• Restorative Dentistry and Endodontics
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• 제27권5호
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• pp.543-551
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• 2002

Nitric oxide (NO) is a small molecule (mol. wt. 30 Da) and oxidative free radical. It is uncharged and can therefore diffuse freely within and between cells across membrane. Such characteristics make it a biologically important messenger in physiologic processes such as neurotransmission and the control of vascular tone. NO is also highly toxic and is known to acts as a mediator of cytotoxicity during host defense. NO is synthesized by nitric oxide synthase (NOS) through L-arginine/nitric oxide pathway which is a dioxygenation process. NO synthesis involves several participants, three co-substrates, five electrons, five co-factors and two prosthetic groups. Under normal condition, low levels of NO are synthesized by type I and III NOS for a short period of time and mediates many physiologic processes. Under condition of oxidant stress, high levels of NO are synthesized by type II NOS and inhibits a variety of metabolic processes and can also cause direct damage to DNA. Such interaction result in cytostasis, energy depletion and ultimately cell death. NO has the potential to interact with a variety of intercellular targets producing diverse array of metabolic effects. It is known that NO is involved in hemodynamic regulation, neurogenic inflammation, re-innervation, management of dentin hypersensitivity on teeth. Under basal condition of pulpal blood flow, NO provides constant vasodilator tone acting against sympathetic vasoconstriction. Substance P, a well known vasodilator, was reported to be mediated partly by NO, while calcitonin-gene related peptide has provided no evidence of its relation with NO. This review describes the roles of NO in dental pulp in addition to the known general roles of it.

• Restorative Dentistry and Endodontics
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• 제24권2호
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• pp.322-329
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• 1999

The hydrodynamic theory of dentin sensitivity states that movement of tubular contents or tubular fluid, in either direction of dentinal tubule, causes dentin sensitivity. A corollary of that theory is that anything that can decrease dentinal fluid movement or dentin permeability should decrease dentin sensitivity. A wide variety of physicochemical methods have been used to reduce the permeability and sensitivity of exposed dentin. The purpose of this study was to evaluate the ability of 4 kinds of clinical desensitizing agents(2% NaF, 30% Potassium oxalate, MS Coat$^{(R)}$, Tubulitec system$^{(R)}$) to reduce the rate of fluid flow through dentin in vitro. Sixty coronal dentin discs, 1mm in thickness, were prepared from extracted third molars, free from decay and wear. Dentin discs were treated with 3% EDTA(Tubulicid Plus$^{(R)}$(Dental Therapeutics AB, Sweden)) to remove the smear layer and debris occluding the tubular orifices. After placing the discs in a split chamber device, the rate at which physiologic saline solution could filter across dentin under 150cm $H_2O$ hydrostatic pressure was measured. The occlusal side of the discs were then treated with MS Coat$^{(R)}$, 2% NaF, Tubulitec system$^{(R)}$, and 30% Potassium oxalate, and the filter ratio of the saline solution was measured again. The following conclusions were drawn : 1. Hydraulic conductance which was measured after the application of desensitizing agents was decreased in all the groups(p<0.05). 2. % change of hydraulic conductance was compared but no significant difference was found among the four desensitizing agents(p>0.05). 2% NaF, 30% Potassium oxalate, MS Coat$^{(R)}$ and Tubulitec system$^{(R)}$ decreased the permeability of dentin. It is considered that above four agents can be used in treating the hypersensitive teeth.

• Restorative Dentistry and Endodontics
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• 제25권2호
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• pp.289-298
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• 2000

Carbamide peroxide is usually used for vital teeth bleaching at home. Complications such as tooth hypersensitivity and/or gingival irritation are frequently reported. Therefore, this study was performed to evaluate any possible histological changes in pulp and periodontal tissue by carbamide peroxide bleaching gel in rats. 10% and 15% carbamide peroxide containing nightguard for upper molar were worn for 4 hours a day. The rats were sacrificed after 1 day, 2 days, 3 days, 4 days and 6 days application of carbamide peroxide respectively. The results were as follows : Mild infiltration of inflammatory changes below the junctional epithelium and hyperplasia of epithelium were observed in both 10% and 15% carbamide peroxide treated groups. In all experimental groups, odontoblasts were changed from columnar to cuboidal shape and/or obliterated and the focal loss of predentin was observed in pulp horn. With increasing time of application, these changes were more remarkable, but limited in pulp horn. Inflammatory reactions, vacuolar changes and hyaline degenerations of the pup tissue were also observed in some cases. These results suggested that carbamide peroxide gel used in home bleaching could cause reversible pulpal irritation.

• 대한소아치과학회지
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• 제44권4호
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• pp.455-460
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• 2017

스티븐 존슨 증후군(Stevens-Johnson syndrome, SJS)은 피부와 점막에 광범위한 괴사를 초래하는 매우 심각한 급성 과민반응이다. SJS은 모든 연령대에서 발생할 수 있는 질환으로 원인은 명확하지는 않지만 대부분 약물 알레르기에 의한 것으로 알려져 있으며 그 외에도 세균감염에 의해 유발되기도 한다고 알려져 있다. 전체 표피면적의 10% 이하에서 병변이 발생한 경우를 SJS라 하며 30% 이상에서 발생한 경우를 독성 표피 괴사융해라 정의한다. SJS는 1년에 100만명 인구 당 1 - 2명 미만에서 드물게 발생하나, 성장기 어린아이에게 발생할 경우 치아발육 등에 미치는 영향을 미치게 된다. 6 - 7세경 상하악 제1대구치와 하악중절치의 맹출이 시작되고 이 시기에 치근의 발육이 함께 일어난다. 이 케이스의 환아의 경우 6세경 SJS이 발병하였다. 현재 완치된 상태이나 몇몇 후유증이 남아있는 상태이다. 환아는 이 시기에 발육이 완성되는 치아에 국한되어 발육이상이 관찰되었다. 구강내 특징으로 이러한 전신질환을 진단하고 이로 인한 치아 발육에 대한 영향에 대한 문제점을 인식하고 해결하고자 이 보고서를 쓰는 바이다.

• Journal of Periodontal and Implant Science
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• 제27권4호
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• pp.829-844
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• 1997

Dentin hypersensitivity must be one of the most frequent postoperative complaints in periodontal patients. Obliterating the open dentinal tubules or decreasing the diameter of their orifices would, therefore, be an objective of treatment for hypersensitive teeth. The purpose of this study was to evaluate the effect of a pulsed Nd:YAG laser irradiation on obliteration of dentinal tubules and to determine any difference according to irradiation methods. The 45 posterior teeth that had been extracted due to periodontal disease were initially treated with tetracycline HCI(100 mg/ml, 4 min.) to remove the smear layer after root planing. The root surfaces were then irradiated by a pulsed Nd:YAG laser(EL.EN.EN060, Italy) by different laser beam spot size and different exposure condition: ${\cdot}$ group 1: irradiated group by small spot(beam diameter=1mm, lW, 2 sec) ${\cdot}$ group 2: irradiated group by large spot(beam diameter=10mm, 1W, 200 sec) ${\cdot}$ group 3: irradiated group by gradual increase of watt (from 0.3W to 1.0W), beam diameter=4mm ${\cdot}$ group 4: irradiated group by fixed watt(1.0 W), beam diameter=4mm ${\cdot}$ control group: no irradiation but root planing and tetracycline HCI conditioning only. Additionally, the specimens were retreated with tetracycline HCI(100mg/ml, 4min.) to evaluate the stability of obliteration effect by Nd:YAG laser. Specimens were examined under the scanning electron microscope(JEOL, JSM-840A, Japan). Photomicrographs were taken at ${\times}4,000$ magnification and were analyzed statistically. The results were as follows: l. Scanning electron micrographs of root surface treated by tetracycline HCI alone(control group) showed widened, funnel-shaped dentinal tubules, while those of the root surface irradiated by various methods showed partially or completely obliterated dentinal tubules and various surface alterations, eg, flat, multiple pitted, melted and resolidified surface at the same energy density. 2. There was no significant difference in the obliteration effect of dentinal tubules between group 1 and group 2, and between group 3 and group 4(p>0.05). 3. The obliteration effect of dentinal tubules by a Nd:YAG laser irradiation was relatively stable to tetracycline HCI. The results demonstrate that a pulsed Nd:YAG laser irradiation within 1.0W, regardless of irradiation methods, can obliterate dentinal tubules effectively.

• 한국산학기술학회논문지
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• 제11권4호
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• pp.1534-1539
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• 2010

본 연구는 서울시에 소재한 S중학교 1학년 251명, S남자고등학교 1학년 220명을 대상으로 구강검진을 실시한 결과 아래와 같다. 구강증상에 대한 중, 고등학생들의 치아 지각과민 경험은 고등학생이 23.2%로 중학생 14.3%보다 차갑고 뜨거운 음료 혹은 음식을 마시거나 먹을 때 치아가 아픈 경험이 있었으며, 유의한 차이를 보였다($\chi^2=6.08$, p<.05). 치아 통증에 대한 경험은 고등학생이 9.1%로 중학생 4.4%보다 치아가 쑤시고 욱신거리고 아픈 경험이 있었으며, 유의한 차이를 보였다($\chi^2=4.23$, p<.05). 중학생과 고등학생의 구강건강행태 결과 중학생이 48.6%로 고등학생 26.4%보다 지난 1년 간 치과병원을 간 적이 더 높게 나타났으며, 통계적으로도 유의한 차이를 보였다($\chi^2=24.56$, p<.001). 하루 동안 잇솔질 시기는 중학생이 68.5%로 고등학생 57.3%보다 아침식사 후에 이를 많이 닦았으며($\chi^2=6.39$, p<.05), 점심식사 후에는 고등학생이 16.8%로 중학생 7.2%보다 이를 많이 닦았으며, 통계적으로도 유의한 차이를 보였다($\chi^2=10.58$, p<.01). 또한 중학생과 고등학생의 구강검사 판정결과 고등학생이 44.1%로 중학생 22.3%보다 우식치아가 많았으며($\chi^2=25.36$, p<.001), 중학생이 9.6%로 고등학생 4.1%보다 상실치아가 더 많았고, 통계적으로도 유의한 차이를 보였다($\chi^2=5.39$, p<.05).

• Restorative Dentistry and Endodontics
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• 제33권2호
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• pp.141-147
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• 2008

본 연구의 목적은 나노리터 수준의 물 흐름을 계측할 수 있는 장치를 개발하고, 상아질의 물 투과성을 측정하여 치아과민증 치료제와 상아질 접착제의 상아세관 밀폐효과를 알아보고자 하였다. 본 연구에서 제작한 미세흐름 측정장치는 첫째, 물의 흐름을 감지하는 모세관과 광 센서부, 둘째 물의 흐름을 추적하는 서보모터와 구동부, 셋째, 모터의 회전을 측정하여 물의 이동량으로 변환하는 엔코더와 컴퓨터 기록장치 등 세 부분으로 구성되어 있다. 본 장비를 이용하여 교합 면이 절단되어 노출된 상아질의 물 투과도와 치아과민증 치료제인 BisBlock과 자가부식형 상아질접착제인 Clearfil SE bond의 상아질 밀폐효과를 측정하여 다음과 같은 결과를 얻었다. 1. 나노리터 수준의 물 흐름을 측정할 수 있는 장치를 제작하였고, 이를 이용하여 상아질의 물 투과도를 측정할 수 있었다. 2. 삭제 후 노출 연마된 상아질은 0.84 - 15.2 nL/s의 물 투과도를 보였고 Oxalate 제재인 BisBlock 이나 자가부식형 접착제 Cleafil SE bond 적용 시 투과도가 39.8 - 89.6% 감소하였다.

• Journal of Periodontal and Implant Science
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• 제32권3호
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• pp.555-584
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• 2002

Exposed root surfaces can cause esthetic problems, hypersensitivity, and root caries. Numerous efforts have been tried to cover the recessed root surfaces, and various techniques have been developed and introduced. Among these, subepithelial connective tissue graft which shows high coverage rate in various researches, has the advantage of good color match, less discomfort to the donor site, rich vascularity, and high predictability. Following results were obtained after investigating 6 and 18 months post operatively, 98 cases of subepithelial connective tissue graft from 48 patients who underwent subepithelial connective tissue graft procedure in the department of periodontology, college of dentistry, Yonsei university. 1. The total average root coverage of Miller class I, II & III were 76.2?24% at 6 months follow-up and 75?25.2% at 18 months follow-up with no statistically significant difference between the follow-up periods.(p<0.05) 2. The percentage of teeth showing complete coverage were 41.9% at 6 months follow-up and 39.2% at 18 months follow-up. 3. At 6 months follow-up, Miller classification I showed 84.9?20.7%, class II showed 82.5?17.7%, and class III showed 62.3?24.5% of coverage. In class III recession, statistically significantly less root coverage was observed compared to class I & II. (p(0.05) 4. At 18 months follow-up, Miller classification I showed 92.2?13.5%, class II showed 84.3?17.4%, and class III showed 59.5?24.5% of coverage. In class III recession, statistically significantly less root coverage was observed compared to class I & II. (p<0.05) In conclusion, subepithelial connective tissue graft for class I and II recession can be used as a clinically predictable treatment modality for root coverage.

• Journal of Periodontal and Implant Science
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• 제28권1호
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• pp.37-56
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• 1998

The purpose of this study was to evaluate the clinical and microbiological outcomes following the use of 30% minocycline-loaded polycaprolacton film and 2% minocycline-loaded gel that was applied locally into pockets combined with scaling and root planing. 25 human subjects who were non-pregnant, non-lactating, aged 20-50 and diagnosed as moderate to advanced adult periodontitis were enrolled. Subjects were excluded if they had a history of severe acute or chronic systemic disease, if they required antibiotic prophylaxis for dental treatment for any reason, or if they reported a history suggestive of hypersensitivity reactions to minocycline or tetracycline. 4quadrants that had several teeth with a 5-8mm probing pocket depth and radiographic evidence of alveolar bone loss for each patient were selected and divided into test sites and control sites according to the split-mouth design. Scaling and root planing was done for each site at baseline(0week). Test sites received the minocycline gel and strip and control sites had saline irrigation. The patients received both treatments simyltaneously. Subgingival irrigation of sterile saline was applied to the control sites for approximately 30 seconds. Minocycline strip and gel was applied into the periodontal pocket at 1, 2, 3, 4 weeks each after scaling and root planing in the test sites. The clinical and microbiological measurements were made at baseline and at the follow-up visits 6, 10, 14, 20 weeks. The results of this study were as follows; 1. The sulcular bleeding index, probing pocket depth and Periocheck test was significantly reduced and the relative proportions of spirochetes and motile rods were significantly reduced and the proportion of cocci was correspondingly increased, in locally delivered minocycline strip group compared to saline irrigation group. 2. In locally delivered minocycline gel group, The effect was the same with minocycline strip group as compared with saline irrigation therapy. 3. There was no significant differences between minocycline strip group and minocycline gelgroup. In conclusion, minocycline HCl local drug delivery combined with scaling and root planing may provide added improvement of clinical and microbiological responses by inhibiting bacterial recolonization of treated sites. It is suggested that the local administration of minocycline-HCl in the periodontal pocket is effective when combined with subgingival mechanical debridement.

• 대한한방부인과학회지
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• 제31권1호
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• pp.1-19
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• 2018

Objectives: The purpose of this study was to investigate the changes of early puerperium symptoms and Blood Stasis Index in women during the first two weeks after childbirth. Methods: 38 women staying at Korean postpartum management facilities were studied. Questionnaires were filled out on the date of arrival and departure. Changes in overall physical conditions including neuropsychiatric, circulatory, digestive, musculoskeletal, and urogenital and breast symptoms as well as Blood Stasis Pattern were studied. Results: 1. Neuropsychiatric symptoms were shown in order of Depressed Feeling, Insomnia, Dizziness, Headache, and Easy to Anger and Nervous on arrival. All symptoms showed improvement after two weeks, without significance. 2. Circulatory symptoms were shown in order of Excessive Sweating, Edema, Fatigue, Hot Flash, Anemic Feeling, Alternating Chills and Fever, Cold Hypersensitivity, Chills, Oppression in the Chest, and Palpitation on arrival. Hot Flash, Excessive Sweating, and Edema showed significant improvement after two weeks. 3. Digestive symptoms were shown in order of Dyspepsia, Dry Mouth, Constipation, and Loss of Appetite. All symptoms showed improvement after two weeks, without significance. 4. Pain of Muscles & Joints showed improvement after two weeks, without significance. Pain of Teeth & Gingiva showed slight worsening after two weeks, without significance. 5. Urogenital and Breast symptoms were shown in order of Wound Pain, Fever and Distending Pain in the Breast, and Lower Abdominal Pain on arrival. All symptoms showed significant improvement after two weeks. 6. Blood Stasis Index showed significant improvement after two weeks. Conclusion: Most symptoms were improved in women staying at Korean postpartum management facilities for two weeks. Hot Flash, Excessive Sweating, Edema, Wound Pain, Lower Abdominal Pain, Fever and Distending Pain in the Breast and Blood Stasis Index showed significant improvement.