Tooth discoloration induced by endodontic sealers and cervical limit: 1-year in vitro evaluation

Abstract This laboratory study aimed to evaluate the influence of endodontic sealer and cervical limit of root filling on the discoloration of root canal treated teeth. Bovine incisors were randomly distributed into six experimental groups and control (n=21/group), according to the endodontic sealer used [AH Plus (AP); MTA Fillapex (MF) and Sealer Plus BC (SPB)] and the cervical limit of root filling [dental cervix (DC) or 2 mm in apical direction (2mm-AD)]. Tooth discoloration (ΔE) was evaluated by a digital spectrophotometer using the CIED2000 method. Color assessments were performed immediately before (baseline), 1 week, 1, 3, 6 months, and 1 year after obturation. Data were analyzed by ANOVA and Tukey's post-hoc tests (α=5%). Teeth filled with the three sealers showed perceptible tooth discoloration (ΔE≥2.7) in 1 week, maintaining similar values over time. There was a significant difference between MF and SPB sealers in the 2mm-AD groups. In addition, 2mm-AD groups promoted significantly lower discoloration than DC groups for AH (3 months) and SPB (1 and 3 months) sealer,s. Teeth filled with AP, MF, and SPB sealers displayed discoloration from 1 week to one year, with differences between MF and SPB sealers. A cervical limit of filling material at 2 mm from the dental cervix seems more advisable, promoting lower crown discoloration.

Resumo O presente estudo laboratorial teve como objetivo avaliar a influência do cimento endodôntico e do limite cervical da obturação radicular na alteração de cor de dentes tratados endodonticamente. Incisivos bovinos foram distribuídos aleatoriamente em seis grupos experimentais e um controle (n=21/grupo), de acordo com o cimento endodôntico utilizado [AH Plus (AP); MTA Fillapex (MF) e Sealer Plus BC (SPB)] e o limite cervical da obturação [Colo dentário (CD) ou 2mm na direção apical (2mm-DA)]. A alteração de cor (ΔE) foi avaliada por um espectofotômetro digital usando o método CIED2000. As avaliações de cor foram realizadas imediatamente antes (baseline), 1 semana, 1, 3, 6 meses e 1 ano após a obturação. Os dados foram analisados pelos testes ANOVA e post-hoc de Tuckey (α=5%). Dentes obturados com os três cimentos apresentaram alteração de cor perceptível (ΔE≥2.7) em 1 semana, mantendo valores semelhantes ao longo do tempo. Houve uma diferença significativa entre os cimentos MF e SPB nos grupos 2mm-DA. Além disso, os grupos 2mm-DA promoveram uma alteração de cor significativamente menor do que o grupos CD para os cimentos AH (3 meses) e SPB (1 e 3 meses). Os dentes obturados com os cimentos AH, MF e SPB apresentaram alteração de cor entre 1 semana a um ano, com diferenças entre os cimentos MF e SPB. O limite cervical do material obturador a 2mm do colo dentário parece mais aconselhável, promovendo menor alteração de cor da coroa dentária.

A simple method for the determination of bioethanol from lignocellulosic materials using gas chromatography-flame ionisation detector (GC-FID)

Aims@#The utilisation of lignocellulosic biomass for bioethanol production reduces the dependency on fossil fuels as a source of energy and emission of greenhouse gas (GHG). However, studies in this emerging field are hampered by the cost of ethanol quantification methods. Due to the volatile nature of ethanol, the method for the quantification of bioethanol production should be reproducible and rapid to avoid any evaporation loss to the surroundings. Therefore, this study aimed to develop a simple, rapid and precise bioethanol quantification method using a gas chromatographyflame ionisation detector (GC-FID) without having to go through distillation process for ethanol purification.@*Methodology and results@#The bioethanol was produced via consolidated bioprocessing (CBP) using Trichoderma asperellum B1581 and paddy straw. The peak corresponding to ethanol was obtained at 2.347 min with a peak area of 189.66, equating to 0.159% (v/v) or 1.25 g/L ethanol. A comparison between the quantity of ethanol detected by GC-FID and spectrophotometric analysis (340 nm) showed no significant difference (p>0.05) in the amount of ethanol detected by GC analysis, thus validating the accuracy of the GC method.@*Conclusion, significance and impact of study@#This work presents a simple, precise and reliable method to determine the amount of bioethanol in the sample using a GC-FID. Currently, there are many GC-FID methods available for the determination of ethanol/alcohol in a human blood samples or in beverages but not in bioethanol samples. Thus, this method was developed to facilitate the determination of bioethanol in the samples produced from lignocellulosic materials.

Evaluation of the Pharmaceutical Quality of Different Brands of Ranitidine Tablets Manufactured in Bangladesh: A Pharmaceutical and Public Health Prospective.

Drug counterfeiting and production of substandard drug is a global problem. Substandard or counterfeit drugs are threat for the effective treatment of diseases and highly worsen the quality of life of patients. This study was aimed to assess the pharmaceutical quality of ranitidine hydrochloride tablets manufactured in Bangladesh. Tablets were collected from different parts of Bangladesh and quality parameters were evaluated according to the United States Pharmacopoeia and the British Pharmacopoeial methods. The potency of tablets was measured spectrophotometrically. Weight variation and disintegration time were performed according to pharmaceutical monographs. Among 43 brands tested, 8 failed to comply with the USP specification (active ingredient: 90±10%) due to containing of less amount of ranitidine of which 6 brands were spurious and 2 were substandard in nature. Two brands did not comply with the specification for weight variation of tablets whereas all brands passed disintegration time test. The findings clearly demonstrate the production of substandard ranitidine tablets in Bangladesh. The drug control authority of Bangladesh should take effective steps to prevent the production of substandard drugs to secure public health.

Comparação do teor de taninos entre duas espécies de espinheira-santa (Maytenus aquifolium Mart.e Maytenus ilicifolia Mart. ex Reissek)cultivadas no Horto Medicinal do Refúgio Biológico Bela Vista - RBBV da Itaipu Binacional - Foz do Iguaçu, PR - Brasil / Comparison of the tannin doses between two species of thorn-santa (Maytenus ilicifolia Mart. and Maytenus aquifolium Mart. ex Reissek) grown in the medicinal garden of Bela Vista Biological Refuge - RBBV of Itaipu Binational - Foz do Iguacu, PR - Brazil

RESUMO As duas espécies de espinheira-santa Maytenus aquifolium Mart. e Maytenus ilicifolia Mart. ex Reissek pertencentes à família Celastraceae e têm sido intensamente exploradas nas populações nativas devido seu alto valor medicinal. O grande interesse pela espinheira-santa é para o tratamento de gastrites, úlceras gástricas e duodenais. O efeito antiulcerogênico está relacionado com a presença de polifenóis totais, mais especificamente com os taninos. Este trabalho teve como objetivo comparar o teor de taninos entre essas duas espécies cultivadas no Horto Medicinal do Refúgio Biológico Bela Vista - RBBV da Itaipu Binacional no município de Foz do Iguaçu, PR - Brasil. Foram realizadas duas coletas com intervalo de um mês para cada espécie e para a quantificação foi realizada a análise por espectrofotometria segundo a Farmacopeia Brasileira V. Os resultados foram analisados através do teste de variância (ANOVA) e a diferença no teor de taninos foi evidenciada pelo teste Tukey, a 5% de nível de significância empregando-se o software SISVAR. Foram obtidos em média 0,61% para o lote 1 e 2 de Maytenus aquifolium e (3,90%) para Maytenus ilicifolia, resultando em uma média de 84,35% de taninos a mais para Maytenus ilicifolia em comparação com Maytenus aquifolium concluindo assim que as espécies não devem ser intercambiáveis.

ABSTRACT The two species of (espinheira-santa) Maytenus aquifolium and Maytenus ilicifolia, which belong to the Celastraceae family, have been intensively explored in native populations, due to its medicinal potential. The great interest in the espinheira-santa is due to its effectiveness on the treatment of gastritis, gastric and duodenal ulcers. The antiulcerogenic effect is related to the presence of phenolic compounds, more specifically the tannins. This study aimed to compare the tannin doses between these two species grown in the Medicinal Garden of Bela Vista Biological Refuge - RBBV of Itaipu in the city of Foz do Iguaçu, PR - Brazil. Two trials were conducted with one month interval, for the quantification of the tannins by a spectrophotometry, according to the Brazilian Pharmacopoeia V. The results were analyzed through the analysis of variance (ANOVA) and the difference in the tannins doses was demonstrated in a Tukey test at 5% level of significance employing the SISVAR software. It were found 0.61% of tannins for lot 1 and 2 of Maytenus aquifolium, and 3.90% for Maytenus ilicifolia, which represents 84.35% more tannin at Maytenus ilicifolia than at Maytenus aquifolium. Therefore, the species should not be interchanged.

In vitro callus induction and estimation of plumbagin content from Plumbago auriculata Lam.

The medicinal plant Plumbago contains a very potent secondary metabolite, plumbagin having many therapeutic properties. Callus culture was induced using explants, leaf, stem and shoot apex, from P. auriculata. Murashige and Skoog media fortified with various growth hormones like NAA, IAA, IBA and 2, 4-D individually and in various combinations were checked for callus induction. Among the growth hormones used, 1 mg/L 2, 4-D showed best callusing. The hormonal combinations of 1 mg/L IAA and 1.5 mg/L NAA in the media exhibited best callus induction using stem internode as an explant. Plumbagin content from root, stem, leaf and callus was analyzed by using thin layer chromatographic technique. The callus derived from stem showed comparable plumbagin content to the in vivo plant parts. Quantitative spectrophotometric analysis of plumbagin from plant samples and callus indicated that plumbagin content was maximum in roots which was followed by callus, stem and leaf samples respectively. Generation of in vitro sources for plumbagin, for therapeutic applications will serve as a continuous supply and will contribute to preserve the natural plant recourses.

Exploratory study on sequestration of some essential metals by indigo carmine food dye

Indigo carmine forms a stable complex with different ions, and the stability constant of the complexes were evaluated as log K equal to 5.75; 5.00; 4.89 and 3.89 for complexes with Cu(II), Ni(II), Co(II) and Zn(II) ions, respectively, in 0.1 mol L-1 carbonate buffer solution at pH 10. The interaction between Cu(II) ions and indigo carmine (IC) in alkaline medium resulted in the formation of the Cu2(IC) complex, measured by the spectrophotometric method, with a stoichiometric ratio between indigo carmine and metal ions of 2:1 (metal-ligand). The reported method has also been successfully tested for determination of copper in pharmaceutical compounds based on copper-gluconate without pre-treatment.

Índigo carmim forma complexos estáveis com diferentes íons e a constante de estabilidade dos complexos foi avaliada como log K igual 5,75; 5,00; 4,89 e 3,89, respectivamente, para os complexos com os íons Cu(II), Ni(II), Co(II) e Zn(II) em solução tampão carbonato 0,1 mol L-1, pH 10. A interação entre o íon Cu(II) e índigo carmin (IC) em meio alcalino resultou na formação do complexo Cu2(IC) monitorado por método espectrofotométrico, com razão estequiométrica entre o índigo carmim e o íon metálico de 2:1 (metal-ligante). O método relatado também tem sido testado com sucesso para determinação de cobre em compostos farmacêuticos à base de cobre-gliconato sem qualquer pré-tratamento.

Estudo de metodologia analítica para a determinação do cetoconazol em formulações farmacêuticas / Study of analytical methodology for ketoconazole determination in pharmaceutical preparation

Cetoconazol é um antifúngico sintético, derivado imidazólico de amplo espectro de ação, efetivo no tratamento de infecções superficiais e sistêmicas. Foram estudadas diferentes metodologias para análise do cetoconazol em especialidades farmacêuticas diversas usando espectrofotometria no ultravioleta, no infravermelho e análise térmica. Os resultados mostram que a espectrofotometria ultravioleta é um método rápido, prático e econômico e apontam que outros métodos como a espectrofotometria no infravermelho e análise térmica são uma alternativa à análise do cetoconazol em diferentes especialidades farmacêuticas.

Ketoconazole is a synthetic broad-spectrum oral and topical antifungal drug derived from imidazole, effective in the treatment of superficial mycoses and systemic infections. In this study we have tested several methods to analyze ketoconazole in various pharmaceutical products containing this drug, employing techniques such as UV and IR spectrophotometry and thermal analysis. The results showed that UV spectrophotometryis a fast, practical and economical method and indicated that other methods, such as IR spectrophotometry and thermal analysis, could be good alternative methods for ketoconazole analysis in certain pharmaceutical forms.

Spectrophotometric evaluation of sealing effects of several root-end filling materials / 대한치과보존학회지

The purpose of this study is to evaluate the sealing effect of several root-end filling materials using spectrophotometric analysis. 180 single root teeth with one canal were instrumented and canal filled. Root resected and root end preparation was made. Teeth were randomly classified to 5 experimental group(MTA, EBA, IRM, TCP, ZOE) and 1 control group according to root-end filling material MTA group used PRO ROOT MTA, EBA group used Super EBA, TCP group used NEW APATITE LINER TYPE II main component of which is alpha-tricalcium phosphate(TCP). According to manufacture's instruction experimental material was mixed and retrfilled. After 2% methylene blue solution penetration absorbance for each test sample was measured with spectrophotometer (JASCO UV-530, Japan). The mean absorbance of control and experimental group was as follows; MTA : 0.092, IRM : 0.226, Super EBA : 0.255, ZOE : 0.374, Control : 0.425, TCP : 0.501 and the result analyzed by Turkey test at P=0.05 level. Conclusions of this study are as follows; 1. The absorbance increase in follwing sequence MTA, IRM, Super EBA, ZOE, Control, TCP. 2. MTA showed the least leakage but was not significant with IRM or Super EBA and was significant with control or TCP(p<0.05). 3. TCP had the most leakage and was not significant with control group.

STUDY ON THE DETERMINATION OF ALOE OLIGOSACCHARIDES / 营养学报

Objective: To develop a stable and simple method to measure the content of aloe oligosaccharides. Methods: After the conversion coefficient of aloe oligosaccharides to glucose was obtained, the content of aloe oligosaccharides was measured by phenol sulfuric acid method. Results: The correlation coefficient of standard curve is 0.9993, the recovery rate is 95.3% and RSD is 1.23%. Conclusion: The method can be applied to aloe and aloe products.