Surface Roughness on the Slots and Wings of Various Ceramic Self-Ligating Brackets and their Potential Concern on Biofilm Formation

2020 ◽  
Vol 44 (6) ◽  
pp. 451-458
Author(s):  
Ki-Ho Park ◽  
Se Jik Han ◽  
Samjin Choi ◽  
Kyung Sook Kim ◽  
Steven Park ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Chemical Composition ◽  
Biofilm Formation ◽  
Control Group ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Significant Difference ◽  
Orthodontic Materials

Objective: The surface roughness of various orthodontic materials could affect biofilm formation and friction. The purpose of this study was to examine the surface roughness and chemical composition of the slots and wings of several ceramic self-ligating brackets. Study design: Four types of ceramic self-ligating brackets were separated into experimental groups (DC, EC, IC, and QK) while a metal self-ligating bracket (EM) was used as the control group. Atomic force microscopy and energy-dispersive x-ray spectroscope were used to examine the surface roughness and chemical composition of each bracket slot and wing. Results: The control group was made of ferrum and chrome while all the experimental groups were comprised of aluminum and oxide. There was a statistically significant difference in the roughness average (Sa) among the various self-ligating brackets (p< 0.001 in slots and p<0.01 in the wing). The slots in the EC group had the lowest Sa, followed by the DC, IC, control, and QK groups. The wings in the IC group had the lowest Sa, followed by the EC, DC, control, and QK groups. Conclusions: There is a significant difference in the surface roughness of the slots and wings among several types of ceramic self-ligating brackets.

scholarly journals Comparison of the Enamel Surface Roughness from Different Polishing Methods: Scanning Electron Microscopy and Atomic Force Microscopy Investigation

2020 ◽  
Vol 14 (02) ◽  
pp. 299-305
Author(s):  
Kiatanan Sugsompian ◽  
Ratchawan Tansalarak ◽  
Thosapol Piyapattamin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Enamel Surface ◽  
Similar Data ◽  
Force Microscopy ◽  
Atomic Force ◽  
Significant Difference ◽  
Scanning Electron

Abstract Objective This study aimed to compare the enamel surface roughness created by four polishing methods after debonding, by using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Materials and Methods Four experimental polishing groups (Sof-Lex disc, SD; sandblaster, SB; tungsten carbide bur, TB; and white stone bur, WB) and one control group were selected from 100 premolars (n = 20/group). The experimental teeth were bonded with a bracket, thermocycled, and debonded. Residual adhesive was removed by either of the respective methods. Pre and postdebonding root mean square (Rq) values were obtained from AFM evaluations. All specimens were examined and evaluated with SEM using a modified enamel surface index (modified ESI). Statistical Analysis Differences among the polishing methods were compared with analysis of variance and Fisher’s least significant difference test at p < 0.05. Results Both microscopic evaluations indicated that the surface with the greatest roughness herein belonged to the SD group, followed by that for SB, TB, and WB groups. AFM measurements indicated a maximum postdebonding Rq herein for the WB group and a significantly greater surface roughness for the TB and WB groups than for the SD and SB groups. Among the experimental groups, SEM followed by modified ESI evaluations revealed similar data to those obtained with AFM. Significant differences were seen among all paired groups, except for that between the SB and TB groups. Conclusion Within the limitations of this study, all four polishing methods were concluded to be clinically acceptable for removing residual orthodontic adhesives.

The surface roughness investigation by the atomic force microscopy, x-ray scattering, and light scattering

2006 ◽  
Author(s):  
M. L. Zanaveskin ◽  
Yu. V. Grishchenko ◽  
A. L. Tolstikhina ◽  
V. E. Asadchikov ◽  
B. S. Roshchin ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Light Scattering ◽  
X Ray ◽  
Force Microscopy ◽  
X Ray Scattering ◽  
Atomic Force ◽  
Ray Scattering

scholarly journals Effect of Hydrofluoric Acid Surface Treatments on Surface Roughness and Three-Point Flexural Strength of Suprinity Ceramic

2020 ◽  
Author(s):  
Nazanin Keshmiri ◽  
Homayoon Alaghehmand ◽  
Faraneh Mokhtarpour
Keyword(s):  
Surface Roughness ◽  
Flexural Strength ◽  
Hydrofluoric Acid ◽  
Testing Machine ◽  
Etching Time ◽  
Control Group ◽  
Force Microscopy ◽  
Atomic Force ◽  
Significant Difference ◽  
Before And After

Objectives: This study aimed to evaluate the effects of hydrofluoric acid (HF) concentration and etching time on the surface roughness (SR) and three-point flexural strength of Suprinity and to analyze the surface elements before and after etching. Materials and Methods: To measure the SR, 70 specimens of Suprinity (2×4×5mm3) were assigned to seven groups (n=10). Six groups were etched for 20, 60, and 120 seconds with 5% and 10% HF and 7th group was the control group. Specimens were evaluated using atomic force microscopy (AFM). One specimen from each group was used to analyze the surface elements using scanning electron microscopy (SEM). For measuring the three-point flexural strength, 60 specimens were divided into six groups (n=10) and etched as previously described. The flexural strength was measured using a universal testing machine. T-test, one-way analysis of variance (ANOVA), and two-way ANOVA were used for statistical analyses (P<0.05). Results: The 10% concentration of HF caused higher SR compared to the 5% HF. The effect of HF concentration on the flexural strength was significantly different in the 20- and 60-second etching groups. Different etching times had no significantly different effect on the SR. With 5% HF, the flexural strength was significantly higher for 20-second etching time than for the etching times of 60 and 120 seconds. With 10% HF, there was a significant difference in flexural strength between etching times of 20 and 120 seconds. The atomic percentage (at%) of silica was enhanced by increasing the etching time. Conclusions: The best surface etching protocol comprises 10% HF used for 20 seconds.

Influence of Thermal Annealing on the Properties of Sputtered Si Rich Silicon Oxide Films

2010 ◽  
Vol 159 ◽  
pp. 101-104
Author(s):  
Emil Manolov ◽  
Mario Curiel ◽  
Nicola Nedev ◽  
Diana Nesheva ◽  
Juan Terrazas ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Refractive Index ◽  
Photoelectron Spectroscopy ◽  
Silicon Oxide ◽  
High Temperature Annealing ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Variable Angle Spectroscopic Ellipsometry

Thin SiOx films deposited by reactive r.f. magnetron sputtering of Si at partial pressure ratios R between oxygen and argon in the range 15%-0.03% are studied. X-ray photoelectron spectroscopy and Variable angle spectroscopic ellipsometry prove enrichment with Si of the layers deposited at R < 0.5 %. Ellipsometric data give information about the refractive index and extinction coefficient of the films. Atomic Force Microscopy results show that for all samples high temperature annealing at 1000oC leads to a decrease of the surface roughness.

Surface Morphology of InxGa1-xAs/GaAs Relaxed Layers Characterized by Atomic Force Microscopy

1994 ◽  
Vol 340 ◽  
Author(s):  
G. Padeletti ◽  
G. M. Ingo ◽  
P. Imperatori
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Strain Relaxation ◽  
Grazing Incidence ◽  
Dislocation Network ◽  
X Ray Diffraction ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Combined Use

ABSTRACTGa0.65In0.35As layers of a varying nominal epilayer thickness (10 – 1000 nm) have been grown by the MBE technique on GaAs (100) substrates and characterized by the combined use of atomic force microscopy (AFM) and grazing incidence X-ray diffraction (GIXD). The surface roughness and morphology have been investigated. The GIXD and AFM results show that the thinnest films are characterized by an asymmetric strain relaxation along the two <110> directions with no surface crosshatched pattern but with a misfit dislocation network. AFM images on the thickest films show also well-oriented protrusions along the [110] direction, which increase in size and become more elongated as the nominal film thickness increases.

scholarly journals Surface Modification of Polyethersulfone (PES) with UV Photo-Oxidation

Technologies ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 36
Author(s):  
Ibrahim Cisse ◽  
Sarah Oakes ◽  
Shreen Sachdev ◽  
Marc Toro ◽  
Shin Lutondo ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Atomic Force Microscopy ◽  
Photoelectron Spectroscopy ◽  
Water Contact ◽  
X Ray ◽  
Force Microscopy ◽  
Photo Oxidation ◽  
Atomic Force ◽  
Modified Surfaces

Polyethersulfone (PES) films are widely employed in the construction of membranes where there is a desire to make the surface more hydrophilic. Therefore, UV photo-oxidation was studied in order to oxidize the surface of PES and increase hydrophilicity. UV photo-oxidation using low pressure mercury lamps emitting both 253.7 and 184.9 nm radiation were compared with only 253.7 nm photons. The modified surfaces were characterized using X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and water contact angle (WCA) measurements. Both sets of lamps gave similar results, showing an increase of the oxygen concentration up to a saturation level of ca. 29 at.% and a decrease in the WCA, i.e., an increase in hydrophilicity, down to ca. 40°. XPS detected a decrease of sp2 C-C aromatic group bonding and an increase in the formation of C-O, C=O, O=C-O, O=C-OH, O-(C=O)-O, and sulphonate and sulphate moieties. Since little change in surface roughness was observed by AFM, the oxidation of the surface caused the increase in hydrophilicity.

scholarly journals Influence of cycling profile, depth of discharge and temperature on commercial LFP/C cell ageing: post-mortem material analysis of structure, morphology and chemical composition

2020 ◽  
Vol 50 (11) ◽  
pp. 1101-1117
Author(s):  
M. Simolka ◽  
J. -F. Heger ◽  
H. Kaess ◽  
I. Biswas ◽  
K. A. Friedrich
Keyword(s):  
Atomic Force Microscopy ◽  
Chemical Composition ◽  
Photoelectron Spectroscopy ◽  
Temperature Cycling ◽  
Anode Surface ◽  
Post Mortem ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Micrometer Size

Abstract The paper presents post-mortem analysis of commercial LiFePO4 battery cells, which are aged at 55 °C and − 20 °C using dynamic current profiles and different depth of discharges (DOD). Post-mortem analysis focuses on the structure of the electrodes using atomic force microscopy (AFM) and scanning electron microscopy (SEM) and the chemical composition changes using energy dispersive X-ray spectroscopy (SEM-EDX) and X-ray photoelectron spectroscopy (XPS). The results show that ageing at lower DOD results in higher capacity fading compared to higher DOD cycling. The anode surface aged at 55 °C forms a dense cover on the graphite flakes, while at the anode surface aged at − 20 °C lithium plating and LiF crystals are observed. As expected, Fe dissolution from the cathode and deposition on the anode are observed for the ageing performed at 55 °C, while Fe dissolution and deposition are not observed at − 20 °C. Using atomic force microscopy (AFM), the surface conductivity is examined, which shows only minor degradation for the cathodes aged at − 20 °C. The cathodes aged at 55 °C exhibit micrometer size agglomerates of nanometer particles on the cathode surface. The results indicate that cycling at higher SOC ranges is more detrimental and low temperature cycling mainly affects the anode by the formation of plated Li. Graphic abstract

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