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.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
4.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
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.Damage and Regeneration of Hair Cuticles After Permanent Coloring: Sequential Microscopic Changes.
Soo Jung KIM ; Won Soo LEE ; Eung Ho CHOI ; Sung Ku AHN
Korean Journal of Dermatology 1996;34(2):257-263
BACKGROUND: The effects of external chemicals on the hair shaft are of great interest in both the medical field and the cosmetic industry. Current methods to analyze these effects consist mainly of macroscopic testing such as touch and tell little about the actual hair morphology. OBJECT: The purpose of the present study was to evaluate the morphologic changes of hair shaft, especially cuticle, after aoplication of permanent dye. METHODS: The coloring was performed as routine procedures. The time of contact of the dyeing solution within the scalp and hair was 30minutes. The coloring process ends with a through rinsing with water, Scanning electron microscopic findings of hair cuticle was observed sequentially before and after application of hair dye. RESULTS: After 30minutes, cuticular swelling without degeneration was seen As the swelling improve, the cuticular degradation was noted initially at 90minutes, By the 2 hours to the 1 week gradual progression of cuticular degradation was noted. By 1week after coioring, cortical exposure due to extensive cuticular detachment was observed. The reaction reached a peak between 1 and 2 weeks. Then, damaged outicles were gradually regenerated and returned to pre-treatment states by 8weeks. CONCLUSION: The hair fibers take l month to grow out by 1cm, at which point a fresh dye application becomes necessary. However, aithough the cuticles were regenerating, the cuticular damage still remained after 6 weeks. So, we concluded that interval of coloring is required more than 8 weeks. But further study to protect cuticle and to improve regeneration will be needed for shortening of regeneration time.
Hair*
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Microscopy, Electron, Scanning
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Regeneration*
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Scalp
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Water
8.Damage and Regeneration of Hair Cuticles After Permanent Coloring: Sequential Microscopic Changes.
Soo Jung KIM ; Won Soo LEE ; Eung Ho CHOI ; Sung Ku AHN
Korean Journal of Dermatology 1996;34(2):257-263
BACKGROUND: The effects of external chemicals on the hair shaft are of great interest in both the medical field and the cosmetic industry. Current methods to analyze these effects consist mainly of macroscopic testing such as touch and tell little about the actual hair morphology. OBJECT: The purpose of the present study was to evaluate the morphologic changes of hair shaft, especially cuticle, after aoplication of permanent dye. METHODS: The coloring was performed as routine procedures. The time of contact of the dyeing solution within the scalp and hair was 30minutes. The coloring process ends with a through rinsing with water, Scanning electron microscopic findings of hair cuticle was observed sequentially before and after application of hair dye. RESULTS: After 30minutes, cuticular swelling without degeneration was seen As the swelling improve, the cuticular degradation was noted initially at 90minutes, By the 2 hours to the 1 week gradual progression of cuticular degradation was noted. By 1week after coioring, cortical exposure due to extensive cuticular detachment was observed. The reaction reached a peak between 1 and 2 weeks. Then, damaged outicles were gradually regenerated and returned to pre-treatment states by 8weeks. CONCLUSION: The hair fibers take l month to grow out by 1cm, at which point a fresh dye application becomes necessary. However, aithough the cuticles were regenerating, the cuticular damage still remained after 6 weeks. So, we concluded that interval of coloring is required more than 8 weeks. But further study to protect cuticle and to improve regeneration will be needed for shortening of regeneration time.
Hair*
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Microscopy, Electron, Scanning
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Regeneration*
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Scalp
;
Water
9.Effects of recycling on the biomechanical characteristics of retrieved orthodontic miniscrews.
Soon Dong YUN ; Sung Hwan CHOI ; Jung Yul CHA ; Hyung Seog YU ; Kwang Mahn KIM ; Jin KIM ; Chung Ju HWANG
The Korean Journal of Orthodontics 2017;47(4):238-247
OBJECTIVE: The aim of this study was to compare recycled and unused orthodontic miniscrews to determine the feasibility of reuse. The comparisons included both miniscrews with machined surfaces (MS), and those with etched surfaces (ES). METHODS: Retrieved MS and ES were further divided into three subgroups according to the assigned recycling procedure: group A, air-water spray; group B, mechanical cleaning; and group C, mechanical and chemical cleaning. Unused screws were used as controls. Scanning electron microscopy, energy-dispersive X-ray spectrometry, insertion time and maximum insertion torque measurements in artificial bone, and biological responses in the form of periotest values (PTV), bone–implant contact ratio (BIC), and bone volume ratio (BV) were assessed. RESULTS: Morphological changes after recycling mainly occurred at the screw tip, and the cortical bone penetration success rate of recycled screws was lower than that of unused screws. Retrieved ES needed more thorough cleaning than retrieved MS to produce a surface composition similar to that of unused screws. There were no significant differences in PTV or BIC between recycled and unused screws, while the BV of the former was significantly lower than that of the latter (p < 0.05). CONCLUSIONS: These results indicate that reuse of recycled orthodontic miniscrews may not be feasible from the biomechanical aspect.
Microscopy, Electron, Scanning
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Recycling*
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Spectrum Analysis
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Torque
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