Effect of Two Vital Bleaching Agents on the Color Properties of the Low-Fusing Dental Ceramics

Dental ceramics have an excellent ability to reproduce natural teeth appearance, but once the substrate has an altered coloration, it is necessary to mask this intercurrence, considering the characteristics of the ceramic and cement selected. This article aims to present a clinical case of rehabilitation with ceramic laminates to mask a darkened central incisor by planning a more opaque porcelain structure under a translucent contact lens. A female patient sought dental care complaining of dissatisfaction with smile aesthetics. It was clinically identified the presence of a Class IV darkened restoration in composite resin in element 11. In treatment planning harmony in the shape and color of elements 11 and 21 was aimed at through lithium disilicate lenses. An opaque intermediate structure was used to cover the darkening in tooth 11. The double molding technique was performed to obtain the working model. Prior to cementing, the surfaces were treated. In ceramics, conditioning with 10% hydrofluoric acid and 37% phosphoric acid, silane application and universal adhesive; in dental substrate, conditioning with 37% phosphoric acid and application of universal adhesive were performed. In laminates definitive cementation Allcem Venner cement was chosen. Patient reported satisfaction with treatment final aesthetics. Thus, cementation technique of a translucent laminate over an opaque facet is a good option for masking substrates with darkened coloration.

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Clarification Processes of Orange Prickly Pear Juice (Opuntia spp.) by Microfiltration

Membranes ◽

10.3390/membranes11050354 ◽

2021 ◽

Vol 11 (5) ◽

pp. 354

Author(s):

Jaime A. Arboleda Mejia ◽

Jorge Yáñez-Fernandez

Keyword(s):

Suspended Solids ◽

Cross Flow ◽

Laboratory Scale ◽

Prickly Pear ◽

Permeate Flux ◽

Color Properties ◽

Pear Juice ◽

Opuntia Spp

In this study, fresh orange prickly pear juice (Opuntia spp.) was clarified by a cross-flow microfiltration (MF) process on a laboratory scale. The viability of the process—in terms of productivity (permeate flux of 77.80 L/h) and the rejection of selected membranes towards specific compounds—was analyzed. The quality of the clarified juice was also analyzed for total antioxidants (TEAC), betalains content (mg/100 g wet base), turbidity (NTU) and colorimetry parameters (L, a*, b*, Croma and H). The MF process permitted an excellent level of clarification, reducing the suspended solids and turbidity of the fresh juice. In the clarified juice, a decrease in total antioxidants (2.03 TEAC) and betalains content (4.54 mg/100 g wet basis) was observed as compared to the fresh juice. Furthermore, there were significant changes in color properties due to the effects of the L, a*, b*, C and h° values after removal of turbidity of the juice. The turbidity also decreased (from 164.33 to 0.37 NTU).

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The effects of thickness and shade on translucency parameters of contemporary, esthetic dental ceramics

Journal of Esthetic and Restorative Dentistry ◽

10.1111/jerd.12733 ◽

2021 ◽

Author(s):

Ioana Sofia Pop‐Ciutrila ◽

Razvan Ghinea ◽

Diana Dudea ◽

Javier Ruiz‐López ◽

Maria M. Pérez ◽

...

Keyword(s):

Dental Ceramics

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Hydrothermal Ageing and Its Effect on Fracture Load of Zirconia Dental Implants

Materials ◽

10.3390/ma14113103 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3103

Author(s):

Laurent Gremillard ◽

Agnès Mattlet ◽

Alexandre Mathevon ◽

Damien Fabrègue ◽

Bruno Zberg ◽

...

Keyword(s):

Dental Implants ◽

Fracture Load ◽

Accelerated Ageing ◽

Dental Ceramics ◽

X Ray Diffraction ◽

X Ray ◽

Dental Restorations ◽

Different Temperatures ◽

Mechanical Performances ◽

Kinetics Of

Due to growing demand for metal-free dental restorations, dental ceramics, especially dental zirconia, represent an increasing share of the dental implants market. They may offer mechanical performances of the same range as titanium ones. However, their use is still restricted by a lack of confidence in their durability and, in particular, in their ability to resist hydrothermal ageing. In the present study, the ageing kinetics of commercial zirconia dental implants are characterized by X-ray diffraction after accelerated ageing in an autoclave at different temperatures, enabling their extrapolation to body temperature. Measurements of the fracture loads show no effect of hydrothermal ageing even after ageing treatments simulated a 90-year implantation.

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Optical Characterization of Alternaria spp. Contaminated Wheat Grain and Its Influence in Early Broilers Nutrition on Oxidative Stress

Sustainability ◽

10.3390/su13074005 ◽

2021 ◽

Vol 13 (7) ◽

pp. 4005

Author(s):

Nikola Puvača ◽

Snežana Tanasković ◽

Vojislava Bursić ◽

Aleksandra Petrović ◽

Jordan Merkuri ◽

...

Keyword(s):

Oxidative Stress ◽

Body Weight ◽

Broiler Chickens ◽

Basal Diet ◽

Feed Consumption ◽

Control Treatment ◽

Second Phase ◽

Wheat Grain ◽

Color Properties ◽

Dietary Treatments

The aim of this research was the visual characterization and investigating the effects of Alternaria spp. contaminated wheat grains in the starter stage of broilers nutrition on productive parameters and oxidative stress. The research was divided into two phases. Bunches of wheat in post-harvest period of year 2020 was collected from a various locality in Serbia and Albania. In the first phase, collected samples were visual characterized by Alternaria spp. presence by color measurement methods. Gained results are conferred in the range of the color properties of grain color properties of Alternaria toxins. Wheat grain samples were significantly different (p < 0.05) in terms of all measured color parameters (L*, a*, b*). Classification of field fungi in analyzed wheat grain samples showed that the significant field fungi were Rhizopus spp., followed by Alternaria spp., and Fusarium spp. In the second phase, biological tests with chickens were carried out during the broiler chickens’ dietary starter period in the first 14th days of age. At the beginning of the experiment, a total of 180-day-old Ross 308 strain broilers were equally distributed into three dietary treatments, with four replicates each. Dietary treatments in the experiments were as follows: basal diet without visual contamination of Alternaria spp. with 25% wheat (A1), a basal diet with visual contamination of Alternaria spp. with 25% wheat from Serbia (A2), basal diet with visual contamination of Alternaria spp. with 25% wheat from Albania (A3). The trial with chickens lasted for 14 days. After the first experimental week, wheat infected with Alternaria spp. in treatment A2 and A3 expressed adverse effects. The highest body weight of chickens of 140.40 g was recorded in broilers on control treatment A1 with statistically significant differences (p < 0.05) compared to treatments A2 (137.32 g) and A3 (135.35 g). At the end of the second week of test period, a statistically significant (p < 0.05) difference in body weight of broiler chickens could be noticed. The highest body weight of 352.68 g was recorded in control treatment A1, with statistically significant differences compared to other Alternaria spp. treatments. The lowest body weight of chickens was recorded in treatment A3 (335.93 g). Results of feed consumption and feed conversion ratio showed some numerical differences between treatments but without any statistically significant differences (p > 0.05). Alternaria spp. contaminated diet increased glutathione (GSH), glutathione reductase (GR), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) and decreased peroxidase (POD) and superoxide dismutase (SOD) serum levels, respectively. Built on the achieved results, it can be concluded that the wheat contaminated with Alternaria spp. in broilers nutrition negatively affected growth, decreased oxidative protection and interrupted chicken welfare in the first period of life.

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