Influence of Dental Humidity on Marginal Adaptation of Biodentine Restorations

Biodentine is a tricalcium silicate cement used as a dentin replacement in restorative dentistry. The aim of this study was to assess the influence of cavity moisture on the immediate sealing and morphology of the interface between Biodentine and the dental tissues. 20 class II cavities were prepared in extracted teeth. 10 cavities were dried using the air spray before restoring with Biodentine and 10 cavities were preserved moist for the restorative procedure. The teeth were subjected to a microleakage test and then the axial sections were observed under optical microscope and scanning electron microscope. In most situations Biodentine provided an immediate good marginal sealing and a tide contact with adjacent tissues in both occlusal and cervical margins which did not seem to be influenced by the moisture of the dental supporting tissues.

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Effect of Casting Overheat and Rolling Temperature on Morphology of Sulfide in 30MnVS Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.457-458.270 ◽

2012 ◽

Vol 457-458 ◽

pp. 270-273

Author(s):

Yi You Tu ◽

Guo Zhong Li

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Continuous Casting ◽

Optical Microscope ◽

Rolling Temperature ◽

Ferrite Content ◽

Continuous Casting Slab ◽

Intragranular Ferrite ◽

Sulfide Segregation ◽

Scanning Electron

Effect of superheat and initial rolling temperature on the morphology and distribution of sulfide in non quenched and tempered free cutting steel 30MnVS has been studied by optical microscope and scanning electron microscope. Results show that proper superheat and initial rolling temperature can turn rod-shaped sulfide into massive or globular sulfide，to alleviate sulfide segregation and pro-eutectoid ferrite distribution along the boundary of pearlite clusters in 30MnVS , increase the intragranular ferrite content and optimize the structure of continuous casting slab.

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Analysis of an Axle Failure under Torsional Load

Materials Science Forum ◽

10.4028/www.scientific.net/msf.850.101 ◽

2016 ◽

Vol 850 ◽

pp. 101-106 ◽

Cited By ~ 1

Author(s):

Shu Mei Li ◽

Jian Jun Yang ◽

Wei Dong Zhang ◽

August Chang ◽

Cai Xia Zhang ◽

...

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Failure Mechanism ◽

Field Testing ◽

Optical Microscope ◽

Fatigue Lifetime ◽

Torsional Load ◽

Torsional Fatigue ◽

Secondary Cracks ◽

Scanning Electron

Premature fracture of an axle under torsional load occurred after a tracked military tank had experienced field testing for only 80 kilometers. Visual metallographic examinations were performed with optical microscope (OM) and scanning electron microscope (SEM). The investigation demonstrates that the premature fracture is caused by metallurgical problems inside the axle where the primary and secondary cracks originate, propagate, and eventually result in final catastrophic rupture through torsional fatigue. The failure mechanism is summarized and improvement of the fatigue lifetime for the axle is recommended.

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4349242 Specimen observation apparatus including an optical microscope and a scanning electron microscope

Micron and Microscopica Acta ◽

10.1016/0047-7206(83)90082-1 ◽

1983 ◽

Vol 14 (3) ◽

pp. 290

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Optical Microscope ◽

Scanning Electron

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Investigation on the Microstructure Hardness for the Hot Compressed Duplex Steel

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.905.30 ◽

2022 ◽

Vol 905 ◽

pp. 30-37

Author(s):

Shu Lan Zhang ◽

Xiao Dan Zhang ◽

Hai Feng Xu ◽

Chang Wang

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Optical Microscope ◽

Ferrite Phase ◽

Ferrite Formation ◽

Average Hardness ◽

Duplex Steel ◽

Quench Temperature ◽

Fluctuation Range ◽

Scanning Electron

Effect of microstructure size and type on the hardness for the duplex steel were disclosed by using of optical microscope (OM), scanning electron microscope (SEM) and nanoindenter for the samples hot compressed under different temperature with reduction of 10%, 30%, 50% and 70%. OM and SEM were used to measure the average martensite lamellar width, space and indenter morphology. nanoindenter test characterized the microstructure hardness for the samples under different process. Experiment results show that martensite hardness for the sample hot compressed at 950°C has larger diversity than that of sample hot compressed at 1200°C. The martensite hardness fluctuation range for the sample compressed at 950°C is almost from about 7GPa to 12GPa, while, for the sample compressed at 1200°C, the fluctuation range is basically from about 9GPa to 12GPa. However, the average hardness for the samples hot compressed at 950°C is comparably smaller, which is related with lower quench temperature. The larger martensite hardness fluctuation is mainly related with induced ferrite formation and finer martensite lamellar width. For the ferrite phase, the hardness fluctuation range is lower.

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CHARACTERISATION OF BIOMEDICAL TITANIUM LAYERS DEPOSITED BY A VACUUM PLASMA SPRAY PROCESS

Materiali in tehnologije ◽

10.17222/mit.2020.135 ◽

2021 ◽

Vol 55 (2) ◽

pp. 231-235

Author(s):

Mihailo Mrdak ◽

Darko Bajić ◽

Darko Veljić ◽

Marko Rakin

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Hardness Test ◽

Optical Microscope ◽

Mechanical Tests ◽

Test Method ◽

Bonding Layer ◽

Vacuum Plasma Spray ◽

Porous Ti ◽

Scanning Electron

In this paper we will describe the process of the deposition of thick layers of VPS-Ti coating, which is used as a bonding layer for the upper porous Ti coatings on implant substrates. In order to deposit the powder, we used HÖGANÄS Ti powder labelled as AMPERIT 154.086 -63 µm. In order to test the mechanical properties and microstructure of the VPS-Ti coating, the powder was deposited on Č.4171 (X15Cr13 EN10027) steel substrates. Mechanical tests of the microhardness of the coating were performed by the Vickers hardness test method (HV0.3) and tensile strength by measuring the force per unit area (MPa). The microhardness of the coating is 159 HV0.3, which is consistent with the microstructure. The coating was found to have a good bond strength of 68 MPa. The morphology of the powder particles was examined on a scanning electron microscope. The microstructure of the coating, both when deposited and etched, was examined with an optical microscope and a scanning electron microscope. By etching the coating layers, it was found that the structure is homogeneous and that it consists of a mixture of low-temperature and high-temperature titanium phases (α-Ti + β-Ti). Our tests have shown that the deposited layers of Ti coating can be used as a bonding layer for porous Ti coatings in the production of implants.

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Clouding of Pressed Potassium Bromide Powder

Applied Spectroscopy ◽

10.1366/000370272774352236 ◽

1972 ◽

Vol 26 (2) ◽

pp. 247-251 ◽

Cited By ~ 8

Author(s):

William P. Norris ◽

Allen L. Olsen ◽

Richard G. Brophy

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Adsorbed Water ◽

Optical Microscope ◽

Potassium Bromide ◽

Monomolecular Layer ◽

Cloudy Region ◽

Weak Zones ◽

Ground Powder ◽

Scanning Electron

The monomolecular layer of water adsorbed on KBr particles is responsible for clouding of disks pressed from finely ground powder. Cloudiness is caused by formation of a multitude of cracks in the disk. The initial cracking can be observed with a low power optical microscope and the extensive cracking in the fully cloudy region is observable with a scanning electron microscope. It is suggested that adsorbed water promotes recrystallization, generating weak zones in the workhardened, elastically stressed disk which fails by cracking.

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Influence of prophylaxis on the microleakage of sealants: in vitro study

Journal of Clinical Pediatric Dentistry ◽

10.17796/jcpd.26.4.v8lm755w4n414113 ◽

2002 ◽

Vol 26 (4) ◽

pp. 371-375 ◽

Cited By ~ 1

Author(s):

Ana Beatriz Alonso Chevitarese ◽

Orlando Chevitarese ◽

Ivete Pomarico Ribeiro de Souza ◽

Roberto Braga de Carvalho Vianna

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

In Vitro Study ◽

Optical Microscope ◽

Vitro Study ◽

Significant Difference ◽

Group A ◽

Group B ◽

Scanning Electron

The aim of this study was to evaluate the influence of prophylaxis on the sealants microleakage in 30 premolars divided into: Group A, Group B and Group C. The teeth were analyzed using the optical microscope (OM) and at scanning electron microscope (SEM). There was a statitical significant difference among the groups regarding the presence of microleakage, but not with the presence of tags.

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Ion Etching of Dental Tissues in a Scanning Electron Microscope

Nature ◽

10.1038/196081a0 ◽

1962 ◽

Vol 196 (4849) ◽

pp. 81-82 ◽

Cited By ~ 18

Author(s):

A. D. G. STEWART ◽

A. BOYDE

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Ion Etching ◽

Dental Tissues ◽

Scanning Electron

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SEM analysis of dental enamel morphological structures on the basis of their replicas in patients with systemic calcium deficiency

Open Life Sciences ◽

10.2478/s11535-009-0007-3 ◽

2009 ◽

Vol 4 (2) ◽

pp. 190-195

Author(s):

Ewa Bałczewska ◽

Leszek Klimek ◽

Aleksandra Palatyńska-Ulatowska

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Periodontal Diseases ◽

Dental Enamel ◽

Microscopic Analysis ◽

Calcium Deficiency ◽

Sem Analysis ◽

Mineral Density ◽

Dental Tissues ◽

Scanning Electron

AbstractThe aim of the present study is to examine microscopically the surface of dental enamel by using a scanning electron microscope (SEM), using their replicas formed in female patients with diagnosed periodontal diseases and systemic calcium deficiency. Replicas of dental enamel surfaces in patients referred for treatment of periodontal diseases were subjected to microscopic analysis. The replicas, after coating with platinum-palladium alloy, were examined under the scanning electron microscope at magnifications of 15–5000 x. Densitometric examinations of spine (L2 - L4 segment) revealed bone mineral density BMD T-score lower than −2.5 in 5 patients, in the range of −1.5 to −2.5 in 10 patients, and higher than −1.5 in the remaining patients. Non-homogenous images of surfaces in the form of light and dark areas were observed. Light areas corresponded to damaged surfaces of dental tissues. Patients with higher systemic calcium deficiency had areas lighter in color. More of these areas were found in patients with higher systemic calcium deficiency. It can be assumed that the calcium deficit is likely to appear in the selected dental tissues, particularly in the dental enamel.

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