Surface Properties of Dental Nanocomposites After Finishing WithRigid Rotary Instruments

2013 ◽  
Vol 38 (5) ◽  
pp. 519-527 ◽  
Author(s):  
SM Marchan ◽  
D White ◽  
QM Marchan ◽  
V Dhuru ◽  
WA Smith
Keyword(s):  
Surface Roughness ◽  
Surface Characteristics ◽  
Qualitative Assessment ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Control Groups ◽  
Average Roughness ◽  
Rotary Instruments ◽  
Finished Surface ◽  
Post Hoc

SUMMARY This study evaluated the surface characteristics of three nanoparticle resin composites (Z350, Heritage 7 Nanohybrid, and Ice) using profilometry and scanning electronic microscopy (SEM) after subjecting them to sequential finishing procedures using rigid rotary instruments. Fifteen 8 mm × 8 mm × 2 mm specimens were fabricated for each tested composite and subjected to one of the following finishing regimens: finishing with green stones followed by white stones, finishing with 45-μm diamond followed by 15-μm diamond, finishing with a 12-fluted carbide followed by a 20-fluted carbide. After finishing, the surfaces were subjected to profilometric testing. Eight parallel tracings were used to scan the finished surface of each specimen. For each recorded profile, the average roughness (Ra) and extreme value descriptor (Rmax) were recorded. On completion of the profilometric testing, two specimens from each group were randomly selected for qualitative assessment by SEM. Profilometric data was analyzed using a one-way analysis of variance and post hoc Scheffe tests. The results demonstrated that the three control groups of the tested nanocomposites behaved as a coherent group with respect to surface roughness. With the exception of the nanohybrid Heritage 7 finished with the carbide instruments, all composites showed an increase in surface roughness. The Z350 and Ice finished with the carbide finishing instruments showed no statistically significant increase in Ra, but both of these composites showed significantly rougher surfaces when finished with diamonds compared with controls. The nanohybrids Ice and Heritage 7 demonstrated significantly higher roughness in terms of Rmax when finished with stones. The SEM correlated well with roughness measurements. The conclusion may be drawn that diamonds and stones produce unacceptable surfaces in terms of roughness on the tested nanocomposites whereas finishing carbides produce acceptable surfaces.

Influence of Temperature on Characteristics of TiAl Plasma Surface Niobiumizing

2007 ◽  
Vol 353-358 ◽  
pp. 1854-1857 ◽  
Author(s):  
Xiao Ping Liu ◽  
Wen Huai Tian ◽  
Chao Li Guo ◽  
Dong Dong Chen ◽  
Zhi Yong He ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Energy Dispersive Spectrum ◽  
Alloyed Layer ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Influence Of Temperature ◽  
Plasma Surface ◽  
Influence Of Temperature On ◽  
Discharge Spectrum ◽  
Source Electrode

In this study, plasma niobium alloying of the TiAl based alloys has been carried out at 1050, 1100 and 1150°C. The effect of the alloying temperature on the characteristic of the alloyed layer was investigated by optical microscopy, scanning electronic microscopy (SEM), glow discharge spectrum (GDS) and energy dispersive spectrum (EDS). The results show that the surface roughness, chemical composition and thickness of the alloyed layer increased with the alloying temperature which is dependent on the sheath potential. A deposition layer formed on the TiAl surface at 1150 °C was resulted from the larger sheath potential or the stronger sputtering of source electrode.

Magnetorheological finishing of copper cylindrical roller for its improved performance in printing machine

2020 ◽  
pp. 095440892094523
Author(s):  
Manpreet Singh ◽  
Anant Kumar Singh
Keyword(s):  
Surface Roughness ◽  
Surface Hardness ◽  
Ground Surface ◽  
Surface Characteristics ◽  
Fluid Composition ◽  
Finishing Process ◽  
Finished Surface ◽  
Measuring Machine ◽  
Mr Polishing Fluid ◽  
Cylindrical Roller

The copper cylindrical roller plays an important role in the printing operation. The copper roller requires fine and uniform finishing to uniformly distribute the colours and ingot material. Fine and uniform finishing of copper cylindrical rollers get difficulty using the traditional finishing processes due to their ductility and low hardness. Therefore, to achieve this fine finishing requirement, the rotary rectangular tool core-based magnetorheological (MR) finishing process is employed. Initially, the suitable MR polishing fluid composition is selected for the effective fine finishing of the surface of the copper cylindrical rollers. Furthermore, the central composite design is used to optimize the MR finishing process parameters. The surface roughness profiles, surface texture, and reflection tests are performed on the initial ground surface and the MR finished surface of the copper roller. The surface roughness value gets reduced from 190 nm to 25 nm after 4 hrs MR finishing with the optimum parametric conditions over the copper cylindrical roller surface having a dimension of 120 mm in length and 25 mm in diameter. The present MR finishing process found effective to significantly reduce the surface roughness value and enhance the surface characteristics of the copper cylindrical rollers. The geometrical dimensions in terms of circularity and straightness are also checked on the initial ground surface and finished surface of the copper cylindrical roller using the coordinate measuring machine and waviness test. The enhancement in surface characteristics, dimensional accuracy, and surface hardness after the present MR finishing process is found to be beneficial for improving the functional performance of the copper cylindrical rollers in the printing processing machine.

scholarly journals Evaluation of the basic surface roughness of an ISO-certified and non-ISO-certified slot bracket with an atomic force microscope

2019 ◽  
Vol 31 (2) ◽  
pp. 91
Author(s):  
Chrisni Oktavia Jusup ◽  
Eky Setiawan Soeria Soemantri ◽  
Endah Mardiati ◽  
Ida Ayu Evangelina
Keyword(s):  
Surface Roughness ◽  
Stainless Steel ◽  
Atomic Force Microscope ◽  
Tooth Movement ◽  
Average Roughness ◽  
Base Surface ◽  
Atomic Force ◽  
Significant Difference ◽  
The Right ◽  
Post Hoc

Introduction: The base surface roughness of slot bracket can affect friction in tooth movement. There are ISO-certified and non-ISO-certified stainless steel brackets on the market. Thus orthodontists must be careful in choosing the right bracket. This study was aimed to evaluate the differences of the surface roughness of ISO-certified and non-ISO-certified Roth 0.022 inch stainless steel bracket with the parameter of S a (average roughness). Methods: This research was a laboratory observational. Samples were taken randomly as many as 32 brackets divided into two groups, each consisted of two bracket brands. Surface roughness measurements were performed using an atomic force microscope (AFM), then the data were analysed by ANOVA test (p < 0.05) and Post-Hoc analysis. Results: The ISO-certified bracket has an S a value smaller than the non-ISO-certified bracket. There was a significant difference in the surface roughness of the ISO-certified and non-ISO-certified slot bracket base (p < 0.05). Conclusion: The ISO-certified bracket has a smoother base surface than the non-ISO-certified bracket base.Keywords: Surface roughness, stainless steel slot bracket, atomic force microscope

scholarly journals Influence of Standard Load Micro- and Nanopatterned in Surface Roughness of bleached Teeth and submitted to Different Surface Treatments

2015 ◽  
Vol 16 (3) ◽  
pp. 167-171
Author(s):  
Mateus Rodrigues Tonetto ◽  
Mônica Barros Silva ◽  
André Afif Elossais ◽  
Matheus Coelho Bandeca ◽  
Shilpa H Bhandi ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Surface Texture ◽  
Artificial Saliva ◽  
Dental Enamel ◽  
Surface Treatments ◽  
Control Group ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Structural Alterations ◽  
Whitening Process

ABSTRACT The aim of this study was evaluate the dental enamel after whitening treatment with Opalescence Boost PF™ 38%, correlating the structural alterations in the surface of the enamel with its respective pH and verify if whitened teeth submitted to different finishing and polishing techniques show similar surface texture to healthy teeth (control group). Sixty premolars were divided in 6 groups (n = 10), which had been immersed in artificial saliva during all the experiment. Protocol whitening was performed according to the manufacturer recommendations, and then the specimens were submitted to different polishing technique with Sof-Lex Pop On™ disks, Flex Diamond™ felt disks using two different micrometric polishing pastes (Enamelize™ and Diamond Polish™) and two nanometric polishing pastes (Lummina-E Diamond and Lummina-E Alumina), according to the groups. Representative specimens were analyzed in scanning electronic microscopy (SEM). Whitening gel used in this experiment had modified the morphologic aspect of the enamel surface. It was found that two nanometric polishing pastes (G5 and G6) promoted a less rough surface compared to control group even after the whitening process. How to cite this article do Amaral Nacanichi R, Tonetto MR, Bandéca MC, Andrade MF, Segalla JCM, Silva MB, Bhandi SH, Pedro FLM, Elossais AA. Influence of Standard Load Microand Nanopatterned in Surface Roughness of bleached Teeth and submitted to Different Surface Treatments. J Contemp Dent Pract 2015;16(3):167-171.

scholarly journals Surface roughness in relation to altitude of hornbeam wood

2018 ◽  
Vol 24 (1) ◽  
Author(s):  
Majid Kiaei ◽  
Rasoul Mosavi Paloj
Keyword(s):  
Surface Roughness ◽  
Native Species ◽  
Roughness Parameter ◽  
Surface Characteristics ◽  
Peak Height ◽  
Solid Wood ◽  
Wood Products ◽  
Roughness Parameters ◽  
Average Roughness ◽  
Test Pieces

Hornbeam wood (Carpinus betulus) is a native species from Iran and covers 33% of the commercial volume of Iranian woods. Surface quality of solid wood products is one of the most important properties influencing further manufacturing processes such as finishing or strength of adhesive joint. Wood surface roughness is affected by growth condition. The objective of this study was to evaluate effect of altitude index (400 m, 800 m and 1200 m) on the surface roughness of sanded hornbeam wood (C. Betulus). Surface characteristics of sanded specimens of hornbeam wood were made employing a stylus profilmeter. Average roughness (Ra), mean peak-to-valley height (Rz), root-mean square deviation of the profile (Rq), core roughness depth (Rk), reduced peak height (Rpk), and reduced valley depth (Rvk) roughness parameters were used to determine surface characteristics of the test pieces. Significant statistical differences were found among altitude indexes in reduced valley depth parameter and wood oven-dried density, but not for the other variables. This variable did not have significantly effect on other surface roughness parameters in hornbeam wood. The low altitude had a rougher surface than intermediate and high altitudes. There is no relationship between surface roughness parameter and wood oven-dried density. 

scholarly journals Shaping and properties of thermoplastic scaffolds in tissue regeneration: The effect of thermal history on polymer crystallization, surface characteristics and cell fate

2021 ◽  
Author(s):  
Andrea Roberto Calore ◽  
Varun Srinivas ◽  
Shivesh Anand ◽  
Ane Albillos-Sanchez ◽  
Stan F. S. P. Looijmans ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Additive Manufacturing ◽  
Cell Fate ◽  
Thermal History ◽  
Cell Attachment ◽  
Surface Characteristics ◽  
Tissue Engineering Scaffolds ◽  
Average Roughness ◽  
Surface Stiffness ◽  
Crystallization Surface

Abstract Thermoplastic semi-crystalline polymers are excellent candidates for tissue engineering scaffolds thanks to facile processing and tunable properties, employed in melt-based additive manufacturing. Control of crystallization and ultimate crystallinity during processing affect properties like surface stiffness and roughness. These in turn influence cell attachment, proliferation and differentiation. Surface stiffness and roughness are intertwined via crystallinity, but never studied independently. The targeted stiffness range is besides difficult to realize for a single thermoplastic. Via correlation of thermal history, crystallization and ultimate crystallinity of vitamin E plasticized poly(lactide), surface stiffness and roughness are decoupled, disclosing a range of surface mechanics of biological interest. In osteogenic environment, human mesenchymal stromal cells were more responsive to surface roughness than to surface stiffness. Cells were particularly influenced by overall crystal size distribution, not by average roughness. Absence of mold-imposed boundary constrains makes additive manufacturing ideal to spatially control crystallization and henceforward surface roughness of semi-crystalline thermoplastics. Graphic abstract

scholarly journals Surface characteristics of particleboard produced from hydro-thermally treated wheat stalks

BioResources ◽  
2020 ◽  
Vol 15 (4) ◽  
pp. 7648-7659
Author(s):  
Ümit Büyüksarı ◽  
Hüseyin Akkılıç
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Digital Camera ◽  
Surface Characteristics ◽  
Thermal Modification ◽  
Scientific Instrument ◽  
Average Roughness ◽  
Wood Particles ◽  
Angle Method ◽  
Thermally Treated

Surface characteristics were studied for particleboards produced from hydro-thermally treated (HTT) and non-treated (NT) wheat stalk (WS). Wood and wheat stalk particles were used as experimental materials. The wheat stalk particles were subjected to HTT at a temperature of 180 °C for 8 minutes in a steam explosion machine. HTT and NT WS particles were added at 10%, 20%, 30%, and 40% to the wood particles. The surface roughness and wettability of the produced panels were determined. The roughness measurements, average roughness (Ra), maximum roughness (Rmax), and mean peak-to-valley height (Rz) were performed using a fine stylus tracing technique. The wetting behavior of the panels was characterized by the contact angle method (goniometer technique). The contact angle (CA) measurements were obtained by using a KSV Cam-101 Scientific Instrument connected with a digital camera and computer system. Statistical analyses showed significant differences in the surface roughness and wettability of the particleboards following hydro-thermal modification. The addition of WS to the panels significantly decreased the roughness values. However, all of the HTT groups exhibited higher roughness compared to NT groups. The CA values decreased when the WS content increased. The wettability of the particleboard containing HTT WS particles was improved.

scholarly journals Biofilm inhibition and bactericidal activity of NiTi alloy coated with graphene oxide/silver nanoparticles via electrophoretic deposition

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sirapat Pipattanachat ◽  
Jiaqian Qin ◽  
Dinesh Rokaya ◽  
Panida Thanyasrisung ◽  
Viritpon Srimaneepong
Keyword(s):  
Surface Roughness ◽  
Silver Nanoparticles ◽  
Graphene Oxide ◽  
Electrophoretic Deposition ◽  
Biofilm Formation ◽  
Niti Alloy ◽  
Surface Characteristics ◽  
Dependent Manner ◽  
Biofilm Inhibition ◽  
Coating Time

AbstractBiofilm formation on medical devices can induce complications. Graphene oxide/silver nanoparticles (GO/AgNPs) coated nickel-titanium (NiTi) alloy has been successfully produced. Therefore, the aim of this study was to determine the anti-bacterial and anti-biofilm effects of a GO/AgNPs coated NiTi alloy prepared by Electrophoretic deposition (EPD). GO/AgNPs were coated on NiTi alloy using various coating times. The surface characteristics of the coated NiTi alloy substrates were investigated and its anti-biofilm and anti-bacterial effect on Streptococcus mutans biofilm were determined by measuring the biofilm mass and the number of viable cells using a crystal violet assay and colony counting assay, respectively. The results showed that although the surface roughness increased in a coating time-dependent manner, there was no positive correlation between the surface roughness and the total biofilm mass. However, increased GO/AgNPs deposition produced by the increased coating time significantly reduced the number of viable bacteria in the biofilm (p < 0.05). Therefore, the GO/AgNPs on NiTi alloy have an antibacterial effect on the S. mutans biofilm. However, the increased surface roughness does not influence total biofilm mass formation (p = 0.993). Modifying the NiTi alloy surface using GO/AgNPs can be a promising coating to reduce the consequences of biofilm formation.

scholarly journals The Effects of Toothbrush Wear on the Surface Roughness and Gloss of Resin Composites with Various Types of Matrices

2021 ◽  
Vol 9 (1) ◽  
pp. 8
Author(s):  
Murtadha AlAli ◽  
Nikolaos Silikas ◽  
Julian Satterthwaite
Keyword(s):  
Surface Roughness ◽  
Pairwise Comparisons ◽  
Resin Composites ◽  
Hybrid Resin ◽  
Before And After ◽  
Post Hoc ◽  
Main Effects ◽  
Toothbrush Wear

Objective: To evaluate and compare the surface roughness and gloss of a DMA-free composite and Bis-GMA-free composite with a DMA-based composite before and after toothbrushing simulation. Materials and Methods: Fifteen dimensionally standardised composite specimens of three nano-hybrid resin composites (Tetric EvoCeram, Admira Fusion, and Venus Diamond) were used. Five specimens from each composite were polished and then subjected to a toothbrushing simulator. Surface roughness (Ra) and gloss were measured before toothbrushing and after 5000, 10,000, 15,000, and 20,000 toothbrushing cycles. The data was analysed using 5 × 3 ANOVA to assess surface roughness and gloss values and pairwise comparisons in the form of Tukey post hoc tests were performed to interpret main effects. Results: For all tested materials, surface roughness increased, and gloss decreased after toothbrushing abrasion. Surface roughness (Ra) values ranged from 0.14 to 0.22 μm at baseline and increased to between 0.41 and 0.49 μm after 20,000 toothbrushing cycles. Gloss values ranged between 31.9 and 50.6 GU at baseline and between 5.1 and 19.5 GU after 20,000 toothbrushing cycles. The lowest initial Ra value was detected in Venus Diamond and the highest initial gloss value was detected in Tetric EvoCeram. Conclusions: Simulated toothbrushing abrasion led to an increase in surface roughness and a decrease in gloss for all tested materials. Venus Diamond had the smoothest surface and Tetric EvoCeram had the glossiest surface after polishing and following 20,000 cycles of toothbrushing abrasion. Admira Fusion demonstrated the roughest surface and had the lowest gloss values before and after toothbrushing abrasion.

Modeling of surface roughness in a novel magnetorheological gear profile finishing process

2020 ◽  
pp. 095440622097826
Author(s):  
Ravi Datt Yadav ◽  
Anant Kumar Singh ◽  
Kunal Arora
Keyword(s):  
Surface Roughness ◽  
Gear Tooth ◽  
Surface Characteristics ◽  
Spur Gear ◽  
Tooth Profile ◽  
Tooth Surface ◽  
Magnetic Flux Density ◽  
Element Analysis ◽  
Finishing Process ◽  
Gear Profile

Fine finishing of spur gears reduces the vibrations and noise and upsurges the service life of two mating gears. A new magnetorheological gear profile finishing (MRGPF) process is utilized for the fine finishing of spur gear teeth profile surfaces. In the present study, the development of a theoretical mathematical model for the prediction of change in surface roughness during the MRGPF process is done. The present MRGPF is a controllable process with the magnitude of the magnetic field, therefore, the effect of magnetic flux density (MFD) on the gear tooth profile has been analyzed using an analytical approach. Theoretically calculated MFD is validated experimentally and with the finite element analysis. To understand the finishing process mechanism, the different forces acting on the gear surface has been investigated. For the validation of the present roughness model, three sets of finishing cycle experimentations have been performed on the spur gear profile by the MRGPF process. The surface roughness of the spur gear tooth surface after experimentation was measured using Mitutoyo SJ-400 surftest and is equated with the values of theoretically calculated surface roughness. The results show the close agreement which ranges from −7.69% to 2.85% for the same number of finishing cycles. To study the surface characteristics of the finished spur gear tooth profile surface, scanning electron microscopy is used. The present developed theoretical model for surface roughness during the MRGPF process predicts the finishing performance with cycle time, improvement in the surface quality, and functional application of the gears.

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