• Journal of the Korean Chemical Society
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• v.51 no.3
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• pp.291-297
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• 2007

• Journal of Periodontal and Implant Science
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• v.23 no.3
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• pp.647-658
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• 1993

The purpose of this study is to examine the influence of 5% tetracycline(Tc) gel on healing of gingival tissue and change of diseased root surface when used with nonsurgical procedure. 7 patients with advanced periodontitis were received thorough scaling and root planning, followed by saline irrigation on 10 randomly selected control teeth and Tc gel application for 5 minutes with specifically designed plastic instrument of 10 test teeth in contralateral side. At 0, 1, 7, 14, and 21 days after treatment, biopsy and extraction were carried out. At day 7, Tc group showed decreased inflammation and delayed proliferation of pocket epithelium in comparison with control group which was continued for all experimental days. Scanning electron microscopic finding revealed demineralized and cleaned root surface with exposed dentinal tubules in Tc gel group. In the present study, clinically successful result is expected with combined use of nonsurgical periodontal therapy and intrapocket application of Tc gel.

• Journal of Periodontal and Implant Science
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• v.24 no.1
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• pp.87-97
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• 1994

The ultimate goal of periodontal therapy is to fully reconstruct the periodontal attachment apparatus. Commonly used techniques for treatment of infrabony defects include a combination of root planing, curettage and root treatment. To prevent the apical migration of epithelial cells, the technique of guided tissue regeneration is used. The aim of this study is to compare the effects of root treatment with Citric acid & Tetracycline and Guided tissue regeneration in dogs. Experimental periodontitis was induced by the ligation of orthodontic elastic threads in the upper right and left premolars 3, 4 of five adult dogs for 6 weeks. 4 types of procedures were performed as follows; 1) Control graup : Mucoperiosteal flap 2) Experinental I : GTR used Gore-tex(R) membrane 3) Experinental II : Root treatment with citric acid (PHl) 4) Experinental III : Root treatment with tetracycline HCl (50mg/ml) There after, dogs were serially sacrificed at the 1, 2, 4, 5, 8 weeks, and the specimens were prepared, and stained with hematoxylin-eosin for the light microscopic evaluation. The results of this study were as follows; 1. Junctional epithelium reached to the notch through the furcation area in control group at 8 weeks. 2. In the aspects of the inflammatory cell infiltration, control group showed severe aggregation than experimental group I, II, III through the experimental period 3. New cementum was observed over the notch from 5 weeks in experimental group II 4. In the aspects of the amount of new bone formation, experimental group was better than control group, but there was not significant differences among the experimental group, I, II, III

• Journal of Oral Medicine and Pain
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• v.22 no.2
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• pp.309-325
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• 1997

In order to set the lasing variables and evaluate, clinically, the therapeutic effects of a pulsed Nd:YAG laser on oral lesion, the author applied the laser energy from a fiberoptic delivered, free running, pulsed Nd:YAG laser (wavelength 1064nm, Pulse duration 120$\mu$sec, fiber diameter 200$\mu$m/320$\mu$m) to 22 cases of oral soft tissue lesions and 6 cases of oral hard tissue lesions. The obtained results were as follows : 1. The effective excision with contact mode and the effective hemostasis of accompanied bleeding with noncontact mode were occurred by lasing on oral soft tissue lesions with fiber diameter of 320$\mu$m under the variables of 2.0~4.0W and 20~50Hz which were controlled into high power/low pulses for excision, low power/high pulses for hemostasis, low power in granulation tissue and high power in fibrous tissue according to therapeutic goals and tissue conditions. 2. About 50% of decreasing effect on hypersensitivity was occurred by lasing with non-contact and contact mode on cervical abrasion which caused dentinal hypersensitivity with fiber diameter of 320$\mu$m under the variables of 0.7 - 1.0W and 10Hz which were applied 2~3 times with 1 week interval. 3. The effective sterilization of infected root canal and lesion of periapical abscess was occurred by lasing with contact and spiral modes on wall of root canal and periapical abscess with fiber diameter of 200$\mu$m of which the tip was placed about 1mm shorter than root canal length under the variables of 1.OW and 10Hz.

• Journal of Ecology and Environment
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• v.30 no.3
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• pp.271-276
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• 2007

A simple and efficient protocol was developed for culturing Cu-tolerant and Cu-accumulating plants via pre-adaptation to Cu during plant tissue culture. We induced multiple shoots from begonia (Begonia evansiana Andr.) leaf explants on MS medium supplemented with naphtaieneacetic acid and benzyladenine. After 3 months, small plantlets were transferred to MS medium supplemented with $100{\mu}M\;CuCl_2$ for pre-adaptation to Cu and cultured for 5 months. Then, these plantlets were individually planted in pots containing artificial soil. An additional 500 mg of Cu dissolved in 1/4 strength MS solution was applied to each pot during irrigation over the course of 2 months. We planted pre-adapted and control begonias in soil from the II-Kwang Mine, an abandoned Cu mine in Pusan, Korea, to examine their ability to tolerate and accumulate Cu for phytore-mediation. Pre-adapted begonias accumulated $1,200{\mu}g$ Cu/g dry root tissue over the course of 45 days. On the other hand, non-Cu-adapted controls accumulated only $85{\mu}g$ Cu/g dry root tissue. To enhance Cu extraction, chelating agents, ethylenediamine tetraacetic acid (EDTA)-dipotassiun and pyridine-2,6-dicarboxylic acid (PDA), were applied. While the chelating agents did not enhance accumulation of Cu in the roots of control begonias, EDTA application increased the level of Cu in the roots of pre-adapted begonias twofold (to $2,500{\mu}g$ Cu/g dry root tissue). Because pre-adapted begonias accumulated a large amount of Cu, mainly in their roots, they could be used for phytostabilization of Cu-contaminated soils. In addition, as a flowering plant, begonias can be used to create aesthetically pleasing remediation sites.

• Restorative Dentistry and Endodontics
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• v.19 no.2
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• pp.549-567
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• 1994

Restoration of severly damaged teeth after endodontic treatment had been an interest to many dentists, and it is a fact that there have been lots of studies about it. In these days, although we have used Para-Post, pins, threaded steel post, cast gold post and core, and so on, as a method of restoration frequently, it has been in controversy with the influence of them on the teeth and surrounding periodontal tissue. In this study, we assume that the crown of the upper incisor have severly damaged, so, after the root canal therapy, 4 types of restoration had been carried out; 1) coronal-radicular amalgam restoration, 2) after setting up the Para-Post, restore with composite resin core only, 3) after setting up the Para-Post; restore with amalgam core, then cover with the PPM crown 4) after setting up the Para-Post, restore with composite core, then cover with the PPM crown. After restoration, in order to observe the concentration of stress at internal portion of the teeth and the sourrounding periodontal tissue, developing a 2-dimensional finite element model of labiopalatal section, then loading forces from 3 direction - direction of 45 degrees from lingual side near the incisal edge, horizontal direction from labial height of contour, vertical direction at the incisal edge-were applied. The analyzed results were as follows: 1. Stress of the normal central incisor was concentrated on the dentin aroundpulp chamber, labiocervical portion of a tooth and root apex, but with the alveolar bone, in the case of load from the direction of 45 degrees from lingual side near the incisal edge showed remarkable concentration of stress: 2. Coronal-radicular amalgam technique -showed less concentration of stress on the root and surrounding periodontal tissue than the restoration with the Para-Post. 3. The von Mises equivalent stress on the Para-Post showed maximum value at root-core junction rather than both ends and model with PPM restoration with amalgam core showed the least concentration of stress. Only the force from horizontal direction showed large shear stress on internal portion of the root, root apex and alveolar bone. 4. PPM crown with composite core rarely showed the concentration of stress on root and periodontal tissue. 5. As for alveolar bone, remarkable shear stress was concentrated on labial and palatal side by horizontal load.

• Proceedings of the KACD Conference
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• 2002.11a
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• pp.720-720
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• 2002

A number of investigations have shown that the presence of bacteria is prerequisite for developing pulpal and/or periradicular pathosis. Depending on the stage of pulpal pathosis, various species of bacteria can be cultured from infected root canals. Kakehashi et al. showed that exposure of pulpal tissue in germ-free rats was characterized by minimal inflammation and dentinal bridging while exposure of pulpal tissue in conventional rats with normal oral flora was characterized by pulpal necrosis, chronic inflammation, and periapical lesions. Currently used methods of cleaning and shaping, especially rotary instrumentation techniques, produce a smear layer that covers root canal walls and the openings to the dentinal tubules. The smear layer contains inorganic and organic substances that include fragments of odontoblastic processes, microorganisms, their by products and necrotic materials. Because of its potential contamination and adverse effect on the outcome of root canal therapy, it seems reasonable to suggest removal of the smear layer for disinfection of the entire root canal system. Presence of this smear layer prevents penetration of intracanal medications into the irregularities of the root canal system and the dentinal tubules and also prevents complete adaptation of obturation materials to the prepared root canal surfaces. Removal of the smear layer by an intracanal irrigant and placement of an antibacterial agent in direct contact with the content of dentinal tubules should allow disinfection of this complex system and better outcome for the root canal therapy. A new solution, which was a mixture of a tetracycline, an acid, and a detergent(MTAD), was developed in the Department of Endodontics, Dental School. Lorna Linda University, USA. It has been demonstrated that MTAD was an effective solution for the removal of the smear layer and does not significantly change the structure of the dentinal tubules when used as a final irrigant in conjunction with 1 % NaOCl as a root canal irrigant. Studies are in progress to compare the anti- microbial properties of this newly developed solution with those of sodium hypochlorite and EDTA that are currently used to irrigate the root canals and remove the smear layer from the surfaces of instrumented root canals.canals.

• Journal of Periodontal and Implant Science
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• v.29 no.4
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• pp.861-872
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• 1999

Since pathologic changes of exposed root surface inhibit cell attachment and new attachment of connective tissue have been made, many efforts were apply to change the exposed root surface condition. Scaling and root planing can not remove the endotoxin completely and forms the smear layer which prohibits the new attachment of connective tissue. Therefore, many kinds of chemicals were used for controlling the pathologic change of the root surface. The purposes of this study was to compare and observe the changes of the exposed root surface treated by scaling and root planning, Tetracycline HCl and Argon Laser. After the scaling and root planning of ten extracted premolars, the differences & the root surface among groups were observed under SEM. Control group showed smear layer and irregular amorphous surface. The dentinal tubule was not exposed. The debris and scale like texture were also observed. Tetracycline HCl treated group showed relatively smooth surface and the collagen fiber was observed in the dentinal tubule. Argon Laser treated group showed the most effective results under the conditions of 0.8 to 1.0w irradiation for 0.5 to 1.0 sec with pulse wave. The results of this study showed that the root surface change was associated with the intensity and the duration of Argon Laser irradiation. Further investigation for the surface change with the Argon Laser irradiation is recommended for understanding of clinical effect.

• Journal of Periodontal and Implant Science
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• v.45 no.4
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• pp.152-155
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• 2015

Purpose: This case report discusses the effect of a root submergence technique on preserving the periodontal tissue at the pontic site of fixed dental prostheses in the maxillary anterior aesthetic zone. Methods: Teeth with less than ideal structural support for fixed retainer abutments were decoronated at the crestal bone level. After soft tissue closure, the final fixed dental prostheses were placed with the pontics over the submerged root area. Radiographic and clinical observations at the pontic sites were documented. Results: The submerged roots at the pontic sites preserved the surrounding periodontium without any periapical pathology. The gingival contour at the pontic site was maintained in harmony with those of the adjacent teeth, as well as the overall form of the arch. Conclusions: The results of this clinical report indicate that a root submergence technique can be successfully applied in pontic site development with fixed dental prostheses, especially in the maxillary anterior esthetic zone.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.s01
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• pp.115-123
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• 1988

Ginseng has been used as a medicinal herb in the world for more than two thousand years. Inspection of the quality of ginseng was made since many hundred years ago. Ginseng quality has been graded by several methodes, based on saponin contents, number of ginsenosides, shape of root and tissue elaborateness. In present. ginseng products are usually evaluated by saponin contents and number of ginsenosides. On the other hand, fresh and manufactured ginseng roots such as red. white and semi-red ginseng, Taegeuk Sam, are mostly graded by root shape such as root development and skin (epidermis) color, and tissue elaborateness. which is a conventional grading method. However, the root shape grading method has a risk of overlooking real medicinal properties of ginseng. So. both the medicinal ingredients and the conventional grading method should be considered for the proper evaluation of ginseng quality. Therefore, for the establishment of better method in evaluating ginseng quality, the relationships of root shape and useful components are required to be studied.