摘要
ABSTRACT Objective: To evaluate the mechanical properties of mini-implants (MIs) manufactured from stainless steel and compare them with conventional titanium-aluminum-vanadium alloy MIs. Material and Methods: The following groups were formed: G1 (n=24), 8×1.5 mm steel MIs; G2 (n=24), 12×2.0 mm steel MIs; and G3 (n=24), 10×1.5 mm titanium MIs. The 72 MIs were inserted in the infra zygomatic crest region of the maxilla and retromolar trigone in the jaw of 10 pigs. Pull-out, insertion torque, fracture and percussion tests were performed in order to measure the tensile strength, primary stability and fracture strength of MIs. A digital torque gauge was used to measure insertion and fracture torque, a universal mechanical testing machine was used for pull-out testing and a periotest device was used to measure the micromovement of MIs. For morphological and MI component evaluation, scanning electron microscopy (SEM) was performed. D'Agostino & Pearson, Kruskal-Wallis, and Dunn post-hoc and normality tests were used. Results: G2 insertion and fracture torques were significantly higher than G1 and G3 insertion and fracture torques (p<0.05). The pull-out and percussion tests presented similar values among the groups. SEM revealed that the fracture point was predominantly on the fourth thread for steel MIs (G1 and G2) and on the seventh thread for titanium-aluminum-vanadium MIs (G3). Conclusion: The mechanical properties of stainless steel MIs are superior to those of titanium-aluminum-vanadium alloy MIs.
Subject(s)
Animals , Stainless Steel/chemistry , Tensile Strength , Titanium , Orthodontic Anchorage Procedures/instrumentation , Swine , Microscopy, Electron, Scanning/instrumentation , Statistics, Nonparametric , Flexural Strength , Mechanical Tests摘要
ABSTRACT Objective: To assess the efficacy of 5% Glycolic Acid (GA), 17% ethylenediaminetetraacetic acid (EDTA) and 7% maleic acid (MA), in removing the smear layer (SL). Material and Methods: For the experiment, forty single-rooted human teeth were selected. To perform the chemo‑mechanical preparation, the root canals were instrumented to an apical size of #30, along with simultaneous irrigation of 2.5% NaOCl. The samples were allotted to the experimental groups based on the final irrigating solution (n=10): (1) The GA group: 05%, (2) the EDTA group: 17%, (3) the MA group: 7%, and (4) the control group: Distilled water. The teeth were evaluated for the presence or absence of SL using SEM. Results: Comparing the 5% GA, 7% MA and 17% EDTA groups, no statistically significant differences were found at the coronal and middle thirds (p>0.05). However, in the apical third, MA had greater efficacy than EDTA (p=0.002) and GA (p=0.041), with a significant difference in the SL removal, while there was no significant difference between the latter (p=0.148). Conclusion: Thus, it was concluded that 7% maleic acid as a final irrigating solution is more efficacious than 17% EDTA and 5% glycolic acid in eliminating the smear layer from the apical portion of the root canal.
Subject(s)
Humans , Smear Layer , Edetic Acid/chemistry , Root Canal Preparation/instrumentation , Dental Pulp Cavity , Microscopy, Electron, Scanning/instrumentation , Chi-Square Distribution , Statistics, Nonparametric摘要
A engenharia de tecidos ósseos é um ramo importante da medicina regenerativa e envolve o desenvolvimento de arcabouços com composição e arquitetura favoráveis à integração celular, além do estudo de fatores capazes de promover a adesão e proliferação celular, incluindo estímulos químicos e biofísicos. O objetivo do estudo foi avaliar a utilização do laser de baixa intensidade (LBI) como uma ferramenta para promover a bioestimulação in vitro de células osteoblásticas cultivadas em arcabouços nanofibrosos de ácido polilático (PLA). Os arcabouços foram produzidos pela técnica de eletrofiação e caracterizados quanto à molhabilidade, composição pela espectroscopia no infravermelho por transformada de Fourier (FTIR), morfologia da superfície por microscópica eletrônica de varredura (MEV), caracterização termogravimétrica (TGA), calorimetria diferencial exploratória (DSC) e cristalinidade por difração de raios-X (DRX). Os ensaios biológicos foram conduzidos com osteoblastos da linhagem OFCOL II cultivados na superfície dos arcabouços e submetidos ou não (grupo controle) a irradiação com laser diodo InGaAIP na potência de 30 mW, nas doses de 1, 4 e 6 J/cm² e nos comprimentos de onda de 660 nm (grupos V1, V4, V6, respectivo as doses) e 780 nm (grupos I1, I4 e I6, respectivo as doses). Os efeitos do LBI na proliferação dos osteoblastos foram avaliados através do método bioquímico Alamar Blue, nos intervalos de 24, 48 e 72h, enquanto a viabilidade e a morfologia celular foram analisadas no intervalo de 72h, através do ensaio Live/Dead e da microscopia eletrônica de varredura (MEV), respectivamente. Os dados do ensaio bioquímico de Alamar Blue mostraram uma maior proliferação celular nos grupos V6 em todos os intervalos analíticos em comparação ao grupo controle (p<0,05). Outras diferenças entre o grupo controle e irradiados foram encontradas apenas nos intervalos de 48h e 72h para V1, e para o grupo IV6 em 72h. O ensaio Live/Dead revelou um aumento na viabilidade celular nos grupos trados com LBI, sendo significativamente maior no grupo V1 quando comparado ao grupo controle. A análise por MEV mostrou adequada interação dos osteoblastos aos arcabouços, com o corpo celular se espalhando ao longo do eixo da nanofibra e a presença de contatos físicos mais evidentes, através da formação de ligação por meio de filopódios e lamelipódios, nos grupos V1, V6 e I6. Em conjunto, os dados do presente trabalho mostraram que o LBI promove a bioestimulação de osteoblastos cultivados sobre nanofibras de PLA, o que aponta para o seu uso potencial nas técnicas de engenharia tecidual óssea, sobretudo no que se refere ao uso do comprimento de onda de 660 nm, a qual apresentou grupos com mais resultados significativos (AU).
Bone tissue engineering is a relevant branch of regenerative medicine and involves the development of scaffolds with composition and architecture favorable to cell integration, in addition to studying factors capable of promoting cell adhesion and proliferation, including chemical and biophysical stimuli. The study aimed to evaluate the use of low-level laser irradiation (LLLI) to promote in vitro biostimulation of osteoblastic cells cultured on polylactic acid (PLA) nanofibrous scaffolds. The scaffolds were produced by the electrospinning technique and characterized in terms of wettability, composition by Fourier transform infrared spectroscopy (FTIR), surface morphology by scanning electron microscopy (SEM), thermogravimetric characterization (TGA), differential scanning calorimetry (DSC) and crystallinity by Xray diffraction (XRD). The biological assays were conducted with osteoblasts of the OFCOL II lineage cultured on the surface of the scaffolds and submitted or not (control group) to irradiation with InGaAIP diode laser, power of 30 mW, with doses of 1, 4 and 6 J/cm² and wavelengths of 660 nm (groups V1, V4, V6, respectively doses) and 780 nm (groups I1, I4 and I6, respectively doses). The effects of LLLT from the perspective of osteoblasts were evaluated using the biochemical method Alamar Blue assay, at intervals of 24, 48 and 72h, while cell viability and morphology were observed at 72h, using the Live/Dead assay and electron microscopy. scan (SEM), respectively. The Alamar Blue assay data showed more significant cell proliferation in groups in the V6 groups at all analytical intervals compared to the control group (p<0.05). Other differences between the control and irradiated groups were found only at intervals of 48h and 72h for V1, and for group IV6 at 72h. The Live/Dead assay revealed an increase in cell viability in the groups treated with LLLT, being significantly higher in the V1 group when compared to the control group. SEM analysis showed adequate interaction between osteoblasts and scaffolds, with the cell body spreading along the nanofiber axis and the presence of more evident physical contacts, through the formation of bonds through filopodia and lamellipodia, in groups V1, V6 and I6. Together, the data from the present study observed that LLLT promotes the biostimulation of osteoblasts cultured on PLA nanofibers, which pointed to its potential use in bone tissue engineering techniques, especially with regard to the use of the wavelength of 660 nm, which presented groups with more significant results (AU).
Subject(s)
Osteoblasts , Bone Regeneration , Low-Level Light Therapy/instrumentation , Tissue Engineering , In Vitro Techniques/methods , Calorimetry, Differential Scanning/instrumentation , Microscopy, Electron, Scanning/instrumentation , Spectroscopy, Fourier Transform Infrared/instrumentation摘要
Abstract Objective: To evaluate the efficacy of desensitizing agents for the obliteration of dentinal tubules subjected or not to a simulated oral environment. Material and Methods: Dentinal discs (n=8) treated with Riva-Star (RS) or PRG-Barrier-Coat (PRG) were submitted (cycled) or not submitted (control) to erosive-abrasive-thermal cycles and evaluated using scanning electron microscopy/energy dispersive spectroscopic analysis. The variables analyzed were tubule obliteration and dentin surface chemical composition. Data were analyzed by non-parametric tests (p<0.05). Results: The cycled and control groups did not differ significantly for the responses in each material. The PRG control and cycled groups had fewer visible tubules and a higher proportion of totally obliterated tubules than the RS groups. The percentages of silver coverage were higher in the RS-control than in the RS-cycled. There was a significant inverse correlation between the presence of silver and non-obliterated tubules (R=-0.791; p<0.001). The percentages of carbon, aluminum, strontium, and potassium were significantly higher in the PRG-control and PRG-cycled compared to the RS control. The percentages of calcium, phosphorus, and silver were significantly higher in the RS compared to the PRG groups. PRG-control showed a higher percentage of boron than RS-control. Conclusion: PRG promoted greater tubule obliteration than SR. Simulated stress did not affect the obliterating effect of each agent. Greater silver coverage corresponded to a lower proportion of non-obliterated tubules in RS. Carbon, aluminum, strontium, boron, and potassium predominated in the dentin surface treated with PRG, while calcium, phosphorus, and silver prevailed in RS groups (AU).
Subject(s)
Potassium Iodide , Microscopy, Electron, Scanning/instrumentation , Dentin Sensitivity/drug therapy , Dentin Desensitizing Agents/therapeutic use , In Vitro Techniques , Statistics, Nonparametric摘要
Abstract Objective: To evaluate the effect of two types of light-curing units (second and third generations) and two types of bulk-fill composite resins with different photoinitiators - Tetric N-Ceram Bulk Fill (TNCB) and Xtra Fil (XTF) on gap formation at the gingival margins of Cl II restorations. Material and Methods: Fifty-six standard Cl II cavities were prepared on the mesial and distal surfaces of premolar teeth, with the gingival margin of the cavities 1 mm apical to the CEJ. The samples were randomly assigned to two groups based on the composite resin type and two subgroups based on the light-curing unit type and restored. After 5000 rounds of thermocycling, gingival margin gap in each sample was measured in µm under an electron microscope at ×2000 magnification. Data were analyzed by two-way ANOVA and Tukey tests (α=0.05). Results: Marginal gaps of TNCB composite resin were significantly smaller than those of XTF composite resin (p<0.001). There were no significant differences between the two light-curing units in each group (p=0.887 with XTF and p=0.999 with TNCB). Conclusion: The gaps at gingival margins of Cl II cavities with TNCB bulk-fill composite were smaller than XTF composite resin. Both composite resins can be cured with both the second- and third-generation LEDs (AU).
Subject(s)
Humans , Bicuspid , Dental Marginal Adaptation , Composite Resins/chemistry , Light-Curing of Dental Adhesives/instrumentation , Photoinitiators, Dental/chemistry , In Vitro Techniques/methods , Microscopy, Electron, Scanning/instrumentation , Analysis of Variance摘要
Introdução: Os fios Copper Ni-Ti (CuNiTi) possuem indicações de uso clínico específicas, permanecendo no ambiente bucal por um longo período. Por esse motivo suas características mecânicas, termodinâmicas e estruturais devem ser preservadas durante todo o período de uso. Objetivos: Investigar se ocorrem alterações no comportamento mecânico, termodinâmico, estrutura e composição química superficial em fios CuNiTi 35°C submetidos ao envelhecimento in vivo (uso clínico) e in vitro (termociclagem), evidenciando as possíveis diferenças entre os métodos de envelhecimento. Material e Métodos: A amostra total foi constituída de 30 arcos pré-contornados 0.016", termodinâmicos com adição de cobre, e temperatura austenítica final (Af) de 35°C, da marca Ormco®. As análises destes fios resultaram em dois capítulos. Para o experimento clínico, 10 unidades de fios foram instaladas em 05 pacientes e permaneceram em meio bucal durante 30, 60 e 90 dias, e 05 fios foram analisados como recebidos (CR). A cada período, um hemiarco completo mais 1/3 (um terço) do hemiarco inferior direito foi retirado para análises. Para o experimento in vitro os 15 fios restantes foram submetidos à termociclagem para simulação do envelhecimento em ambiente oral durante 30 (600 ciclos), 60 (1200 ciclos) e 90 dias (1800 ciclos) com variação de temperatura entre 5°C e 55°C, com banhos de 90 segundos em cada temperatura, e transição de 15 segundos entre os banhos. Após cada período de envelhecimento in vivo e in vitro, os fios foram submetidos a um teste de padronização das suas dimensões através da medição dos diâmetros com paquímetro, Microscopia Eletrônica de Varredura (MEV), Espectrometria por Raios X Fluorescentes (FRX), ensaios de tração uniaxial e ensaio de Varredura Diferencial de Calorimetria (DSC). Resultados: No capítulo 1 a comparação entre os fios CR e os envelhecidos revelou que não houve diferença significativa entre os diâmetros das amostras, das forças obtidas ou mesmo das temperaturas Af, independentemente do tempo de permanência em boca. Foram encontrados predominantemente Ni, Ti, Cu e Al nas amostras, além de outros elementos químicos em concentrações variadas. No capítulo 2 não houve diferença significativa entre os diâmetros das amostras, das forças obtidas ou mesmo das temperaturas Af entre as amostras, independentemente do tempo ou do método de envelhecimento. Conclusão: As análises laboratoriais dos fios envelhecidos in vivo e in vitro foram comparadas, evidenciando que as características mecânicas, termodinâmicas e químicas dos fios permanecem estáveis mesmo até 90 dias de uso clínico ou 1800 ciclos de termociclagem. O método de envelhecimento in vitro se mostra uma alternativa viável para a análise destes parâmetros, em substituição aos métodos in vivo (AU).
Introduction: Copper Ni-Ti wires (CuNiTi) have specific indications for clinical use, remaining in the oral environment for a long period. For this reason, their mechanical, thermodynamic and structural characteristics must be preserved throughout the period of use of these materials. Objectives: To investigate whether there are changes in the mechanical, thermodynamic, structure and surface chemical composition of CuNiTi 35°C wires subjected to in vivo aging (clinical use) and in vitro (thermocycling), highlighting the possible differences between the aging methods. Material and Methods: The total sample was obtained from 30 pre-contoured Ormco® 0.016 thermodynamic archwires with copper addition and austenitic final temperature (Af) of 35°C. The analysis of these archwires resulted in two articles. For the clinical experiment, 10 units of wires were installed in 05 patients and remained in the oral environment for 30, 60 and 90 days, and 05 wires were analyzed as received. At each period, a complete hemiarch plus 1/3 of the right lower hemiarch was removed for analysis. For the in vitro experiment, the 15 remaining wires underwent thermocycling to simulate the aging of the oral environment for 30 (600 cycles), 60 (1200 cycles) and 90 days (1800 cycles) with a temperature range between 5°C and 55°C, with 90 second baths at each temperature, and 15 second transition between baths. After each in vivo and in vitro aging period, the wires underwent to a standardization test of their dimensions, by defining the diameters with a caliper, Scanning Electron Microscopy (SEM), Fluorescent X-Ray Spectrometry (FRX), tests of Uniaxial traction and Differential Scanning Calorimetry (DSC) test. Results: In chapter 1, the comparison between CR and aged wires revealed that there was no significant difference between the sample diameters, the forces obtained or even the temperatures Af, regardless the time spent in the mouth. Predominantly Ni, Ti, Cu and Al were found in the samples, in addition to other chemical elements in different concentrations. In chapter 2 there was no significant difference between the diameters of the samples, the forces obtained or even the temperatures Af between the samples, regardless of time or aging method. Conclusion: The comparison of the laboratoral analyzes of the archwires aged in vivo and in vitro showed that the mechanical, thermodynamic and the surface chemical characteristics were stable, even up to 90 days of clinical use or 1800 thermocycling cycles. The in vitro aging method is a viable alternative for the analysis of these parameters, replacing the in vivo methods (AU).
Subject(s)
Orthodontic Wires , Orthodontics , Spectrometry, X-Ray Emission/instrumentation , Smart Materials , Calorimetry, Differential Scanning , Microscopy, Electron, Scanning/instrumentation摘要
Introdução:As atuaisresinas Bulk-Fill apresentamcomovantagens e propriedades: menor tempo clínico, baixa contração de polimerização, maior translucidez, entre outros. Objetivo:Avaliar a topografia superficial de restaurações com diferentes tipos de resina composta antes e após submetê-las a diferentes sistemas de acabamento e polimento. Metodologia:Confecção de100 corpos de prova, sendo 50 de cada composto resinoso, apresentando cinco grupos (n=10) sorteados de forma aleatória, de acordo com o sistema de acabamento e polimento empregado. Foram utilizadas as resinas Filtek Z350 XT e a Bulk Fill Filtek One Bulk Fill e os sistemas de acabamento e polimento: Discos de Lixa Sof-Lex Pop On Kit;Discos Diamantado Espiral Sof-Lex; Ponta Enhance e Broca Carbide Multilaminada nº 0283F, que foram comparados com superfície deixada pela Tira de Poliester (Controle Negativo). Após 7 dias de armazenamento em água destilada, os corpos de provaforam submetidos aoMicroscópio Eletrônico de Varredura.Resultados:Os corpos de provada resina Bulk Fill tiveram como melhor resultado o sistema de acabamento e polimentocom broca carbidee resultado não satisfatório com discodiamantado espiral Sof-lex, enquanto a ponta Enhance e lixa Sof-lex Pop Ontiveram resultados semelhantes. Os corpos de prova da resina Filtek Z350 XT tiveram melhor aspecto visual de lisura no grupo controle negativoe pior resultado no grupo com disco diamantado espiral Sof-lex. Conclusões:Dessa forma, o sistema que apresentou melhor resultado foi a broca Carbidena resina Bulk Fill, enquanto a Filtek Z350 XT apresentou-se melhor no grupo controle. Porém, ainda são necessáriosestudos para se chegar em um protocolo de acabamento e polimento mais eficiente (AU).
Introduction:The current Bulk-Fill resins have the following advantages and properties: less clinical time, low polymerization shrinkage, greater translucency, among others.Objective:Toevaluate the topography of restorations with different types of composite resin before and after submitting them to different finishing and polishing systems.Methodology:Manufacture of 100 specimens, 50 of each resin compound, presenting five groups (n = 10) drawn at random, according to the finishing and polishing system employed. Filtek Z350 XT resins and Bulk Fill Filtek One Bulk Fill andfinishing and polishing systems were used: Sof-Lex Pop On Kit Sanding Discs; Diamond Spiral Sof-Lex Discs; Tip Enhance and Multilaminated Carbide Drill nº 0283F, which were compared with the surface left by the Polyester Strip (Negative Control). After 7 days of storage in distilled water, the specimens were submitted to a Scanning Electron Microscope.Results:The Bulk Fill resin specimens had the best result of the finishing and polishing system with carbide drill and unsatisfactory result with Sof-lex spiral diamond disc, while the Enhance tip and Sof-lex Pop On sandpaper had similar results. The Filtek Z350 XT resin specimens had a better visual aspect of smoothness in the negative control group and a worse result in the group with Sof-lex spiral diamond wheel.Conclusions:Thus, the system that showed the best result was the Carbide drill in Bulk Fill resin, while Filtek Z350 XT was better in the control group. However, studies are still needed to arrive at a more efficient finishing and polishing protocol (AU).
Introducción:Las actuales resinas Bulk-Fill tienen las siguientes ventajas y propiedades: menor tiempo clínico, baja contracción de polimerización, mayor translucidez, entre otras.Objetivo: Evaluar la topografía de restauraciones con diferentes tipos de resina compuesta antes y después de someterlas a diferentes sistemas de acabado y pulido.Metodología: Fabricación de 100 probetas, 50 de cada resina compuesta, presentando cinco grupos (n = 10) extraídos al azar, según el sistema de acabado y pulido empleado. Se utilizaron resinas Filtek Z350 XT y Bulk Fill Filtek One Bulk Fill y sistemas de acabado y pulido: Discos de lijado Sof-Lex Pop On Kit; Discos Sof-Lex en espiral de diamante; Broca Realce de Punta y Carburo Multilaminado nº 0283F, que fueron comparadas con la superficie dejada por la Tira de Poliéster (Control Negativo). Después de 7 días de almacenamiento en agua destilada, lasmuestras se sometieron a un Las muestras de resina Bulk Fill tuvieron el mejor resultado del sistema de acabado y pulido con broca de carburo y un resultado insatisfactorio con el disco de diamante en espiral Sof-lex, mientras que la punta Enhance y el papel de lija Sof-lex Pop On tuvieron resultados similares. Las muestras de resina Filtek Z350 XT tuvieron un mejor aspecto visual de suavidad en el grupo de control negativo y un peor resultado en el grupo con disco de diamante en espiral Sof-lex.Conclusiones: Así, el sistema que mejor resultado mostró fue la broca Carbide en resina Bulk Fill, mientras que Filtek Z350 XT fue mejor en el grupo control. Sin embargo, aún se necesitan estudios para llegar a un protocolo de acabado y pulido más eficiente (AU).
Subject(s)
Surface Properties , Microscopy, Electron, Scanning/instrumentation , Composite Resins , Dental Polishing/instrumentation , In Vitro Techniques/methods , Brazil , Polymerization摘要
ABSTRACT Objective: To determine in vitro the frequency, shape, type, diameter, and patency of accessory canals in the primary molars pulp chamber floor. Material and Methods: Sixteen healthy primary molars were evaluated by micro-computed tomography and scanning electron microscopy. Descriptive analyses of the frequency, shape (round, oval, or irregular), type (blind, true, or hidden), patency and diameter of the accessory canals were performed. Results: Half of the teeth presented accessory canals, 62.5% of which were located in the upper molars and 37.5% in the lower molars. The most frequent shape was irregular. In three-dimensional analysis, blind accessory canals (12.5%) and with patency (18.7%) of the teeth were observed. The average accessory canal diameter was 51.97 µm (± 26.03 µm). Conclusion: Upper molars showed a higher frequency of accessory canals with larger diameters. The irregular shape was the most frequent. 18.7% of accessory channels showed patency.
Subject(s)
Humans , Male , Female , Child , In Vitro Techniques/methods , Microscopy, Electron, Scanning/instrumentation , Root Canal Preparation/instrumentation , X-Ray Microtomography/instrumentation , Molar , Brazil/epidemiology , Statistics, Nonparametric , Dental Pulp Cavity/anatomy & histology摘要
Abstract The present study focused on the use of pineapple plant stem, which is an agro-waste, for the production of starch (11.08 % ± 0.77). Characters were studied using X-ray diffraction, nuclear magnetic resonance spectroscopy (NMR), fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and rheological methods. The granular size of stem starch was comparatively smaller than corn starch granules. The X-ray diffraction data revealed that stem starch has an A-type crystal structure. The molecular structure was similar to those obtained for native starches, which is confirmed by NMR and FTIR. The gelatinization temperature was observed to be higher than corn starch and rheological studies revealed; stem starch is more viscous than corn starch. The purity analysis showed that the harmful heavy metals were in negligible quantity and the tested pesticides were absent. This could make this a good source of starch for food industries. Results revealed that this agro-waste has a high potential for the production of good quality starch.
Subject(s)
Ananas , Agribusiness , Resistant Starch , Calorimetry, Differential Scanning/instrumentation , Microscopy, Electron, Scanning/instrumentation , Magnetic Resonance Spectroscopy/instrumentation , Spectroscopy, Fourier Transform Infrared/instrumentation摘要
Abstract Objective: To evaluate the topography and microhardness of composite resin restorations submitted to different finishing and polishing systems before and after erosive challenge. Material and Methods: Thirty standardized cavities prepared in enamel-dentin blocks of bovine incisors were restored with Z350 composite resin, and randomly distributed into three groups (n=10) according to the finishing and polishing systems: G1 = Soflex 4 steps, G2 = Soflex Spiral 2 steps and G3 = PoGo (single step). The specimens were half protected with nail varnish and submitted to five immersions in Pepsi Twist®, for 10 minutes each, five times/day during six consecutive days. The initial and final challenge surface microhardness (SMHinitial and SMHfinal) of the composite resin was evaluated and the percentage of SMH loss (%SMHL) was calculated. After protection removal, the topographic change linear (Ra) and volumetric (Sa) roughness was evaluated in initial and final areas by using 3D non-contact optical profilometry and scanning electron microscopy (SEM). Data were analyzed by paired Student's t-test, Kruskal-Wallis test, and by ANOVA and Tukey's test. Results: There was significant intra-group %SMHL in composite resin (p<0.05). Differences among groups in %SMHL, Ra/Sa in resin composite were not observed (p>0.05). SEM images revealed structural changes between the initial and final surfaces for all groups. Conclusion: The three types of finishing and polishing systems had a similar influence on %SMHL, Ra and Sa in the nanofilled composite resin.
Subject(s)
Animals , Cattle , Tooth Erosion/etiology , Composite Resins , Dental Enamel , Dentin , Incisor , Microscopy, Electron, Scanning/instrumentation , Analysis of Variance , Statistics, Nonparametric , Immersion摘要
Abstract Objective: To evaluate the effect of a calcium nanocompound on the reduction of erosive tooth wear and abrasion. Material and Methods: Bovine enamel specimens (BE), were randomly assigned to the following groups (n = 10): G1 = Calcium mesoporous silica nanoparticles (Ca2+MSNs); G2 = casein phosphopeptide-amorphous calcium phosphate (CPP-ACP, 2% CPP-ACP, GC®); G3 = casein phosphopeptide-amorphous calcium fluoride phosphate (CPP-ACFP, 2% CPP-ACP + 900 ppm F-, GC®); G4 = sodium fluoride NaF (900 ppm F-, positive control); and G5 = distilled and deionized water (negative control). Each product was applied to the exposed area for one minute, three times per day for three consecutive days, and followed by the immersion of the specimens in Sprite Zero™ - a low-pH solution (2.58) for five minutes (Coca-Cola™). After the first and last erosive challenges of the day, the specimens were submitted to abrasion in a toothbrush machine for 15 seconds (200 g/BE). The specimens were analysed using 3D non-contact optical profilometry, with tooth structure loss (TSL) measurements and scanning electron microscopy (SEM). TSL values were analysed by Kruskal-Wallis and Mann-Whitney tests (p<0.05). Results: There were no significant differences between G1 (10.95 µm) and G3 (10.80 µm) treatments for TSL values; however both resulted in significantly reduced TSL values compared with the G5 (16.00 µm) (p<0.05). The G4 (12.26 µm) showed no statistically significant difference when compared to the G5 (16.00 µm). The groups G1 and G3 presented higher surface preservation than the G5. Conclusion: Ca2+MSNs was effective for reducing tooth surface loss caused by erosive tooth wear and abrasion.
Subject(s)
Animals , Cattle , Sodium Fluoride/therapeutic use , Tooth Abrasion/pathology , Tooth Erosion/diagnosis , Calcium Fluoride/therapeutic use , Tooth Wear/etiology , Brazil/epidemiology , Microscopy, Electron, Scanning/instrumentation , Statistics, Nonparametric , Dental Enamel , Nanoparticles , Clinical Trial Protocol , Hydrogen-Ion Concentration摘要
Abstract Objective: To assess the antibacterial and smear layer removal ability of Trigonella foenum, Syzygium cumini, Terminalia chebula seed extracts against E. faecalis dentinal biofilm. Material and Methods: Agar well diffusion, micro broth dilution assay and time-kill curve assay were performed to determine the antibacterial activity. The ability of the herbal extracts to remove the smear layer on the root canal surface was assessed by scanning electron microscopy. Results: Antibacterial activity was observed for the extracts of S. cumini and T. chebula on E. faecalis dentinal biofilm and its planktonic counterparts. The smear layer was efficiently removed by the seed extracts of T. chebula alone. Seed extracts of T. foenum neither possessed antibacterial effect nor smear layer removal ability. Conclusion: The extracts of T. chebula seeds may replace conventional irrigant due to its antibacterial properties and smear layer removing the ability. The extracts of S. cumini may be used as an intracanal medicament as it exhibited a bactericidal effect against the E. faecalis dentinal biofilm following 18 hours of incubation.
Subject(s)
Microscopy, Electron, Scanning/instrumentation , Root Canal Preparation/instrumentation , Syzygium/microbiology , Plant Preparations/therapeutic use , Endodontics , Statistics, Nonparametric , Biofilms , Agar , India/epidemiology , Anti-Bacterial Agents摘要
Psychotria fractistipula L.B.Sm, R.M. Klein & Delprete (Rubiaceae) is found in the existing Atlantic Forest in the South of Brazil, in the Paraná and Santa Catarina States. The members of Rubiaceae are characterized chemically by the presence of alkaloids, some pharmacological properties of which include antifungal, antibacterial, analgesic, antioxidant, antimutagenic, and antiviral activities. In this study, we report the results of anatomical, morphological, and histochemical analyses of the leaves and stems of the Rubiaceae family member, P. fractistipula. The anatomical analysis involved of light microscopy and scanning electron microscopy. Morpho-anatomical and histochemical characterization were made using standard methodology. The isolated compounds were identified by Nuclear Magnetic Resonance spectroscopic analysis. The following structures are highlighted as the distinctive features of the species: presence of petiolate leaves and a petiole base, leaf blade with smooth cuticle on both surfaces, paracytic stomata, and, dorsiventral mesophyll and presence of trichomes on the leaves and stems. Phytosteroids, identified as β-sitosterol and campesterol, were observed in the hexane fraction of the stem. Future studies should focus on the isolation of other fractions of interest and their characterization through specific biological and cytotoxicity assays.
Subject(s)
Rubiaceae/classification , Psychotria/classification , Phytochemicals/adverse effects , Microscopy, Electron, Scanning/instrumentation , Magnetic Resonance Spectroscopy/methods , Microscopy, Electron, Scanning Transmission/methods , Research Report , Trichomes/anatomy & histology , Analgesics/pharmacology , Antioxidants/pharmacology摘要
Objective: To determine and compare the remineralizing capacity of self-assembling peptide (SAP) P11-4 and casein phosphopeptidesamorphous calcium phosphate (CPP-ACP) on enamel. Material and Methods: Enamel samples were divided into 2 groups. Group I was treated with Selfassembling peptide (SAP) P11-4 and group II with casein phosphopeptides-amorphous calcium phosphate (CPP-ACP). In both groups, remineralizing capacity was assessed at baseline, 2 weeks, 6 weeks and 12 weeks. Student's t- test and ANOVA were applied, with the significance level set at 5%. Results: The mean calcium weight % was evaluated at baseline, 2 weeks, 6 weeks and 12 weeks. In Group I, there was increase in mean value (62.12 ± 1.24) from baseline to 12 weeks (67.36 ± 2.14). However, there was decrease in phosphate weight % from 37.16 ± 2.52 at baseline to 35.72 ± 2.11 at 12 weeks. In Group II, mean calcium weight % was 64.18 ± 1.52 at baseline, which ultimately increased to 66.01 ± 2.03 at 12 weeks. Phosphate weight % showed reduction from 37.34 ± 2.23 at baseline to 35.04 ± 2.02 at 12 weeks. Ca/P ratio showed significant improvement. There was significant difference in Ca/P ratio at 2 weeks, 6 weeks and 12 weeks in both groups (p<0.05). Conclusion: Self-assembling peptide (SAP) P11-4 found to be more effective and efficient as compared to casein phosphopeptidesamorphous calcium phosphate (CPP-ACP).
Subject(s)
Humans , Adolescent , Adult , Phosphopeptides , Tooth Remineralization/methods , In Vitro Techniques/methods , Caseins , Dental Enamel , Bicuspid , Calcium Phosphates , Microscopy, Electron, Scanning/instrumentation , Analysis of Variance , India摘要
Objective: To evaluate and compare the remineralization potential of a dentifrice containing bioactive glass and a topical cream containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) in remineralizing artificial carious lesion on enamel. Material and Methods: Forty-five freshly extracted human permanent premolar teeth were selected. Samples were divided into three groups: GI - regular tooth paste without specific remineralizing agent; GII - tooth paste containing calcium sodium-phosphosilicate (novamin) and GIII - topical cream containing casein phosphopeptide-amorphous calcium phosphate. All the sound enamel samples were viewed under scanning electron microscope (SEM) to assess the topographical pictures of enamel surface and energy dispersing x-ray analysis (EDAX) was done to estimate quantitatively the amounts of mineral (calcium and phosphorous). The mineral content of calcium and phosphorus after demineralization in each group was noted. The samples were then subjected to SEM and EDAX. Results: GI does not show any increase in the calcium and phosphorus after applying toothpaste without any remineralizing agent but GII and GIII showed a net increase in calcium and phosphorous values after applying concern-remineralizing agents. Inter group comparison showed GIII yield higher net calcium and phosphorous values than GII. Conclusion: Two remineralizing agents showed remineralization potential on enamel surfaces. Casein phosphopeptide-amorphous calcium phosphate showed better remineralizing potential than calcium sodium phosphosilicate. Hence CPP-ACP can be considered as the material of choice in remineralizing early enamel carious lesions.
Subject(s)
Humans , Tooth Remineralization , Bicuspid , In Vitro Techniques/methods , Calcium Phosphates , Caseins , Microscopy, Electron, Scanning/instrumentation , Radiography, Dental/instrumentation , Analysis of Variance , Statistics, Nonparametric , India摘要
Abstract Salacia oblonga Wall belonging to family Celastraceae contains vital phytoconstituents and has been used since long for the treatment of diabetes, inflammation and burn wounds. S. oblonga ethyl acetate root extract was evaluated for antibacterial activity towards drug resistant pathogens Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumoniae. Further 260 nm absorbing material was estimated in the control and treated cells. Interestingly 260 nm absorbance material is higher in the Staphylococcus aureus. Further the effect of the plant extract on drug resistant pathogen S. aureus was examined by scanning electron microscopy (SEM). SEM results have shown that treated bacterial cells have changed in morphology, size and reduced in number. Based on these results it can be concluded that S. oblonga extract acts on membrane of the drug resistant pathogen S. aureus.
Subject(s)
Salacia/drug effects , Anti-Bacterial Agents/adverse effects , Noxae/adverse effects , Microscopy, Electron, Scanning/instrumentation摘要
Abstract The purpose of the study was to develop a xenogenic bubaline diaphragm matrix (BDM) for abdominal hernia repair. A fresh diaphragm was decellularized using aqueous sodium dodecyl sulfate (SDS) solutions (0.5-4% w/v) over a period. Acellularity was confirmed histologically and characterized by Masson's trichrome staining, scanning electron microscopy (SEM), DNA quantification, agarose gel electrophoresis, and Fourier-transform infrared spectroscopy. The BDM was used for clinical abdominal hernia repair in six cattle. Clinical, hemato-biochemical and antioxidant parameters were evaluated to assess biocompatibility of xenogenic BDM. Histologically, the diaphragm treated with 2% SDS for 48 h showed complete acellularity and orderly arranged collagen fibers. The SEM confirmed preservation of collagen structure and integrity. The DNA content was significantly (P < 0.05) reduced in BDM (33.12 ± 5.40 ng/mg) as compared to the native diaphragm (443.96 ± 162.60 ng/mg). DNA extracts from BDM show considerable removal of DNA material, with absence of DNA band in agarose gel. The FTIR spectrum of BDM has shown all characteristic transmittance peaks of bovine skin collagen indicating preserved collagen structure. Six cattle with BDM implant recovered uneventfully and remained sound at least upto 6 months. Hemato-biochemical and antioxidant findings were unremarkable. Bubaline diaphragm matrix shows excellent repair efficiency and biocompatibility for abdominal hernia repair in cattle without complications.
Subject(s)
Buffaloes , Diaphragm/abnormalities , Hernia, Abdominal/physiopathology , Spectrum Analysis/instrumentation , Materials Testing/methods , Microscopy, Electron, Scanning/instrumentation摘要
Zeólitas e carvão ativado são materiais eficazes para o tratamento de efluentes devido a sua grande área superficial e possibilidades de funcionalização, que permitem o desenvolvimento de novos materiais derivados visando a processos de concentração/remoção de contaminantes, por exemplo, em águas. A preparação de nanocompósitos magnéticos e sua aplicação na remoção seletiva de poluentes em meio aquoso tornou-se viável devido as interações distintas que ocorrem entre zeólita e carvão ativado com compostos orgânicos, íons metálicos e compostos nitrogenados. Assim, novos materiais voltados para sistemas de tratamento de águas residuais e monitoramento ambiental foram desenvolvidos com base em materiais bem estabelecidos. Os nanocompósitos foram caracterizados estrutural e morfologicamente por técnicas de microscopia eletrônica de varredura, termogravimetria, espectroscopia no infravermelho, espalhamento de luz, difração de raios x, bem como suas capacidades de adsorção. Foi avaliado também a viabilidade de aplicações em métodos analíticos, como pré-concentração por extração em fase sólida magnética (M-SPE), e, para tratamento de efluentes em amostras reais. Contaminação por cromo (VI), outras espécies potencialmente tóxicas e amônio foram removidos de águas residuais, gerando produtos tratados com níveis de contaminantes suficientemente baixos para atenderem as recomendações da EPA (Environmental Protection Agency) e CONAMA (Conselho Nacional do Meio Ambiente), permitindo seu descarte na natureza. Os materiais demonstraram ser adequados para pré-concentração rápida, eficiente, economicamente competitiva e ambientalmente amigável de amostras por M-SPE para quantificação analítica de espécies orgânicas ou inorgânicas, por técnicas analíticas convencionais. Assim, foi demonstrado a possibilidade de determinação simultânea de elementos potencialmente tóxicos e de outros cátions metálicos em concentrações traço (ppb), diretamente no material compósito magnético, por espectroscopia de fluorescência de raios X de energia dispersiva (EDX), além da quantificação de traços de compostos orgânicos semi-voláteis por cromatografia emfase gasosa com detector por espectrometria de massas, aumentando a sensibilidade para além do limite nominal de detecção por essas técnicas
Zeolites and activated carbon are effective materials for the treatment of effluents due to their large surface area and functionalisation possibilities, which allow the development of new derived materials aiming at the concentration/removal of contaminants from water, for example. The preparation of magnetic nanocomposites and their application in the selective removal of pollutants in aqueous media has become feasible due to the distinct interactions that occur between zeolite and activated carbon with organic compounds, metal ions and nitrogen compounds. Thus, new materials for wastewater treatment and environmental monitoring systems were developed based on well-established materials. The nanocomposites were structural and morphologically characterized by scanning electron microscopy, thermogravimetry, infrared spectroscopy, light scattering, x-ray diffraction, as well as their adsorption capacities, viability of applications in analytical methods such as preconcentration by extraction in magnetic solid phase, M-SPE, were evaluated, and the composite materials Cmag and Zmag applied for treatment of real samples. Chromium (VI) contamination, heavy metal cations and ammonium were removed from wastewater, generating treated products with levels of contaminants low enough to meet the EPA and CONAMA recommendations, allowing their disposal in the wild. The materials have been shown to be suitable for rapid, efficient, economically competitive and environmentally friendly preconcentration of samples per M-SPE for analytical quantification of organic or inorganic species by conventional analytical techniques. Thus, it was demonstrated the possibility of simultaneous analysis of heavy metals and other metal cations in trace concentrations (ppb), directly in the magnetic composite material, by dispersive energy X-ray fluorescence spectroscopy (EDX), in addition to the quantification of traces of volatile organic compounds (VOC) by gas chromatography with mass spectrometry detector, increasing the sensitivity beyond the nominal limit of detection by these techniques
Subject(s)
Industrial Effluent Treatment/analysis , Environmental Pollutants/adverse effects , Solid Phase Extraction , Thermogravimetry/instrumentation , Microscopy, Electron, Scanning/instrumentation , Charcoal/analysis , Zeolites/analysis摘要
O objetivo deste trabalho foi avaliar a rugosidade superficial, a molhabilidade, a disposição em profundidade das partículas de carga, o mapeamento de elementos químicos, a microtopografia em 3D e a micromorfologia de compósitos convencionais e bulk fill após polimento adicional. Éspécimes foram preparados de cada compósito testado, sendo quatro do tipo bulk fill (Filtek Bulk, Fill Tetric N-Ceram Bulk Fill, Opus Bulk Fill e X-tra Fil) e quatro convencionais (Filtek Z250 XT, Grandioso, Tetric NCeram, Vittra APS), de acordo com três técnicas de acabamento/polimento/polimento adicional (n = 10): sem acabamento e polimento, acabamento e polimento com borrachas abrasivas (Astropol), acabamento e polimento com Astropol mais polimento adicional com escova de carbeto de silício. A rugosidade superficial (Ra) e o ângulo de contato foram medidos usando-se um perfilômetro e goniômetro adaptado, respectivamente. A microtopografia 3D foi avaliada utilizando microscopia de força atômica (MFA), enquanto a micromorfologia e a disposição em profundidade das partículas de carga, através da microscopia eletrônica de varredura (MEV). O mapeamento de elementos químicos foi avaliado por meio de Espectroscopia por energia dispersiva de raio-X (EDS). A rugosidade e o ângulo de contato foram analisados pelo ANOVA-dois fatores e teste de Tukey (p <0,05); os demais dados foram analisados descritivamente. A disposição das partículas de carga em profundidade de todas as resinas envolvidas neste estudo apresentou uma camada superficial rica em matriz orgânica e uma camada subsuperficial rica em partículas de dimensões mais diminutas. O polimento adicional: diminuiu a rugosidade superficial das resinas Filtek Bulk Fill, Vittra APS, Tetric N-ceram Bulk Fill e X-tra fil; aumentou o valor do ângulo de contato da X-tra Fil e diminuiu da Filtek Z250 XT. Nas análises para microtopografia em 3D e a micromorfologia, superfícies mais lisas e uniformes foram observadas em todas as resinas. Os elementos: carbono (C), cxigênio (O), silício (Si), zircônia (Zr) e alumínio (Al) foram presentes em todas as resinas compostas. O bário (Ba) foi ausente na Filtek Z250 XT, Filtek Bulk Fil e Vittra APS. O carbono foi predominante em todas as resinas. Após polimento adicional, houve um aumento na detecção de oxigênio para todas as resinas, exceto para Tetric N-Ceram e Xtra Fil e uma diminuição de carbono, exceto para a Tetric N-Ceram Bulk Fil. O silício diminuiu apenas nas resinas Z250 XT, Tetric N-Ceram e Tetric N-Ceram Bulk Fill. A zircônia diminuiu para a Tetric N-Ceram Bulk Fill e o alumínio para Z250 XT e Tetric N-Ceram Bulk Fill. O bário aumentou para Opus Bulk fill e X-tra Fil. O titânio foi ausente para todas as resinas. Portanto, o polimento adicional melhorou as propriedades de superfície das resinas estudadas (AU).
The objective of this study was to evaluate the surface roughness, wettability, the depth distribution of the charge particles, the mapping of chemical elements, the 3D microtopography and the micromorphology of the composites of the conventional and bulk fill after additional polishing. The specimens were prepared from each of the composites tested, four of them being bulk fillers (Filtek Bulk Fill Tetric N-Ceram Bulk Fill Opus Bulk Fill X-tra Fil) and four conventional ones (Filtek Z250 XT, Grandioso, Tetric N-Ceram, Vittra APS ), according to three additional finishing / polishing / polishing techniques (n = 10): without finishing and polishing, finishing and polishing with abrasive rubbers (Astropol), finishing and polishing with Astropol plus additional polishing with silicon carbide brush. The surface roughness (Ra) and contact angles were measured using a profilometer and adapted goniometer, respectively. The 3D microtopography was evaluated using atomic force microscopy (AFM); while the micromorphology and the in-depth arrangement of the charge particles by scanning electron microscopy (SEM). The mapping of chemical elements was evaluated by means of X-ray Dispersive Energy Spectroscopy (EDS). The roughness and the contact angle were analyzed by ANOVA- two factors and Tukey test (p <0.05); the other data were analyzed descriptively. The arrangement of the in-depth charge particles of all the resins involved in this study had an organic matrix rich surface layer and a particulate rich subsurface layer of smaller dimensions. Addicional polishing: reduced surface roughness of Filtek Bulk Fill resins, Vittra APS, Tetric N-ceram Bulk Fill and X-trafil resins; increased the contact angle value of the X-tra Fil and decreased the Filtek Z250 XT. In the analyzes for 3D microtopography and micromorphology, smoother and more uniform surfaces were observed in all a resins. The elements: carbon (C), oxygen (O), silicon (Si), zirconia (Zr) and aluminum (Al) were present in all composite resins. Barium (Ba) was absent on Filtek Z250 XT, Filtek Bulk Fil and Vittra APS. Carbon was predominant in all resins. After additional polishing, there was an increase in oxygen detection for all resins except for Tetric N-Ceram and X-tra Fil and a decrease in carbon except for Tetric N-Ceram Bulk Fil. Silicon decreased only in the Z250 XT, Tetric N-Ceram and Tetric NCeram Bulk Fill resins. Zirconia decreased for Tetric N-Ceram Bulk Fill and aluminum for Z250 XT and Tetric N-Ceram Bulk Fill. Barium increased for Opus Bulk fill and X-tra Fil. Titanium was absent for all resins. Therefore, additional polishing improved the surface properties of the resins studied (AU).
Subject(s)
Microscopy, Electron, Scanning/instrumentation , Wettability , Microscopy, Atomic Force/instrumentation , Composite Resins/chemistry , Dental Polishing , In Vitro Techniques/methods , Analysis of Variance , Dental Materials , Esthetics, Dental , Physical Phenomena , Mouth Rehabilitation摘要
Objective: To investigate the effect of a pediatric syrup containing Amoxicillin on resin-based on the surfaces of resin-based materials under pH cycling. Material and Methods: Cylindrical samples (n=60) of a compomer (Freedom) and a microhybrid composite (TPH Spectrum) were prepared following the manufacturer's instructions. The specimens were divided into two groups and treated for 30min, twice a day, for 14 days with a pediatric syrup containing Amoxicillin, Amoxil™ 500mg/5ml (experimental group) or Distilled water (control group). During the 14 days, the samples were submitted to pH cycling (3h in demineralizing, 20h in remineralizing saliva, and 1h for treatment). The surface roughness was evaluated at baseline, on the 7th and 14th days of erosive challenge using a profilometer and illustrated by SEM. The data were statistically analyzed by one-way ANOVA, Tukey HSD and paired T- tests (p < 0.05). At baseline, the mean Ra TPH = mean Ra F (p > 0.05). Results: After 7 days, it was observed no erosion (p = 0.674) for THP Spectrum (0.19 Ra) and an increasing of Ra (p = 0.02) for Freedom (19.95 Ra). After 14 days, it was observed an increasing of Ra for both THP Spectrum (0.56 Ra) and for Freedom (3.44 Ra), demonstrating that the degradation was treatment and time-dependent (p < 0.001). The pediatric syrup containing Amoxicillin increased the surface roughness of the TPH Spectrum surface one and a half times (p = 0.003) and the surface roughness of Freedom was increased by more than two times (p < 0.001). SEM images showed different aspects of the surfaces of the two materials with a loss of integrity to both. Conclusion: The pediatric syrup containing Amoxicillin under pH cycling increased the roughness of the both tested resin-based restorative materials.