Structure, properties and in-vitro response of SiO2-Na2O-CaO-P2O5 system based glass-ceramics after partial replacement of Na2O by Li2O

The study in vitro of the glass powders bioactivity was performed by soaking them in simulated body fluid for 3 to 21 days at a temperature of 37�C and pH = 7.20. The synthesis de novo of hydroxyapatite, post soaking was confirmed by Fourier Transform Infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The study of the antimicrobial activity was performed by microbiological examination on two strains of pathogenic bacteria involved in postoperative nosocomial infections.

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Factors Affecting the Wear Behavior of Monolithic Zirconia and the Antagonists: Literature Review

Current Dentistry ◽

10.2174/2542579x02666200206111259 ◽

2020 ◽

Vol 2 (1) ◽

pp. 4-11

Author(s):

Marcia Borba ◽

Paula Benetti ◽

Giordana P. Furini ◽

Kátia R. Weber ◽

Tábata M. da Silva

Keyword(s):

Literature Review ◽

Glass Ceramic ◽

Wear Behavior ◽

Glass Ceramics ◽

Surface Treatments ◽

Human Tooth ◽

Initial Surface ◽

Monolithic Zirconia ◽

Feldspathic Porcelain

Background: The use of zirconia-based ceramics to produce monolithic restorations has increased due to improvements in the optical properties of the materials. Traditionally, zirconiabased ceramics were veneered with porcelain or glass-ceramic and were not directly exposed to the oral environment. Therefore, there are several doubts regarding the wear of the monolithic zirconia restoration and their antagonists. Additionally, different surface treatments are recommended to promote a smooth surface, including glaze and several polishing protocols. To support the correct clinical application, it is important to understand the advantages and limitations of each surface treatment. Objective: The aim of this short literature review is to investigate the factors that may affect the wear of monolithic zirconia restorations in service and their antagonists. Methods: Pubmed/Medline database was accessed to review the literature from a 10-year period using the keywords: zirconia, monolithic, prosthesis, wear. Both clinical and in vitro studies were included in the review. Results: Studies investigated the effect of several surface treatments, including grinding with diamond- burs, polishing and glazing, on the surface roughness, phase transformation and wear capacity of monolithic zirconia. The wear behavior of monolithic zirconia was frequently compared to the wear behavior of other ceramics, such as feldspathic porcelain, lithium disilicate-based glassceramic and leucite-reinforced glass-ceramic. Human tooth, ceramics and resin composites were used as antagonist in the investigations. Only short-term clinical studies are available (up to 2 years). Conclusion: Literature findings suggest that zirconia monolithic restorations are wear resistant and unlikely to cause excessive wear to the antagonist, especially when compared to feldspathic porcelain and glass-ceramics. Monolithic zirconia should be polished rather than glazed. Yet, none of the polishing systems studied was able to completely restore the initial surface conditions of zirconia after being adjusted with burs. More clinical evidence of the antagonist tooth wear potential of monolithic zirconia is needed.

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Microstructure and surface texture driven improvement in in-vitro response of laser surface processed AZ31B magnesium alloy

Journal of Magnesium and Alloys ◽

10.1016/j.jma.2020.11.002 ◽

2021 ◽

Author(s):

Tso-Chang Wu ◽

Sameehan S. Joshi ◽

Yee-Hsien Ho ◽

Mangesh V. Pantawane ◽

Subhasis Sinha ◽

...

Keyword(s):

Magnesium Alloy ◽

Surface Texture ◽

Laser Surface ◽

Az31b Magnesium Alloy ◽

In Vitro Response

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Loss of Nitric Oxide Induces Fibrogenic Response in Organotypic 3D Co-Culture of Mammary Epithelia and Fibroblasts—An Indicator for Breast Carcinogenesis

Cancers ◽

10.3390/cancers13112815 ◽

2021 ◽

Vol 13 (11) ◽

pp. 2815

Author(s):

Gang Ren ◽

Xunzhen Zheng ◽

Vandana Sharma ◽

Joshua Letson ◽

Andrea L. Nestor-Kalinoski ◽

...

Keyword(s):

Nitric Oxide ◽

Culture System ◽

Epithelial Mesenchymal Transition ◽

Precancerous Lesions ◽

Three Dimensional ◽

Epidemiological Studies ◽

Mesenchymal Transition ◽

In Vitro Response ◽

Mammary Epithelia

Excessive myofibroblast activation, which leads to dysregulated collagen deposition and the stiffening of the extracellular matrix (ECM), plays pivotal roles in cancer initiation and progression. Cumulative evidence attests to the cancer-causing effects of a number of fibrogenic factors found in the environment, diseases and drugs. While identifying such factors largely depends on epidemiological studies, it would be of great importance to develop a robust in vitro method to demonstrate the causal relationship between fibrosis and cancer. Here, we tested whether our recently developed organotypic three-dimensional (3D) co-culture would be suitable for that purpose. This co-culture system utilizes the discontinuous ECM to separately culture mammary epithelia and fibroblasts in the discrete matrices to model the complexity of the mammary gland. We observed that pharmaceutical deprivation of nitric oxide (NO) in 3D co-cultures induced myofibroblast differentiation of the stroma as well as the occurrence of epithelial–mesenchymal transition (EMT) of the parenchyma. Such in vitro response to NO deprivation was unique to co-cultures and closely mimicked the phenotype of NO-depleted mammary glands exhibiting stromal desmoplasia and precancerous lesions undergoing EMT. These results suggest that this novel 3D co-culture system could be utilized in the deep mechanistic studies of the linkage between fibrosis and cancer.

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