Evaluation of resin composite polymerization by three dimensional micro-CT imaging and nanoindentation

The aim of the study was to determine the marginal and internal adaptation after curing of different composite resin restorations, using a nondestructive X-ray micro-computed tomography (micro-CT). Forty previously extracted human molars, kept in 10% formalin to preserve the bonding capabilities of the tooth structures, were divided into four groups based on the composite system used and different light-curing times. Class II (vertical slot) cavities were prepared on one proximal side and restored with dental composite using a Tofflemire matrix, with a bulk-fill composite resin (Venus Bulk Fill, Heraeus Kulzer) and a universal posterior composite (G-ænial Posterior, GC). A curing lamp (Kerr Demi Ultra) was used with different curing times. Micro-CT scanning was performed by using Nikon XTH 225ST to reveal any defects in adaptation or gaps at the tooth restoration interface. The 3D images of the adaptation around the restorations were reconstructed using VG Studio Max 2.2 and myVGL 2.2.6 64-bit software. All samples from the G-ænial group showed marginal and internal gaps, with G-ænial Posterior having higher polymerization shrinkage and marginal gap values. In the Venus Bulk Fill group, there were fewer restorations with internal and external gap formation. Micro-CT is a three-dimensional imaging technique that can nondestructively detect adaptation around the resin composite restorations at every level of the sample.

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Nondestructive cryomicro-CT imaging enables structural and molecular analysis of human lung tissue

Journal of Applied Physiology ◽

10.1152/japplphysiol.00838.2016 ◽

2017 ◽

Vol 122 (1) ◽

pp. 161-169 ◽

Cited By ~ 16

Author(s):

Dragoş M. Vasilescu ◽

André B. Phillion ◽

Naoya Tanabe ◽

Daisuke Kinose ◽

David F. Paige ◽

...

Keyword(s):

Molecular Analysis ◽

Structural Changes ◽

Human Lung ◽

Three Dimensional ◽

Ct Imaging ◽

Matrix Composition ◽

Micro Ct ◽

Micro Computed Tomography ◽

Human Lung Tissue ◽

Lung Structure

Micro-computed tomography (CT) enables three-dimensional (3D) imaging of complex soft tissue structures, but current protocols used to achieve this goal preclude cellular and molecular phenotyping of the tissue. Here we describe a radiolucent cryostage that permits micro-CT imaging of unfixed frozen human lung samples at an isotropic voxel size of (11 µm)3 under conditions where the sample is maintained frozen at −30°C during imaging. The cryostage was tested for thermal stability to maintain samples frozen up to 8 h. This report describes the methods used to choose the materials required for cryostage construction and demonstrates that whole genome mRNA integrity and expression are not compromised by exposure to micro-CT radiation and that the tissue can be used for immunohistochemistry. The new cryostage provides a novel method enabling integration of 3D tissue structure with cellular and molecular analysis to facilitate the identification of molecular determinants of disease. NEW & NOTEWORTHY The described micro-CT cryostage provides a novel way to study the three-dimensional lung structure preserved without the effects of fixatives while enabling subsequent studies of the cellular matrix composition and gene expression. This approach will, for the first time, enable researchers to study structural changes of lung tissues that occur with disease and correlate them with changes in gene or protein signatures.

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IN-VITRO ANALYSIS OF MAXILLARY FIRST MOLARS MORPHOLOGY USING THREE DIMENSIONAL MICRO-CT IMAGING: CONSIDERATIONS FOR RESTORATIVE DENTISTRY

Journal of Istanbul University Faculty of Dentistry ◽

10.17096/jiufd.61722 ◽

2017 ◽

Vol 0 (0) ◽

Author(s):

İsmail Hakkı Baltacıoğlu ◽

Gülbike Demirel ◽

Mehmet Eray Kolsuz ◽

Kaan Orhan

Keyword(s):

Three Dimensional ◽

Ct Imaging ◽

Micro Ct ◽

Restorative Dentistry ◽

Vitro Analysis ◽

In Vitro Analysis

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Scalable method for micro-CT analysis enables large scale quantitative characterization of brain lesions and implants

Scientific Reports ◽

10.1038/s41598-020-77796-3 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

David B. Kastner ◽

Viktor Kharazia ◽

Rhino Nevers ◽

Clay Smyth ◽

Daniela A. Astudillo-Maya ◽

...

Keyword(s):

Brain Structure ◽

Large Scale ◽

Three Dimensional ◽

Ct Imaging ◽

Nondestructive Method ◽

Brain Lesions ◽

Dimensional Structure ◽

Micro Ct ◽

Ct Analysis ◽

Quantitative Analyses

AbstractAnatomic evaluation is an important aspect of many studies in neuroscience; however, it often lacks information about the three-dimensional structure of the brain. Micro-CT imaging provides an excellent, nondestructive, method for the evaluation of brain structure, but current applications to neurophysiological or lesion studies require removal of the skull as well as hazardous chemicals, dehydration, or embedding, limiting their scalability and utility. Here we present a protocol using eosin in combination with bone decalcification to enhance contrast in the tissue and then employ monochromatic and propagation phase-contrast micro-CT imaging to enable the imaging of brain structure with the preservation of the surrounding skull. Instead of relying on descriptive, time-consuming, or subjective methods, we develop simple quantitative analyses to map the locations of recording electrodes and to characterize the presence and extent of hippocampal brain lesions.

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Detection of Marginal Leakage of Class V Restorations In Vitro by Micro–Computed Tomography

Operative Dentistry ◽

10.2341/12-182-l ◽

2014 ◽

Vol 39 (2) ◽

pp. 174-180 ◽

Cited By ~ 13

Author(s):

XY Zhao ◽

SB Li ◽

LJ Gu ◽

Y Li

Keyword(s):

Computed Tomography ◽

Resin Composite ◽

Nitrate Solution ◽

Three Dimensional ◽

Micro Ct ◽

Micro Computed Tomography ◽

Class V ◽

Enamel Structure ◽

Significant Difference

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.

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Scalable method for micro-CT analysis enables large scale quantitative characterization of brain lesions and implants

10.1101/2020.03.12.989871 ◽

2020 ◽

Author(s):

David B. Kastner ◽

Viktor Kharazia ◽

Rhino Nevers ◽

Daniela A. Astudillo-Maya ◽

Greer M. Williams ◽

...

Keyword(s):

Brain Structure ◽

Large Scale ◽

Three Dimensional ◽

Ct Imaging ◽

Nondestructive Method ◽

Brain Lesions ◽

Dimensional Structure ◽

Micro Ct ◽

Ct Analysis ◽

Quantitative Analyses

AbstractAnatomic evaluation is an important aspect of many studies in neuroscience; however, it often lacks information about the three-dimensional structure of the brain. Micro-CT imaging provides an excellent, nondestructive, method for the evaluation of brain structure, but current applications to neurophysiological or lesions studies require removal of the skull and hazardous chemicals, dehydration or embedding, limiting their scalability and utility. Here we present a protocol using eosin in combination with bone decalcification to enhance contrast in the tissue and then employ monochromatic and propagation phase-contrast micro-CT imaging to enable the imaging of brain structure with the preservation of the surrounding skull. Instead of relying on descriptive, time-consuming, or subjective methods, we develop simple quantitative analyses to map the locations of recording electrodes and to characterize the presence and extent of brain lesions.

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