Ten Years of Micro-CT in Dentistry and Maxillofacial Surgery: A Literature Overview

Micro-computed tomography (micro-CT) is a consolidated imaging technology allowing non-destructive three-dimensional (3D) qualitative and quantitative analysis by the observation of microstructures with high resolution. This paper aims at delivering a structured overview of literature about studies performed using micro-CT in dentistry and maxillofacial surgery (MFS) by analyzing the entire set of articles to portray the state of the art of the last ten years of scientific publications on the topic. It draws the scenario focusing on biomaterials, in vitro and in/ex vivo applications, bone structure analysis, and tissue engineering. It confirms the relevance of the micro-CT analysis for traditional research applications and mainly in dentistry with respect to MFS. Possible developments are discussed in relation to the use of the micro-CT combined with other, traditional, and not, techniques and technologies, as the elaboration of 3D models based on micro-CT images and emerging numerical methods. Micro-CT results contribute effectively with whose ones obtained from other techniques in an integrated multimethod approach and for multidisciplinary studies, opening new possibilities and potential opportunities for the next decades of developments.

Download Full-text

Micro-CT analysis of two-dimensional and three-dimensional parameters in severely curved roots prepared with 3 instrumentation systems: An in vitro study

European Journal of General Dentistry ◽

10.4103/ejgd.ejgd_140_19 ◽

2020 ◽

Vol 9 (2) ◽

pp. 62

Author(s):

AntonioMiranda da Cruz-Filho ◽

LuisEduardo Souza-Flamini ◽

BrunoMonguilhott Crozeta ◽

RicardoGariba Silva ◽

RicardoNovak Savioli ◽

...

Keyword(s):

Three Dimensional ◽

In Vitro Study ◽

Vitro Study ◽

Two Dimensional ◽

Micro Ct ◽

Ct Analysis ◽

Dimensional Parameters

Download Full-text

PEG-modified gadolinium nanoparticles as contrast agents for in vivo micro-CT

Scientific Reports ◽

10.1038/s41598-021-95716-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Charmainne Cruje ◽

P. Joy Dunmore-Buyze ◽

Eric Grolman ◽

David W. Holdsworth ◽

Elizabeth R. Gillies ◽

...

Keyword(s):

Contrast Agent ◽

Contrast Agents ◽

Soft Tissues ◽

Three Dimensional ◽

Blood Pool ◽

Micro Ct ◽

Micro Computed Tomography ◽

Poly Ethylene

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.

Download Full-text

StyroStone: A protocol for scanning and extracting three-dimensional meshes of stone artefacts using Micro-CT scanners v1

10.17504/protocols.io.bzbfp2jn ◽

2021 ◽

Author(s):

Dominik Göldner ◽

Fotios Alexandros Karakostis ◽

Armando Falcucci

Keyword(s):

Three Dimensional ◽

Computation Time ◽

Ct Scanning ◽

3D Models ◽

Stone Tools ◽

Surface Model ◽

Micro Ct ◽

Ct Scanner ◽

Micro Computed Tomography ◽

Ct Scanners

This protocol presents the first detailed step-by-step pipeline for the 3D scanning and post processing of large batches of lithic artefacts using a micro-computed tomography (micro-CT) scanner (i.e., a Phoenix v-tome-x S model by General Electronics MCC, Boston MA) and an Artec Space Spider scanner (Artec Inc., Luxembourg). This protocol was used to scan and analyze ca. 700 lithic artefacts from the Protoaurignacian layers at Fumane Cave in north-eastern Italy (Falcucci et al., in preparation). For this study several costly scanners and proprietary software packages were employed. Although it is not easy to find a low-budget alternative for the scanners, it is possible to use free and open-source software programs, such as 3D-Slicer (https://www.slicer.org/) or MorphoDig (https://morphomuseum.com/morphodig), to process CT data as well as MeshLab (Cignoni et al. 2008) to interact with the 3D models in general. However, if alternative software is used, the steps and their order described in this protocol might diverge significantly. A cost-effective alternative to create 3D models is digital photogrammetry using commercial cameras and freely available software like Meshroom (https://alicevision.org). Although photogrammetry is an affordable technique to create accurate 3D models of objects, this method might not be useful when scanning large batches of artefacts, as it will require a lot of computation time and processing capacity. Likewise, it could be difficult to generate accurate 3D models of very small and/or detailed tool shapes using 3D surface scanners because stone tools are often much smaller than the recommended minimum field of view. Similarly, the resolution of conventional medical CT scanners might not be sufficient to capture minor details of stone tools, such as the outline or dorsal scars. Thus, high-resolution micro-CT technology is the only reliable way to accurately capture the overall morphology of small stone tools. This protocol aims at providing the first detailed procedure dedicated to the scanning of small lithic implements for further three-dimensional analysis. Note that some of the steps must be repeated at different working stages throughout this protocol. In cases where a task must be done in the exact same way as described in a previous step, a reference to that step is provided. When slight changes were made, the step was modified and reported entirely. This protocol contains a few red and green colours (e.g., arrows or within-program colours) which might be perceived differently by people with dyschromatopsia. However, the display of these colours has been kept to a minimum. We recommend the reader to go over the entire protocol carefully, even if only some specific parts are required. A few points are in fact interdependent, and some of them must be applied simultaneously. Content: Part 1 – Styrofoam preparation Part 2 – Micro-CT scanning Part 3 – 3D model extraction of CT scanned stone artifacts using Avizo Part 4 – Cropping extracted surface model to separate Face A and B in Artec Studio Part 5 – Cropping Face A to separate the lines in Artec Studio Part 6 – Cropping each stone artefact from the lines in Artec Studio Part 7 – Virtually control measurements in MeshLab Part 8 – Artec scanning of larger artifacts Part 9 – Export meshes as non-binary ply models for successive analysis in geomorph Three-dimensional example (in ply format) of the effectivity of the StyroStone Protocol: You can download an example of one Styrofoam line in 3D obtained using our protocol to appreciate the result that can be achieved. We have selected a line where objects are characterized by different metric and morphological attributes. Notice the retouching well visible in the last five smaller artifacts (counting from the left when artifact are oriented with the dorsal face in front of the observer and the butt down), as well as the platforms and bulbs of all artifacts. For more information and examples, feel free to contact us!

Download Full-text

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

JOM ◽

10.1007/s11837-014-0884-4 ◽

2014 ◽

Vol 66 (4) ◽

pp. 559-565 ◽

Cited By ~ 1

Author(s):

T. Winkler ◽

X. Y. Dai ◽

G. Mielke ◽

S. Vogt ◽

H. Buechner ◽

...

Keyword(s):

Computed Tomography ◽

Calcium Salt ◽

Three Dimensional ◽

Micro Ct ◽

Micro Computed Tomography

Download Full-text

Dual-energy micro-CT of the rodent lung

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00359.2011 ◽

2012 ◽

Vol 302 (10) ◽

pp. L1088-L1097 ◽

Cited By ~ 33

Author(s):

C. T. Badea ◽

X. Guo ◽

D. Clark ◽

S. M. Johnston ◽

C. D. Marshall ◽

...

Keyword(s):

Contrast Agent ◽

Vascular Tissue ◽

Ex Vivo ◽

Respiratory Gating ◽

Three Dimensional ◽

Dual Energy ◽

Volume Estimation ◽

Micro Ct ◽

Micro Computed Tomography

The purpose of this work is to investigate the use of dual-energy micro-computed tomography (CT) for the estimation of vascular, tissue, and air fractions in rodent lungs using a postreconstruction three material decomposition method. Using simulations, we have estimated the accuracy limits of the decomposition for realistic micro-CT noise levels. Next, we performed experiments involving ex vivo lung imaging in which intact rat lungs were carefully removed from the thorax, injected with an iodine-based contrast agent, and then inflated with different volumes of air ( n = 2). Finally, we performed in vivo imaging studies in C57BL/6 mice ( n = 5) using fast prospective respiratory gating in end inspiration and end expiration for three different levels of positive end expiratory pressure (PEEP). Before imaging, mice were injected with a liposomal blood pool contrast agent. The three-dimensional air, tissue, and blood fraction maps were computed and analyzed. The results indicate that separation and volume estimation of the three material components of the lungs are possible. The mean accuracy values for air, blood, and tissue were 93, 93, and 90%, respectively. The absolute accuracy in determining all fraction materials was 91.6%. The coefficient of variation was small (2.5%) indicating good repeatability. The minimum difference that we could detect in material fractions was 15%. As expected, an increase in PEEP levels for the living mouse resulted in statistically significant increases in air fractions at end expiration but no significant changes at end inspiration. Our method has applicability in preclinical pulmonary studies where changes in lung structure and gas volume as a result of lung injury, environmental exposures, or drug bioactivity would have important physiological implications.

Download Full-text

New artery of knowledge: 3D models of angiogenesis

Vascular Biology ◽

10.1530/vb-19-0026 ◽

2019 ◽

Vol 1 (1) ◽

pp. H135-H143

Author(s):

Eleonora Zucchelli ◽

Qasim A Majid ◽

Gabor Foldes

Keyword(s):

Network Formation ◽

Ex Vivo ◽

Imaging Techniques ◽

Three Dimensional ◽

3D Models ◽

Complex Processes ◽

Organ Repair ◽

Three Dimensional Models

Angiogenesis and vasculogenesis are complex processes by which new blood vessels are formed and expanded. They play a pivotal role not only in physiological development and growth and tissue and organ repair, but also in a range of pathological conditions, from tumour formation to chronic inflammation and atherosclerosis. Understanding the multistep cell-differentiation programmes and identifying the key molecular players of physiological angiogenesis/vasculogenesis are critical to tackle pathological mechanisms. While many questions are yet to be answered, increasingly sophisticated in vitro, in vivo and ex vivo models of angiogenesis/vasculogenesis, together with cutting-edge imaging techniques, allowed for recent major advances in the field. This review aims to summarise the three-dimensional models available to study vascular network formation and to discuss advantages and limitations of the current systems.

Download Full-text

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.

Download Full-text

A Micro-Computed Tomography Comparison of the Porosity in Additively Fabricated CuCr1 Alloy Parts Using Virgin and Surface-Modified Powders

Materials ◽

10.3390/ma14081995 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1995

Author(s):

Mirko Sinico ◽

Suraj Dinkar Jadhav ◽

Ann Witvrouw ◽

Kim Vanmeensel ◽

Wim Dewulf

Keyword(s):

High Energy ◽

High Energy Density ◽

Micro Ct ◽

Micro Computed Tomography ◽

Powder Bed ◽

Metallurgical Defects ◽

Ct Analysis ◽

Ct Data ◽

Surface Modified ◽

Fusion Pores

Recently, the use of novel CuCr1 surface-modified powder for reliable laser powder-bed fusion (LPBF) manufacturing has been proposed, enabling a broader LPBF processing window and longer powder storage life. Nevertheless, virgin CuCr1 powder is also LPBF processable, on the condition that a high-energy density is employed. In this work, we compare two dense specimens produced from virgin and surface-modified CuCr1 powder. Furthermore, a third sample fabricated from surface-modified powder is characterized to understand an abnormal porosity content initially detected through Archimedes testing. Utilizing high-resolution micro-CT scans, the nature of the defects present in the different samples is revealed. Pores are analyzed in terms of size, morphology and spatial distribution. The micro-CT data reveal that the virgin CuCr1 dense specimen displays keyhole pores plus pit cavities spanning multiple layer thicknesses. On the other hand, the sample fabricated with the surface-modified CuCr1 powder mainly contains small and spherical equi-distributed metallurgical defects. Finally, the CT analysis of the third specimen reveals the presence of a W contamination, favoring lack-of-fusion pores between subsequent LPBF layers. The LPBF melting mode (keyhole or conductive), the properties of the material, and the potential presence of contaminants are connected to the different porosity types and discussed.

Download Full-text

Prevascularized, Co-Culture Model for Breast Cancer Drug Development

ASME 2012 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2012-80409 ◽

2012 ◽

Author(s):

Lauren Marshall ◽

Isabel Löwstedt ◽

Paul Gatenholm ◽

Joel Berry

Keyword(s):

Breast Cancer ◽

Drug Development ◽

Three Dimensional ◽

Human Tumor ◽

3D Models ◽

Cancer Drug ◽

Cancer Therapies ◽

Anti Cancer

The objective of this study was to create 3D engineered tissue models to accelerate identification of safe and efficacious breast cancer drug therapies. It is expected that this platform will dramatically reduce the time and costs associated with development and regulatory approval of anti-cancer therapies, currently a multi-billion dollar endeavor [1]. Existing two-dimensional (2D) in vitro and in vivo animal studies required for identification of effective cancer therapies account for much of the high costs of anti-cancer medications and health insurance premiums borne by patients, many of whom cannot afford it. An emerging paradigm in pharmaceutical drug development is the use of three-dimensional (3D) cell/biomaterial models that will accurately screen novel therapeutic compounds, repurpose existing compounds and terminate ineffective ones. In particular, identification of effective chemotherapies for breast cancer are anticipated to occur more quickly in 3D in vitro models than 2D in vitro environments and in vivo animal models, neither of which accurately mimic natural human tumor environments [2]. Moreover, these 3D models can be multi-cellular and designed with extracellular matrix (ECM) function and mechanical properties similar to that of natural in vivo cancer environments [3].

Download Full-text

The Role of Pre-Clinical 3-Dimensional Models of Osteosarcoma

International Journal of Molecular Sciences ◽

10.3390/ijms21155499 ◽

2020 ◽

Vol 21 (15) ◽

pp. 5499

Author(s):

Hannah L. Smith ◽

Stephen A. Beers ◽

Juliet C. Gray ◽

Janos M. Kanczler

Keyword(s):

Three Dimensional ◽

Chorioallantoic Membrane ◽

3D Models ◽

In Ovo ◽

Future Directions ◽

3 Dimensional ◽

In Vivo Animal Models

Treatment for osteosarcoma (OS) has been largely unchanged for several decades, with typical therapies being a mixture of chemotherapy and surgery. Although therapeutic targets and products against cancer are being continually developed, only a limited number have proved therapeutically active in OS. Thus, the understanding of the OS microenvironment and its interactions are becoming more important in developing new therapies. Three-dimensional (3D) models are important tools in increasing our understanding of complex mechanisms and interactions, such as in OS. In this review, in vivo animal models, in vitro 3D models and in ovo chorioallantoic membrane (CAM) models, are evaluated and discussed as to their contribution in understanding the progressive nature of OS, and cancer research. We aim to provide insight and prospective future directions into the potential translation of 3D models in OS.

Download Full-text