• Journal of Periodontal and Implant Science
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• v.52 no.1
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• pp.54-64
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• 2022

Purpose: This in vitro study was conducted to evaluate the effects of different debridement techniques and conditioning procedures on root surface morphology and blood clot stabilization. Methods: Two debridement techniques (curette [CU] vs. high-speed ultrasound [US]) and 2 conditioning procedures (ethylenediaminetetraacetic acid [EDTA] and phosphoric acid [PA]) were used for the study. Seven experimental groups were tested on root surfaces: 1) no treatment (C); 2) CU; 3) US; 4) CU+EDTA; 5) US+EDTA; 6) CU+PA; and 7) US+PA. Three specimens per group were observed under scanning electron microscopy (SEM) for surface characterization. Additional root slices received a blood drop, and clot formation was graded according to the blood element adhesion index by a single operator. Data were statistically analyzed, using a threshold of P<0.05 for statistical significance. Results: The C group displayed the most irregular surface among the tested groups with the complete absence of blood traces. The highest frequency of blood component adhesion was shown in the CU+EDTA group (P<0.05), while no differences were detected between the CU, US+EDTA, and CU+PA groups (P<0.05), which performed better than the US and US+PA groups (P<0.05). Conclusions: In this SEM analysis, EDTA and conventional manual scaling were the most efficient procedures for enhancing smear layer removal, collagen fiber exposure, and clot stabilization on the root surface. This technique is imperative in periodontal healing and regenerative procedures.

• Restorative Dentistry and Endodontics
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• v.40 no.1
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• pp.75-78
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• 2015

Presented here is a case where 8 canals were located in a mandibular first molar. A patient with continuing pain in mandibular left first molar even after completion of biomechanical preparation was referred by a dentist. Following basic laws of the pulp chamber floor anatomy, 8 canals were located in three steps with 4 canals in each root. In both of the roots, 4 separate canals commenced which joined into two canals and exited as two separate foramina. At 6 mon follow-up visit, the tooth was found to be asymptomatic and revealed normal radiographic periapical area. The case stresses on the fact that understanding the laws of pulp chamber anatomy and complying with them while attempting to locate additional canals can prevent missing canals.

• Journal of Periodontal and Implant Science
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• v.27 no.3
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• pp.495-514
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• 1997

The purpose of this study was to evaluate the in vitro effects of Nd:YAG laser irradiation on removal of a root surface smear layer after root planing in comparison with Tetracycline HCl. The 60 extracted human teeth due to severe periodontal disease were vigorously scaled and root planed with Gracey curet. Thirty specimen($5{\times}5{\times}2mm$) were obtained from root planed surface of 30 human teeth and assigned randomly to one of three groups : root planed group(5 specimen), Tetracycline HCI group(5 specimen, burnished for 5 minutes), and Nd:YAG laser group(25 specimen, German Dental Laser, Fotona Twinlight). Nd:YAG laser group was divided into 4 subgroups according to power of 1W, 1.5W, 2W, 3W at frequency to 10Hz. The specimen were then fixed, and examed by Scanning electron microscopic study. 30 of 60 human teeth used to measurement of the intrapulpal temperature rise during laser irradiation. Laser-irradiated surface exhibited various surface texture from relative flat surface to irregular surface with patent dentinal tubules of various shape and size. In some area, the root surface alteration which are carbonization, pit and crater formation and melting and resolidification were observed. The number of exposed dentinal tubules per unit($100_{\mu}m^2$) on tetracycline HCI group was more than that in the laser group below 1.5W of power(150mJ/pulse) and was significantly less than that in laser group above 2W of power(200mJ/pulse)(P<0.OOl). As power increased the intrapulpal temperature rise also increased. The result suggested that the parameter which effectively remove root surface smear layer than tetracycline HCI may cause thermal damage to pulp and root surface alteration result from laser exposure would indicate need for additional instrumentation. Thus, Nd:YAG laser irradiation in these parameter may not be appropriate for clinical use as adjunct to conventional periodontal therapy.

• The Journal of the Korean dental association
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• v.51 no.10
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• pp.556-564
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• 2013

Modern endodontics has essentially changed following the introduction of the dental microscope since 1990's. One of main advantage of using dental microscope in nonsurgical endodontic treatment is enhancing clinician's ability and quality of treatment through illumination and magnification. Scopes of dental microscope in nonsurgical endodontics are finding a missed or additional root canal and a tooth crack, management of procedural errors, and others. These improvements in technology will result in greater confidence in treatment and better success in clinical practice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.3
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• pp.298-305
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• 1984

The competitive relationship between orchardgrass (Dactylis glomerata L.) and ladino clover (Trifolium repens L.) was studied under aerial and soil partitions and N, P fertilizer combinations. Orchardgrass and ladino clover were grown in field with one of non competition, shoot competition only, root competition only, full competition and competition between same species. Under basal application of K fertilizer N and P were applied in treatment combinations of blank, N only (l5kg/10a), P only (l5kg/10a), and both NP at planting and each cutting. The forage yield in mixture was between yield of pure orchard grass stand and the 'expected yield', which was a mean of both pure stands. The forage yield in pure ladino was the lowest. During the experiment there was a progressive decline in clover yield either pure stand or mixture. Since orchardgrass was 'over-compensated' to low-yielding clover, the yield of mixture was more than non competition. Orchard grass was more competitive than ladino clover as seasons advanced. The aggressivity of orchardgrass was higher in root competition than in shoot competition comparing to clover. Nitrogen fertilizer increased orchardgrass yield, while phosphate did ladino clover yield and root weight of both species. But the additional effect of P to N was not significant in dry weight and LAI.

• Restorative Dentistry and Endodontics
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• v.29 no.6
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• pp.541-547
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• 2004

The aim of this study was to compare the initial apical file (IAF) length between the mesio-buccanl and mesio-lingual canals of the mandibular molar before and after early coronal flaring. Fifty mandibular molars with complete apical formation and patent foramens were selected. After establishing the initial working length of the buccal and lingual canal of the mesial root using the Root-ZX, radiographs were taken for the working length with a 0.5 mm short of #15 K-file tip just visible at the foramen under a surgical microscope (OPMI 1-FC, Carl Zeiss Co. Germany) at 25X. After early coronal flaring using the $K^3$ file, additional radiographs were taken using the same procedure. The root canal morphology and the difference in working length between the buccal and lingual canals were evaluated. These results show that the difference in the length between the mesio-buccal and mesio-lingual canals of the mandibular molar was $\leq$ 0.5 mm. If one canal has a correct working length for the mesial root of the mandibular molar, it can be used effectively for measuring the working length of another canal when the files are superimposed or loosening. In addition, the measured the working length after early coronal flaring is much more reasonable because the difference in the length between the mesio-buccal and mesio-lingual canals can be reduced.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.154-154
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• 2019

Characterization of reliable field-scale root-zone soil moisture (RZSM) variability contribute to effective hydro-meterological monitoring. Although a promising cosmic-ray neutron probe (CRNP) holds the pontential for field-scale RZSM measurement, it is often restricted at deeper depths due to the non-unique sensitivity of CRNP-measured fast neutron signal to other hydrogen pools. In this study, a merging framework relied on coupling cosmic-ray soil moisture with a representative additional RZSM, was introduced to scale shallower CRNP effective depth to represent root-zone layer. We tested our proposed framework over a densely vegetated region in South Korea covering a network of one CRNP and nine in-situ point measurements. In particular, cosmic-ray soil moisture and ancillary RZSM retrieved from the most time stable location were considered as input datasets; whereas the remaining point locations were used to generate a reference RZSM product. The errors between these two input datasets and the reference were forecasted by a linear autoregressive model. A linear combination of forecasts was then employed to compute a suitable weight for merging two input products from the predicted errors. The performance of merging framework was evaluated against reference RZSM in comparison to the two original products and a commonly used exponential filter technique. The results of this study showed that merging framework outperformed other products, demonstrating its robustness in improving field-scale RZSM. Moreover, a strong relationship between the quality of input data and the performance merging framework in light of CRNP effective depth variation has been also underlined via the merging framework.

• The KIPS Transactions:PartC
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• v.10C no.6
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• pp.675-682
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• 2003

Attackers collect vulnerabilities of a target computer system to intrude into it. And using several attack methods, they acquire root privilege. They steal and alter information in the computer system, or destroy the computer sysem. So far many intrusion detection systems and firewallshave been developed, but recently attackers go round these systems and intrude into a computer system . In this paper, we propose security kernel module to prevent attackers having acquired root privilege from doing illegal behaviors. It enhances administrator authentication with additional password, so prevents attackers from doing illegal behaviors such as modification of important files and installation of rootkits. It sends warning mail about sttacker's illegal behaviors to administrators by real time. So using information in the mail, they can estabilish new security policies.

• Journal of Periodontal and Implant Science
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• v.35 no.1
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• pp.177-185
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• 2005

The purpose of the study was to investigate the influence of an endodontic infection on presence of furcation involvement in periodontally-involved mandibular molars. All first and second mandibualr molars in 45 patients were selected if at least one was root-filled or had a possible periapical radiolucency. The sample consisted of patients from a referral population at a periodotnal clinic which represented an adult population with a mean age of 47.5 years (range 31 to 63) For mandibular molars with periapical destruction at both roots, frequency of horizontal furcation depth ${\geqq}$ 3 mm was significantly more compared to teeth without periapical destruction. Mean periodontal probing depth was significantly greater at mandibular molars with periapical destruction. It is suggested that a root canal infection in periodontitis-involved molars may potentiate periodontitis progression by spreading of endodontic pathgens through patent accessory canals and dentinal tubules. In conclusion, an endodontic infection in mandibular molars was found to be associated with additional attachment loss in the furcation area, and may thus be considered to be one of several risk factors influencing the prognosis of molars in periodontitis-prone patients.

• Journal of Haehwa Medicine
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• v.10 no.1
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• pp.93-108
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• 2001

The purpose of this research was to investigate the effects of Sutaehwan(壽胎丸) for treatment Abortus habitualis(滑胎). I came to conculsion after considering literatures of every generation on the effects of Sutaehwan and then came to get some conclusion as follows. 1. Sutaehwan(壽胎丸) was designed to prescribe for treatment of Abortus habitualis(滑胎) 2. Sutaehwan(壽胎丸) was made use of Fetal Restlessness(胎動不安) caused by Kidney Deficiency(腎虛). 3. Sutaehwan(壽胎丸) was always used by the origin prescription itself, also used the modified prescription and the additional prescription. 4. Sutaehwan(壽胎丸) is the best quality prescription for treatment Abortus habitualis(滑胎) that due to Deficiency of Liver-Kidney Essence. Sutaehwan(壽胎丸) contains four specific herbs like Dodder Seed(兎絲子), Taxillus Twig(桑寄生), Himalayan Teasel Root(續斷), Donkey-hide Gelatin(阿膠). Dodder Seed(兎絲子) is effective the Tonifying Kidney, the Invigorating Yang and the Supplementing Essence. Taxillus Twig(桑寄生) is effective the Nourishing Blood and the Tonifying Kidney. Himalayan Teasel Root(續斷) is effective the Tonifying Liver-Kidney and the Regulation Blood. Donkey-hide Gelatin(阿膠) is effective the Tonifying Liver Blood, the Arresting Bleeding and the Supplementing Kidney Yin Fluid.