Three-Dimensional Quantification of Calcium Salt-Composite Resorption (CSC) In Vitro by Micro-computed Tomography (Micro-CT)

JOM ◽  
2014 ◽  
Vol 66 (4) ◽  
pp. 559-565 ◽  
Author(s):  
T. Winkler ◽  
X. Y. Dai ◽  
G. Mielke ◽  
S. Vogt ◽  
H. Buechner ◽  
...  
2014 ◽  
Vol 39 (2) ◽  
pp. 174-180 ◽  
Author(s):  
XY Zhao ◽  
SB Li ◽  
LJ Gu ◽  
Y Li

SUMMARY This in vitro study evaluated the efficacy of micro–computed tomography (CT) in marginal leakage detection of Class V restorations. Standardized Class V preparations with cervical margins in dentin and occlusal margins in enamel were made in 20 extracted human molars and restored with dental bonding agents and resin composite. All teeth were then immersed in 50% ammoniacal silver nitrate solution for 12 hours, followed by a developing solution for eight hours. Each restoration was scanned by micro-CT, the depth of marginal silver leakage in the central scanning section was measured, and the three-dimensional images of the silver leakage around each restoration were reconstructed. Afterward, all restorations were cut through the center and examined for leakage depth using a microscope. The silver leakage depth of each restoration obtained by the micro-CT and the microscope were compared for equivalency. The silver leakage depth in cervical walls observed by micro-CT and microscope showed no significant difference; however, in certain cases the judgment of leakage depth in the occlusal wall in micro-CT image was affected by adjacent enamel structure, providing less leakage depth than was observed with the microscope (p<0.01). Micro-CT displayed the three-dimensional image of the leakage around the Class V restorations with clear borders only in the dentin region. It can be concluded that micro-CT can detect nondestructively the leakage around a resin composite restoration in two and three dimensions, with accuracy comparable to that of the conventional microscope method in the dentin region but with inferior accuracy in the enamel region.


2018 ◽  
Vol 21 (3) ◽  
pp. 282
Author(s):  
Amanda Sousa Vidal ◽  
Daniele Aparecida Leão ◽  
Fernanda Mota Guimarães ◽  
Mariana Oliveira Gonçalves ◽  
Raissa Freitas Pinheiro ◽  
...  

<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>


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Charmainne Cruje ◽  
P. Joy Dunmore-Buyze ◽  
Eric Grolman ◽  
David W. Holdsworth ◽  
Elizabeth R. Gillies ◽  
...  

AbstractVascular research is largely performed in rodents with the goal of developing treatments for human disease. Micro-computed tomography (micro-CT) provides non-destructive three-dimensional imaging that can be used to study the vasculature of rodents. However, to distinguish vasculature from other soft tissues, long-circulating contrast agents are required. In this study, we demonstrated that poly(ethylene glycol) (PEG)-coated gadolinium nanoparticles can be used as a vascular contrast agent in micro-CT. The coated particles could be lyophilized and then redispersed in an aqueous solution to achieve 100 mg/mL of gadolinium. After an intravenous injection of the contrast agent into mice, micro-CT scans showed blood pool contrast enhancements of at least 200 HU for 30 min. Imaging and quantitative analysis of gadolinium in tissues showed the presence of contrast agent in clearance organs including the liver and spleen and very low amounts in other organs. In vitro cell culture experiments, subcutaneous injections, and analysis of mouse body weight suggested that the agents exhibited low toxicity. Histological analysis of tissues 5 days after injection of the contrast agent showed cytotoxicity in the spleen, but no abnormalities were observed in the liver, lungs, kidneys, and bladder.


2020 ◽  
Vol 94 (3) ◽  
pp. 417-435 ◽  
Author(s):  
Sarah Kachovich ◽  
Jonathan C. Aitchison

AbstractA new, previously undescribed Middle Ordovician (middle Darriwilian: Dw2) radiolarian assemblage has been recovered from the Table Cove Formation at Piccadilly Quarry, western Newfoundland. Constituents of the fauna described herein are both distinctive and exceptionally well preserved. Three-dimensional X-ray micro-computed tomography (μ-CT) is used to make a detailed examination of four key spumellarian specimens. This technology enables visualization of hitherto ambiguous details of the internal morphologies of key lower Paleozoic taxonomic groups, among which a lack of knowledge has impeded resolution of higher taxonomic rankings.


2021 ◽  
Vol 09 (12) ◽  
pp. E1886-E1889
Author(s):  
Noboru Kawata ◽  
Alexei Teplov ◽  
Peter Ntiamoah ◽  
Jinru Shia ◽  
Meera Hameed ◽  
...  

AbstractMicro-computed tomography (micro-CT) is a non-destructive modality that can be used to obtain high-resolution three-dimensional (3 D) images of the whole sample tissue; the usefulness of micro-CT has been reported for evaluation of breast cancer and lung cancer. However, this novel diagnostic technique has never been used for evaluating endoscopically resected gastrointestinal specimens. In the present study, we scanned 13 formalin-fixed paraffin-embedded (FFPE) tissue blocks of a normal human colon and gastric tissue samples using micro-CT. The evaluation comprised a comparison of the acquired whole block images with the images of the corresponding cross-sectional slice of the hematoxylin and eosin-stained slide. Micro-CT was able to produce images of the whole sample and clearly depict tissues such as glandular structures, muscularis mucosae, and blood vessels in the FFPE tissue blocks of normal gastrointestinal samples. Furthermore, the 3 D reconstructed could be used to create a cross-sectional image and reflected the surface structure of samples obtained from any site. Micro-CT has the potential to become a highly promising pathological diagnostic assistance tool for endoscopically resected gastrointestinal specimens in combination with conventional microscopic examination.


2020 ◽  
Vol 143 (1) ◽  
Author(s):  
Muhammad Jawad Munawar ◽  
Sandra Vega ◽  
Chengyan Lin ◽  
Mohammad Alsuwaidi ◽  
Naveed Ahsan ◽  
...  

Abstract Scaling porosity of sedimentary rocks from the scale of measurement to the scale of interest is still a challenge. Upscaling of porosity can assist to accurately predict other petrophysical properties of rock at multiple scales. In this study, we use the two-dimensional (2D) scanning electron microscope (SEM) and three-dimensional (3D) X-ray micro-computed tomography (micro-CT) image to upscale porosity from the image scale to the core plug scale. A systematic imaging plan is deployed to capture rock properties of a carbonate and a sandstone sample, which are sensitive to the fractal nature of these rocks. Image analysis records wider pore spectrum (0.12–50 µm) in the carbonate sample than in sandstone (0.12–30 µm). The fractal dimensions are also higher in the carbonate than in the sandstone sample. Median, volume-weighted average of pore radius, and fractal dimensions derived from the image analysis are used as inputs in this equation. The results of the present study using this equation yielded to the best results on a resolution of 2.5 µm/voxel in the sandstone and 2.01 µm/voxel resolution in the carbonate sample for 3D micro-CT images, where fractal-scaling porosity matches well with the porosity measured at the core plug scale. The 2D SEM images provided a good estimation of porosity in the sandstone sample, where micro-CT imaging techniques could not capture the full pore spectrum. The fractal porosity equation showed promising results and offers a potential alternative way to estimate porosity when there are no routine core measurements available.


2020 ◽  
Vol 17 (165) ◽  
pp. 20200102
Author(s):  
Aleksi Palmroth ◽  
Sanna Pitkänen ◽  
Markus Hannula ◽  
Kaarlo Paakinaho ◽  
Jari Hyttinen ◽  
...  

Micro-computed tomography (micro-CT) provides a means to analyse and model three-dimensional (3D) tissue engineering scaffolds. This study proposes a set of micro-CT-based tools firstly for evaluating the microstructure of scaffolds and secondly for comparing different cell seeding methods. The pore size, porosity and pore interconnectivity of supercritical CO 2 processed poly( l -lactide-co- ɛ -caprolactone) (PLCL) and PLCL/β-tricalcium phosphate scaffolds were analysed using computational micro-CT models. The models were supplemented with an experimental method, where iron-labelled microspheres were seeded into the scaffolds and micro-CT imaged to assess their infiltration into the scaffolds. After examining the scaffold architecture, human adipose-derived stem cells (hASCs) were seeded into the scaffolds using five different cell seeding methods. Cell viability, number and 3D distribution were evaluated. The distribution of the cells was analysed using micro-CT by labelling the hASCs with ultrasmall paramagnetic iron oxide nanoparticles. Among the tested seeding methods, a forced fluid flow-based technique resulted in an enhanced cell infiltration throughout the scaffolds compared with static seeding. The current study provides an excellent set of tools for the development of scaffolds and for the design of 3D cell culture experiments.


2011 ◽  
Vol 92 (2) ◽  
pp. 104-111 ◽  
Author(s):  
Cheryl R. Hann ◽  
Michael D. Bentley ◽  
Andrew Vercnocke ◽  
Erik L. Ritman ◽  
Michael P. Fautsch

2007 ◽  
Vol 6 (4) ◽  
pp. 7290.2007.00022 ◽  
Author(s):  
Cristian T. Badea ◽  
Laurence W. Hedlund ◽  
Julie F. Boslego Mackel ◽  
Lan Mao ◽  
Howard A. Rockman ◽  
...  

The purpose of this study was to investigate the use of micro–computed tomography (micro-CT) for morphological and functional phenotyping of muscle LIM protein (MLP) null mice and to compare micro-CT with M-mode echocardiography. MLP null mice and controls were imaged using both micro-CT and M-mode echocardiography. For micro-CT, we used a custom-built scanner. Following a single intravenous injection of a blood pool contrast agent (Fenestra VC, ART Advanced Research Technologies, Saint-Laurent, QC) and using a cardiorespiratory gating, we acquired eight phases of the cardiac cycle (every 15 ms) and reconstructed three-dimensional data sets with 94-micron isotropic resolution. Wall thickness and volumetric measurements of the left ventricle were performed, and cardiac function was estimated. Micro-CT and M-mode echocardiography showed both morphological and functional aspects that separate MLP null mice from controls. End-diastolic and -systolic volumes were increased significantly three- and fivefold, respectively, in the MLP null mice versus controls. Ejection fraction was reduced by an average of 32% in MLP null mice. The data analysis shows that two imaging modalities provided different results partly owing to the difference in anesthesia regimens. Other sources of errors for micro-CT are also analyzed. Micro-CT can provide the four-dimensional data (three-dimensional isotropic volumes over time) required for morphological and functional phenotyping in mice.


Sign in / Sign up

Export Citation Format

Share Document