Micro-Computed Tomography as a Tool to Investigate the Deformation Behavior of Particulate-Filled Composite Materials

2017 ◽  
Vol 140 (2) ◽  
Author(s):  
Kenan Cinar ◽  
Ibrahim Guven
Keyword(s):  
Computed Tomography ◽  
Composite Materials ◽  
Displacement Field ◽  
Deformation Behavior ◽  
Mass Fraction ◽  
Indentation Test ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Before And After ◽  
Filled Composite

Micro-computed tomography (CT) was used as a tool to investigate the deformation behavior of particulate-filled composite materials. Three different shapes of glass fillers (spherical, flake, and fiber) and filler mass fractions (5%, 10%, and 15%) were introduced to the epoxy resin. Rockwell hardness H scale indentation test was used to deform the composite material. The composite materials were scanned before and after the indentation test by using micro-CT. Displacement field for each filler type and mass fraction were measured through correlation of before and after scan data. The effects of filler type and mass fraction on the internal displacement field were investigated. It was also demonstrated that micro-CT can be used as a tool to create realistic representative volume elements (RVEs) for particulate-filled composite materials instead of randomly distributed particles within the matrix material.

scholarly journals Influence of the calcium hydroxide paste vehicle on penetration into lateral canals

2018 ◽  
Vol 21 (3) ◽  
pp. 282
Author(s):  
Amanda Sousa Vidal ◽  
Daniele Aparecida Leão ◽  
Fernanda Mota Guimarães ◽  
Mariana Oliveira Gonçalves ◽  
Raissa Freitas Pinheiro ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Calcium Hydroxide ◽  
Propylene Glycol ◽  
Group Analysis ◽  
Distilled Water ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Respective Group ◽  
Before And After

<p><strong>Objective: </strong>The aim of this study was to use Micro computed tomography (micro-CT) to evaluate the influence of the type of vehicle associated with calcium hydroxide on its ability to penetrate simulated lateral canals. <strong>Materials and methods:</strong> 30 acrylic blocks with simulated lateral canals comprising apical, middle and cervical thirds were used in the <em>in vitro</em> study. The blocks were divided into 3 groups (n = 10) according to the type of vehicle used (chlorhexidine, distilled water and propylene glycol) in the calcium hydroxide slurry, which was inserted in the respective group of simulated canals with a K# 30 file and then agitated with an ultrasonic tip. The blocks were scanned by micro-computed tomography (micro-CT) before and after insertion of the medication. The images obtained were reconstructed and analyzed to obtain the initial volume of lateral canals and the volume of medication that penetrated into them. <strong>Results:</strong> In the intragroup analysis, both distilled water and chlorhexidine 2% were observed to present statistical difference in all thirds of the canal. Propylene glycol showed no intragroup difference. In the inter-group analysis, the propylene glycol paste presented higher values of penetration into the simulated lateral canals than the other groups (p &lt;0.05). <strong>Conclusion:</strong> Propylene glycol used as vehicle of the calcium hydroxide paste provided better penetration results in simulated lateral canals.</p>

scholarly journals A micro-computed tomography evaluation of the change in volume of different bulk-fill composite materials caused by polymerization shrinkage

2021 ◽  
Vol 11 (2) ◽  
pp. 75-82
Author(s):  
Suzan Cangül ◽  
Özkan Adıgüzel ◽  
Savaş Sağmak ◽  
Begüm Evran
Keyword(s):  
Computed Tomography ◽  
Composite Materials ◽  
Class Ii ◽  
Ct Images ◽  
Composite Resins ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Dental Tissue ◽  
Polymerization Shrinkage ◽  
Native Speakers Of English

Aim: Composite resins contain different monomers and fillers that are directly affected by polymerization shrinkage.  Therefore, an accurate and reliable method is needed to measure the volume changes. The aim of this study was to evaluate the amount of volume change associated with polymerization shrinkage in four different bulk-fill composite materials in class II restorations using a micro-CT device, which has high resolution and provides 3-dimensional images. Methodology: A total of 40 human 3rd molar teeth were used. First, standard class II cavities were opened on the mesial surfaces of all the teeth, and then the first micro-CT images were obtained. The same adhesive material was applied to all the teeth. The teeth were then separated into four groups, and a different bulk-fill composite was applied to each group; Filtek (FTK), X-tra Fil (XTF), Tetric Evo Ceram (TEC), and Filtek One (FLO) and the second micro-CT images were obtained. Then after polymerization of the materials, the final micro-CT images were taken, and analyses were made according to the scanning results. The Kruskal Wallis and Mann Whitney U-tests were used in the statistical evaluation of the data.  Results: The volumetric gap formed after polymerization of the composite resins was not determined to be statistically significant (p>0.05). Conclusion: The volumetric difference (%) between the composite resin and the dental tissue following polymerization was seen to be greatest in XTF and least in FTK. It was concluded that the volumetric gap caused by the polymerization shrinkage of the tested materials may be due to the structure of the material.   How to cite this article: Cangül S, Adıgüzel Ö, Sağmak S, Evran B. A micro-computed tomography evaluation of the change in volume of different bulk-fill composite materials caused by polymerization shrinkage. Int Dent Res 2021;11(2):75-82. https://doi.org/10.5577/intdentres.2021.vol11.no2.4   Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.  

scholarly journals Micro-Computed Tomography Analysis of Subchondral Bone Regeneration Using Osteochondral Scaffolds in an Ovine Condyle Model

2021 ◽  
Vol 11 (3) ◽  
pp. 891
Author(s):  
Taylor Flaherty ◽  
Maryam Tamaddon ◽  
Chaozong Liu
Keyword(s):  
Computed Tomography ◽  
Bone Regeneration ◽  
Subchondral Bone ◽  
Volume Ratio ◽  
Bone Volume ◽  
Osteochondral Defects ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Trabecular Thickness ◽  
Osteochondral Scaffold

Osteochondral scaffold technology has emerged as a promising therapy for repairing osteochondral defects. Recent research suggests that seeding osteochondral scaffolds with bone marrow concentrate (BMC) may enhance tissue regeneration. To examine this hypothesis, this study examined subchondral bone regeneration in scaffolds with and without BMC. Ovine stifle condyle models were used for the in vivo study. Two scaffold systems (8 mm diameter and 10 mm thick) with and without BMC were implanted into the femoral condyle, and the tissues were retrieved after six months. The retrieved femoral condyles (with scaffold in) were examined using micro-computed tomography scans (micro-CT), and the micro-CT data were further analysed by ImageJ with respect to trabecular thickness, bone volume to total volume ratio (BV/TV) ratio, and degree of anisotropy of bone. Statistical analysis compared bone regeneration between scaffold groups and sub-set regions. These results were mostly insignificant (p < 0.05), with the exception of bone volume to total volume ratio when comparing scaffold composition and sub-set region. Additional trends in the data were observed. These results suggest that the scaffold composition and addition of BMC did not significantly affect bone regeneration in osteochondral defects after six months. However, this research provides data which may guide the development of future treatments.

scholarly journals Using micro-computed tomography to reveal the anatomy of adult Diaphorina citri Kuwayama (Insecta: Hemiptera, Liviidae) and how it pierces and feeds within a citrus leaf

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Javier Alba-Tercedor ◽  
Wayne B. Hunter ◽  
Ignacio Alba-Alejandre
Keyword(s):  
Computed Tomography ◽  
Significant Advance ◽  
Micro Ct ◽  
Diaphorina Citri ◽  
Ct Reconstruction ◽  
Internal Anatomy ◽  
Micro Computed Tomography ◽  
Citrus Leaf ◽  
Teaching Aids ◽  
Adult Feeding

AbstractThe Asian citrus psyllid (ACP), Diaphorina citri, is a harmful pest of citrus trees that transmits Candidatus Liberibacter spp. which causes Huanglongbing (HLB) (citrus greening disease); this is considered to be the most serious bacterial disease of citrus plants. Here we detail an anatomical study of the external and internal anatomy (excluding the reproductive system) using micro-computed tomography (micro-CT). This is the first complete 3D micro-CT reconstruction of the anatomy of a psylloid insect and includes a 3D reconstruction of an adult feeding on a citrus leaf that can be used on mobile devices. Detailed rendered images and videos support first descriptions of coxal and scapus antennal glands and sexual differences in the internal anatomy (hindgut rectum, mesothoracic ganglion and brain). This represents a significant advance in our knowledge of ACP anatomy, and of psyllids in general. Together the images, videos and 3D model constitute a unique anatomical atlas and are useful tools for future research and as teaching aids.

scholarly journals Effects of pre-extraction intermittent PTH administration on extraction socket healing in bisphosphonate administered ovariectomized rats

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jae-Young Kim ◽  
Hyo-Won Jang ◽  
Jung-In Kim ◽  
In-Ho Cha
Keyword(s):  
Tooth Extraction ◽  
Bisphosphonate Therapy ◽  
Ovariectomized Rats ◽  
Control Group ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Extraction Socket ◽  
Before And After ◽  
Socket Healing ◽  
Positive Effect

AbstractThe purpose of this study was to investigate the effect of administering intermittent parathyroid hormone (iPTH) before tooth extraction versus after tooth extraction on the risk of developing MRONJ in experimental animal model. Twenty-five ovariectomized rats received 6 weeks of bisphosphonate therapy. They were classified into 3 groups, based on the timing of the medication, as Control, Pre-PTH and Post-PTH groups. For Control group, normal saline was administered before and after tooth extraction. iPTH was administered during 4 weeks before tooth extraction for Pre-PTH group and after tooth extraction for Post-PTH group. The animals were euthanized 8 weeks after tooth extraction. Macroscopic, histological, micro-computed tomography (micro-CT), and histomorphometric examinations were conducted. The incidences of impaired healing were 11.11% both in Pre-PTH and Post-PTH groups, which was lower than the Control group (42.86%). Bone healing in the extraction socket, based on micro-CT and histomorphometry evaluations, was best in Post-PTH and worst in Control group. The Pre-PTH group showed moderate healing pattern. Despite of limitations in this study, the authors identified Pre-PTH group seems to have positive effect on extraction socket healing. With regard to timing, administering iPTH after tooth extraction was superior to applying it before tooth extraction.

MicroCT protocols for scanning of embryos and juvenile Hexaplex trunculus v1

2021 ◽  
Author(s):  
Eva Chatzinikolaou ◽  
Kleoniki Keklikoglou
Keyword(s):  
Computed Tomography ◽  
High Resolution ◽  
3D Imaging ◽  
Imaging Technique ◽  
Ct Scanning ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Gastropod Species ◽  
Biological Studies ◽  
Hexaplex Trunculus

Micro-computed tomography (micro-CT) is a high-resolution 3D-imaging technique which is now increasingly applied in biological studies focusing on taxonomy and functional morphology. The creation of virtual representations of specimens can increase availability of otherwise underexploited and inaccessible samples. This protocol aims to standardise micro-CT scanning procedures for embryos and juveniles of the marine gastropod species Hexaplex trunculus.

scholarly journals Micro-Computed Tomography (Micro-CT) Evaluation of Effects of Different Rotary Glide Path Techniques on Canal Transportation and Centering in Curved Root Canals

2019 ◽  
Vol 25 ◽  
pp. 6351-6358
Author(s):  
Gabrielė Česaitienė ◽  
Tadas Venskutonis ◽  
Vita Mačiulskienė ◽  
Vaidotas Cicėnas ◽  
Vykintas Samaitis ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Root Canals ◽  
Glide Path ◽  
Ct Evaluation ◽  
Canal Transportation ◽  
Curved Root Canals

Quantitative micro-computed tomography analysis and rheological investigation of Nitrile rubber/Rockwool composites

2021 ◽  
pp. 002199832110338
Author(s):  
Elisson BD da Rocha ◽  
Ana Maria F de Sousa ◽  
Ana Lúcia N da Silva ◽  
Cristina RG Furtado ◽  
Marcos V Colaço ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Elastic Modulus ◽  
Aspect Ratio ◽  
Volume Fraction ◽  
Nitrile Rubber ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Rubber Composites ◽  
Ratio Data ◽  
Ct Analysis

This study reports the reinforcement degree investigation of two types of rockwool fibers (F1 and F2), in nitrile rubber composites. The micro-computed tomography (micro-CT) 3D images showed that both fibers were well-dispersed in the NBR matrix, without a preferential orientation. The micro-CT analysis also allowed quantifying volume fraction, inter-fiber distance, and aspect ratio. Those morphometric parameters were used for supporting the composites rheological behavior assessment. Changes in the elastic modulus and phase angle followed the same trend of the inter-fiber distance values, regardless the type of fiber. Both volume fraction and aspect ratio data from the micro-CT analysis were used to predict theoretical values of elastic modulus using the Guth-Gold and modified Guth-Gold equations, and the results obtained were compared to the rheological experimental data. This analysis was helpful to better understand the rockwool fibers reinforcement degree differences in the production of the nitrile rubber composites.

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