Análise do diâmetro de cones acessórios calibrados por réguas calibradoras / Diameter analysis of accessory cones calibrated by calibrating rulers

O objetivo do presente estudo foi de comparar o diâmetro dos cones acessórios FM EL calibrados por duas réguas calibradoras com seus respectivos diâmetros nominais. Foram calibrados 80 cones de guta percha FM EL (Odous de Deus) utilizando duas réguas calibradoras das seguintes marcas: Prisma e Denco. Os cones foram divididos em 8 grupos (n=10) de acordo com a régua e com o diâmetro em que foram calibrados. Posteriormente, os cones foram fotografados e tiveram seus D0 mensurados através do software ImageJ. Após a realização da análise estatística utilizando-se os testes de Normalidade de Shapiro-Wilk e o teste t Student (Distribuição Normal), obteve-se os seguintes resultados: não houve diferença estatisticamente significativa com o valor de referência na régua prisma nos cones 40, isto é, em todas as outras situações encontrou-se diferença com os valores de referência. Quando foram comparados os valores das medianas e desvio padrão das duas réguas calibradoras também houve diferença estatisticamente significativa (p<0,05) nos cones 25, 35 e 40. Os cones acessórios FM EL (Odous de Deus) calibrados com a régua Denco diferiram dos diâmetros nominais da régua. Assim, deve-se estar atento à exatidão e precisão desses instrumentos a fim de se evitar possíveis erros de mensuração e interpretação capazes de comprometer o êxito da obturação no tratamento endodôntico.

The aim of the present study was to compare the diameter of the FM EL accessory cones calibrated by two calibrating rulers with their respective nominal diameters 80 FM EL gutta percha cones (Odous of God) were calibrated using two calibrating culers of the following brands: Prisma and Denco. The cones were divided in 8 groups (n=10) according to the ruler and the diameter in which they were calibrated. Posteriorly, the cones were photographed and nad their D0 neasured through the software ImageJ. After performing the statistical analysis using the Shapiro- Wilk Normality tests and the Student T test (Normal Distribution), the following results were obtained: there was no stastistically significant difference with the reference value in the prism rule in the cones 40, that is, in all other situations, a difference was found with the reference values. When the median values and standard deviation of the two calibrating rulers were compared, there was also a statistically significant difference (p<0,05) in cones 25, 35 and 40. The FM EL (Odous of God) accessory cones calibrated eita the Denco ruler differed from the nominal diameters of the ruler. Thus, one must pay attention to the accuracy and precision of these instruments in order to avoid possible errors of measurement and interpretation capable of compromising the success of filling in endodontic treatment.

Insect residues as an alternative and promising source for the extraction of chitin and chitosan.

This work aimed to obtain and characterize chitin and chitosan extracted from the rearing residues of Tenebrio molitor, Zophobas morio, and Blaptica dubia insects in different growth stages in the same rearing cycles chitin and chitosan yielded 11.21 %-20.89 % and 6.26 %-7.07 %, respectively. The deacetylation degrees of chitosan ranged from 75.75 %-89.21 %, and the solubilities from 69.88 %-94.39 %. Infrared spectroscopy corroborated the acquisition of chitin and chitosan and can be used as a semi-quantitative technique for determining the degree of chitosan deacetylation. The X-ray diffraction profiles revealed the presence of α-chitin, and the relative crystalline indices ranged from 65.9 %-89.2 %. Typical TG profiles with two thermal events are observed for chitin and chitosan samples with different residue contents from the extraction procedure. The chitosan solutions exhibited pseudoplastic behavior, with apparent viscosities ranging from 195.96 to 249.86 mPa.s. The characterization results of the biopolymers extracted from insect residues were similar to those obtained from conventional sources. The growth stage influenced the chitin yield and crystallinity index. The results of this study reinforce the feasibility of using alternative sources of chitin and chitosan, providing the use of waste from insect farms and contributing to sustainability and a circular economy.