Evaluation of marginal and internal fit of ceramic and metallic crown copings using x-ray microtomography (micro-CT) technology

Purpose. The aim of the study was to measure the marginal and internal adaptation (MIA) of zirconia copings, made of 4 ceramic systems for CAD/CAM, using microcomputed tomography (micro-CT) technology. Material and Methods. Two identical stainless steel models were used, representing a preparation for full ceramic crown on a lower molar. The master models were then scanned for the production of copings from specific yttrium oxide partially stabilized tetragonal zirconia polycrystal ceramic blocks of each system (n=10): Cerec/inCoris Zi, Sirona; Cercon/Cercon base, Dentsply; Ceramill/Ceramill Zi, Amann Girrbach; and Lava/Lava Frame Zirconia, 3M ESPE. MIA was evaluated measuring 4 points as follows: marginal gap (MG), axial wall gap (AW), axio-occlusal angle gap (AO), and central occlusal area gap (CO). The data were statistically analyzed by ANOVA and Tukey’s test (α = 0.05). Results. The ceramic system Lava showed greater internal desadaptation (80.75 ± 22.69 µm) while CEREC presented the lowest values (49.92 ± 11.77 µm). There were significant differences between the measurement points evaluated. CO demonstrated the greater values (77.03 ± 22.61 µm). All marginal and internal adaptation values were considered clinically acceptable. Conclusion. It was concluded that there was an influence of the type of ceramic system in marginal and internal adaptation of copings in zirconia.

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In situ dynamic X-ray micro-CT for additive manufactured parts

Microscopy and Microanalysis ◽

10.1017/s1431927621010266 ◽

2021 ◽

Vol 27 (S1) ◽

pp. 2944-2945

Author(s):

Jan Dewanckele ◽

Frederik Coppens ◽

Wesley De Boever ◽

Marijn Boone ◽

Luke Hunter

Keyword(s):

Micro Ct ◽

X Ray

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Simple low dose radiography allows precise lung volume assessment in mice

Scientific Reports ◽

10.1038/s41598-021-83319-5 ◽

2021 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Amara Khan ◽

Andrea Markus ◽

Thomas Rittmann ◽

Jonas Albers ◽

Frauke Alves ◽

...

Keyword(s):

Lung Function ◽

Whole Body ◽

Acquisition Time ◽

Micro Ct ◽

Lung Volumes ◽

X Ray ◽

Promising Tool ◽

Volume Assessment ◽

Set Up ◽

Time Required

AbstractX-ray based lung function (XLF) as a planar method uses dramatically less X-ray dose than computed tomography (CT) but so far lacked the ability to relate its parameters to pulmonary air volume. The purpose of this study was to calibrate the functional constituents of XLF that are biomedically decipherable and directly comparable to that of micro-CT and whole-body plethysmography (WBP). Here, we developed a unique set-up for simultaneous assessment of lung function and volume using XLF, micro-CT and WBP on healthy mice. Our results reveal a strong correlation of lung volumes obtained from radiographic XLF and micro-CT and demonstrate that XLF is superior to WBP in sensitivity and precision to assess lung volumes. Importantly, XLF measurement uses only a fraction of the radiation dose and acquisition time required for CT. Therefore, the redefined XLF approach is a promising tool for preclinical longitudinal studies with a substantial potential of clinical translation.

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