scholarly journals A randomised controlled study on the use of finishing and polishing systems on different resin composites using 3D contact optical profilometry and scanning electron microscopy

2018 ◽  
Vol 71 ◽  
pp. 25-30 ◽  
Author(s):  
Alaa Daud ◽  
Gordon Gray ◽  
Christopher D. Lynch ◽  
Nairn H.F. Wilson ◽  
Igor R. Blum
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Controlled Study ◽  
Resin Composites ◽  
Optical Profilometry ◽  
Randomised Controlled Study ◽  
Randomised Controlled ◽  
Scanning Electron

scholarly journals Efficacy of one-step and multi-step polishing systems in finishing direct composite restoration: a non-randomised controlled experimental trial

2021 ◽  
Vol 28 (3) ◽  
pp. 29-45
Author(s):  
O. A. Pavlovich ◽  
I. A. Vykhristyuk ◽  
V. Yu. Buzko ◽  
V. V. Pavlovich
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Surface Roughness ◽  
Design And Technology ◽  
Scientific Instrument ◽  
Optical Profilometry ◽  
Average Roughness ◽  
Randomised Controlled ◽  
Diamond Abrasive ◽  
Scanning Electron

Background. The variety of polishing systems and tools available for finishing direct composite restorations may perplex the dentist.Objectives. An effect evaluation in one- and multi-step composite polishing tools using model specimens of GC Gradia Direct and 3M ESPE Filtek Ultimate restoratives.Methods. The prepared specimens of GC Gradia Direct and 3M ESPE Filtek Ultimate restorative composites were exposed in laboratory to the Kenda Maximus, Dentsply PoGo, Kagayaki RoundFlex, Shofu Super-Snap, Kagayaki Ensmart Pin, EVE Composoft polishing systems and Daiyamondo Kagayaki paste. The polishing systems distinguished by brand, technical and performance characters.Surface microgeometry in all 16 samples was estimated in the Laboratory of Optical Metrology, Institute of Design and Technology for Scientific Instrument Engineering, Novosibirsk, using a MNP-1 light interferometric nanoprofile microscope and at the shared core facilities of the Research and Education Centre “Nanomaterial Diagnostics and Properties” of Kuban State University, Krasnodar, using a JEOL JSM-7500F scanning electron microscope.Results. Optical profilometry and scanning electron microscopy were used to estimate surface roughness in 16 specimens exposed to polishing for one minute. The polishing tools Kenda Maximus, Dentsply PoGo, Kagayaki RoundFlex, Shofu Super-Snap, Kagayaki Ensmart Pin, EVE Composoft, as well as Daiyamondo Kagayaki paste used in instrumental polishing, revealed a varied performance. Optical profilometry exhibited the GC Gradia Direct and Filtek Ultimate specimens to possess the lowest average roughness in two cases: 1) after multi-step polishing with Kagayaki Ensmart Pin tools with Daiyamondo Kagayaki paste (average roughness corresponded to Sa — 0.214 pm in GC Gradia Direct and Sa — 0.248 pm — in Filtek Ultimate), 2) in application of the Kenda Maximus monopolishing tool (roughness values of Sa — 0.211 and Sa — 0.242 pm, respectively). Surface roughness after multi-step machining with EVE Composoft silicone polishers was average Sa — 0.579 and Sa — 0.549 pm in both samples and was reported the highest. Scanning electron microscopy confirmed the optical profilometry estimates.Conclusion. The assay showed that the specimen machining with a sole Kenda Maximus diamond abrasive tool and several Kagayaki Ensmart Pin silicone polishing heads followed by a Daiyamondo Kagayaki diamond abrasive paste application produced very similar surface roughness values, which were graded the lowest with GC Gradia Direct and 3M ESPE Filtek Ultimate composite samples using scanning electron microscopy and optical profilometry.

scholarly journals Thermal properties of porcelain reinforced polyester resin composites

2017 ◽  
Vol 52 (2) ◽  
pp. 147-152
Author(s):  
R Sultana ◽  
R Akter ◽  
MR Qadir ◽  
MA Gafur ◽  
MZ Alam
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Thermal Properties ◽  
Polyester Resin ◽  
Compression Molding ◽  
Resin Composites ◽  
Thermal Stabilities ◽  
Degradation Temperature ◽  
Scanning Electron ◽  
Thermal Conductivities

Porcelain reinforced polyester resin composites (PPCs) having different compositions have been prepared by compression molding. Thermal properties of PPCs were studied by means of TG-DTA and TMA. The influence of porcelain content on thermal properties of PPCs was studied in detail. Thermal conductivities of PPCs decreased from 0.00068 cal/cm sec°C to 0.00030 cal/cm sec°C by the addition of porcelain from 10 to 60%. The results of this study reveal their good thermal stabilities. The 50% degradation temperature of pure Polyester resin was 401.5°C, but that of the PPC-1, PPC-2 and PPC-4 were 406.3°C, 407.8°C, and 417.3°C respectively. The morphology of the composites was studied with scanning electron microscopy (SEM).Bangladesh J. Sci. Ind. Res. 52(2), 147-152, 2017

scholarly journals Comparison of chemical composition of packable resin composites by scanning electron microscopy

2005 ◽  
Vol 13 (1) ◽  
pp. 67-71 ◽  
Author(s):  
Ana Amélia Bianchi e Silva ◽  
Elaine Bauer Veeck ◽  
José Pedro Peixoto de Oliveira ◽  
Paulo Henrique Couto Souza
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Chemical Composition ◽  
Chemical Components ◽  
Resin Composites ◽  
X Ray ◽  
Scanning Electron

OBJECTIVES: the purpose of this study was to compare the chemical composition of four different shades (incisal/extra-light, A2, A3 and B3) of two packable resin composites (SOLITAIRE®, and PRODIGY CONDENSABLE TM). METHODS AND MATERIALS: the specimens measured 4mm in diameter and 4mm in thickness. Five specimens were made for each shade of the materials. They were light cured for 40 seconds at a power of 600mW/cm². Subsequently, the specimens were removed from the plates and ground to powder and then pressed into holes measuring 4mm in diameter in a Teflon matrix, using the plates of the same material as base and cover. Specimens were evaluated under SEM with an x-ray detector for the spectroscopic test by energy dispersing. RESULTS: the chemical components found in both materials were practically the same, but in different proportions. Carbon, Oxygen, Aluminum, Silica, Fluoride and Barium were found. CONCLUSIONS: the chemical composition of each same material varied according to each shade analyzed.

Experimental Single Controlled Study of Burned Bones: Contribution of Scanning Electron Microscopy

1998 ◽  
Vol 43 (2) ◽  
pp. 16160J ◽  
Author(s):  
Gérald Quatrehomme ◽  
Marc Bolla ◽  
Michèle Muller ◽  
Jean-Paul Rocca ◽  
Gilles Grévin ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Controlled Study ◽  
Burned Bones ◽  
Scanning Electron

Clinical and Micromorphologic 29-year Results of Posterior Composite Restorations

2018 ◽  
Vol 97 (13) ◽  
pp. 1431-1437 ◽  
Author(s):  
R. Montag ◽  
W. Dietz ◽  
S. Nietzsche ◽  
T. Lang ◽  
K. Weich ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Failure Rate ◽  
Glass Ionomer Cement ◽  
Nonparametric Tests ◽  
Controlled Study ◽  
Secondary Caries ◽  
Composite Restorations ◽  
Marginal Integrity ◽  
Scanning Electron

Prospective clinical studies of composite restorations revealed their safety and longevity; however, studies did not elucidate the dynamic mechanisms of deterioration caused by fractures and secondary caries. Therefore, the aims of this 29-y controlled study were 1) to follow up on the clinical behavior of posterior composite restorations annually and 2) to compare clinical outcomes with micromorphologic scanning electron microscopy features. After ethical approval, the single-arm study commenced in 1987 with 194 class I or II primary posterior composite restorations with glass ionomer cement providing pulp protection. Each restoration was evaluated annually for 15 y and then again at 29 y per the US Public Health Service–compatible Clinical, Photographic and Micromorphologic coding index, with clinical and photographic criteria for anatomic form, color matching, surface quality, wear, marginal integrity, secondary caries, and clinical acceptability. Parallel micromorphologic criteria were applied at baseline and after 1, 3, 5, 7, 10, 15, and 29 y to assess surface roughness, texture, marginal integrity, fractures, ledges, and marginal gaps with semiquantitative coding and with quantitative 3-dimensional scanning electron microscopy profilometric measurements of marginal grooves next to the enamel, grooves within the bonding zone, and ledges. Statistical analysis included the calculation of the annual failure rate and the use of Kaplan-Meier methodology and nonparametric tests. The cumulative survival rates were 91.7% (6 y), 81.6% (12 y), and 71.4% (29 y). The mean annual failure rate was 1.92%. Significant changes in the restoration-tooth interface from baseline to 5 y resulted in functional masticatory equilibrium. Clinical deterioration year by year, including micromorphologic microfractures and wear, reflected unique dynamic changes in long-term surviving restorations with very low secondary caries and fracture risks (German Network for Health Care Research VfD 29 99 003924).

Scanning Electron Microscopy and Optical Profilometry of Electropolished Additively Manufactured 316 Steel Components

2018 ◽  
Author(s):  
Pawan Tyagi ◽  
Tobias Goulet ◽  
Denikka Brent ◽  
Kate Klein ◽  
Francisco Garcia-Moreno
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Surface Roughness ◽  
Smooth Surface ◽  
High Surface ◽  
Fatigue Loading ◽  
Surface Finishing ◽  
Optical Profilometry ◽  
Premature Failure ◽  
Scanning Electron

Additive manufacturing (AM) can produce highly complex engineering components that are either extremely challenging for the conventional subtractive manufacturing route or not possible otherwise. High surface roughness can make an AM component highly vulnerable to premature failure during fatigue loading. Post-processing aiming to reduce surface roughness is essential to make as produced AM parts functional. We have explored electropolishing route to achieve optimum surface roughness and surface chemistry. We have performed electropolishing treatment on the steel AM parts around 70 °C in an electrolyte comprising the phosphoric acid and sulfuric acid. Profilometry and scanning electron microscopy were performed to study the electropolished and unpolished areas. Optical profilometry study showed that one needs to remove nearly ∼200 μm material from the surface to achieve very smooth surface. Electropolishing was effective in reducing the surface Ra roughness from ∼2 μm rms to ∼0.07 μm rms. Such low rms roughness makes an AM component suitable for almost every engineering application for which a smooth surface is required. Scanning electron microscopy revealed that electropolished area on AM component possessed distinctively different microstructure as compared to the untreated surface of an AM component. We also conducted the compositional analysis of the electropolished area to investigate the possibility of residual contamination from the electropolishing process. Our study revealed that electropolishing is a highly promising route for improving the surface finishing of AM components.

Pathogenesis of Human Hair Defects

1974 ◽  
Vol 32 ◽  
pp. 12-13
Author(s):  
P.S. Porter ◽  
T. Aoyagi ◽  
R. Matta
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Human Hair ◽  
Standard Techniques ◽  
Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

Ultrastructural Analysis of the Salivary Glands of Gromphadorhina Portentosa (Schaum)

1977 ◽  
Vol 35 ◽  
pp. 638-639
Author(s):  
P.J. Dailey
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Salivary Glands ◽  
Secretory Vesicles ◽  
The Past ◽  
Transmission Electron ◽  
Means Of Transmission ◽  
Gromphadorhina Portentosa ◽  
Scanning Electron ◽  
Topographical Relief

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.

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