scholarly journals In vitro analysis of dental ceramics: evaluation of the radiopacity and chemical composition by raman spectroscopy

2018 ◽  
Vol 21 (2) ◽  
pp. 164
Author(s):  
Rodrigo Furtado De Carvalho ◽  
Fernando Luiz Goulart Cruz ◽  
Debora Pinto Antunes ◽  
Evane Gonçalves Toledo Júnior ◽  
Luiz Fernando Cappa De Oliveira ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Chemical Composition ◽  
Analysis Of Variance ◽  
Dental Ceramics ◽  
Restorative Dentistry ◽  
Digital Radiographs ◽  
Vitro Analysis ◽  
Post Hoc ◽  
In Vitro Analysis

<p><strong>Objective</strong>: This study compared the radiopacity of different ceramic systems by means of digital radiographs and evaluate the chemical composition of the samples by Raman spectroscopy. <strong>Material and Methods</strong>: The hypothesis tested was that there was a difference in radiopacity among the tested materials. Specimens were prepared for each ceramic tested: FLD - VM7 (VITA Zahnfabrik), LD - IPS Empress e.max Press (IPS Empress), AL - In Ceram Alumina (VITA Zahnfabrik), ALYZ - In Ceram Zirconia (VITA Zahnfabrik), YZ - Lava All Ceram (3M/ESPE), and MYZ - Zirconzahn (Talladium Brazil). The specimens were radiographed and submitted to radiographic density readings using a histogram tool. The spectrometer coupled to a petrographic microscope was used for Raman spectroscopy measurements. Analysis of variance (ANOVA) and a Tukey post-hoc test were used to compare radiopacity of the different materials. <strong>Results</strong>: For all tested materials, the radiopacity showed statistically significant differences, except YZ and MYZ. Lava All Ceram and ZirkonZahn had high radiopacity values and VM7 and IPS Empress e.max Press showed lower radiopacity than human dental structures. <strong>Conclusion</strong>: It was possible to conclude that radiopacity is closely linked to ceramic chemical composition.</p><p><strong>Keywords</strong></p><p>Dental ceramics; Radiopacity; Raman spectroscopy test; Restorative dentistry.</p>

scholarly journals In-vitro analysis of maxillary first molars morphology using three dimensional Micro-CT imaging: considerations for restorative dentistry

2019 ◽  
pp. 75-81 ◽  
Author(s):  
Ismail Hakki Baltacioglu ◽  
◽  
Gulbike Demirel ◽  
Mehmet Eray Kolsuz ◽  
Kaan Orhan ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Ct Imaging ◽  
Micro Ct ◽  
Restorative Dentistry ◽  
Vitro Analysis ◽  
In Vitro Analysis

102 Raman spectroscopy: In-vitro analysis of urinary stone composition at different excitation wavelengths

2012 ◽  
Vol 11 (1) ◽  
pp. e102-e102a
Author(s):  
A. Miernik ◽  
K. Wilhelm ◽  
C. Bolwien ◽  
Y. Eilers ◽  
A. Lambrecht ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Urinary Stone ◽  
Stone Composition ◽  
Vitro Analysis ◽  
In Vitro Analysis

scholarly journals An in vitro analysis of the total phenolic content, antioxidant power, physical, physicochemical, and chemical composition of Terminalia Catappa Linn fruits

2012 ◽  
Vol 32 (1) ◽  
pp. 209-213 ◽  
Author(s):  
Marcelo Rodrigues Marques ◽  
Diego Damasceno Paz ◽  
Lívia Patrícia Rodrigues Batista ◽  
Celma de Oliveira Barbosa ◽  
Marcos Antônio Mota Araújo ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Soluble Solids ◽  
Total Phenolic ◽  
Average Weight ◽  
Antioxidant Power ◽  
Terminalia Catappa ◽  
Solids Content ◽  
Vitro Analysis ◽  
In Vitro Analysis

This study assessed the antioxidant, total phenolic, and physicochemical properties of in vitro Terminalia Catappa Linn (locally called castanhola) using the DPPH assay. The castanhola fruits had an average weight of 19.60 ± 0.00 g, combining shell, pulp, and seed weight, and a soluble solids content of 8 °Brix. The chemical composition was determined with predominance of carbohydrates (76,88 ± 0,58%).The titration method was used to determine Vitamin C content using 2,6-dichlorophenolindophenol (DCFI), known as reactive Tillmans resulting in no significant levels. Aqueous extracts of castanhola pulp showed a higher concentration of phenolics, 244.33 ± 18.86 GAE.g-1 of fruit, and alcoholic extracts, 142.84 ± 2.09 GAE.g-1 of fruit. EC50 values of the aqueous extract showed a greater ability to scavenge free radicals than the alcoholic extracts. The fruit had a significant content of phenolic compounds and high antioxidant capacity.

scholarly journals Variations in the Shades of Contemporary Dental Ceramics: An In Vitro Analysis

Crystals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1288
Author(s):  
Syed Rashid Habib ◽  
Abdulaziz Saud Al Rashoud ◽  
Turki Ali Safhi ◽  
Abdulrahman Hamad Almajed ◽  
Hamad Ali Alnafisah ◽  
...  
Keyword(s):  
Statistical Tests ◽  
Color Difference ◽  
Ceramic Materials ◽  
Dental Ceramics ◽  
Color Differences ◽  
Monolithic Zirconia ◽  
Vitro Analysis ◽  
Post Hoc ◽  
Shade Guide

Background: To identify and compare the shade variations of various commonly used esthetic dental ceramics by calculating their total-color-difference (ΔE) and translucency parameter (TP) using a spectrophotometer. Methods: In total, 165 disc specimens from three shades (A1, B1, and C1) of five ceramic materials (N = 55/shade; n = 11/ceramic material group) were prepared (Metal-ceramic (MC), IPS e.max press (Emax-P), IPS e.max layer (Emax-L), Layered Zirconia (Zr-L) and Monolithic zirconia (Zr-M)). With a spectrophotometer, the L*a*b* values were obtained. Total color differences (ΔE = [(ΔL*)2 + (Δa*)2 + (Δb*)2]1/2) and translucency parameter (TP = [(L*B − L*W)2 + (a*B − a*W)2 + (b*B – b*W)2]1/2) were calculated. The statistical tests included ANOVA and Post hoc Tukey’s analysis (p < 0.05). Results: Significant differences (p = 0.000) were found between the groups for ΔE. Highest ΔE (A1) were found for Zr-L (80.18 ± 20) and lowest for Zr-M (62.97 ± 1.28). For B1, highest ΔE values were noted for MC (76.85 + 0.78) and lowest for the Emax-L (62.13 ± 1.49). For C1, highest ΔE values were found for the MC group (73.96 ± 0 67) and lowest for Emax-P (55.09 ± 1.76). Translucency variations between tested ceramics were revealed (p < 0.05). Highest TP values (A1) were found for Emax-L (2.99 ± 1.64) and lowest for Zr-L (0.35 ± 0.16). For B1, highest TP values were noted for Emax-P (3.50 ± 1.74) and lowest for MC (0.57 ± 0.40). For C1, highest TP values were found for Emax-P (4.46 ± 2.42) and lowest for MC (0.58 ± 0 48). Conclusions: Significant differences in ΔE and TP were found for tested ceramic groups. The color differences of the tested materials varied according to clinical acceptability, even with the selection of same color/shade. The color/shades of the various dental ceramics do not match with the vita shade guide tabs, to which they are compared most often. Shade differences are present between different lots of ceramic materials from the same or different brands.

The native structure of the eukaryotic ribosome

1983 ◽  
Vol 41 ◽  
pp. 432-433
Author(s):  
R.A. Milligan ◽  
P.N.T. Unwin
Keyword(s):  
Ribosomal Proteins ◽  
Crystal Form ◽  
Native Structure ◽  
X Ray Diffraction ◽  
Eukaryotic Ribosome ◽  
Vitro Analysis ◽  
In Vitro Analysis ◽  
Resolution Structure ◽  
Stable Unit

A detailed understanding of the mechanism of protein synthesis will ultimately depend on knowledge of the native structure of the ribosome. Towards this end we have investigated the low resolution structure of the eukaryotic ribosome embedded in frozen buffer, making use of a system in which the ribosomes crystallize naturally.The ribosomes in the cells of early chicken embryos form crystalline arrays when the embryos are cooled at 4°C. We have developed methods to isolate the stable unit of these arrays, the ribosome tetramer, and have determined conditions for the growth of two-dimensional crystals in vitro, Analysis of the proteins in the crystals by 2-D gel electrophoresis demonstrates the presence of all ribosomal proteins normally found in polysomes. There are in addition, four proteins which may facilitate crystallization. The crystals are built from two oppositely facing P4 layers and the predominant crystal form, accounting for >80% of the crystals, has the tetragonal space group P4212, X-ray diffraction of crystal pellets demonstrates that crystalline order extends to ~ 60Å.

1163: Radial Dilation of Ureteral Balloons: A Comparative in-Vitro Analysis

2005 ◽  
Vol 173 (4S) ◽  
pp. 315-316
Author(s):  
Kari Hendlin ◽  
Brynn Lund ◽  
Manoj Monga
Keyword(s):  
Vitro Analysis ◽  
In Vitro Analysis
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