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.

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&lt; 0.001 in slots and p&lt;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 Effect of hydrofluoric acid etching duration on the roughness and flexural strength of a lithium disilicate-based glass ceramic

2011 ◽  
Vol 22 (1) ◽  
pp. 45-50 ◽  
Author(s):  
Lucas Villaça Zogheib ◽  
Alvaro Della Bona ◽  
Estevão Tomomitsu Kimpara ◽  
John F. Mccabe
Keyword(s):  
Surface Roughness ◽  
Flexural Strength ◽  
Glass Ceramic ◽  
Hydrofluoric Acid ◽  
Lithium Disilicate ◽  
Bending Test ◽  
Acid Etching ◽  
Etching Time ◽  
Control Group ◽  
The Mean

The aim of this study was to examine the effect of different acid etching times on the surface roughness and flexural strength of a lithium disilicate-based glass ceramic. Ceramic bar-shaped specimens (16 mm x 2 mm x 2 mm) were produced from ceramic blocks. All specimens were polished and sonically cleaned in distilled water. Specimens were randomly divided into 5 groups (n=15). Group A (control) no treatment. Groups B-E were etched with 4.9% hydrofluoric acid (HF) for 4 different etching periods: 20 s, 60 s, 90 s and 180 s, respectively. Etched surfaces were observed under scanning electron microscopy. Surface profilometry was used to examine the roughness of the etched ceramic surfaces, and the specimens were loaded to failure using a 3-point bending test to determine the flexural strength. Data were analyzed using one-way ANOVA and Tukey's test (?=0.05). All etching periods produced significantly rougher surfaces than the control group (p<0.05). Roughness values increased with the increase of the etching time. The mean flexural strength values were (MPa): A=417 ± 55; B=367 ± 68; C=363 ± 84; D=329 ± 70; and E=314 ± 62. HF etching significantly reduced the mean flexural strength as the etching time increased (p=0.003). In conclusion, the findings of this study showed that the increase of HF etching time affected the surface roughness and the flexural strength of a lithium disilicate-based glass ceramic, confirming the study hypothesis.

scholarly journals Effect of 0.05% Sodium Fluoride Mouthwash on Surface Roughness and Friction Between Ceramic Brackets and Rhodium-Coated and Uncoated Stainless Steel Wires

2019 ◽  
Author(s):  
Tahereh HosseinzadehNik ◽  
Hannaneh Ghadirian ◽  
Tabassom Hooshmand ◽  
Mohammad Javad Kharrazi fard ◽  
Maryam Nasiri ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Stainless Steel ◽  
Sodium Fluoride ◽  
Artificial Saliva ◽  
Testing Machine ◽  
Significance Level ◽  
Force Microscopy ◽  
Atomic Force ◽  
Before And After ◽  
Ceramic Brackets

Objectives: This study aimed to assess the effect of 0.05% sodium fluoride (NaF) mouthwash on the surface roughness and friction between ceramic brackets and rhodium-coated (RC) and uncoated stainless steel (SS) wires. Materials and Methods: This experimental study was performed on 48 maxillary premolar ceramic brackets. Twenty-four pieces of RC-SS wires were used. Samples were divided into four groups. Groups 1 and 2 were immersed in artificial saliva, and groups 3 and 4 were immersed in a solution consisting of artificial saliva (9%) and mouthwash (91%). To assess surface roughness, images were obtained from the surface of wires and brackets with atomic force microscopy (AFM) and scanning electron microscopy (SEM) before and after the intervention. To assess friction, the wires were ligated into brackets, and friction was measured at a crosshead speed of 0.5 mm/minute using a universal testing machine. Data were analyzed using one-way analysis of variance (ANOVA) at the 0.05 significance level. Results: Friction during sliding in RC wires was significantly less than that in SS wires (P<0.05). Increase in the friction in SS wires by mouthwash was significantly greater compared to RC wires (P<0.05). Surface roughness coefficients of the wires before the intervention were not significantly different. The surface roughness of the wires significantly increased after the intervention and it was greater in SS wires than in RC wires (P<0.05). Conclusion: Considering the lower friction and surface roughness of SS-RC wires compared to SS wires, SS-RC wires may be a better alternative for use with ceramic brackets.

scholarly journals The effect of denture cleanser 48% sodium bicarbonate on surface roughness changes of heat-cured acrylic resin

2021 ◽  
Vol 5 (1) ◽  
pp. 19-23
Author(s):  
Syahrial , ◽  
Pocut Aya Sofya ◽  
Adellya Tasya Sukma
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Sodium Bicarbonate ◽  
Acrylic Resin ◽  
Force Microscopy ◽  
Atomic Force ◽  
Liquid Absorption ◽  
Significant Difference ◽  
Before And After ◽  
Artificial Teeth

The surface of heat-cured acrylic resin on the base of artificial teeth has a risk of surface roughness. Its causes are liquid absorption and chemical processes. Fluid absorption can be affected by immersion in denture cleaners containing sodium bicarbonate. This study aims to determine the effect of a denture cleanser containing 48% sodium bicarbonate on changes in heat-cured acrylic resin's roughness. This study used 16 specimens of heat-cured acrylic resin (brand Meliodent) and was square in size of 10x10x2.0 ± 0.5 mm. The samples' roughness is measured by using Atomic Force Microscopy (AFM). The specimens were immersed in denture cleansing tablets containing 48% sodium bicarbonate for 17 days at room temperature ± 25 °C and were replaced within 8 hours. After immersion, the specimens were measured again using Atomic Force Microscopy (AFM) to determine the final roughness. The data obtained were analyzed by using paired t-test. The analysis showed no significant difference between surface roughness before and after soaking with a denture cleansing tablet containing 48% sodium bicarbonate (p 0.05). This study concluded that there was no increase in the roughness of heat-cured acrylic resin after immersion in denture cleansing tablets containing 48% sodium bicarbonateKEYWORDS: Fittydent, heat-cured acrylic resin, surface roughness

scholarly journals Effects of Different Polishing Procedures on the Surface Roughness and Hardness of Polyether Ether Ketone (PEEK)

2020 ◽  
pp. 219-227
Author(s):  
Alper Ozdogan ◽  
Büsra Tosun
Keyword(s):  
Surface Roughness ◽  
Vickers Hardness ◽  
Environmental Scanning Electron Microscopy ◽  
Environmental Scanning ◽  
Control Group ◽  
Force Microscopy ◽  
Atomic Force ◽  
Polyether Ether Ketone ◽  
Significant Difference ◽  
Ether Ketone

There is insufficient information about the chairside polishing methods of polyether ether ketone material. Therefore, it is aimed in this study to investigate the effects of different polishing processes on polyether ether ketone surface roughness and hardness. A total of 66 disc-shaped specimens made of polyether ether ketone were used in this study. The specimens were polished conventionally and randomly divided into three groups (n=22). One group was designated as the control group, and no further treatment was applied. In the other two groups, the specimens’ surfaces were abraded with diamond burs and polished using two different polishing kits. Their surface roughness and Vickers hardness were measured, and environmental scanning electron microscopy and atomic force microscopy examinations were performed. The data were statistically analysed using analysis of variance and Tukey’s honest significant difference test (α=0.05). There were no statistically significant differences between the control and polishing kit groups in terms of either surface roughness or Vickers hardness (p>0.05). The polishing kits can be used reliably and effectively for polishing polyether ether ketone materials.

scholarly journals Comparison of Interproximal Reduction Techniques and Proximal Strips: An Atomic Force Microscopic and Confocal Microscopic Study

2020 ◽  
Vol 54 (1) ◽  
pp. 44-48
Author(s):  
Pooja Harish S ◽  
Karunakara B C ◽  
Sumitra Reddy
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscope ◽  
High Speed ◽  
Reduction Technique ◽  
Tooth Surface ◽  
Control Group ◽  
Reduction Techniques ◽  
Atomic Force ◽  
Significant Difference ◽  
Before And After

Objective: A vivo study was conducted to evaluate the surface roughness produced by two different methods: hand-held mechanical and air-rotor stripping and also by HORICO and Ortho-Organizer strips (Bengaluru, India), before and after polishing with 3M Sof-Lex Finishing Strips under Atomic Force Microscope. Methodology: Study included 44 proximal surfaces of extracted premolars divided into a control group and 3 experimental groups with 12 surfaces in each. Hand-held mechanical stripping was done by 40 passages of 6 cm long abrasive strips and air-rotor stripping using high-speed air-rotor turbine hand piece. Polishing was done using 3M Sof-Lex finishing strips. Reduced teeth samples were viewed under Atomic Force Microscope and the proximal strips under Confocal microscope for surface roughness. Results: Air-rotor stripping produced statistically significant more surface roughness compared to the mechanical reduction technique ( P = .01). There was no significant difference between the roughnesses produced by 2 different proximal strips. Tooth surface after IPR with polishing had less roughness compared to unpolished surface. There was no mean difference between the wear of proximal strips. Conclusion: The mechanical reduction technique of interproximal surface produces less surface roughness compared to air-rotor stripping. Polishing with 3M Sof-Lex strips after reduction irrespective of the technique and material used gives smoother surface than even normal enamel.

Surface roughness measurements of vanadium-contaminated fluidized cracking catalysts by atomic force microscopy

1996 ◽  
Vol 54 ◽  
pp. 866-867
Author(s):  
H. Kinney ◽  
M.L. Occelli ◽  
S.A.C. Gould
Keyword(s):  
Surface Roughness ◽  
Zeolite Y ◽  
Atomic Level ◽  
Microporous Structure ◽  
Contact Mode ◽  
Force Microscopy ◽  
Atomic Force ◽  
Before And After ◽  
Roughness Measurements ◽  
Cracking Catalysts

For this study we have used a contact mode atomic force microscope (AFM) to study to topography of fluidized cracking catalysts (FCC), before and after contamination with 5% vanadium. We selected the AFM because of its ability to well characterize the surface roughness of materials down to the atomic level. It is believed that the cracking in the FCCs occurs mainly on the catalysts top 10-15 μm suggesting that the surface corrugation could play a key role in the FCCs microactivity properties. To test this hypothesis, we chose vanadium as a contaminate because this metal is capable of irreversibly destroying the FCC crystallinity as well as it microporous structure. In addition, we wanted to examine the extent to which steaming affects the vanadium contaminated FCC. Using the AFM, we measured the surface roughness of FCCs, before and after contamination and after steaming.We obtained our FCC (GRZ-1) from Davison. The FCC is generated so that it contains and estimated 35% rare earth exchaged zeolite Y, 50% kaolin and 15% binder.

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.

scholarly journals Effect of whitening dentifrices on the surface roughness of a nanohybrid composite resin

2016 ◽  
Vol 10 (02) ◽  
pp. 170-175 ◽  
Author(s):  
Gabriela Migliorin da Rosa ◽  
Luciana Mendonça da Silva ◽  
Márcio de Menezes ◽  
Hugo Felipe do Vale ◽  
Diego Ferreira Regalado ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Composite Resin ◽  
Wilcoxon Test ◽  
Control Group ◽  
Mean Values ◽  
Short Period ◽  
Significant Difference ◽  
Before And After ◽  
Nanohybrid Composite ◽  
One Way Anova

ABSTRACT Objectives: The present study verified the influence of whitening dentifrices on the surface roughness of a nanohybrid composite resin. Materials and Methods: Thirty-two specimens were prepared with Filtek™ Z350 XT (3M/ESPE) and randomly divided into four groups (n = 08) that were subjected to brushing simulation equivalent to the period of 1 month. The groups assessed were a control group with distilled water (G1), Colgate Total 12 Professional Clean (G2), Sensodyne Extra Whitener Extra Fresh (G3), and Colgate Luminous White (G4). A sequence of 90 cycles was performed for all the samples. The initial roughness of each group was analyzed by the Surface Roughness Tester (TR 200-TIME Group Inc., CA, USA). After the brushing period, the final roughness was measured, and the results were statistically analyzed using nonparametric Kruskal–Wallis and Dunn tests for intergroup roughness comparison in the time factor. For intragroup and “Δ Final − Initial” comparisons, the Wilcoxon test and (one-way) ANOVA were, respectively, performed (α = 0.05). Results: The roughness mean values before and after brushing showed no statistically significant difference when the different dentifrices were used. None of the dentifrices analyzed increased significantly the nanohybrid composite resin surface roughness in a 1 month of tooth brushing simulation. Conclusions: These results suggest that no hazardous effect on the roughness of nanohybrid composite resin can be expected when whitening dentifrices are used for a short period. Similar studies should be conducted to analyze other esthetic composite materials.

scholarly journals Comparative abrasive wear resistance and surface analysis of dental resin-based materials

2018 ◽  
Vol 12 (01) ◽  
pp. 057-066 ◽  
Author(s):  
Maleeha Nayyer ◽  
Shahreen Zahid ◽  
Syed Hammad Hassan ◽  
Salman Aziz Mian ◽  
Sana Mehmood ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Structural Changes ◽  
Wear Testing ◽  
Dental Resin ◽  
Force Microscopy ◽  
Atomic Force ◽  
Custom Made ◽  
Significant Difference ◽  
Before And After ◽  
Roughness Analysis

ABSTRACT Objective: The objective of this study was to assess the surface properties (microhardness and wear resistance) of various composites and compomer materials. In addition, the methodologies used for assessing wear resistance were compared. Materials and Methods: This study was conducted using restorative material (Filtek Z250, Filtek Z350, QuiXfil, SureFil SDR, and Dyract XP) to assess wear resistance. A custom-made toothbrush simulator was employed for wear testing. Before and after wear resistance, structural, surface, and physical properties were assessed using various techniques. Results: Structural changes and mass loss were observed after treatment, whereas no significant difference in terms of microhardness was observed. The correlation between atomic force microscopy (AFM) and profilometer and between wear resistance and filler volume was highly significant. The correlation between wear resistance and microhardness were insignificant. Conclusions: The AFM presented higher precision compared to optical profilometers at a nanoscale level, but both methods can be used in tandem for a more detailed and precise roughness analysis.

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