• Resources Recycling
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• v.8 no.1
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• pp.11-17
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• 1999

This study was carried out to investigate the efficiency of stcclmaldng slag and sludge in removing metals existing in wastewater or leachate. Laboratory experiments were performed as a function of initial concentration of metals. pH a and temperature of the background solution and the presence of che1ating agent, EDTA. The test conditions were temperatures r ranging from $25^{\circ}C$ to $50^{\circ}C$; initial concentrations varying from 5mg/L to 50 mg/L; pH between 3 and 11; and Cu. Cd‘ and Pb a as adsorbates. The results of tests showed that overall rates of metals removal were 20~30% at pH 3 and greater than 90% at p pH 7 and 11. Metals were removed from the solution predominantly via adsorption in acidic conditions, and the combined e effects of adsorption and precipitation in neutral and alkaline conditions. In view of the test results and other engineering c characteristics of steelmaking slag and sludg$\xi$, these industrial by-products from steel industry have a high potential to be used l in wastewater treatment and are particularly beneficial when used as landfill liner additives due to thelJ ability to remove heavy m metals from leachate.

• Journal of the East Asian Society of Dietary Life
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• v.11 no.3
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• pp.190-195
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• 2001

The objective of this study consists in finding the ways to make soybean cake (which is made of soaked soybean flour containing protein and lipid) a scientific and practical food even more easily. This study took a measurement of the change of pH, organic acid, microorganism, retrogradation and so soon. observing soybean cake prepared with soybean flour containing 6% of soybean oil at room temperature(19$^{\circ}C$) in two types of packaging, that is to say, $CO_2$ modified packing(CMP) and liner low density poly ethylene(LLDPE) packaging. As storing time went by, packed soybean cake didn't appeared in 12 days, either. Using modified atmosphere packaging soybean cake showed higer pH as well as less organic acid than unpacked. In addition, mould method makes water - activity lower, and it Puts a curb on the development of aerobic perishable microorganism and the retrogradation of rice cake. Unpacked soybean cake showed higher values than CMP Soybean Cake with enthalpy of retrogradation and the longer storing period the greater retrogradation process. Thus, storing or circulation period can be increased effectively without chemical or physical treatment.

• The Journal of Korean Physical Therapy
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• v.16 no.3
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• pp.50-64
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• 2004

The studies have been designed to evaluate the effect of wound healing of pulsed ultrasound and chitosan application in diabetic incisive wound of rats. Mild diabetes mellitus was induced in rat used 30 mg/kg streptozotocin. Full thickness skin incision was made on the backs of Sprague-Dawley rats. We used 72 Sprague-Dawley rats which were divided into 4 groups; the subjects were divided into group of 6 rats each 3, 6, and 15 days. The results were summarized as follows; The rate of wound length of pulsed ultrasound with chitosan application groups more decreased than only pulsed ultrasound treatment group. The density of inflammatory cells in the experimental groups was more significantly decreased than diabetic control group(p<0.05). Historically, in the ultrasound with chitosan application groups, reepithelized epithelium was thicker and the collagen fiber were organized in a liner manner and connective tissue was matured faster those of the diabetic control group(p<0.05). From the conclusions above, in this study application of pulsed ultrasound and chitosan can be an effective way of promotion of wound healing in diabetic model.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.5
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• pp.47-52
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• 2008

The far-infrared ray (FIR) has been applied to various fields such as medical therapy, kitchen utensils, bath supplies, and so on. The FIR-emitting agent was used to make functional paperboards to have freshness-maintaining ability. The FIR-emitting agent was diluted with different concentrations at 0.5% starch solution, and the FIR-emitting solutions were coated on paperboards, i.e., liner. The more the concentration of the FIR radiating agent increased at 0.5% cationic starch solution, the higher FIR emissivity and emission power of paperboards increased. The corrugated boxes made of paperboards coated by the FIR-radiating agents at over 5% dilution concentration endowed mandarin oranges in the boxes with greater antimicrobial activity than those in boxes made of paperboards coated by the agent at below 5% concentration. In addition, it was ascertained that treatment of the FIR agents rarely affected strength properties of paperboards.

• The Journal of Advanced Prosthodontics
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• v.7 no.3
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• pp.191-198
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• 2015

PURPOSE. The purpose of this study was to compare the coronal bone level and patient satisfaction in 1-implant and 2-implant assisted mandibular overdentures. MATERIALS AND METHODS. Twenty patients who had maladaptive mandibular dentures were treated in this study. Patients were randomly divided into two groups. The first group received 1 implant (Simple line II, Implantium, South Korea) in their mandibular midline and the second group received 2 implants in their B and D regions (according to Misch's category). If the primary stability of each implant was at least 60 ISQ, ball attachment was placed and denture relined with soft liner. After 6 weeks, retentive cap incorporated with hard acrylic resin. In the 6 and 12 months recalls, periapical digital radiograph were made and visual analogue scale questionnaires were used to record patient satisfaction. The Friedman test was done for comparing the presurgical and postsurgical parameters in each group and the U-Mann Whitney test (P<.05) was done for comparison of post-treatment results between the two groups. RESULTS. All implants achieved sufficient primary stability to be immediately loaded. Patient satisfaction was high, and there were no significant differences between two groups (P>.05). In addition, mean marginal bone loss was $0.6{\pm}0.67$ mm in the first group and $0.6{\pm}0.51$ mm in the second group, after 12 month. Mean marginal bone loss showed no significant differences between two groups. CONCLUSION. This preliminary one-year result indicated that mandibular overdentures anchored to a single implant can be a safe and cost-effective method as a starting step for implant-overdenture treatment.

• The korean journal of orthodontics
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• v.45 no.4
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• pp.164-170
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• 2015

Objective: The aim of this study was to compare the shear bond strength (SBS) of orthodontic brackets bonded to zirconia surfaces using three different zirconia primers and one silane primer, and subjected to thermocycling. Methods: We designed 10 experimental groups following the surface treatment and thermocycling. The surface was treated with one of the following method: no-primer (NP), Porcelain Conditioner (PC), Z-PRIME Plus (ZP), Monobond Plus (MP) and Zirconia Liner Premium (ZL) (n=20). Then each group was subdivided to non-thermocycled and thermocycled groups (NPT, PC, ZPT, MPT, ZLT) (n=10). Orthodontic brackets were bonded to the specimens using $Transbond^{TM}$ XT Paste and light cured for 15 s at $1,100mW/cm^2$. The SBS was measured at a 1 mm/min crosshead speed. The failure mode was assessed by examination with a stereomicroscope and the amount of bonding resin remaining on the zirconia surface was scored using the modified adhesive remnant index (ARI). Results: The SBS of all experimental groups decreased after thermocycling. Before thermocycling, the SBS was ZL, $ZP{\geq}MP{\geq}PC>NP$ but after thermocycling, the SBS was $ZLT{\geq}MPT{\geq}ZPT>PCT=NPT$ (p > 0.05). For the ARI score, both of the groups lacking primer (NP and NPT) displayed adhesive failure modes, but the groups with zirconia primers (ZP, ZPT, MP, MPT, ZL, and ZLT) were associated with mixed failure modes. Conclusions: Surface treatment with a zirconia primer increases the SBS relative to no-primer or silane primer application between orthodontic brackets and zirconia prostheses.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.4
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• pp.419-430
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• 2007

Purpose: This in vitro study evaluated shear bond strengths of surface treatment porcelains with four porcelain repair systems simulating intraoral bonding of composite resin to feldspathic porcelain or pressable porcelain. Material and methods: Eighty Porcelain disks were prepared. Group A: forty disk specimens were fabricated with Feldspathic Porcelain($Omega^{(R)}900$, Vident, Menlo Park, CA, USA). Group B: forty disk specimens were fabricated with Pressable Porcelain(IPS Empress 2 ingot, Ivoclar-Vivadent, Schaan, Liechtenstein, Germany). Each groups was divided into 4 subgroups and composite resin cylinders were bonded to specimen with one of the following four systems: Clearfil Porcelain Bond(L. Morita, Tustin, CA, USA), Ulradent Porcelain Etch. (Ultradent, Salt Lake City UT, USA), Porcelain Liner-M(Sun Medical Co., Kyoto, Japan), Cimara Kit(Voco, Germany). After surface conditioning with one of the four porcelain repair systems substrate surfaces of the specimen were examined microscopically(SEM). Shear bond strengths of specimens for each subgroup were determined with a universal testing machine (5mm/min crosshead speed) after storing them in distilled water at $37{\pm}1^{\circ}C$ for 24 hours. Stress at failure was measured in $MP_a$, and mode of failure was recorded. Differences among four repair systems were analyzed with two way ANOVA and Duncan test at the 95% significance level. Results: In the scanning electron photomicrograph of the treated porcelain surface, hydrofluoric acid etched group appeared the highest roughness. The shear bond strength of the phosphoric acid etched group was not significantly(p>0.05) different between feldspathic porcelain and pressable porcelain. But in no treatment and roughened with a bur group, the shear bond strength of the feldspathic porcelain was significantly higher than that of the pressable porcelain. In hydrofluoric acid etched group, the shear bond strength of the pressable porcelain was significantly higher(p<0.05). Conclusion: 1. Treatment groups showed significantly greater shear bond strengths than no treatment group(p<0.05). 2. Group with more roughened porcelain surface did not always show higher shear bond strengths. 3. In phosphoric acid etched group, there was no significant difference in shear bond strength between feldspathic porcelain and pressable porcelain(p>0.05). However in the other groups, there were significant differences in shear bond strengths between feldspathic porcelain and pressable porcelain(p<0.05).

• The Journal of Korean Academy of Prosthodontics
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• v.32 no.2
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• pp.268-280
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• 1994

Tissue conditioners have been used for treatment of denture stomatitis caused by wearing of dentures. Early studies pointed out Candide albicans (C. albicans) as main etiologic factor, and antifugal agents were added for control of the species. But there is a little information about broad comparison on the effect of tissue conditioners and antifungal agents added. The purpose of the present study was to compare the inhibiting effect of four tissue conditioners and one temporary soft liner on the growth of C. albicans for treatment of denture stomatitis using gel diffusion method by measuring diameter of the zone of growth inhibition. Three antifungal agents were added to each material for evaluation of the effect of added agents. Finally, observation was made to evaluate the effect of the loss of antifungal elements by aging of the specimen. The results of this study were obtained as follows : 1. Tempo had remarkable antifungal effect showing the zone of growth inhibition as 2.35 mm at 1st day, and was most effective on End: 4th and 7th day from incubation (p<0.05). But Coecomfort, Dura conditioner, Visco-gel, Coe-soft had little antifungal effect from the 1st day of incubation. 2. Nystatin was most effective showing 9.60-12.04 mm of zone of inhibition at the 1st day from incubation. The antifungal properties were reduced to amphotericin B, chlorhexidine and materials without agent (p<0.05), and the effect was diminished by time. 3. As pretreatment with amphotericin B, nystatin, chlorhexidine, Tempo was very effective at the 1st day from incubation showing zone of inhibition as 3.65, 12.04, 4.78 mm with addition of each agent. Dura conditioner had strongest antifungal effect at the next day as 2.86, 5.33, 1.29 mm of zone of inhibition, and yielding results of Coe-comfort, Tempo, Coe-soft was shown at 4th and 7th day from incubation (p<0.05). Taken all together, tissue conditioners have little antifungal effect except Tempo. Formation of the zone of growth inhibition was due to agents amphotericin B, nystatin, chlorhexidine and nystatin was most effective. Conclusively, it is advisable to select material which is effective on the growth of C. albican and consider addition of antifungal agents for treatment of denture stomatitis.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.4
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• pp.616-622
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• 1999

The primary objective of pulp treatment is to maintain the integrity and health of the oral tissues. The most important and difficult aspect of pulp therapy is determining the health of the pulp, or its stage of inflammation, so that a decision can be made regarding the best form of treatment. Immature permanent teeth are good candidates for many pulp healing procedures, due to their rich blood supply, which is believed to enhance the pulp's ability to react successfully to various insults. Healing was considered to have taken place when the tooth fulfilled the following criteria: 1. Abscence of clinical symtoms 2. Radiographic evidence of dentin bridge formation 3. No intrapulpal or periapical pathosis was evident radiographically 4. Continued root development and closure of the apex in immature teeth 5. Normal dentin apposition in mature teeth 6. Positive response to electrical pulp test This presents a report of cases in which immature permanent teeth, pulp-exposed by caries or trauma, was treated successfully by partial pulpotomy.

• The Journal of Advanced Prosthodontics
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• v.5 no.3
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• pp.270-277
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• 2013

PURPOSE. This study was aimed to determine the effect of two chemically distinct denture cleansers and water on the surface hardness of acrylic and silicone based soft denture liners at various time intervals. MATERIALS AND METHODS. Two commonly used commercial resilient liner material were selected based on their chemical composition (silicone- and acrylic-based soft liners) for this investigation. 120 cylindrical specimens were made of $15mm{\times}10mm$ dimensions (according to ASTM: D-2240-64T) in a custom made metal mold. All specimens were stored in artificial saliva throughout the study. Forty specimens were cleansed daily in 0.5% sodium hypochlorite solution; forty were cleansed in sodium perborate and remaining forty specimens were daily rinsed in water. Testing was done at 1 week, 1 month, 3 months and 6 months for surface hardness using a Shore A Durometer. A mean of 3 reading for each sample was subjected to one-way ANOVA, Post Hoc test and pair-t test for statistical analysis. P values of less than 0.05 were taken as statistically significant. RESULTS. Surface hardness of all the samples was significantly higher after a period of 6 months irrespective of the cleansing treatment. Minor changes were observed between control, sodium hypochlorite and sodium perborate groups with time. Greater change was observed in surface hardness of acrylic-based soft denture liners as compared to silicone-based soft liners for all groups, as time progressed. CONCLUSION. Silicone-based soft denture liners performed significantly better in all cleansing treatments than acrylic-based soft denture liners.