• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.316-327
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• 1998

This study was designed to examine the tissue levels of interleukin-$1{\alpha}$(IL-$1{\alpha}$), interleukin-$1{\beta}$(IL-$1{\beta}$) and tumor necrosis factor-${\alpha}$(TNF-${\alpha}$) in inflamed human dental pulps and periapical lesions, and to determine the relationship between each cytokine and pulpal and periapical pathosis. The pulps used in this experiment, were obtained in routine endodontic treatment and the periapical lesions in periapical surgery after clinical diagnoses were performed. These specimens were divided into four groups as normal pulp group(control group, n=9), acute pulpitis group(n=g), chronic pulpitis group(n= 10) and periapical lesion group(n= 18) and stored in liquid N2. For extract preparation, tissues were finely minced with a scalpel, and the fragments were incubated in $0.5m\ell$ homogenizing buffer (0.1 mol/L potassium chloride, 0.02 mol/L TRIS; pH=7.6) for two hours and grinded with glass homogenizer. Debris was removed by centrifugation and supernatants were immediately tested with enzymelinked immunosorbent assay (ELISA, R&D Co., Minneapolis, USA). Following results were obtained; 1. The concentrations of IL-$1{\alpha}$ in all experimental groups were significantly higher than in control group(p<0.05). And the concentrations of IL-$1{\alpha}$ in periapical lesion group were somewhat higher than in two pulpitis groups, but the differences among those groups were not stastically significant (p>0.05). 2. The concentrations of IL-$1{\beta}$ in all experimental groups were significantly higher than in control group (p<0.05), and all the experimental groups expressed similar concentrations. 3. The concentrations of TNF-${\alpha}$ in all experimental groups were higher than in control group but only the differences between chronic pulpitis group and control group were statistically significant(p<0.05). And the concentrations of TNF-${\alpha}$ in acute and chronic pulpit is groups were higher than in periapical lesion group but only the differences between chronic pulpitis group and periapical lesion group were statistically significant (p<0.05). 4. There was significant correlation only between IL-$1{\alpha}$ and IL-$1{\beta}$ in periapical lesion group (p<0.05).

• Nuclear Engineering and Technology
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• v.55 no.10
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• pp.3787-3800
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• 2023

Reactivity Initiated Accident (RIA) scenarios require special attention using advanced simulation techniques due to their complexity and importance for nuclear power plant (NPP) safety. While the conservative approach has traditionally been used for safety analysis, it may lead to unrealistic results which calls for the use of best estimate plus uncertainty (BEPU) approach, especially with the current advances in computational power which makes the BEPU analysis feasible. In this work an Uncontrolled Control Element Assembly (CEA) Withdrawal at Full Power accident scenario is analyzed using the BEPU approach by loosely coupling the thermal hydraulics best-estimate system code (RELAP5/SCDAPSIM/MOD3.4) to the statistical analysis software (DAKOTA) using a Python interface. Results from the BEPU analysis indicate that a realistic treatment of the accident scenario yields a larger safety margin and is therefore encouraged for accident analysis as it may enable more economic and flexible operation.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.7
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• pp.496-501
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• 2016

This paper presents a design method of non-parallel distributed compensation (non-PDC) static output feedback controller for continuous- and discrete-time T-S fuzzy systems. The existence condition of static output feedback control law is represented in terms of linear matrix inequalities (LMIs). The proposed sufficient stabilizing condition does not need any transformation matrices and equality constraints and is less conservative than the previous result of [21].

• Restorative Dentistry and Endodontics
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• v.24 no.2
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• pp.392-398
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• 1999

The purpose of this study was to assess the effect of catalase used following bleaching for the elimination of hydrogen peroxide residues from human teeth on the microleakage at the tooth-resin composite interface. In this study, class V cavities were prepared on the buccal or lingual surfaces of seventy extracted human molar teeth, and crown of sixty teeth were immersed in 30% hydrogen peroxide at $37^{\circ}C$ for 5 days except for negative control group. Then the teeth were rinsed with water and distributed randomly into seven groups of 10 each and were conditioned as following Negative control group: No bleaching Positive control group : bleaching and no application of catalase (C-40) Experimental group 1 : one cycle of catalase application for 3 min. and water rinse for 2 min. after bleaching Experimental group 2 : two cycles of catalase application for 3 min. and water rinse for 2 min. after bleaching Experimental group 3 : three cycles of catalase application for 3 min. and water rinse for 2 min. after bleaching Experimental group 4 : four cycles of catalase application for 3 min. and water rinse for 2 min. after bleaching Experimental group 5 : five cycles of catalase application for 3 min. and water rinse for 2 min. after bleaching The cavities of each groups were restored with composite resin. The teeth were thermocycled, stained with 2% methylene blue, and sectioned buccolingually. Degree of dye penetration at tooth-restoration interfaces were examined by stereomicroscope(${\times}30$) at occlusal and gingival margin The results were as follows : 1. On the occlusal margin, there was no significant difference in the microleakage between the negative coltrol group and experimental groups (p>0.05). But on the gingival margin, experimental groups showed higher microleakage than the negative coltrol group (p<0.05). 2. On the occlusal margin, positive coltrol group showed higher microleakage than experimental groups (p<0.05) and among the experimental groups, group 1 showed higher microleakage than group 3, 4, 5 (p<0.05). 3. On the gingival margin, there was no significant difference between the positive coltrol group and experimental groups, and between experimental groups (p>0.05). The result indicated that catalase used in bleached cavity for the elimination of hydrogen peroxide residues from human teeth maybe reduced microleakage at the tooth-resin composite interface.

• Korean Journal of Dental Materials
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• v.46 no.1
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• pp.1-10
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• 2019

There are several causes of tooth discoloration following root canal treatment. In this study, we evaluated the effects of sealers on tooth discoloration and internal bleaching. Twenty-four teeth were divided into 4 groups: control group, AH plus, Endosequece BC, and MTA fillapex group. Root canal filling was performed using each sealer conventionally and non-vital bleaching was performed with sodium perborate. The L, a, and b values were measured using Vita easyshade. Tooth discoloration after root canal treatment occurs irrespective of the type of sealers and may cause discoloration with only gutta-percha cone. The effect of non-vital bleaching following the use of calcium silicate-based sealers such as Endosequece BC and MTA fillapex was higher than that of AH plus. Therefore, it needs careful use of sealers in endodontics and calcium silicate-based sealers have advantages of bleaching in case of discolored tooth.

• Restorative Dentistry and Endodontics
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• v.47 no.4
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• pp.40.1-40.18
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• 2022

Objectives: This study aimed to investigate the influence of different obturation techniques compared to cold lateral compaction on the success rate of primary non-surgical endodontic treatments. Materials and Methods: Systematic searches were performed for studies published up to May 17^th, 2022 in MEDLINE/PubMed, Cochrane Library, Web of Science, Scopus, EMBASE, and Grey Literature Reports. Randomized clinical trials and nonrandomized (nonrandomized clinical trials, prospective or retrospective) studies that evaluated the success rate of primary non-surgical endodontic treatments obturated with the cold lateral compaction (control) and other obturation techniques were included. The revised Cochrane risk of bias tools for randomized trials (RoB 2) and nonrandomized studies of interventions (ROBINS-I) were used to evaluate the risk of bias. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool was used to evaluate the certainty of evidence. Results: Eleven studies (4 randomized clinical trials (RCTs), 4 prospective, and 3 retrospectives) were included. Two RCTs were classified as having some concerns risk of bias and 2 as a low risk of bias. Two nonrandomized studies were classified as having a critical risk of bias and 5 as having a moderate risk of bias. The GRADE analysis demonstrated a very low to moderate certainty of evidence. Conclusions: This systematic review generally evidenced no differences in the success rate of primary non-surgical endodontic treatments when the cold lateral compaction technique and other obturation techniques are performed. Further well-designed studies are still necessary.

• Restorative Dentistry and Endodontics
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• v.22 no.2
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• pp.792-800
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• 1997

The purpose of this study was to evaluate the adaptation of self-cured glass ionomer cement and resin-modified glass ionomer cement and polyacid-modified resin composite, which are light-cured giass ionomer cements, to dentin surface. Twelve extracted human maxillary and mandibular molar teeth were used in this study. The entire occlusal dentin surfaces of teeth were exposed with Diamond Wheel Saw and smoothed with sand papers (300, 600, 1200grits). They were randomly assigned into 3 groups according to glass ionomer cements used; Control group- Fuji II, Expeimental group 1 - Fuji II LC, Expeimental group 2 - Dyract. According to the manufacturer's directions, three glass ionomer cements were bonded to exposed dentin surfaces of the tooth crown and cured. Crowns and glass ionomers were trimmed after 24hrs and sectioned horizontally and vertically with diamond saw. The interface of glass ionomer cements and dentin was examined under SEM. The results were as follows : 1. Good adatation between glass ionomer cement and dentin on the horizontal section was showed in control and experimental group 1, but the gap of $20{\mu}m$, which was observed distinct separation between glass ionomer cement and dentin, was showed in experimental group 2. 2. Good adatation between glass ionomer cements and dentin on the vertical section was showed in control and experimental group 1, but the gap of 80-$100{\mu}m$ was showed in experimental group 2. 3. Cohesive fracture within glass ionomer cements in control and experimental group 1 was showed, but no cohesive fracture was showed in experimental group 2.

• The Journal of the Korea Contents Association
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• v.9 no.11
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• pp.271-279
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• 2009

Frozen shoulder is clinically characterized by pain and reduced ROM. The therapeutic goal of frozen shoulder can be reducing pain and increasing ROM in shoulder joint, resulting in improvement of joint movement. Therefore, this study was conducted to know the effect of mobilization in parallel with conservative physical therapy(H/P, TENS, U/S) in patients with frozen shoulder on subjective pain scale and ROM. 26 patients diagnosed with frozen shoulder were included for study. Among them, 13 patients(experiment group) were managed by mobilization as well as conservative physical therapy, another 13 patients(control group) were only treated by conservative physical therapy alone. All the patients were treated three times a week for 4 weeks, and after each treatment subjective pain scale and ROM were measured. In experimental group, pain has decreased and ROM has increased in abduction, external rotation and internal rotation. In control group, pain has also decreased but ROM has not changed in abduction, external rotation and internal rotation. There were no significant difference in subjective pain scale between two groups but some difference in ROM (external rotation, internal rotation). According to the results, we concluded that both conservative physical therapy and joint mobilization technique are more effective for increasing ROM especially external rotation, internal rotation than conservative physical therapy alone.

• Restorative Dentistry and Endodontics
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• v.18 no.1
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• pp.1-26
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• 1993

The purpose of this study was to investigate the effect of acid etching on the surface appearance and fracture toughness of five glass ionomer cements. Five kinds of commercially available glass ionomer cements including chemical curing filling type, chemical curing lining type, chemical curing metal reinforced type, light curing tilling type and light curing lining type were used for this study. The specimens for SEM study were fabricated by treating each glass ionomer cement with either visible light curing or self curing after being inserted into a rubber mold (diameter 4mm, depth 1mm). Some of the specimens were etched with 37% phosphoric acid for 0, 15, 30, 60, go seconds, at 5 minutes, 1 hour and 1 day after mixing of powder and liquid. Unetched ones comprised the control group and the others were the experimental groups. The surface texture was examined by using scanning electron microscope at 20 kV. (S-2300, Hitachi Co., Japan). The specimens for fracture toughness were fabricated by curing of each glass ionomer cement previously inserted into a metal mold for the single edge notch specimen according to the ASTME399. They were subjected to a three-point bend test after etching for 0, 30, 60, and 90 seconds at 5 minutes-, 1 hour-and 1 day-lapse after the fabrication of the specimens. The plane strain fracture toughness ($K_{IC}$) was determined by three-point bend test which was conducted with cross-head speed of 0.5 mm/min using Instron universal testing machine (Model No. 1122) following seven days storage of the etched specimens under $37^{\circ}C$, 100% humidity condition. Following conclusions were drawn. 1. In unetched control group, crack was present, but the surface was generally smooth. 2. Deterioration of the surface appearance such as serious dissolving of gel matrix and loss of glass particles occured as the etching time was increased beyond 15 s following Immediate etching of chemical curing type of glass ionomer cements. 3. Etching after 1 h, and 1 d reduced surface damage, 15 s, and 30s etch gave rough surface appearance without loss of glass particle of chemical curing type of glass ionomer cements. 4. Light curing type glass ionomer cement was etched by acid, but there was no difference in surface appearances according to various waiting periods. 5. It was found that the value of plane stram fracture toughness of glass ionomer cements was highest in the light curing filling type as $1.79\;MNm^{-1.5}$ followed by the light curing lining type, chemical curing metal reinforced type, chemical curing filling type and chemical curing lining type. 6. The value of plane stram fracture toughness of the chemical curing lining type glass ionomer cement etched after 5 minutes was lower than those of the cement etched after 1 hour or day or unetched (P < 0.05). 7. Light curing glass ionomer cement showed Irregular fractured surface and chemical curing cement showed smooth fractured surface.

• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.197-212
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• 1998

The purpose of this study was to evaluate the effects of fluoride application on the aspect of shear bond strength of three aesthetic restorative materials to dentin. One light-cured composite resin(Palfique Esterite) and two light-cured glass ionomer cements(Fuji II LC and Compoglass)were used in this study. 120 permanent molars were used for this study. The teeth were extracted due to the origin of periodontal disease. The crowns of all teeth were removed, and the remaining roots were embedded in epoxy resin. The mesial or distal surfaces of roots were ground flat to expose dentin and polished on wet 320-, 400-, and 600 grit SIC papers for a total of 120 prepared flat root dentin surfaces. The prepared samples were divided into six groups. Group 1, 3, and 5 were control groups and group 2, 4, and 6 were experimental groups. Sixty samples for experimental groups were treated with 2% NaF solution for 5 minutes. Group 1 and 2 were bonded with Plafique Esterite, group 3 and 4 were bonded with Fuji II LC, and group 5 and 6 were bonded with Compoglass. After 24 hours water storage at $37{\pm}1^{\circ}C$, all samples were subjected to a shear to fracture with Instron universal testing machine(No.4467) at 1.0 mm/min displacement rate. Dentin surfaces treated with each conditioners before bonding and interfacial layers between dentin and aesthetic restorative materials were observed under Scanning Electron Microscope(Hitachi S-2300) at 20Kvp. The data were evaluated statistically at the 95% confidence level with ANOVA test. The result were as follows; 1. Among the control groups, group 1 showed strongest bond strength and group 3 showed weakest. 2. Among the experimental groups, group 2 showed strongest bond strength and group 6 showed weakest. 3. Statistical analysis of the data showed that pretreatment of dentin with 2% NaF solution significantly decreased the bond strength of three aesthetic restorative materials to dentin(P<0.05). 4. SEM findings of fluoride treated dentin surfaces (2, 4, 6 group) demonstrated dentin surfaces covered with fluoridated reaction products. 5. Except group 4 and 6, resin tags were formed in all groups.