• 대한치주과학회:학술대회논문집
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• 대한치주과학회 2004년도 제44회 종합학술대회 연제초록
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• pp.58-59
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• 2004

• Journal of Periodontal and Implant Science
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• 제29권4호
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• pp.893-914
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• 1999

Tooth mobility may be the decisive factor that determines whether dental treatment of any kind is undertaken. Although tooth mobility in isolation says little in itself, the finding of increased tooth mobility is of both diagnostic and prognostic importance. Only the detection of an increase or decrease in mobility makes an evaluation possible. Thus prior to treatment, we must understand the pathologic process causing the observed the tooth mobility and decide whether the pattern and degree of observed tooth mobility is reversible or irreversible. And then it must be decided whether retention and treatment or extraction and replacement. The purpose of this study was to compare tooth mobility at different time period during root planing and flap operation and to relate changes in mobility to each treatment method. Twenty-one patients (287 teeth) with chronic adult periodontitis were treated with root planing(control group) and flap operation(experimental group), and each group was divided 3 subgroups based upon initial probing pocket depth (1-3mm, 4-6mm, 7mm and more). Tooth mobility was measured with $Periotest^{(R)}$ at the day of operation, 4 days, 1 week, 2 weeks, 3 weeks, 4 weeks, 8 weeks, 12 weeks after each treatment. Tooth mobility, attachment loss, radiographic bone loss, and bleeding on probing were measured at the day of operation, 4 weeks, 8 weeks and 12 weeks after treatment. 1. In group initial probing depth was 1-3mm, tooth mobility had no significant difference after root planing and flap operation. 2 . In group initial probing depth was 4-6mm, 7mm and more, tooth mobility had decreased in 12 weeks after root planing(p<0.01). And the mobility had increased after flap operation(p<0.01) and was at peak in 1 week, and decreased at initial level in 4 weeks, below the initial level in 12 weeks(p<0.01). 3. In 1 week, significant difference in tooth mobility between control and experimental group was found(p<0.01) but, in 12 weeks no difference between two groups was found. 4. Change of immediate tooth mobility after treatment was more larger in deep pocket than in shallow one. In group with the same probing pocket depth, the change of tooth mobility in molar group was greater than that of premolar group. 5. Tooth mobility before treatment was more strongly correlated with radiographic bone loss (r=0.5325) than probing depth, attachment loss and bleeding on probing, in 12 weeks after treatment, was more strongly correlated with attachment loss($r^2$=0.4761) than probing depth and bleeding on probing. Evaluation of the treatment effect and the prognosis after root planing and flap operation were meaningful on tooth initial probing depth 4mm and more. After flap operation, evaluation of the prognosis should be performed at least in 4 weeks and in 12 weeks after treatment, no difference in tooth mobility between two groups was observed. Radiographic bone loss and attachment loss were good clinical indicators to evaluate tooth mobility.

• 대한치과의사협회지
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• 제53권11호
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• pp.795-803
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• 2015

A questionnaire-based survey was done to evaluate the patients' perception on the use of Rubber Dam (RD) for the tooth isolation during dental treatment. Total 106 questionnaire were gathered and the data were analyzed according to the patients' gender, age, previous experience of RD. The 96% of total patients reported no experience of RD in their previous treatment. The first advantage of RD was selected as the protection of irrigant and medication into the oral cavity and the disadvantage was selected as saliva gathering during treatment. 98% of patients want to use RD for the next treatment and 99% remarked that the RD is essential for the dental treatment. Based on the surveyed data, majority of the patients highly satisfied with the RD use and they want to use RD and may consider the use of RD for the selection of dental clinic.

• Restorative Dentistry and Endodontics
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• 제43권2호
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• pp.17.1-17.7
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• 2018

Iatrogenic perforations negatively impact the outcome of endodontic treatments. Studies on prognostic factors showed that perforations in the coronal third of the root with periodontal pocket formation have an unfavorable prognosis. A 36-year-old female was referred for endodontic evaluation of tooth #13 with a history of an iatrogenic perforation, happened 3 years ago. There was a sinus tract associated with perforation, 10 mm probing on the mesial and mesio-palatal, bleeding on probing, radiolucent lesion adjacent to the perforation and complete resorption of the interdental bone between teeth #13 and #12. After the treatment options were discussed, she chose to save the tooth. The tooth was accessed under rubber dam isolation, the perforation site was cleaned and disinfected using 0.5% sodium hypochlorite and sealed with calcium-enriched mixture cement. Eighteen months after treatment the tooth was functional and asymptomatic. The probing depths were normal without bleeding on probing. Radiographically, the interdental crestal bone formed between teeth #13 and #12. Despite all negative prognostic factors in this case (i.e., perforations in the coronal third, pocket formation, and radiolucent lesion), healing was unexpectedly achieved via non-surgical repair of the perforation. Further research on biological aspects of healing in the periodontium following iatrogenic perforations are recommended.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제35권6호
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• pp.353-359
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• 2013

Purpose: Extensive research is actively ongoing for development of an ideal bone substitute that meets the gold standard. Tooth was selected as a donor site for evaluation of potentials in bone substitutes based on its similar chemical compositions to alveolar bone. Previous studies have evaluated inorganic components of autogenous tooth bone graft material (AutoBT) and osteoconductivity. In continuation from the previous studies, the current study was conducted for analysis of organic components and evaluation of osteoinductivity of AutoBT. Methods: Forty-six extracted teeth were collected from actual patients (Korea Tooth Bank, R&D Institute). Extracted teeth were processed into AutoBT and implanted in dorsal subcutaneous muscular tissues of 15 athymic mice. Biopsy samples were harvested at two, five, and eight weeks. The Bradford assay, sodium dodecyl sulphate polyacrylamide gradient gel, and western blotting were performed for investigation of organic contents of AutoBT. Results: Histology analyses showed signs of new bone formation as early as two weeks. Results of the Bradford assay indicated the existence of noncollagenous proteins (NCP). 0.29% (2.89 mg/g) of proteins were extracted by weight in the root portion of AutoBT; 0.02% (0.029 mg/g) and 1.79% (17.93 mg/g) of proteins were measured by weight in crown and block-form of AutoBT, respectively. However, recombinant human bone morphogenetic protein-2 was not observed in AutoBT. Conclusion: Within the limitation of the current study, AutoBT induced new bone formation by NCP embedded in dentin.

• 구강회복응용과학지
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• 제25권2호
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• pp.191-200
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• 2009

줄기세포는 미분화 상태의 세포로 지속적인 자가 분열능과 특정 세포로 분화 할 수 있는 분화능을 지니고 있으며 이러한 특성으로 말미암아 난치병의 새로운 장을 열 것이라는 기대감을 얻고 있다. 즉, 세포이식 후 특정 세포로 분화 유도를 시켜 기존의 치료 방법으로는 치료가 되지 않았던 많은 의학적 난제들을 풀 수 있는 열쇠인 것이다. 치아는 평생에 걸쳐 발거되는 조직으로 치아줄기세포는 얻기가 비교적 쉬워서 다른 성체줄기세포들보다 더 높이 평가되고 있다. 과잉치는 전 세계 다양한 인종에서 발견되는 중요한 임상적 질환이다. 과잉치의 유병율은 관련 연구 보고서마다 다양하나 소아치과 의사들의 경우 임상에서 자주 과잉치를 발거하고 있다. 그러나, 현재까지 진행된 줄기세포 관련 연구들을 살펴보면 과잉치의 줄기세포에 관한 보고는 없으며, 이는 줄기세포로 이용 가능한 중요한 자원을 파기하고 있는 것은 아닌지 의문이 생긴다. 그러므로 본 연구는 과잉치에 포함된 세포가 줄기세포의 특징을 가지고 있는지를 밝혀내기 위해 진행되었다.

• Restorative Dentistry and Endodontics
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• 제38권4호
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• pp.258-262
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• 2013

The restorative management of deep carious lesions and the preservation of pulp vitality of immature teeth present real challenges for dental practitioners. New tricalcium silicate cements are of interest in the treatment of such cases. This case describes the immediate management and the follow-up of an extensive carious lesion on an immature second right mandibular premolar. Following anesthesia and rubber dam isolation, the carious lesion was removed and a partial pulpotomy was performed. After obtaining hemostasis, the exposed pulp was covered with a tricalcium silicate cement (Biodentine, Septodont) and a glass ionomer cement (Fuji IX extra, GC Corp.) restoration was placed over the tricalcium silicate cement. A review appointment was arranged after seven days, where the tooth was asymptomatic with the patient reporting no pain during the intervening period. At both 3 and 6 mon follow up, it was noted that the tooth was vital, with normal responses to thermal tests. Radiographic examination of the tooth indicated dentin-bridge formation in the pulp chamber and the continuous root formation. This case report demonstrates a fast tissue response both at the pulpal and root dentin level. The use of tricalcium silicate cement should be considered as a conservative intervention in the treatment of symptomatic immature teeth.

• 대한소아치과학회지
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• 제25권2호
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• pp.277-284
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• 1998

For the purpose of comparing the shear bond strengths of pit and fissure sealants, and finding out the more efficient method of tooth surface treatment when the etched surface is contaminaed by saliva or moisture, an experiment was performed on 3 types of pit and fissure sealants. 120 extracted human molars were divided into 3 groups, each of which was composed of 40 specimens sealed with Helioseal, Teethmate-F and Fuji III respectively. And each groups was again divided into 4 subgroups according to tooth surface treatment. The shear bond strengths of each groups and subgroup was measured and statistically analyzed. The results obtained were as follows : 1. Shear bond strengths of nonfluoridated resin sealant, Helioseal were shown to be higher than those of fluoridated resin sealant, Teethmate-F, but, not significantly different. 2. Shear bond strengths of GI sealant, Fuji III were to be markedly lower than those of two resin sealants. 3. When there is moisture contamination, applying primer under sealant(Group IV) results in a significantly stronger bond strength of sealant to enamel than when using sealant alone(Group II) in case of all sealants. 4. When there is no moisture contamination, using primer under sealant (Group III) results in bond strength equivalent to bond strength on using sealant alone (Group I). 5. Based on the results above, it was demonstrated that the bond of sealant to tooth surface is greatly affected by saliva contamination and that the complete tooth isolation method should be fully emphasized. The application of primer is recommended when performing sealant under the environment very susceptible to saliva contamination.

• 한국전자파학회논문지
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• 제11권4호
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• pp.505-513
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• 2000

본 논문에서는 편파 다이버서티(j:X)larization diversity)용 광대역 안테나에 대한 성능을 개선하기 위한 새로운 구조를 제안하였다. 이중 편파 마이크로스트립 안테나를 구현하기 위하여 십자형 개구변을 두었고, 개구면 위와 아래에 두 j:X)rt가 서로 수직이 되도록 급전부를 셜계하였다. 그리고 방사소자와 급전부에 air gap을 주었으며 후 방 방사를 줄이기 위해 아래 급전부로부터 $\lambda$/4 떨어뜨려서 반사판을 두었다. 더욱 넓은 대역폭을 가지도록 방 사 패치에 톱니 모양의 perturbation을 주었으며, 패치의 perturbation 효과에 의해 안테나 크기가 줄어들게 됨으 로써 배열 안테나의 크기도 상당히 줄어들었다. 제안된 단일 소자 안테나를 이용하여 $1\times4$ 배열 안테나 구조를 가진 PCS 기지국용 편파 다이버시티 안테나 를 제작하였다. 단일 소자 안테나는 각각 port 당 10.3 %, 11.3 %(VSWR<1.3)의 대역폭을 가지고 두 port간의 분리도가 -40 dB 이상이다. 또한 배열 안테나의 대역폭은 각각 13.2 %, 12.7 %(VSWR <1.3)이고 -36 dB의 분 리도와 10 dB의 XPD를 가진다.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
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• pp.546.2-546
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• 2003

Dental follicle is the mesenchymal tissue which surrounds developing tooth germ. During tooth root development, periodontal components such as cementum, periodontal ligament and alveolar bone are considered to be created by progenitors present in the dental follicle. However, little is known about these progenitors. Previously we observed that cultured bovine dental follicle cells (BDFC) contained putative cementoblast progenitors. To further analyze the biology of these cells, we have attempted to immortalize BDFC by expression of the polycomb group protein Bmi-1 and human telomerase reverse transcriptase (hTERT). The BDFC expressing Bmi-1 and hTERT showed extended life span by 90 population doublings more than normal BDFC, and still contained cells with potential to differentiate into cementoblasts upon implantation into immunodeficiency mice. Among them, we established a clonal cell line designated as BCPb8, which formed cemetum-like mineralized tissue reactive to anti-cementum specific monoclonal antibody, 3G9, and expressed mRNA for bone sialoprotein, osteocalcin, osteopontin and type I collagen upon implantation. Thus with the combination of hTERT and Bmi-1, we succeeded in immortalization of cementoblast progenitor in BDFC without affecting differentiation potential. The BCPb8 progenitor cell line could be a useful tool not only to study cementogenesis but also to develop regeneration therapy for periodontitis.