Streptococcus mutans Growth and Resultant Material Surface Roughness on Modified Glass Ionomers

SUMMARY The purpose of this study was to investigate the effects of surface roughness of resin composite on biofilm formation of Streptococcus mutans in the presence of saliva. To provide uniform surface roughness on composites, disks were prepared by curing composite against 400-grit silicon carbide paper (SR400), 800-grit silicon carbide paper (SR800), or a glass slide (SRGlass). The surface roughness was examined using confocal laser microscopy. For biofilm formation, S. mutans was grown for 24 hours with each disk in a biofilm medium with either glucose or sucrose in the presence of fluid-phase or surface-adsorbed saliva. The adherent bacteria were quantified via enumeration of the total viable counts of bacteria. Biofilms were examined using scanning electron microscopy. This study showed that SR400 had deeper and larger, but fewer depressions than SR800. Compared to SRGlass and SR800, biofilm formation was significantly increased on SR400. In addition, the differences in the effect of surface roughness on the amount of biofilm formation were not significantly influenced by either the presence of saliva or the carbohydrate source. Considering that similar differences in surface roughness were observed between SR400 and SR800 and between SR800 and SRGlass, this study suggests that surface topography (size and depth of depressions) may play a more important role than surface roughness in biofilm formation of S. mutans.

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The Effect of Various Surface Treatments of Ti6Al4V on the Growth and Osteogenic Differentiation of Adipose Tissue-Derived Stem Cells

Coatings ◽

10.3390/coatings10080762 ◽

2020 ◽

Vol 10 (8) ◽

pp. 762

Author(s):

Jana Stepanovska ◽

Roman Matejka ◽

Martin Otahal ◽

Jozef Rosina ◽

Lucie Bacakova

Keyword(s):

Stem Cells ◽

Surface Roughness ◽

Adipose Tissue ◽

Osteogenic Differentiation ◽

Water Drop ◽

Chemical Properties ◽

Surface Modifications ◽

Cell Number ◽

Material Surface ◽

Mitochondrial Activity

The physical and chemical properties of the material surface, especially its roughness and wettability, have a crucial effect on the adhesion, proliferation, and differentiation of cells. The aim of this study is to select the most appropriate surface modifications of Ti6Al4V implants for pre-colonization of the implants with adipose tissue-derived stem cells (ASCs) in order to improve their osseointegration. We compared the adhesion, growth, and osteogenic differentiation of rat ASCs on Ti6Al4V samples modified by methods commonly used for preparing clinically used titanium-based implants, namely polishing (PL), coating with diamond-like carbon (DLC), brushing (BR), anodizing (AND), and blasting (BL). The material surface roughness, measured by the Ra and Rq parameters, increased in the following order: PL < DLC ˂ BR ˂ AND ˂ BL. The water drop contact angle was in the range of 60–74°, with the exception of the DLC-coated samples, where it was only 38°. The cell number, morphology, mitochondrial activity, relative fluorescence intensity of osteogenic markers RUNX2, type 1 collagen, and osteopontin, the calcium consumption by the cells and the alkaline phosphatase activity depended on the surface roughness rather than on the surface wettability of the materials. Materials with a surface roughness of several tens of nanometers (Ra 60–70 nm), i.e., the BR and AND samples, supported a satisfactory level of cell proliferation. At the same time, they achieved the highest level of osteogenic cell differentiation. These surface modifications therefore seem to be most suitable for pre-colonization of Ti6Al4V implants with stem cells pre-differentiated toward osteoblasts, and then for implanting them into the bone tissue.

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Laser Surface Texturing and Electropolishing of CoCr and Ti6Al4V-ELI Alloys for Biomedical Applications

Materials ◽

10.3390/ma13225203 ◽

2020 ◽

Vol 13 (22) ◽

pp. 5203

Author(s):

Jesús A. Sandoval-Robles ◽

Ciro A. Rodríguez ◽

Erika García-López

Keyword(s):

Surface Roughness ◽

Unit Length ◽

Surface Texturing ◽

Orthopedic Implants ◽

Laser Surface Texturing ◽

Material Surface ◽

Roughness Parameters ◽

X Ray ◽

Surface Roughness Parameters ◽

Materials Used

The interplay between a prosthetic and tissue represents an important factor for the fixation of orthopedic implants. Laser texturing tests and electropolishing were performed on two materials used in the fabrication of medical devices, i.e., CoCr and Ti6Al4V-ELI alloys. The material surface was textured with a diode-pumped solid state (DPSS) laser and its effect on the surface quality and material modification, under different combinations of laser power and marking speed, were investigated. Our results indicate that an increment of energy per unit length causes an incremental trend in surface roughness parameters. Additionally, phase transformation on the surface of both alloys was achieved. Chemical analysis by energy dispersive X-ray spectrometer (EDX) shows the formation of (Co(Cr,Mo)) phase and the M23C6 precipitate on the CoCr surface; while quantitative analysis of the X-ray diffractometer (XRD) results demonstrates the oxidation of the Ti alloy with the formation of Ti2O and Ti6O from the reduction of the α-Ti phase. The behaviors were both related with an increase of the energy per unit length. Control of the final surface roughness was achieved by an electropolishing post-treatment, minimizing the as-treated values. After polishing, a reduction of surface roughness parameters was obtained in a range between 3% and 44%, while no changes in chemical composition or present phases were observed.

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Impact of Structural Defects on the Surface Quality of Hardwood Species Sliced Veneers

Applied Sciences ◽

10.3390/app10186265 ◽

2020 ◽

Vol 10 (18) ◽

pp. 6265

Author(s):

Vasiliki Kamperidou ◽

Efstratios Aidinidis ◽

Ioannis Barboutis

Keyword(s):

Surface Roughness ◽

Surface Quality ◽

Wood Species ◽

Research Work ◽

Structural Defects ◽

Material Surface ◽

Typical Structure ◽

Hardwood Species ◽

The Impact

The surface roughness constitutes one of the most critical properties of wood and wood veneers for their extended utilization, affecting the bonding ability of the veneers with one another in the manufacturing of wood composites, the finishing, coating and preservation processes, and the appearance and texture of the material surface. In this research work, logs of five significant European hardwood species (oak, chestnut, ash, poplar, cherry) of Balkan origin were sliced into decorative veneers. Their surface roughness was examined by applying a stylus tracing method, on typical wood structure areas of each wood species, as well as around the areas of wood defects (knots, decay, annual rings irregularities, etc.), to compare them and assess the impact of the defects on the surface quality of veneers. The chestnut veneers presented the smoothest surfaces, while ash veneers, despite the higher density, recorded the highest roughness. In most of the cases, the roughness was found to be significantly lower around the defects, compared to the typical structure surfaces, probably due to lower porosity, higher density and the presence of tensile wood. The results reveal that the presence of defects does not affect the roughness of the veneers and increases neither the processing requirements of the veneer sheets before finishing, nor the respective production cost of veneers and the veneer-based wood panels. The high utilization prospects of the examined wood species in veneer production, even those bearing various defects, is highlighted.

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Yarn and fabric properties in a modified ring spinning system considering the effect of the friction surface of the false-twister

Textile Research Journal ◽

10.1177/0040517519873057 ◽

2019 ◽

Vol 90 (5-6) ◽

pp. 572-580 ◽

Cited By ~ 2

Author(s):

Rong Yin ◽

Xiao-Ming Tao ◽

Bin-gang Xu

Keyword(s):

Surface Roughness ◽

Friction Surface ◽

Experimental Results ◽

Material Surface ◽

Ring Spinning ◽

Knitted Fabrics ◽

Yarn Properties ◽

Cotton Yarns ◽

The Relationship

This paper experimentally studies the relationship between the friction surface of a false-twisting unit and the quality of cotton yarns produced by a modified ring spinning system, with the adoption of the single friction-belt false-twister. The friction surface of the false-twisting unit, as a key twisting component, has been studied in terms of material, surface roughness, hardness and diameter, as well as the interaction between these factors and resultant yarn properties, with particular attention to yarn imperfections. Experimental results showed that the false-twisting unit with a short interactive path demonstrated significant reduction of yarn imperfections, especially yarn neps. With the optimal false-twisting unit, performances of the modified yarns and their knitted fabrics were evaluated and compared with the conventional ones.

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Biomechanical evaluation between orthodontic attachment and three different materials after various surface treatments: A three-dimensional optical profilometry analysis

The Angle Orthodontist ◽

10.2319/072918-547.1 ◽

2019 ◽

Vol 89 (5) ◽

pp. 742-750

Author(s):

İrem Kurt ◽

Zafer Cavit Çehreli ◽

Ayça Arman Özçırpıcı ◽

Çağla Şar

Keyword(s):

Surface Roughness ◽

Three Dimensional ◽

Material Surface ◽

Original Material ◽

Average Surface Roughness ◽

Average Surface ◽

Diamond Bur ◽

Monolithic Zirconia ◽

Feldspathic Porcelain ◽

The Impact

ABSTRACT Objectives: To determine the best bonding method of orthodontic attachment among monolithic zirconia, feldspathic porcelain, hybrid porcelain, and the impact of surface-conditioning methods using a three-dimensional optical profilometer after debonding. Materials and Methods: 56 feldspathic porcelain, 56 monolithic zirconia, and 56 hybrid porcelain samples were divided into four surface treatment subgroups: (1) hydrofluoric (HF) acid etch + silane, (2) Al2O3 sandblasting + silane, (3) silicoating (SiO2), and (4) diamond bur + silane. The specimens were tested to evaluate shear bond strength (SBS). Residual composite was removed after debonding. Three-dimensional white-light interferometry was used to obtain quantitative measurements on surface roughness. Results: The highest SBS value was found for the HF acid–etched feldspathic porcelain group. The average surface roughness values were significantly higher in all material groups in which diamond bur was applied, while roughening with Cojet provided average surface roughness values closer to the original material surface. Conclusions: Variations in structures of the materials and roughening techniques affected the SBS and surface roughness findings.

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The Study of Surface Roughness and MRR of Mild Steel Using Manual Plasma Arc Cutting Machining

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.576.3 ◽

2012 ◽

Vol 576 ◽

pp. 3-6 ◽

Cited By ~ 1

Author(s):

R. Bhuvenesh ◽

M.S. Abdul Manan ◽

M.H. Norizaman

Keyword(s):

Surface Roughness ◽

Removal Rate ◽

Cutting Process ◽

Material Surface ◽

Plasma Arc ◽

Manufacturing Companies ◽

Average Roughness ◽

Plasma Arc Cutting ◽

Before And After ◽

Manual Plasma

Manufacturing companies define the qualities of thermal removing process based on the dimension and physical appearance of the cutting material surface. Therefore, the roughness of the surface area of the cutting material and the rate of the material being removed during the manual plasma arc cutting process was importantly considered. Plasma arc cutter Selco Genesis 90 was used to cut the specimens made from Standard AISI 1017 Steel manually based on the selected parameters setting. Two different thicknesses of specimens with 3mm and 6mm were used. The material removal rate (MRR) was measured by determining the weight of the specimens before and after the cutting process. The surface roughness (SR) analysis was conducted to determine the average roughness (Ra) value. Taguchi method was utilized as an experimental layout to obtain MRR and Ra values. The results reveal that for the case of manual plasma arc cutting machining, the SR values are inversely proportional to the MRR values. The quality of the surface roughness depends on the dross peak that occurred during the cutting process.

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Surface Electrical Resistances Properties of CNF/PC Nano-Composite Processing by Injection Molding

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.339.367 ◽

2011 ◽

Vol 339 ◽

pp. 367-370 ◽

Cited By ~ 2

Author(s):

Jian Hui Qiu ◽

Kengo Uchiya ◽

Lei Lin ◽

Xue Li Wu ◽

Yang Zhao

Keyword(s):

Surface Roughness ◽

Injection Molding ◽

Electrical Resistance ◽

Surface Resistance ◽

Carbon Nanofiber ◽

High Surface ◽

Material Surface ◽

Nano Composite ◽

Injection Speed ◽

Surface Electrical Resistance

In the present work, carbon nanofibers (CNF) were dispersed into polycarbonate (PP) with an injection molding machine. The effect of the injection conditions on the electrical resistance of carbon nanofiber/polycarbonate (CNF/PC) nanocomposites was investigated. It was found that the surface resistance decreased with the increase of injection speed and injection temperature. The surface electrical resistance was affected by the particle size and dispersion of CNF, the effect of depth on surface resistance of the composites was studied, the surface electrical resistance sharply increased from the material surface to the internal at first, after that, a decreased slowly was observed. The effect of surface roughness on surface electrical resistance was also studied, the composite with a low surface resistance was greatly influenced when surface roughness changed, while there was not a same phenomenon when the composites have a high surface resistance.

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Study on Polishing Technology for Hard-Brittle Materials by a Micro Abrasive Water Jet

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1027.52 ◽

2014 ◽

Vol 1027 ◽

pp. 52-57 ◽

Cited By ~ 1

Author(s):

Zeng Wen Liu ◽

R.Y. Liu

Keyword(s):

Surface Roughness ◽

Surface Quality ◽

Silicate Glass ◽

Material Removal ◽

Brittle Materials ◽

Material Surface ◽

Abrasive Water Jet ◽

Removal Mechanism ◽

Material Removal Mechanism ◽

Average Roughness

s: Abrasive jet micromachining is considered as a promising precision processing technology for brittle materials such as silicate glass and silicon nitride that are increasingly used in various applications. In this study, some polishing experiments are conducted for hard-brittle materials by a micro slurry jet. The results show that the morphology and the integrity of the material surface are improved greatly after polishing. The average roughness (Ra) value of the silicate glass decrease from 2.32μm to 0.35μm and the average roughness (Ra) value of the Si3N4 decrease from 2.63μm to 0.34μm. The material removal mechanism and the surface formation mechanism are studied. The factors to influence the surface morphology, the surface quality and the surface roughness are analyzed in order to take measures to improve the surface quality and reduce the surface roughness value.

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Analisis Fabrikasi Desain Passive Mixing Microchannel Perangkat Mikrofluidik Material Acrylic Dengan Laser CO2 Daya Rendah

JTT (Jurnal Teknologi Terapan) ◽

10.31884/jtt.v2i2.20 ◽

2017 ◽

Vol 2 (2) ◽

Author(s):

Badruzzaman Badruzzaman ◽

Ario Sunar Baskoro

Keyword(s):

Surface Roughness ◽

Cutting Tools ◽

Cutting Speed ◽

Fluid Mixing ◽

Material Surface ◽

Passive Mixing ◽

Process Channel ◽

Flow Through ◽

Bonding Method ◽

Tissue Fluids

Microfluidics devices have been applied in the biomedical field to manipulate the tissue fluids in channels with dimensions between 5-500 lm. Microfluidics device manufactured by a microfabrication process consisting of design, microstucturing and back-end processes. One application of microfluidics is a passive mixing microchannel. In this device, the liquid will flow through the channel without any moving parts and the pressure from the outside to produce a fluid mixing. It is important to design the shape of the channel to generate a nice passive mixing microchannel. Low power CO2 laser is used to process microstucturing as cutting tools to produce microfluidic devices on acyilic material. Surface roughness lines were designed to be observed. In this study, the design process channel carried by the experimental method through the parameters that affect the output of the process is the power of laser cutting, cutting speed and design channel. And then the fabrication of microfluidics with back-end processing is done by the process of merging with a thermal bonding method. Finally, From the experimental results, the design of the channel 1 has an influence on all the parameters for surface roughness compared with a channel design 2.

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