Research progress on biocomposites based on bioactive glass / 生物医学工程学杂志

Bioactive glass (BG) has been widely used in the preparation of artificial bone scaffolds due to its excellent biological properties and non-cytotoxicity, which can promote bone and soft tissue regeneration. However, due to the brittleness, poor mechanical strength, easy agglomeration and uncontrollable structure of glass material, its application in various fields is limited. In this regard, most current researches mainly focus on mixing BG with organic or inorganic materials by freeze-drying method, sol-gel method, etc., to improve its mechanical properties and brittleness, so as to increase its clinical application and expand its application field. This review introduces the combination of BG with natural organic materials, metallic materials and non-metallic materials, and demonstrates the latest technology and future prospects of BG composite materials through the development of scaffolds, injectable fillers, membranes, hydrogels and coatings. The previous studies show that the addition of BG improves the mechanical properties, biological activity and regeneration potential of the composites, and broadens the application of BG in the field of bone tissue engineering. By reviewing the recent BG researches on bone regeneration, the research potential of new materials is demonstrated, in order to provide a reference for future related research.

Anatomical post: a simple and safe alternative

Objective: To describe a clinical case that called for an anatomical post to be made to support and retain an indirect restoration in the anterior tooth. Case report: A 72-year-old female patient came to the office complaining that the crown of tooth 22 had come loose. A clinical and radiographic examination of element 22 was performed, and showed a very broad root canal, total displacement of the cast metal crown-core set, and satisfactory endodontic treatment. The restorative planning for this patient included the making of an anatomical post from Exacto # 2 fiberglass post (Angelus, Brazil), and refilling it with Bulk One composite resin (3M, USA), using self-adhesive resin cement U200 (3M, USA). The reconstruction of the coronary portion of the post was also performed with the same composite resin (Bulk One 3M, USA). The preparation for full crown and temporary restoration was performed in the same session, using self-curing acrylic resin. The all-ceramic crown was molded and cemented in subsequent sessions. Conclusion: The use of anatomical posts with composite resin represents a technically viable alternative for rehabilitating endodontically treated teeth with wide root canals, in cases where conventional prefabricated fiber posts cannot be adapted easily. The advantages that stand out are that these posts can be applied easily, at low cost, and in a single session.

Objetivo: Descrever um caso clínico de confecção do pino anatômico para suporte e retenção de restauração indireta em dente anterior. Relato do Caso: Paciente feminina, 72 anos, compareceu ao consultório queixando-se que a coroa do dente 22 havia "soltado". Realizou-se exame clínico e radiográfico do elemento 22, que apresentou conduto radicular bastante amplo, deslocamento total do conjunto núcleo/coroa e tratamento endodôntico satisfatório. O planejamento restaurador para essa paciente incluiu a confecção de pino anatômico, com pino de fibra de vidro Exato #2(Angelus, Brasil) reembasado com resina composta Bulk One (3M, EUA), utilizando o cimento resinoso autoadesivo U200 (3M, EUA). Foi realizada a reconstrução da porção coronária do pino também com resina composta do tipo Bulk. Realizou-se, na mesma sessão de atendimento, o preparo para coroa total e restauração provisória utilizando dente de estoque e resinaacrílica autopolimerizável. Em sessões seguintes foi realizada a moldagem e cimentação da coroa total em cerâmica pura. Conclusão: A utilização de pinos anatômicos com resina composta representa uma alternativa tecnicamente viável, de fácil aplicabilidade, com baixo custo e em única sessão, para reabilitação de dentes tratados endodonticamente com conduto radicular onde os pinos em fibra pré-fabricados convencionais não apresentam boa adaptação.

Do automotive window films affect drivers' safety by decreasing vision sensitivity? A Cross-sectional study / Películas automotivas e perda de acuidade visual? Estudo transversal

ABSTRACT Objective: To measure visual acuity in high contrast and low contrast sensitivities in different grades of visible light transmission films in three different positions (front, lateral and rear windows). Methods: Forty-four healthy volunteers between 30-75 y-o, with BCVA better than 0,5, were tested in the 5 following vehicles with different grades of visible light transmission films. Vehicle 1: 75% in the front and 70% in the lateral and rear windows; Vehicle 2: 70% in the front and lateral windows and 28% in the rear; Vehicle 3: 70% in the front, 28% in the lateral and 15% rear; Vehicle 4: 35% in all 3 windows; Vehicle 5: 50% in the front, 20% in the lateral and 15% in the rear. Descriptive statistics were used and the average of the 3 measurements of VA was considered. Wilcoxon Test was applied to compare the average visual acuity in each vehicle and position. P value<0.05 was considered statistically significant. Results: According to the Brazilian Traffic Regulations for driving in categories C/D/E, when low contrast was tested in the front window, all visible light transmissions were borderline, in the lateral window they were all outside the limit, while in the rear window for both low and high contrast, all visible light transmissions tested were outside the limit and also borderline for driving in categories A/B, with the exception of the vehicle with visible light transmission of 35%. Conclusion: Visual acuity is affected, especially in the rear window, by the use of automotive films. The study is an alert that window films is a possible cause of accidents and may contribute to the revision of traffic regulations worldwide.

RESUMO Objetivo: Medir a acuidade visual em alto e baixo contraste nas diversas graduações de transparência de filmes em três janelas de veículos: frontal, lateral e traseira. Métodos: Foram avaliados 44 voluntários saudáveis entre 30 e 75 anos, com acuidade visual melhor corrigida acima de 0,5, em cinco veículos, sendo: veículo 1, com 75% de transparência frontal e 70% na lateral e traseira; veículo 2, com 70% na frontal e na lateral e 28% na traseira; veículo 3, com 70% na frontal, 28% na lateral e 15% na traseira; veículo 4, com 35% nas três janelas; e veículo 5, com 50% na frontal, 20% na lateral e 15% na traseira. Foi realizada estatística descritiva utilizando a média de três medidas consecutivas, com teste de Wilcoxon para comparar a média de acuidade visual em cada janela, e foi considerado estatisticamente significativo quando valor de p<0,05. Resultados: Todas as transparências testadas nos vidros reduziram a acuidade visual em situação de baixo contraste para níveis limítrofes na janela frontal e níveis ilegais na lateral para conduzir veículos nas categorias C/D/E. Na janela traseira, tanto em alto quanto em baixo contraste, todas as transparências mostraram redução da acuidade visual para níveis ilegais para categorias C/D/E e limítrofes para as categorias A/B, exceto na transparência de 35%. Conclusão: A acuidade visual é reduzida pelo uso dos filmes automotivos, especialmente na janela traseira. Condutores de veículos com filmes devem ser alertados pelo risco aumentado de acidentes. Esse dado científico propõe revisões nas regulações de tráfego mundiais.

Higienización y eliminación fúngica en instalaciones industriales para la disminución de riesgos ocupacionales / Sanitization and fungal elimination in industrial facilities to reduce occupational risks

Se ha comprobado que la exposición a bioaerosoles se asocia con varios efectos sobre la salud, como enfermedades pulmonares y alergias. El presente estudio transversal tuvo como objetivo investigar la contaminación por hongos en varias superficies pertenecientes a dos industrias de alimentos. La toma de muestra se realizó en tres semanas, inmediatamente después de realizada la limpieza y desinfección y antes de iniciar la producción. Se recolectaron 400 muestras de superficie (vidrio, acero inoxidable, aluminio, goma y plástico), también se evaluó la eficacia del programa de higienización en el control de la población de hongos. Todas las muestras presentaron recuentos fúngicos <10 ufc/cm2, sin haber diferencias significativas entre los tipos de superficie, sin embargo, las superficies plásticas exhibieron mayor crecimiento logarítmico de los hongos. Se determinó que 49,60% de las especies identificadas correspondieron al género Penicillium. Aunque los niveles de hongos en las industrias estudiadas fueron inferiores a los niveles recomendados por la Organización Mundial de la Salud, algunas medidas de salud ambiental como lavar y desinfectar las superficies después de cada turno de trabajo, y se recomiendan inspecciones periódicas para garantizar la seguridad de los trabajadores y de los productos que allí se manufacturan(AU)

It has been proven that exposure to bioaerosols is associated with several health effects, such as pulmonary diseases and allergies. The present crosssectional study aimed to investigate fungal contamination on various surfaces belonging to two food industries. The sampling was carried out in three weeks, immediately after cleaning and disinfection and before starting production. 400 surface samples were collected (glass, stainless steel, aluminum, rubber and plastic), the effectiveness of the sanitation program in controlling the fungal population was also evaluated. All the samples presented fungal counts <10 cfu / cm2, with no significant differences between the types of surfaces, however, the plastic surfaces exhibited higher logarithmic growth of the fungi. It was determined that 49.60% of the identified species corresponded to the Penicillium genus.Although the levels of fungi in the studied baths were lower than the levels recommended by the World Health Organization, some environmental health measure ssuch as washing and disinfecting surfaces after each working shift and periodic inspections are recommended ensuring the safety of the workers and the products that are manufactured there(AU)

Saneamiento industrial: Biodisponibilidad de patógenos en superficies / Industrial sanitation: Bioavailability of pathogens on surfaces

En condiciones adecuadas como humedad, alcalinidad, o temperatura, determinados patógenos logran adherirse a las superficies y sobrevivir ciertos períodos fuera de un anfitrión, persistiendo en algunos casos a procesos deficientes de limpieza y desinfección, configurándose como un posible foco de transmisión. Por ello, el correcto saneamiento cumple un propósito vital en la protección de los trabajadores de la industria y otros sectores frente al riesgo de contaminación por contacto directo con las superficies contaminadas. La literatura científica muestra amplia evidencia de la supervivencia de patógenos sobre superficies que son habituales dentro de instalaciones industriales, como acero, aluminio, madera, plástico y vidrio. La supervivencia de microorganismos en las superficies puede configurarse como candidato a marcador de biodisponibilidad, que puede ser usado en la industria para establecer y auditar los planes de higienización y saneamiento industrial, permitiendo estudiar la eficacia de los compuestos usados en la desinfección, y variables como su concentración, temperatura, e intervalos de aplicación y remoción(AU)

Under suitable conditions such as humidity, alkalinity, or temperature, certain pathogens manage to adhere to surfaces and survive certain periods outside of a host, persisting in some cases to poor cleaning and disinfection processes, becoming a possible source of transmission. Therefore, proper sanitation serves a vital purpose in protecting workers in industry and other sectors from the risk of contamination by direct contact with contaminated surfaces. The scientific literature shows ample evidence of the survival of pathogens on surfaces that are common within industrial facilities, such as steel, aluminum, wood, plastic and glass. The survival of microorganisms on surfaces can be configured as a candidate for bioavailability marker, which can be used in the industry to establish and audit industrial sanitation and sanitation plans, allowing to study the efficacy of the compounds used in disinfection, and variables such as its concentration, temperature, and application and removal intervals(AU(

Lavagem, preparo e esterilização de materiais / Lavado, preparación y esterilización de materiales / Washing, preparation and sterilization of materials

Esta Norma Técnica tem por objetivo estabelecer os critérios para lavagem, preparo e esterilização de vidrarias e materiais utilizados nos processos de manipulação e controle da qualidade do leite humano ordenhado, visando a garantia da qualidade em Bancos de Leite Humano e Postos de Coleta de Leite Humano e sua certificação.

Esta Norma Técnica tiene por objetivo establecer los criterios de lavado, preparación y esterilización de la vidriería y materiales utilizados en los procesos de manipulación y control de calidad de la leche humana extraída, con el fin de asegurar la calidad en los Bancos de Leche Humana y Centros de Recolección de Leche Humana y su certificación.

Influence of testing environment on static fatigue behavior of a glass and a polycrystalline ceramic

Abstract It aims on evaluate the effect of the test environment on static fatigue behavior of lithium disilicate-based (LD), and yttrium oxide-stabilized zirconia (YSZ) ceramics. Specimens of LD (IPS e.max CAD, Ivoclar Vivadent) and YSZ (IPS e.max ZirCAD MO, 3 mol% Y2O3, Ivoclar Vivadent) were randomly allocated into three groups: tested in air, inert (paraffin oil, Sigma Aldrich) or distilled water. The static fatigue test (n=15) was performed using a piston-on-three ball assembly, adapted from ISO 6872, as follows: starting load 100 N for LD and 300 N for YSZ; loading application time set to 1 hour for each loading step; step size of 50 N for LD and 100 N for YSZ, applied successively until fracture. Data from static fatigue strength (MPa) and time to fracture (hours) were recorded. Fractographic analysis was executed. Survival analysis corroborates absence of influence of environment on static fatigue outcomes (fatigue strength, time to fracture and survival rates) for YSZ. For LD, specimens tested in air presented statistically superior survival rate and static fatigue strength (p= 0.025). In regards of time to fracture, LD tested in air were superior than when tested in distilled water (p=0.019) or inert (p=0.017) environments. No statistical differences for Weibull modulus were observed. Failures started on the tensile stress surface. Thus, the test environment did not affect slow crack growth (SCG) mechanisms during static fatigue test of YSZ ceramics, but it plays a significant role for the static fatigue behavior of lithium disilicate-based glass ceramics, indicating a high susceptibility to SCG.

Resumo O presente estudo objetivou investigar a influência do ambiente de teste no comportamento a fadiga estática (resistência à fratura e tempo para falha) de cerâmicas à base de dissilicato de lítio (LD) e zircônia estabilizada com ítria (YSZ). Espécimes de LD (IPS e.max CAD, Ivoclar Vivadent) e YSZ (IPS e.max ZirCAD MO, 3mol% Y2O3, Ivoclar Vivadent) foram obtidos e alocados aleatoriamente em três grupos: testado em ar, em líquido inerte (óleo de parafina) ou em água destilada. O teste de fadiga estática (n= 15) foi realizado usando o teste pistão sobre três esferas, ISO 6872, da seguinte forma: carga inicial 100 N para LD e 300 N para YSZ; tempo de aplicação de carregamento definido para 1 hora para cada etapa de carregamento; tamanho do passo de 50 N para LD e 100 N para YSZ, aplicados sucessivamente até a fratura. Dados de resistência à fadiga estática (MPa) e tempo até a fratura (horas) foram registrados. A análise fractográfica foi executada. A análise de sobrevivência corrobora a ausência de influência do ambiente de teste nos resultados de fadiga estática (resistência à fadiga, tempo de fratura e taxas de sobrevivência) para a YSZ. Para LD, os corpos de prova testados em ar apresentaram taxa de sobrevivência e resistência à fadiga estática estatisticamente superiores (p= 0,025). Em relação ao tempo de fratura, os espécimes LD testados em ar foram superiores aos testados em água destilada (p= 0,019) ou em ambiente inerte (p= 0,017). Não foram observadas diferenças estatísticas para o módulo de Weibull. Todas as falhas começaram no lado onde se concentra a tensão de tração (lado de baixo) durante o teste. Com base nisso, observa-se que o ambiente de teste não afetou os mecanismos de crescimento lento de trinca durante o teste de fadiga estática da cerâmica YSZ, mas desempenha um papel significativo na resistência à fadiga estática da cerâmica de vidro à base de dissilicato de lítio, indicando alta susceptibilidade ao crescimento lento e subcrítico de trincas.

Neumonía por Pneumocystis Jirovecii en paciente adolescente inmunosuprimido no VIH positivo: Un reporte de caso / Pneumocystis Jirovecii pneumonia in a non-HIV immunosuppressed adolescent patient: A case report

Resumen La neumonía en el paciente inmunocomprometido es un reto diagnóstico al cual el clínico se enfrenta cada vez con más frecuencia , al momento de hablar de infiltrados en vidrio esmerilado es menester tener siempre en cuenta la posibilidad de neumonía por Pneumocystis Jirovecii, que por mucho tiempo se pensó como una enfermedad propia del huésped inmunosuprimido con VIH, a través del tiempo se ha manifestado en pacientes con trasplantes de órgano sólido y de precursores hematopoyéticos, asociado a autoinmunidad, al uso crónico de corticoesteroides y más recientemente al uso de terapia biológicas. La descripción de esta enfermedad y sus métodos diagnósticos en huéspedes inmunosuprimidos no VIH no es del todo claro, sabemos que el tratamiento de elección en estos casos es el trimetropin-sulfametoxazol (TMP-SMX) el cual no cuenta con evidencia de alta calidad al momento de plantear una dosis ni un tiempo de duración establecidos. Presentamos el caso de un paciente con diagnóstico de glomerulonefritis por enfermedad de cambios mínimos corticodependiente y quien desarrolló neumonía por Pneumocystis Jirovecii confirmada por histopatología quien recibió tratamiento y tuvo un desenlace positivo.

Abstract The pneumonia in the immunocompromised patient is a diagnostic challenge that the clinician faces more and more frequently, every time we talk about ground glass infiltrates it is necessary to always take into account the possibility of pneumonia due to Neumocystis Jirovecii, which for a long time was thought as a disease of the immunosuppressed host with HIV, but that across the time it has manifested itself in patients with solid organ transplants and hematopoietic precursors, associated with autoimmunity, the chronic use of corticosteroids and more recently the use of biological therapy. The description of this disease and the diagnostic methods in non-HIV immunosuppressed hosts is not entirely clear, we know that the treatment of choice in these cases is trimethropin-sulfamethoxazole (TMP-SMX), which does not have high-quality evidence at the time of a dose or a time of established duration. We present the case of a patient diagnosed with glomerulonephritis due to corticodependent minimal change disease and who suffers from pneumocystis Jirovecii pneumonia confirmed by histopathology, which received treatment and had a positive outcome

Reparative regeneration by substitution of bone tissue defects with bioglass, using regeneration technologies / Regeneración reparadora mediante sustitución de defectos del tejido óseo por biovidrio, utilizando tecnologías de regeneración

SUMMARY: Bioactive glass (BG) induces osteogenesis of damaged bone, causing excessive bone formation. This study included a morphological and morphometrical data of the bone tissue regeneration by filling bone defects with BG with autologous native platelet rich plasma (PRP) or fibrin (PRF) and aspirate of bone marrow (ABM). The parameters of newly formed bone in rabbits bone defect were analyzed and compared with terms 4th and 12th week. The groups with ABM-BG, PRF-BG and PRP-BG have shown common tendency: development of newly formed bone tissue, the external contour of the bone has been enlarged; an additional trabecular bone has been formed under the cortical layer, which has often been limited by a solid compact bone from the bone marrow. The induced osteogenesis resulted in the appearance of a significant amount of bone tissue exceeding the original size of the defect. Increased density of the newly formed tissue at the defect level relative to ABM-BG was detected in the PRF-BG group at 12 weeks and PRP-BG at 4 and 12 weeks (p<0.05). In this case, the bone thickness in the substituted defect was greater in the ABM-BG group. The number of newly formed bone tissue in the ABM-BG group at 4 weeks also exceeded the value of the BG group, but the density of such bone did not differ between the groups. That is, ABM-BG stimulated greater trabecular bone formation and fibrous reticular tissue was located in the lacunae between trabeculae. These results indicate that the additional use of tissue technology (ABM, platelet plasma) facilitated osteogenesis, and the newly formed bone tissue was tightly coupled and remodeled to the cortical bone layer in the form of compact bone tissue. PRP, to a greater extent than ABM, promoted the formation of compact bone tissue.

RESUMEN: El vidrio bioactivo (VB) induce la osteogénesis del hueso dañado, provocando una formación excesiva de hueso. Este estudio incluyó datos morfológicos y morfométricos de la regeneración del tejido óseo mediante el llenado de defectos óseos con VB con plasma rico en plaquetas (PRP) nativo autólogo o fibrina (PRF) y aspirado de médula ósea (AMO). Se analizaron los parámetros de hueso recién formado en el defecto óseo de conejos y se compararon a las 4 y 12 semanas. Se observó una tendencia similar en los grupos con AMO-VB, PRF-VB y PRP-VB: el desarrollo de tejido óseo recién formado, aumentó el contorno externo del hueso; formación de un hueso trabecular adicional debajo de la capa cortical, que a menudo ha estado limitada por un hueso sólido compacto de la médula ósea. La osteogénesis inducida dio como resultado la aparición de una cantidad significativa de tejido óseo que excedía el tamaño original del defecto. Se detectó un aumento de la densidad del tejido recién formado a nivel del defecto en relación con AMO-VB en el grupo PRF-VB a las 12 semanas y PRP-VB a las 4 y 12 semanas (p <0,05). En este caso, el grosor óseo en el defecto sustituido fue mayor en el grupo AMO-VB. El número de tejido óseo recién formado en el grupo AMO- VB a las 4 semanas también excedió el valor del grupo VB, pero la densidad de dicho hueso no cambió entre los grupos. Es decir, AMO-VB estimuló una mayor formación de hueso trabecular y se localizó en el tejido reticular fibroso en las lagunas entre trabéculas. Estos resultados indican que el uso adicional de tecnología de tejidos (AMO, plasma plaquetario) facilitó la osteogénesis, y el tejido óseo recién formado se acopló y remodeló estrechamente a la capa de hueso cortical en forma de tejido óseo compacto. El PRP, en mayor medida que el AMO, promovió la formación de tejido óseo compacto.

Effect of the application of different concentrations of Edta on the adhesion of fiber posts using self-adhesive cements

Abstract The purpose of this study was to analyze the effect of the application of different concentrations of EDTA on the adhesion of fiber posts to root dentin using self-adhesive resin cements. After endodontic treatment, 78 single roots were randomly divided into six groups (n = 13) according to the combination of the following factors: surface dentin treatment - control (distilled water), 17% EDTA and 24% EDTA; and self-adhesive resin cement - RelyX U200 (RX); and Multilink Speed (ML). After fiber post cementation, six slices were obtained for each root. Ten roots of each group were used for bond strength (BS) and three for microhardness (MH) evaluations. Data obtained from BS and MH tests for each resin cement were subjected to two-way ANOVA (surface treatment vs. root region) and to a post-hoc Tukey's test (α = 0.05). The lowest BS value was observed in the 24% EDTA group for RX cement, whereas the highest values for ML cement were observed for the control group in the middle and apical regions. In the MH test, the lowest value for RX was observed for 24% EDTA in the cervical region, whereas and the highest value for the ML cement was observed in the control group. Regarding both self-adhesive resin cements tested, the application of 24% EDTA was not able to improve the adhesion of fiber posts to root canal.

Effect of S53P4 bioactive glass and low-level laser therapy on calvarial bone repair in rats submitted to zoledronic acid therapy

ABSTRACT Purpose To evaluate the influence of bioactive glass and photobiomodulation therapy (PBMT) in calvarial bone repair process in rats submitted to zoledronic acid therapy. Methods Twenty-four rats were selected and treated with the dose of 0.035 mg/kg of zoledronic acid every two weeks, totalizing eight weeks, to induce osteonecrosis. After the drug therapy, surgical procedure was performed to create 5-mm diameter parietal bone defects in the calvarial region. The rats were then randomly assigned to groups according to the following treatments: AZC: control group, treated with blood clot; AZBIO: bone defect filled with bioactive glass; AZL: treated with blood clot and submitted to PBMT; and AZBIOL: treated with bioactive glass S53P4 and submitted to PBMT. Tissue samples were collected and submitted to histomorphometric analysis after 14 and 28 days. Results At 14 days, bone neoformation in the AZBIO (52.15 ± 9.77) and AZBIOL (49.77 ± 13.58) groups presented higher values (p ≤ 0.001) compared to the AZC (23.35 ± 10.15) and AZL groups (23.32 ± 8.75). At 28 days, AZBIO (80.24 ± 5.41)still presented significant higher bone recovery values when compared to AZC (59.59 ± 16.92)and AZL (45.25 ± 5.41) groups (p = 0.048). In the 28-day period, the AZBIOL group didn't show statistically significant difference with the other groups (71.79 ± 29.38). Conclusions The bioactive glass is an effective protocol to stimulate bone neoformation in critical defects surgically created in rats with drug induced osteonecrosis, in the studied periods of 14 and 28 days.

Influência do tipo de cimento endodôntico na adesão de pinos de fibra de vidro: revisão de literatura / Influence of the type of endodontic sealer on glass fiber post adhesion: literature review

Introdução: Pinos de fibra de vidro são bastante utilizados quando dentes tratados endodonticamente apresentam grande perda estrutural e necessitam de suporte para a sua reconstrução coronária. A completa adesão do pino à parede do canal radicular é fundamental para o sucesso dessa restauração. Resíduos de cimento endodôntico que permanecem nas paredes dentinárias, mesmo após o preparo para a cimentação, podem interferir negativamente na sua adesão e contribuir para o seu deslocamento. Objetivo: O objetivo da presente revisão de literatura foi avaliar o efeito de diferentes cimentos endodônticos e o tempo decorrido entre a obturação e a cimentação do pino na resistência de união entre o pino e a parede do canal radicular. Métodos: Essa revisão de literatura incluiu 21 estudos que analisaram a influência de cimentos endodônticos na adesão de pinos de fibra de vidro, entre os quais 9 acrescentaram a variável tempo na sua análise, com pinos cimentados logo após a obturação do canal radicular e dias após a obturação. Resultados: Os dentes obturados com cimentos à base de resina demonstraram maior resistência ao deslocamento dos pinos durante os testes. Parece haver uma predominância de menores valores de adesão quando os pinos são cimentados imediatamente após a obturação com cimentos contendo eugenol. Conclusões: Os tipos de cimento endodôntico e o período entre a obturação e a cimentação do pino podem afetar a força de ligação entre a parede do canal radicular e o pino de fibra de vidro (AU).

ntroduction: Glass fiber posts are widely used when endodontically treated teeth present great structural loss and require support for coronal reconstruction. Complete adhesion of the post to the root canal wall is fundamental for the success of this restoration. Endodontic sealer residues that remain on the dentin walls, even after preparation for cementation, may negatively interfere with the adhesion and contribute for post displacement. This literature review evaluated the effect of different endodontic sealers and the time between obturation and post cementation on the bond strength. Methods: This literature review included 21 studies that analyzed the influence of endodontic sealers on the adhesion of glass fiber posts, among which 9 added the variable time in their analysis. Results: Teeth filled with resin-based sealers showed higher post push-out bond strength during testing. There seems to be predominance of lower adhesion values when the posts are cemented immediately after filling with eugenol-containing sealers. Conclusions: The type of endodontic sealer and period between obturation and post cementation can affect the bond strength between root canal wall and the glass fiber post(AU).

Influence of sonic vibration and cement type on the bond strength of fiberglass posts after aging / Influencia de la vibración sónica y el tipo de cemento en la fuerza de unión de los postes de fibra de vidrio después del envejecimiento

Introduction: This study evaluated the influence of sonic vibration and thermocycling on the bond strength of fiberglass posts using conventional dual-cured and self-adhesive resin cements. Material and Methods: Ninety-six single-rooted endodontically treated teeth were divided randomly into eight groups according to the cement used (dual-cured or self-adhesive resin cement), use of sonic vibration during post accommodation, and aging conditions (24h in distilled water or 5,000 thermal cycles). The fiberglass posts (White Post DC1, FGM) were cleaned with alcohol, treated with silane and cemented with dual-cured (Allcem Core, FGM) or with self-adhesive resin cement (seT, SDI). For groups in which sonic vibration was used, the posts were accommodated, and sonic vibration was applied for 10 s using a special tip placed on top of the post (Sonic Smart Device, FGM). Pull-out tests were performed after storage in distilled water for 24h at 37°C or after thermocycling (5000 cycles, at 5°C and 55°C). The results were evaluated using three-way ANOVA and Tukey's test (α=0.05). Results: Significant differences were not observed between the bond strengths of dual-cured (87.93±41.81 N) and self-adhesive cement (82.53±41.43 N). Bond strength for the sonic vibration groups (100.36±42.35 N) was significantly higher than for groups without sonic vibration (70.13±34.90 N). There were significant differences between specimens subjected to thermocycling (98.33±39.42 N) and those stored for 24h in distilled water (72.16±39.67 N). Conclusion: It can be concluded that both sonic vibration and thermocycling significantly improved bond strength of fiberglass posts with the two evaluated resin cements.

Introducción: Este estudio evaluó la influencia de la vibración sónica y el termociclado en la fuerza de unión de los postes de fibra de vidrio utilizando cementos de resina autoadhesivos y de curado dual convencionales Material y Métodos: Se dividieron aleatoriamente noventa y seis dientes tratados endodónticamente de raíz única en ocho grupos según el cemento utilizado (cemento de resina de curado dual o autoadhesivo), el uso de vibración sónica durante la acomodación posterior y las condiciones de envejecimiento (24 horas agua destilada o 5.000 ciclos térmicos). Los postes de fibra de vidrio (White Post DC1, FGM) se limpiaron con alcohol, se trataron con silano y se cementaron con cemento de curado dual (Allcem Core, FGM) o con cemento de resina autoadhesivo (seT, SDI). Para los grupos en los que se utilizó vibración sónica, se acomodaron los postes y se aplicó la vibración sónica durante 10 s utilizando una punta especial colocada en la parte superior del poste (Sonic Smart Device, FGM). Las pruebas de extracción se realizaron después del almacenamiento en agua destilada durante 24 horas a 37ºC o después del termociclado (5000 ciclos, a 5ºC y 55ºC). Los resultados se evaluaron mediante ANOVA de tres vías y la prueba de Tukey (α = 0.05). Resultados: No se observaron diferencias significativas entre las resistencias de adhesión del cemento de curado dual (87,93 ± 41,81 N) y el cemento autoadhesivo (82,53 ± 41,43 N). La fuerza de unión para los grupos de vibración sónica (100,36 ± 42,35 N) fue significativamente mayor que para los grupos sin vibración sónica (70,13 ± 34,90 N). Hubo diferencias significativas entre los especímenes sometidos a termociclado (98,33 ± 39,42 N) y los almacenados durante 24 h en agua destilada (72,16 ± 39,67 N). Conclusión: Se puede concluir que tanto la vibración sónica como el termociclado mejoraron significativamente la fuerza de unión de los postes de fibra de vidrio con los dos cementos de resina evaluados.

Biocerámicos: aspectos farmaco-tecnológicos y clínicos de uso odontológico / Bioceramics: pharmatechnological and clinical aspects of dental use

Se analizan aspectos fármaco-tecnológicos y clínicos de biocerámicos bioabsorbibles compuestos por biovidrios con capacidad osteogénica y microbicida, para ser utilizados como relleno bioactivo en el conducto radicular y como tratamiento terapéutico en el sitio de a lesión apicoperirradicular de origen endodóntico. Mediante un diagrama ternario se consideraron las diversas variables cuyos valores determinan las diferentes fases de los vidrios bioactivos, hasta alcanzar la formación de hidroxiapatita, cuando se someten a un medio biológico. Se analizaron composición y mecanismo de acción en la reparación posendodóntica, que parte de la integración del biomaterial al tejido duro sano, sin formación de fibrosis o proceso inflamatorio inmune (AU)

Pharmacotechnological and clinical aspects of bioabsorbable bioceramics composed of bioglasses with osteogenic and microbicidal capacity are analyzed, to be used as a bioactive filler in the root canal and as a therapeutic treatment at the site of an apicoperiradicular lesion of endodontic origin. By means of a ternary diagram, the various variables whose values determine the different phases of the bioactive glasses were considered, until reaching the formation of hydroxyapatite, when subjected to a biological medium. Composition and mechanism of action were analyzed in post-endodontic repair, which starts from the integration of the biomaterial into healthy hard tissue, without the formation of fibrosis or an immune inflammatory process (AU)

Avaliação da citotoxicidade e resposta tecidual de soluções irrigadoras experimentais a partir de biovidro e biovidro modificado com cobalto / Evaluation of cytotoxicity and tissue response of experimental irrigating solutions from bioglass and bioglass modified with cobalt

Introdução: Novas formulações de materiais vítreos apresentaram atividade antimicrobiana e osteoindutora. Objetivos: O objetivo deste estudo foi avaliar a citotoxicidade e a biocompatibilidade de soluções produzidas a partir de novas formulações de biovidros, o F18 (biovidro experimental) e o F18 com Cobalto (F18-Co; biovidro experimental dopado com cobalto), comparadas à água de cal, obtida a partir de solução com hidróxido de cálcio (Ca(OH)2). Material e métodos: O F18 foi preparado e moído, e parte deste foi dopada com cobalto. As soluções foram preparadas com cada material (1:10 de pó para água), formando os grupos F18, F18-Co e Ca(OH)2. Células L929 foram cultivadas, e a viabilidade celular avaliada a partir das soluções e de suas diluições (½, », 1/8 e 1/16 diluição) pelo teste MTT, após 24 e 48 horas. Para avaliar a biocompatibilidade, tubos de polietileno foram preenchidos com esponjas de fibrina embebidas nas soluções não diluídas, e tubos embebidos em soro fisiológico serviram de controle. Os tubos foram implantados no dorso de 16 ratos. Após 7 e 30 dias (n = 8), os ratos foram eutanasiados, e os tubos com o tecido circundante foram processados para coloração de hematoxilina-eosina (H.E.) e análise da inflamação através de escores. Os dados paramétricos (citotoxicidade) foram submetidos aos testes de normalidade para definir o teste estatístico a ser empregado, e os dados não-paramétricos (H.E.), foram avaliados pelos testes de Kruskal Wallis e Dunn (p < 0,05). Resultados: As soluções não diluídas dos materiais, e as diluições de ½ e », reduziram a viabilidade celular em 24 h (p < 0,05). As diluições de 1/8 e 1/16 do F18 e F18Co apresentaram viabilidade celular semelhante ao controle (p > 0,05), o que não ocorreu com Ca(OH)2 (p < 0,05), que foi citotóxico. Em 48 h, apenas as soluções não diluídas e diluições de ½ e » do F18 foram similares ao controle (p > 0,05), e as demais foram citotóxicas. Mas as diluições de 1/8 e 1/16 do F18Co teve um aumento na viabilidade celular comparadas às soluções do Ca(OH)2 (p < 0,05), e foram semelhantes ao controle (p > 0,05). Aos 7 dias, controle, F18 e F18-Co apresentaram inflamação moderada, e Ca(OH)2, severa (p > 0,05); a cápsula fibrosa foi espessa. Aos 30 dias, controle e F18-Co apresentaram inflamação leve comparados ao F18, com inflamação moderada (p < 0,05); Ca(OH)2 teve inflamação leve ( p > 0,05); a cápsula fibrosa foi fina na maior parte dos espécimes . Conclusões: Soluções experimentais de F18 e F18 dopado com cobalto são citocompatíveis, diferentemente da solução de Ca(OH)2; todas as soluções apresentaram biocompatibilidade(AU)

Introduction: New formulations of vitreous materials showed antimicrobial and osteoinductive activity. Objectives: The aim of this study was to evaluate the cytotoxicity and biocompatibility of solutions produced from new formulations of bioglass, F18 (experimental bioglass) and F18 with Cobalt (F18-Co; experimental bioglass doped with cobalt), compared to lime water, obtained from a solution with calcium hydroxide (Ca(OH)2). Material and methods: The F18 was prepared and ground, and part of it was doped with cobalt. The solutions were prepared with each material (1:10 powder to water), forming groups F18, F18-Co and Ca(OH)2. L929 cells were cultured, and cell viability assessed from solutions and from its dilutions (½, », 1/8 and 1/16 dilution) by the MTT test, after 24 and 48 hours. For biocompatibility analysis, polyethylene tubes were filled with fibrin sponges embedded in the non-diluted solutions, and tubes embedded in saline solution served as controls. The tubes were implanted on the dorsum of 16 rats. After 7 and 30 days (n = 8), the rats were euthanized, and the tubes with the surrounding tissue were processed for staining of hematoxylin-eosin (H.E.) and analysis of inflammation through scores. The parametric data (cytotoxicity) were subjected to normality tests to define the statistical test to be used, and the nonparametric data (H.E.), were evaluated by the Kruskal Wallis and Dunn tests (p < 0.05). Results: Undiluted solutions of the materials, and dilutions of ½ and », reduced cell viability in 24 h (p < 0.05). The 1/8 and 1/16 dilutions of F18 and F18-Co showed cell viability similar to the control (p > 0.05), which did not occur with Ca(OH)2 (p <0.05), which was cytotoxic. At 48 h, only undiluted solutions and dilutions of ½ and » of F18 were similar to the control (p > 0.05), and the others were cytotoxic. However, the 1/8 and 1/16 dilutions of F18-Co had an increase in cell viability compared to Ca(OH)2 solutions (p <0.05), and were similar to the control (p > 0.05). At 7 days, control, F18 and F18-Co showed moderate inflammation, and Ca(OH)2, severe (p > 0.05); the fibrous capsule was thick. At 30 days, control and F18-Co showed mild inflammation compared to F18, with moderate inflammation (p < 0.05); Ca(OH)2 had mild inflammation (p > 0.05); the fibrous capsule was thin in most specimens. Conclusions: Experimental solutions of F18 and F18 doped with cobalt are cytocompatible, unlike the Ca(OH) 2 Keywords: solution; all solutions showed biocompatibility(AU)

Experimental gel containing bioactive glass-ceramic to minimize the pulp damage caused by dental bleaching in rats

Abstract Objectives This study evaluated if the use of a bioactive glass-ceramic-based gel, named Biosilicate (BS), before, after or mixed with bleaching gel, could influence the inflammation of the dental pulp tissue of rats' molars undergoing dental bleaching with hydrogen peroxide (H2O2). Methodology The upper molars of Wistar rats (Rattus norvegicus, albinus) were divided into Ble: bleached (35% H2O2, 30-min); Ble-BS: bleached and followed by BS-based gel application (20 min); BS-Ble: BS-based gel application and then bleaching; BS/7d-Ble: BS-based gel applications for 7 days and then bleaching; Ble+BS: blend of H2O2 with BS-based gel (1:1, 30-min); and control: placebo gel. After 2 and 30 days (n=10), the rats were euthanized for histological evaluation. The Kruskal-Wallis and Dunn statistical tests were performed (P<0.05). Results At 2 days, the Ble and Ble-BS groups had significant alterations in the pulp tissue, with an area of necrosis. The groups with the application of BS-based gel before H2O2 had moderate inflammation and partial disorganization in the occlusal third of the coronary pulp and were significantly different from the Ble in the middle and cervical thirds (P<0.05). The most favorable results were observed in the Ble+BS, which was similar to the control in all thirds of the coronary pulp (P>0.05). At 30 days, the pulp tissue was organized and the bleached groups presented tertiary dentin deposition. The Ble group had the highest deposition of tertiary dentin, followed by the Ble-BS, and both were different from control (P<0.05). Conclusion A single BS-based gel application beforehand or BS-based gel blended with a bleaching gel minimize the pulp damage induced by dental bleaching.

Effect of ethanol-wet bonding on porosity and retention of fiberglass post to root dentin

Abstract: This in vitro study aimed to assess the effects of different pretreatments used to adapt glass-fiber posts cemented to root canals with different resin cements, regarding porosity percentage and bond strength. Twelve bovine incisor roots were prepared with Largo drills. After post space preparation, the specimens were randomized into two types of pretreatment groups (n = 3): water-wet bonding and ethanol-wet bonding. After the post were cemented, the roots were stored in 100% humidity at room temperature for 7 days. The samples were scanned by microcomputed tomography (micro-CT). Images were reconstructed by NRecon software, and CTAn software was used to analyze the porosity percentage (%) at the luting interface. Evaluation of the push-out bond strength was performed by serially cutting the roots, and submitting the slices to testing. Additionally, the resin cement post-gel shrinkage values (%) were measured using the strain-gauge method (n = 10). Data were analyzed by two-way ANOVA, Tukey's test and Student's t test (a = 0.05). The roots prepared with ethanol-wet bonding using RelyX™ U200 had significantly lower porosity in the coronal and apical thirds (p < 0.05). The group prepared with ethanol-wet bonding using RelyX™ ARC presented better bond strength results in the coronal and apical thirds (p < 0.05). RelyX™ ARC (0.97%) produced a higher post-gel shrinkage value than RelyX™ U200 (0.77%). Canals pretreated with ethanol-wet bonding presented better outcomes in regard to porosity percentage and push-out bond strength.

Papel de distintas técnicas de imagen para identificar y localizar cuerpos extraños intraoculares relacionados con trauma ocular abierto: reporte de tres casos y revisión de la literatura / The role of various imaging techniques in identifying and locating intraocular foreign bodies related to open-globe injury: three case reports and literature review

ANTECEDENTES La ubicación precisa de un cuerpo extraño intraocular es crucial para el manejo de pacientes con trauma ocular abierto. La tomografía computarizada se usa habitualmente para detectar su ubicación en el segmento posterior. Reportamos tres casos con diferentes cuerpos extraños intraoculares en el segmento posterior, que fueron localizados con precisión mediante la tomografía computarizada y ecografía modo B. PRESENTACIÖN DEL CASO Presentamos tres casos con diferentes mecanismos de trauma, tipos de cuerpo extraño intraocular, síntomas clínicos y pronóstico visual. La tomografía computarizada determinó la ubicación exacta de todos los cuerpos extraños intraoculares en el segmento posterior. El ultrasonido modo B se realizó en un paciente con un cuerpo extraño intraocular no metálico. El primer caso tuvo una lesión ocular perforante con un cuerpo extraño intraorbitario; el caso dos y el caso tres presentaron diferentes tipos de cuerpos extraños intraoculares con pronóstico diferente. El manejo y el pronóstico fue distinto en todos los casos; todos se manejaron con éxito. La ubicación exacta de los cuerpos extraños intraoculares utilizando las diferentes modalidades de diagnóstico es importante en estos pacientes. Estos casos sirven como recordatorio de que el uso adecuado de las pruebas de imagen es indispensable en el contexto de un cuerpo extraño intraocular relacionado con trauma ocular abierto. CONCLUSIÓN Las diferentes técnicas de imágenes son muy importantes para la detección de un cuerpo extraño intraocular. La tomografía computarizada es una de las modalidades de imagen más simple y efectiva para la localización de cuerpos extraños intraoculares relacionadas con trauma ocular abierto.

BACKGROUND: Determining the precise location of intraocular foreign bodies is crucial for the management of patients with open-globe injury. Computed tomography is the most common method for detecting intraocular foreign bodies in the posterior segment. In this article, we describe three cases of open-globe injury with different types of intraocular foreign bodies in the posterior segment that were accurately located using computed tomography scans and B-scan ultrasonography. CASE PRESENTATION: Each of the three cases of open-globe injury described in this report had different types of ocular trauma, clinical symptoms, and intraocular foreign bodies. Computed tomography scans showed the exact location of the intraocular foreign bodies in the posterior segment in two of the three cases. A B-scan ultrasound was used to determine the location of a non-metallic intraocular foreign body in the third case. All three patients had intraocular foreign bodies, and one of them had an additional orbital foreign body. Case 1 had a perforating eye injury with the additional intraorbital foreign body; Cases 2 and Case 3 had different types of intraocular foreign bodies and prognoses. Various treatment approaches were used, ranging from observation to surgery, depending on the location of the intraocular foreign bodies, and all cases were successfully managed. These three cases show that proper use of various types of imaging tests is indispensable in the context of an intraocular foreign body related to open-globe injury. CONCLUSION: Imaging techniques are crucial for the detection of an intraocular foreign body, and computed tomography is one of the simplest and most useful, especially in cases of open-globe injury.

Microstructural and mechanical analysis of two CAD-CAM lithium disilicate glass-reinforced ceramics

Abstract The aim of this study was to analyze the structural, morphological and mechanical properties of two different lithium disilicate glass-reinforced ceramics for CAD-CAM systems (IPS e.max CAD and Rosetta SM). Five methodologies were used for both ceramics: microstructure (n = 2) was analyzed using x-ray diffraction (XRD); morphological properties (n = 2) were analyzed by scanning electron microscopy (SEM), with and without hydrofluoric etching; porosity (n = 3) was assessed using 3D micro-computed tomography (micro-CT); flexural strength was measured (n =1 0) using the three-point bending test; and bond strength was determined with self-adhesive resin cement (n = 10), using a microshear bond test. After performing all the tests, the data were analyzed using t-Student test and two-way ANOVA. All the tests used a significance level of α = 0.05. High peak positions corresponding to standard lithium metasilicate and lithium disilicate with similar intensities were observed for both ceramics in the XRD analysis. Morphological analysis showed that the crystalline structure of the two ceramics studied showed no statistical difference after acid etching. Additionally, no significant differences were recorded in the number or size of the pores for the ceramics evaluated. Moreover, no differences in flexural strength were found for the ceramic materials tested, or in the bond strength to ceramic substrates for the resin cements. Based on the study results, no significant differences were found between the two CAD-CAM lithium disilicate glass-reinforced ceramics tested, since they presented similar crystalline structures with comparable intensities, and similar total porosity, flexural strength and bond strength.