todos os grupos, e os que utilizaram BTCP apresentaram atraso para o início da reparação.

O sítio preenchido com sangue ocorreu apenas o reparo da estrutura lesada, consistindo na reconstituição da cortical óssea e tecido medular em 28 dias. Aos 56 dias, o grupo de BTCP com Ca(OH)2 apresentou maior formação de trabéculas no interior da tíbia. Na avaliação histomofométrica, o marcador calceína apresentou maiores valores de deposição óssea em relação à alizarina e tetraciclina. Conclui-se que os biomateriais BTCP e Ca(OH)2 estão diretamente envolvidos na formação de tecido ósseo no interior do defeito; a combinação do Ca(OH)2 com BTCP mostrou aumento do potencial de formação óssea; e houve maior deposição óssea no período entre quinta e sexta semana de reparação indicado pelo marcador calceína.

Insufficient bone volume requires restorative procedures such as use of grafts and bone substitutes for cosmetic and functional rehabilitation. The development of biomaterials made available bioceramic based on calcium phosphate that is showing to be promising alternatives for the restoration of bony structures, however it do not has osteoinductive potential. Calcium hydroxide (Ca(OH)2) shows antibacterial properties and induce bone tissue formation as well. The objective of this research was to evaluate the bone healing process promoted by BTCP and Ca(OH)2 isolated or conjugated. The experiment was conducted in posterior rabbit tibiae of 18 animais. Two animais received bone markers (alizarin, calcein, tetracycline) and each of their tibias received a type offiller material (BTCP, Ca(OH)2, BTCP plus Ca(OH)2 and blood as control group), being euthanized after 56 days for the histomorphometry and fluorescence analysis. The remaining 16 rabbits were randomly selected to receive one of the 4 filling materiais. These rabbits were euthanized on 14,28,42 and 56 days for the micromorphological analysis in hematoxylin and eosin slides. The bone formation was observed in ali groups, and who used BTCP had delay to the start of repair. The site filled with blood occurred only repair of the damaged structure, consisting of the reconstitution of the bone cortical and medullary tissue in 28 days. After 56 days, the BTCP group with Ca(OH)2 showed higher trabecular formation inside the tibia. In histomorfometric evaluation, the marker calcein had higher bone deposition values in relation to alizarin and tetracycline. It was concluded that the biomaterials BTCP and Ca(OH)2 are directly involved in the formation of bone tissue; the conjugation of Ca(OH)2 with BTCP increased bone formation potential; and there was greater bone deposition in the period between the fifth and sixth week of repairs indicated by calcein marker.

Fosfato tricálcico e hidróxido de cálcio no reparo ósseo em coelho. Estudo histológico e histomorfométrico / Tricalcium phosphate and calcium hydroxide in rabbit bone repair. Histological and histomorphometric evaluation

A deficiência óssea requer procedimentos restauradores como uso de enxertos e substitutos ósseos para a reabilitação estética e funcional. Com o desenvolvimento dos biomateriais, a biocerâmica à base de fosfato de cálcio tornou-se alternativa promissora para a recomposição de estruturas ósseas, entretanto não apresenta potencial de osteoindução. O material hidróxido de cálcio (Ca(OH)2) demonstra propriedades antibacterianas e capacidade de induzir a formação de tecido ósseo. O objetivo deste trabalho foi avaliar o processo de reparo ósseo proporcionado pelo BTCP e Ca(OH)2 , isolados e associados. Realizou-se experimento em tíbias posteriores de dezoito coelhos. Dois animais receberam marcadores ósseos para fluorescência (alizarina, calceína e tetraciclina), e para cada tíbia foi utilizado um tipo de material de preenchimento (BTCP, Ca(OH)2, BTCP com Ca(OH)2 e sangue como controle); sendo eutanasiados após 56 dias para a análise de fluorescência e histomorfometria. Os 16 coelhos restantes foram aleatoriamente selecionados para receber os quatro materiais de preenchimento. Estes foram eutanasiados nos tempos de 14, 28, 42 e 56 dias para a análise morfológica microscópica com coloração em hematoxilina e eosina. Observou-se formação óssea em todos os grupos, e os que utilizaram BTCP apresentaram atraso para o início da reparação. O sítio preenchido com sangue ocorreu apenas o reparo da estrutura lesada, consistindo na reconstituição da cortical óssea e tecido medular em 28 dias. Aos 56 dias, o grupo de BTCP com Ca(OH)2 apresentou maior formação de trabéculas no interior da tíbia. Na avaliação histomofométrica, o marcador calceína apresentou maiores valores de deposição óssea em relação à alizarina e tetraciclina. Conclui-se que os biomateriais BTCP e Ca(OH)2 estão diretamente envolvidos na formação de tecido ósseo no interior do defeito; a combinação do Ca(OH)2 com BTCP mostrou aumento do potencial de formação óssea; e houve maior deposição óssea no período entre quinta e sexta semana de reparação indicado pelo marcador calceína.

Insufficient bone volume requires restorative procedures such as use of grafts and bone substitutes for cosmetic and functional rehabilitation. The development of biomaterials made available bioceramic based on calcium phosphate that is showing to be promising alternatives for the restoration of bony structures, however it do not has osteoinductive potential. Calcium hydroxide (Ca(OH)2) shows antibacterial properties and induce bone tissue formation as well. The objective of this research was to evaluate the bone healing process promoted by BTCP and Ca(OH)2 isolated or conjugated. The experiment was conducted in posterior rabbit tibiae of 18 animais. Two animais received bone markers (alizarin, calcein, tetracycline) and each of their tibias received a type offiller material (BTCP, Ca(OH)2, BTCP plus Ca(OH)2 and blood as control group), being euthanized after 56 days for the histomorphometry and fluorescence analysis. The remaining 16 rabbits were randomly selected to receive one of the 4 filling materiais. These rabbits were euthanized on 14,28,42 and 56 days for the micromorphological analysis in hematoxylin and eosin slides. The bone formation was observed in ali groups, and who used BTCP had delay to the start of repair. The site filled with blood occurred only repair of the damaged structure, consisting of the reconstitution of the bone cortical and medullary tissue in 28 days. After 56 days, the BTCP group with Ca(OH)2 showed higher trabecular formation inside the tibia. In histomorfometric evaluation, the marker calcein had higher bone deposition values in relation to alizarin and tetracycline. It was concluded that the biomaterials BTCP and Ca(OH)2 are directly involved in the formation of bone tissue; the conjugation of Ca(OH)2 with BTCP increased bone formation potential; and there was greater bone deposition in the period between the fifth and sixth week of repairs indicated by calcein marker.

Influence of calcium hydroxide-loaded microcapsules on osteoprotegerin and receptor activator of nuclear factor kappa B ligand activity.

INTRODUCTION: Calcium hydroxide (Ca[OH]2) microcapsules were synthesized to allow controlled release of Ca(OH)2. The aim of this study was to evaluate the influence of Ca(OH)2 microcapsules on osteoprotegerin (OPG) activity, receptor activator of nuclear factor kappa B ligand (RANKL) activity, and the OPG/RANKL ratio compared with pure Ca(OH)2 powder and Vitapex (Neo Dental Chemical Products Co Ltd, Tokyo, Japan). METHODS: One formula of Ca(OH)2 microcapsules was evaluated, and pure Ca(OH)2 powder was used as a control. A commonly used Ca(OH)2 medication containing an oily vehicle (Vitapex) was also evaluated, and the in vitro release profile of Vitapex was studied. The human osteosarcoma cell line MG63 was used to evaluate the influence of Ca(OH)2 microcapsules, pure Ca(OH)2 powder, and Vitapex on OPG and RANKL activity. The relative messenger RNA (mRNA) expression of OPG and RANKL was determined by real-time polymerase chain reaction. The protein expression of OPG and RANKL in supernatants was measured using enzyme-linked immunosorbent assay. RESULTS: Vitapex prolonged the release of Ca(OH)2 compared with pure Ca(OH)2 powder, and the release rate of Vitapex was faster than that of the microcapsules. The OPG/RANKL ratio in the microcapsules group was up-regulated at both the mRNA and protein levels compared with the negative control group and the pure Ca(OH)2 powder group. The ratio in the Vitapex group was lower than the microcapsule group both at the mRNA and protein levels. CONCLUSIONS: Ca(OH)2 microcapsules increased the expression of OPG although they did not increase the expression of RANKL compared with pure Ca(OH)2 powder and Vitapex. This increase in expression led to an increase in the OPG/RANKL ratio and eventual inhibition of osteoclast activity.

The effect of frequency of calcium hydroxide dressing change and various pre- and inter-operative factors on the endodontic treatment of traumatized immature permanent incisors.

AIM: The objectives of this clinical study were as follows: (i) to determine the effect of frequency of calcium hydroxide [Ca(OH)(2)] dressing change on the apical barrier formation in immature permanent incisors with necrotic pulps and (ii) to investigate the effect of various clinical factors before and during treatment that may be associated with the frequency of Ca(OH)(2) dressing changes. METHODS: The study involved 21 healthy subjects, 8-12 years old. Twenty-three immature traumatized permanent maxillary central incisors were treated using Ca(OH)(2) powder mixed with barium sulfate and distilled water. The progress of barrier formation was reviewed after 6 months of first placement of Ca(OH)(2) and then every 3 months until the detection of an apical barrier. Clinical and radiographic evaluations were performed before and after treatment. Data were evaluated using a chi-square test. RESULTS: Apical barrier formation was successful for all 23 teeth. Seventeen teeth (74%) needed only a single application of Ca(OH)(2), while six teeth (26%) required more than one application. The average time of apical barrier formation was 30 weeks, and the mean number of Ca(OH)(2) dressing changes was 1.3. A significant positive association was found between teeth that presented with displacement and the number of Ca(OH)(2) dressing changes (P = 0.004). CONCLUSION: An initial 6-month application of Ca(OH)(2) dressing followed by 3-month replacements (usually in teeth presenting with displacement and/or sinus tracts) may be successfully used in apexification treatment. This would assist in reducing the number of Ca(OH)(2) dressing changes, number of appointments, cost of treatment and radiation exposure.

Análisis morfométrico del número de odontoblastos en recubrimientos directos con hidróxido de calcio y propóleos en canes / Morphometric analysis of odontoblasts number in direct capping with calcium hydroxide and propolis in dogs

El propóleos se ha utilizado en medicina desde épocas antiguas, una de sus indicaciones en medicina oral y odontológica es como material de recubrimiento directo. Así, el objetivo de este estudio fue cuantificar la neoformación odontoblástica en piezas dentarias de canes en recubrimientos directos. Se realizaron perforaciones en un total de 12 piezas dentarias, la mitad de las cuales fueron recubiertas con propóleos y la otra mitad con hidróxido de calcio. En todos los casos se obturaron las piezas dentarias con cemento de vidrio-ionómero. Al cabo de dos semanas, se realizaron las extracciones de las piezas dentarias, fijándolas en formalina tamponada; se efectuaron cortes histológicos de las piezas, los cuales se tiñeron con hematoxilina-eosina, con el fin de poder realizar la cuantificación de los núcleos odontoblásticos presentes tanto en las zonas alejadas de la perforación, como en las zonas cercanas a las lesiones. Se observó una similar actividad odontoblástica en las zonas cercanas a las lesiones al utilizar cualquiera de los dos materiales (p=0,9325), diferenciándose solamente en la disposición de las células neoformadas, que en el caso de utilizar propóleos fueron en empalizada, semejante a las zonas sanas, en cambio, al utilizar hidróxido de calcio no se observó dicho ordenamiento.

Since ancient times, propolis has been used in medicine, while in oral medicine and dentistry it has been indicated as a direct capping material.The aim of this study was to quantify the odontoblast activity in drilling holes on dog's teeth (canine and incisor) during direct capping.Perforations were carried out in a total sample of 12 dental pieces. In half of the sample teeth were capped with propolis, and in the other half with calcium hydroxide. In all cases teeth were obturated with glass ionomer cement. Extraction of the teeth was realized after two weeks, and teeth were fixed in buffered formalin. Histological cuts of the pieces were made and stained with hematoxylin-eosin in order to carry out quantification of nuclei presence in healthy areas (away from the perforation, as well as in areas adjacent to injuries. Results showed similar odontoblast activity while using either of the materials, (p=0.9325), only differing in the arrangement of newly formed cells which in the cases where propolis was used, were palisading, similar to healthy areas. On the other hand, the same order was not observed when calcium hydroxide was used.

Evaluation of carbon dioxide laser irradiation associated with calcium hydroxide in the treatment of dentinal hypersensitivity. A preliminary study.

Attempts have been made to treat dentinal hypersensitivity by sealing exposed dentinal tubules, and the carbon dioxide (CO(2)) laser has been shown to have a sealing effect on dentinal surfaces. The purpose of this study was to analyze the morphological ultra-structure and temperature change after CO(2) laser irradiation of dentin. Fourteen human third molars were selected and cleaned. An area was delimited, and the samples were randomly divided into seven groups: Group 1 (G1): control; G2, calcium hydroxide paste (CA) + CO(2) laser (L) (0.5 W/63,69 W/cm(2)); G3, CA + L (1 W/125,38 W/cm(2)); G4, CA + L (1.5 W/191,08 W/cm(2)); G5, L (0.5 W); G6, L (1 W); G7, L (1.5 W). All irradiation was performed in unfocused mode. The electron micrographs were analyzed by three observers. For temperature analysis, a thermocouple was used. Data were subjected to statistical analysis. The Kruskal-Wallis non-parametric test showed statistical differences between the groups (P < 0.05). For the two by two comparisons, all groups treated with calcium hydroxide paste presented significantly higher mean scores. In the groups treated by CO(2) laser only, fusion, re-crystallization, cracks and carbonization were observed. A change of 1 ± 5°C was noted in the temperature. Under the limitation of an in vitro study, and with the protocols used, we concluded that CO(2) laser is safe to use for the establishment of partial fusion and re-solidification of the dentinal surface.

Microscopic cleanliness evaluation of the apical root canal after using calcium hydroxide mixed with chlorhexidine, propylene glycol, or antibiotic paste.

This study evaluated cleaning of the dentinal wall after removal of different calcium hydroxide pastes. Sixty-eight single-rooted teeth were prepared using the step-back technique and randomly divided into 4 groups according to medication used: Ca(OH)2 with 0.2% chlorhexidine solution (Group 1), Ca(OH)2 with propylene glycol (Group 2), Ca(OH)2 with antibiotic paste (ciprofloxacin, metronidazole) and distilled water (Group 3), and Ca(OH)2 with antibiotic paste and propylene glycol (Group 4). The samples were stored at 37 °C and 100% relative humidity for 21 days. The medicaments were removed using 5 mL 1% NaOCl, instrumentation with master apical file, 5 mL 1% NaOCl, patency with the K-file #10, ultrasonic instrumentation, and 10 mL 17% EDTA-T. The specimens were analyzed using scanning electron microscopy and chemical analysis. The Kruskal-Wallis (α = 5%) test showed that were no differences between the experimental groups when comparing Ca(OH)2 removal (P = .0951). The chi-square test (α = 5%) indicated a predominance of Ca(OH)2 obstructing dental tubules in all groups. On the basis of the methodology applied, it was concluded that the apical dentine surface remained equally covered by Ca(OH)2, regardless of the vehicle used.

Efficacy of smear layer removal by cavity cleaning solutions: an atomic force microscopy study / Eficácia da remoção da lama dentinária por soluções de limpeza cavitária: estudo de microscopia de força atômica

PURPOSE: To evaluate the efficacy of smear layer removal by cavity cleaning agents by the use of atomic force microscopy (AFM). METHODS: Five intact human third molars were sectioned in the coronal portion to obtain dentin disks, which were ground with 600-grit abrasive paper for 10 s. Serial longitudinal sections were made perpendicular to each other to create four specimens, from each tooth. The specimens were divided into four treatment groups: GI, 2 percent chlorhexidine; GII, calcium hydroxide solution; GIII, 1.23 percent fluoride solution; and GIV, 37 percent phosphoric acid. The solutions were applied with a brush for 60 s, with the exception of the 37 percent phosphoric acid, which was applied for 15 s and rinsed with distilled water for 60 s. The specimens were examined by AFM. RESULTS: All of the specimens in GI and GII showed 100 percent of the dentin tubules obliterated by the smear layer. However, all of the specimens in GIII and GIV showed 0 percent of the dentin tubules obliterated by the smear layer. CONCLUSION: The 1.23 percent fluoride solution was effective in removing the smear layer and can be used as a cavity cleanser.

OBJETIVO: Avaliar a eficácia da remoção de lama dentinária por agentes de limpeza cavitária através da análise de microscopia de força atômica (MFA). METODOLOGIA: Cinco terceiros molares humanos hígidos foram seccionados transversalmente na porção coronária, obtendo discos de dentina de 2 mm, que foram desgastados com lixas de granulação 600, por 10 s.Foram feitos cortes seriados longitudinais e perpendiculares entre si, obtendo-se quarto espécimes de cada dente. Os espécimes foram divididos em 4 grupos: GI- clorexidina a 2 por cento; GII- água de hidróxido de cálcio; GIII- solução fluoretada a 1,23 por cento; GIV - ácido fosfórico 37 por cento. As soluções foram aplicadas com pincel por 60 s, com exceção do ácido fosfórico que foi aplicado por 15 s e lavado com água destilada pelo mesmo tempo. Os espécimes foram analisados por MFA. RESULTADOS: Todos os espécimes de GI e GII apresentaram 100 por cento dos túbulos dentinários obliterados por lama dentinária. Os espécimes de GIII e GIV apresentaram 0 por cento dos túbulos obliterados por lama dentinária. CONCLUSÃO: A solução de fluoretada a 1,23 por cento foi eficiente na remoção de lama dentinária, podendo ser empregada na limpeza de cavidades.

A ação do hidróxido de cálcio frente ao enterococcus faecalis nos casos de periodontite apical secundária: [revisão] / The action of calcium hydroxide against enterococcus faecalis in cases of secondary apical periodontitis: [review]

Introdução: a infecção da polpa e dos tecidos periapicais tem a sua etiologia discutida há anos. A periodontite apical é caracterizada por ser de origem polimicrobiana, sendo o Enterococcus faecalis o microorganismo mais comumente encontrado. Em situações clínicas, o objetivo do tratamento endodôntico é eliminar micro-organismos do sistema de canais radiculares. As medicações intracanal são um importante passo no tratamento e devem ser efetivas frente aos micro-organismos que resistem ao preparo do canal radicular. Dentre as medicações empregadas, o hidróxido de cálcio é utilizado rotineiramente como medicação intracanal. Sua ação se deve ao fato de estabelecer um pH altamente alcalino dentro do canal radicular, 12,5 aproximadamente, no qual a maioria dos microorganismos não consegue sobreviver. Objetivo: realizar uma revisão de literatura sobre a relação do Enterococcus faecalis no insucesso endodôntico e a efetividade do hidróxido de cálcio nesta situação clínica. Conclusão: a ação do hidróxido de cálcio frente ao Enterococcus faecalis é limitada.

Introduction: Pulp and periapical tissue infection etiology has been discussed for many years. Apical periodontitis is characterized by multimicrobial flora origin, in which Enterococcus faecalis is the microorganism more frequently found. In clinical situations, the aim of endodontic treatment is to remove microorganisms of the system of root canals. Intra canal medications are an important step in the treatment and they must be effective in microorganisms that resist the preparation of the root canal. Among all used medications, the calcium hydroxide is frequently used. It acts establishing a highly alkaline pH inside the root canal, 12.5 approximately, in which most of the microorganisms do not manage to survive.Aim: to make a review of the literature about the relationship on the Enterococcus faecalis on endodontic failure and calcium hydroxide effectiveness in this clinical situation. Conclusion: Calcium hydroxide has limited action against Enterococcus faecalis.

[Endodontic treatment of teeth with Cupral nanoimpregnation application and pins from polypropylene].

In experimental research on 52 removed teeth an opportunity of sharing of a technique nanoimpregnation dentin a root hydroxide cuprum-calcium (Cupral) and sealings root the channel with application polypropylene pins Flex Point Neo was studied. Before sealing of root channela in laboratory model there was carried out within 7 day galvanophoresis of hydroxide cuprum-calcium with the help of invented by author's galvanic pins. Then channels were sealed up by material Dentalis KEZ with polypropylene pins. Methods of dye microinfiltration and scanning electronic microscopy revealed high efficacy of the specified way of endodontic treatments, consisting in good hermetic sealing system of root channels. In addition the autors defined, that temperature sterilization and efforts to bend did not cause essential deformation of pins and they corresponded to the ISO requirements.

Biocompatibility of different intracanal medications in rat bucal submucosa tissue.

The aim of this study was to analyze the buccal tissue responses of Wistar rats to 2% chlorhexidine solution, calcium hydroxide and the association of both products. For this purpose, 30 specimens were randomly implanted in the filtrum of the four upper and lower hemiarches with a polyethylene tube containing one of the following substances: 2% chlorhexidine solution, calcium hydroxide and 2% chlorhexidine solution (test groups); calcium hydroxide and distilled water and distilled water (control groups). Ten rats each were distributed according to time interval of evaluation at 7, 15 and 30 days. The histological sections were stained with Harris hematoxylin and eosin. Analysis was performed with an optical microscope at x100, x200 and x400 magnifications by an expert examiner blinded to the materials. The sections were classified by scores attributed to inflammatory events and by a ranking determined according to the severity of the inflammation. The results of the inflammatory events and severity ranking were submitted to the Kruskal-Wallis test at a 0.05 level of significance. No statistically significant difference occurred among the tested materials; however, all materials showed a decreased of severity with respect to longer time intervals.

Biocompatibility of different intracanal medications in rat bucal submucosa tissue

The aim of this study was to analyze the buccal tissue responses of Wistar rats to 2 percent chlorhexidine solution, calcium hydroxide and the association of both products. For this purpose, 30 specimens were randomly implanted in the filtrum of the four upper and lower hemiarches with a polyethylene tube containing one of the following substances: 2 percent chlorhexidine solution, calcium hydroxide and 2 percent chlorhexidine solution (test groups); calcium hydroxide and distilled water and distilled water (control groups). Ten rats each were distributed according to time interval of evaluation at 7, 15 and 30 days. The histological sections were stained with Harris hematoxylin and eosin. Analysis was performed with an optical microscope at x100, x200 and x400 magnifications by an expert examiner blinded to the materials. The sections were classified by scores attributed to inflammatory events and by a ranking determined according to the severity of the inflammation. The results of the inflammatory events and severity ranking were submitted to the Kruskal-Wallis test at a 0.05 level of significance. No statistically significant difference occurred among the tested materials; however, all materials showed a decreased of severity with respect to longer time intervals.