1.The effect of Er:YAG laser irradiation on the surface microstructure and roughness of TiO2 implant.
Jang Hyuk AN ; Young Hyuk KWON ; Joon Bong PARK ; Yeek HERR ; Jong Hyuk CHUNG
The Journal of the Korean Academy of Periodontology 2008;38(1):67-74
PURPOSE: The aim of this study was to evaluate the effect of Er:YAG laser on microstructure and roughness of TiO2 blasting implant surface. MATERIALS AND METHODS: Ten TiO2 blasting implant were used in this experiment. One implant was control group, and nine TiO2 blasting implant surfaces were irradiated with Er:YAG laser under 100 mJ/pulse, 140 mJ/pulse, and 180 mJ/pulse condition for 1 min, 1.5 min, and 2 min respectively. Optical interferometer and scanning electron microscopy was utilized to measure roughness and microstructure of specimens. RESULTS: The surface roughness was decreased after Er:YAG laser irradiation in all groups, but there was no significant difference. 100 mJ/pulse and 140 mJ/pulse group did not alter the TiO2 blasting implant surface in SEM study while 180 mJ/pulse group altered the TiO2 blasting implant surface. Implant surfaces showed melting, microfracture and smooth surface in 180 mJ/pulse group. CONCLUSION: Detoxification of implant surface using Er:YAG laser must be irradiated with proper energy output and irradiation time to prevent implant surface alteration.
Freezing
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Microscopy, Electron, Scanning
2.Morphology of the Terminal Segments of Megaselia scalaris (Loew) (Diptera: Phoridae) using Scanning Electron Microscopy
Raja Muhammad Zuha ; Atiah Ayunni Abdul Ghani
Malaysian Journal of Health Sciences 2016;14(2):141-143
Megaselia scalaris (Loew) (Diptera: Phoridae) is a cosmopolitan scuttle fly of medical and forensic importance. This species is generally small, humpbacked and is a prominent decomposer of corpses indoors. Taxonomically, adult sexes can be distinguished based on the characteristics of the terminal segments of the abdomen. In this report, the terminalia of adult male and female M. scalaris were examined using scanning electron microscope (SEM). The terminal segment of an adult female is less complex compared to male, consisting of an ovipositor and cerci. In male, the hypopygium consists of epandrium, hypandrium, anal tube and penis complex. A pair of long and feathered setae was attached to the tip of the anal tube and tapered. The application of SEM to identify this species isuseful and can be expanded to other species in this fly group.
Microscopy, Electron, Scanning
3.Comparison of mechanical properties of a new fiber reinforced composite and bulk filling composites.
Hazem ABOUELLEIL ; Nelly PRADELLE ; Cyril VILLAT ; Nina ATTIK ; Pierre COLON ; Brigitte GROSGOGEAT
Restorative Dentistry & Endodontics 2015;40(4):262-270
OBJECTIVES: The aim of this study was to evaluate the mechanical and physical properties of a newly developed fiber reinforced dental composite. MATERIALS AND METHODS: Fiber reinforced composite EverX Posterior (EXP, GC EUROPE), and other commercially available bulk fill composites, including Filtek Bulk Fill (FB, 3M ESPE), SonicFill (SF, Kerr Corp.), SureFil (SDR, Dentsply), Venus Bulk Fill (VB, HerausKultzer), Tetric evoceram bulk fill (TECB, Ivoclar Vivadent), and Xtra Base (XB, Voco) were characterized. Composite samples light-cured with a LED device were evaluated in terms of flexural strength, flexural modulus (ISO 4049, n = 6), fracture toughness (n = 6), and Vickers hardness (0, 2, and 4 mm in depth at 24 hr, n = 5). The EXP samples and the fracture surface were observed under a scanning electron microscopy. Data were statistically analyzed using one-way ANOVA and unpaired t-test. RESULTS: EXP, FB, and VB had significantly higher fracture toughness value compared to all the other bulk composite types. SF, EXP, and XB were not statistically different, and had significantly higher flexural strength values compared to other tested composite materials. EXP had the highest flexural modulus, VB had the lowest values. Vickers hardness values revealed SF, EXP, TECB, and XB were not statistically different, and had significantly higher values compared to other tested composite materials. SEM observations show well dispersed fibers working as a reinforcing phase. CONCLUSIONS: The addition of fibers to methacrylate-based matrix results in composites with either comparable or superior mechanical properties compared to the other bulk fill materials tested.
Hardness
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Microscopy, Electron, Scanning
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Venus
4.A Study on the Retentive Force of Stud Attachments for Implant Overdenture.
Eun Ju SONG ; Eun Bin BAE ; Jae Won CHOI ; Ji Hyeon BAE ; Ji Young KIM ; So Hyoun LEE
Journal of Dental Hygiene Science 2016;16(1):93-100
The purpose of this study was to compare the changes of retentive force in different stud attachment systems for implant retained overdenture. Two commercially available attachments with different retentive forces were investigated: Kerator (pink, blue, red) and O-ring (orange, red). Two implant fixtures were vertically embedded in base mountings. Five pairs of each attachment were evaluated. A universal testing machine was used to evaluate the retentive force of two attachments during wear simulation. Surface characteristics of each attachment system were evaluated with scanning electron microscopy. Five pairs of each attachment were evaluated. Kerator pink showed the highest initial retention. After 2,500 cycles of wear-simulation, Kerator pink noted the largest decrease in retention. According to results of surface analysis, Worn surfaces were obtained in matrices and patrices. Heavy wears were observed in matrices. After 2 year-wear simulation, most attachments exhibited retention loss. Attachments using different kind of material exhibited dissimilar surface alterations.
Denture, Overlay*
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Microscopy, Electron, Scanning
5.Scanning Electron Microscopy (SEM) investigation of Polystyrene damage due to colonization by locally isolated Xylaria sp.
Janine Erica D. ABECIA ; Mary Bernadette V. EGLOSO ; Mary Ann TAVANLAR ; Anna Theresa A. SANTIAGO
Philippine Journal of Health Research and Development 2019;23(1):64-70
BACKGROUND AND OBJECTIVES: Colonization of microorganisms on pollutants is the first indication of the potential ability of microbes to utilize plastic pollutants as a carbon source by sequential biodegradation into usable form for sustenance. The Philippines is considered the third highest country contributing to global mismanaged plastic waste. To locally manage and find a natural and innovative solution to this worldwide concern, this study aimed to evaluate the capacity of Xylaria sp. SDM (sterile dark mycelia) wild type, which was previously reported to colonize polyethylene plastic and mutant strains to colonize polystyrene, a plastic pollutant widely produced in the world. Assessment of the ability of local Xylaria sp. strains to grow, penetrate, and damage the surface and inner structures of polystyrene was investigated using scanning electron microscopy (SEM).
METHODOLOGY: Xylaria sp. strains were cultured in a pH 5.0 mineral medium with 0.5% glucose as carbon source and polystyrene as a co-carbon source, and stored at 25?C for 50 days. At the end of the incubation period, due to irremovable fungal strains on the surface of the polystyrene strips, samples of polystyrene from each strain were subjected to SEM.
RESULTS: On the 20th day of incubation, the presence of mucilaginous sheaths and fungal growth was observed on the surface of treated polystyrene strips. At the end of the 50-day incubation period, scanning electron microscopy (SEM) confirmed fungal growth and colonization, through the presence of mycelial mats and hyphae, of the wild type and mutant strains on the surface and inner structures of polystyrene except the control. Moreover, physical surface damage in the form of holes, cracks, and crevices on polystyrene demonstrated the active burrowing action of Xylaria sp. strains further supporting the potential of this fungus to damage polystyrene plastic.
CONCLUSION: Whereas fungal growth on a polymer surface is necessary but not sufficient to conclude the process of carbon assimilation as the final biodegradation step, the initial colonization of Xylaria sp. strains on polystyrene supports its ability to establish itself and physically damage the pollutant. Hence, this study extended the existing knowledge on the colonizing ability of Xylaria sp. on plastic making it a potential candidate organism to biodegrade plastic waste, which is one of the topmost environmental waste hazards in the world today.
Polystyrenes ; Plastics ; Microscopy, Electron, Scanning
6.The genus Hypoxylon, Wood Decay Fungi - II. Teleomorph of Annulata Section.
Mycobiology 2000;28(1):1-4
The section of Annulata under genus Hypoxylon is a member of the Xylariaceae which has ascomata with ostioles papillate ill a flattened disc. The isolates of Hypoxylon collected from the Tropic to the Temperate are compared with similar taxa and described. These isolations under Annulata section are illustrated with a light microscopy and a scanning electron microscopy. Hypoxylon archeri is newly recorded from Korea. A key to the species is also included.
Fungi*
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Korea
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Microscopy
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Microscopy, Electron, Scanning
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Wood*
7.Surface changes of metal alloys and high-strength ceramics after ultrasonic scaling and intraoral polishing.
Hyung In YOON ; Hyo Mi NOH ; Eun Jin PARK
The Journal of Advanced Prosthodontics 2017;9(3):188-194
PURPOSE: This study was to evaluate the effect of repeated ultrasonic scaling and surface polishing with intraoral polishing kits on the surface roughness of three different restorative materials. MATERIALS AND METHODS: A total of 15 identical discs were fabricated with three different materials. The ultrasonic scaling was conducted for 20 seconds on the test surfaces. Subsequently, a multi-step polishing with recommended intraoral polishing kit was performed for 30 seconds. The 3D profiler and scanning electron microscopy were used to investigate surface integrity before scaling (pristine), after scaling, and after surface polishing for each material. Non-parametric Friedman and Wilcoxon signed rank sum tests were employed to statistically evaluate surface roughness changes of the pristine, scaled, and polished specimens. The level of significance was set at 0.05. RESULTS: Surface roughness values before scaling (pristine), after scaling, and polishing of the metal alloys were 3.02±0.34 µm, 2.44±0.72 µm, and 3.49±0.72 µm, respectively. Surface roughness of lithium disilicate increased from 2.35±1.05 µm (pristine) to 28.54±9.64 µm (scaling), and further increased after polishing (56.66±9.12 µm, P<.05). The zirconia showed the most increase in roughness after scaling (from 1.65±0.42 µm to 101.37±18.75 µm), while its surface roughness decreased after polishing (29.57±18.86 µm, P<.05). CONCLUSION: Ultrasonic scaling significantly changed the surface integrities of lithium disilicate and zirconia. Surface polishing with multi-step intraoral kit after repeated scaling was only effective for the zirconia, while it was not for lithium disilicate.
Alloys*
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Ceramics*
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Lithium
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Microscopy, Electron, Scanning
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Ultrasonics*
8.Isolation and Identification of Melanosomes from Human Hair.
Sung Bin IM ; Sung Nack LEE ; Kyu Woong HAHN
Annals of Dermatology 1991;3(1):12-14
Melanosomes were isolated from the human hair by graded centrifugation and identified by transmission and scanning electron microscopic examination. Melanosomes were separated from the keratinous structures by treating with strong NaOH solution for 15 hours. The keratinous structures were removed by centrifugation ai 2,500xg and 3,500xg for 10 minutes respectively at 0 ℃. The isolated melanosomes were collected by centrifugation at 7,800xg at 0 ℃. Scanning electron microscopic examination made it possible to evaluate the global structure of purified melanosomes.
Centrifugation
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Hair*
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Humans*
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Melanosomes*
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Microscopy, Electron, Scanning
9.First Report of Clavinema mariae (Nematoda: Philometridae) in Cultured Rockfish, Sebastes schlegeli, in Cheonsuman (Bay), the Republic of Korea.
Hyun Ja HAN ; Jung Soo SEO ; Jeong Su PARK ; Haeng Lim LEE ; Han Gill SEO ; Sung Hee JUNG ; Se Ryun KWON
The Korean Journal of Parasitology 2017;55(2):219-224
In July 2012, philometrid nematodes were discovered in cultured rockfish (Sebastes schlegeli) in Cheonsuman (Bay), the Republic of Korea. The nematodes were detected in the epithelial tissues of the rockfish and were identified as Clavinema mariae based on morphological studies using light and scanning electron microscopy. They revealed the characteristics same as previously identified C. mariae, notably having a long body with narrow posterior half, no caudal projection, a cylindrical-shaped esophagus, a well-developed anterior bulbous part of the esophagus, cephalic papillae, and a dorsal esophageal gland. This is the first confirmation of C. mariae infection in rockfish in Korea.
Esophagus
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Korea
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Microscopy, Electron, Scanning
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Republic of Korea*
10.Cytotoxicity of temporary cements on bovine dental pulp-derived cells (bDPCs) using realtime cell analysis.
Meral Arslan MALKOC ; Necla DEMIR ; Abdulkadir SENGUN ; Serife Buket BOZKURT ; Sema Sezgin HAKKI
The Journal of Advanced Prosthodontics 2015;7(1):21-26
PURPOSE: To evaluate the cytotoxicity of temporary luting cements on bovine dental pulp-derived cells (bDPCs). MATERIALS AND METHODS: Four different temporary cements were tested: Rely X Temp E (3M ESPE), Ultratemp (Ultradent), GC Fuji Temp (GC), and Rely X Temp NE (3M ESPE). The materials were prepared as discs and incubated in Dulbecco's modified eagle's culture medium (DMEM) for 72 hours according to ISO 10993-5. A real-time cell analyzer was used to determine cell vitality. After seeding 200 microL of the cell suspensions into the wells of a 96-well plate, the bDPCs were cured with bioactive components released by the test materials and observed every 15 minutes for 98 hours. One-way ANOVA and Tukey-Kramer tests were used to analyze the results of the proliferation experiments. RESULTS: All tested temporary cements showed significant decreases in the bDPCs index. Rely X Temp E, GC Fuji Temp, and Rely X Temp NE were severely toxic at both time points (24 and 72 hours) (P<.001). When the cells were exposed to media by Ultratemp, the cell viability was similar to that of the control at 24 hours (P>.05); however, the cell viability was significantly reduced at 72 hours (P<.001). Light and scanning electron microscopy examination confirmed these results. CONCLUSION: The cytotoxic effects of temporary cements on pulpal tissue should be evaluated when choosing cement for luting provisional restorations.
Cell Survival
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Microscopy, Electron, Scanning
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Suspensions