• Journal of Radiation Protection and Research
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• 제25권4호
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• pp.183-190
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• 2000

본 연구에서는 천연 약용작물 추출물을 대상으로 하여 산화적 스트레스 하에서 상피세포암 세포 생장억제의 상승효과를 검색하였다. 한국인 호발암인 간암, 위암 및 대장암 등에 효과가 있다고 보고된 총 51 종의 천연 약용작물을 선정하여 메탄올 추출물 시료를 제조하고 , 과산화수소에 의해 유도된 산화적 스트레스 하에서 이 추출물의 암세포생장억제상승효과를 검색하였다. 사용된 51종의 시료 중 27 시료가 다양한 정도의 활성을 나타내었다. 활성이 나타난 27 시료 중 고련피, 곽향, 노나무, 도인, 방기, 백두웅, 백화사설초, 전호, 오미자, 조각자, 천궁의 11시료에서 산화적 스트레스 부가시 $IC_{50}$ 값이 50% 이상 감소되었으며, 다른 16 시료엣 50-25%의 $IC_{50}$ 값의 감소가 나타났다. 우수한 상승효과를 나타낸 11 시료는 산화적 스트레스에 용량 의존적인 상승효과를 나타내었다. 그 중 가장 우수한 상승효과를 나타낸 시료는 노나무(Catalpa ovata)로서 과산화수소수 75 및 100 uM을 가하여 산화적 스트레스를 부가하였을 때 각각 61 및 28%의 $IC_{50}$ 값의 감소를 초래하였다. 그 외 고련피, 곽향, 도인, 백두옹, 오미자 등이 우수한 효과를 나타내었다.

• Imaging Science in Dentistry
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• 제33권3호
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• pp.143-149
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• 2003

Purpose: To investigate the radiosensitivity of the normal human oral keratinocytes (NHOK), and the effect of irradiation on cell cycle and protein expression. Materials and Methods: To evaluate the radiosensitivity of NHOK, the number of colonies and cells were counted after irradiation and the SF2 (survival fraction at 2Gy) value, and the cell survival curve fitted on a linear-quadratic model were obtained. LDH analysis was carried out to evaluate the necrosis of NHOK at 1, 2, 3, and 4 days after 2, 10, and 20 Gy irradiation. Cell cycle arrest and the induction of apoptosis were analyzed using flow cytometry at 1, 2, 3, and 4 days after 2, 10, and 200y irradiation. Finally, proteins related cell cycle arrest and apoptosis were analysed by Western blot. Results: The number of survived cell was significantly decreased in a dose-dependent manner. The cell survival curve showed SF2, α, and β values to be 0.568, 0.209, and 0.020 respectively. At 200y irradiated cells showed higher optical density than the control group. After irradiation, apoptosis was not observed but G2 arrest was observed in the NHOK cells. 1 day after 10 Gy irradiation, the expression of p53 remained unchanged, the p2l/sup WAF1/Cipl/ increased and the mdm2 decreased. The expression of bax, bcl-2, cyclin B1, and cyclin D remained unchanged. Conclusion: These results indicate that NHOK responds to irradiation by G2 arrest, which is possibly mediated by the expression of p21/sup WAFl/Cipl/, and that cell necrosis occurs by high dose irradiation.

• Journal of Korean Dental Science
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• 제5권1호
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• pp.7-12
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• 2012

Purpose: To examine the antibacterial effectiveness of silver nanoparticles (SNP) mixed with commercial orthodontic adhesives. Materials and Methods: SNP was prepared by dissolving silver perchlorate in an organic solvent and reducing it with ultraviolet radiation. SNP was then mixed with four commercial orthodontic adhesives (Light Bond, Blugloo, Transbond XT, and Fuji Ortho LC) (0.05 wt %), which were then formed into disc-shape specimens ($8.0mm{\times}3.0mm$). Commercial orthodontic adhesives containing no SNP were used as the control groups. Specimens of the four experimental and four control groups were incubated with streptococcus mutans and the medium turbidity was assessed at 3, 6, 9, 12, and 24 hours after incubation. The agar diffusion test was also performed to examine the growth inhibition zone of these groups. The data were statistically analyzed using a Wilcoxon rank sum test and t-test with a Bonferroni's correction (P<0.05). Result: The SNP containing groups had a superior antibacterial effect compared to the control groups. In the agar diffusion test, the control groups without SNP did not produce an inhibition zone, whereas the SNP containing groups showed inhibition zone of 10~13 mm. Conclusion: The incorporation of SNP into orthodontic adhesives can inhibit cariogenic bacterial growth.

• 한국방사선학회논문지
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• 제13권3호
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• pp.459-464
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• 2019

치과 콘빔 전산화단층 검사 시 갑상선 부위의 방사선 피폭선량을 최소화하기 위하여 보루스 (Bolus)를 이용한 차폐체를 제작하고, 방사선 차폐 효과와 영상의 적정성을 평가하였다. 치과용 콘빔 전산화단층검사장비를 사용하여 치과방사선 두부 팬텀을 대상으로 갑상선의 좌, 우측 부위에 유리선량계를 부착시켜 방사선량을 측정하였다. 차폐체의 두께를 각각 10 mm, 20 mm, 30 mm로 다르게 하여 각 차폐체별로 흡수선량을 측정하여 차폐체를 사용하지 않았을 경우와 비교하였다. 8명의 평가자가 진료영상의 적정성을 여부를 평가하였다. 왼쪽 갑상선 부위에 30 mm Bolus 차폐체를 사용한 경우에는 결과값이 평균 $342.67{\mu}Gy$로 Bolus 차폐체를 사용하지 않고 측정한 결과값의 평균 $431.22{\mu}Gy$보다 20.7% 감소하였고, 오른쪽 갑상선 부위에 30 mm Bolus 차폐체를 사용한 경우에는 평균 $424.56{\mu}Gy$로 21.9%의 선량감소효과를 보였다. 진료 영상의 적정성은 평가자 모두 사용 가능하다 판단하였다. 결론적으로, 치과 콘빔 전산화단층검사 시 갑상선 부위의 방사선 피폭선량을 최소화하기 위해 제작된 Bolus 차폐체는 장해음영 없이 적정한 진단 영상 처리가 가능하고, 방사선차폐 효과가 있어 유용한 차폐체로 적용 가능할 것으로 사료된다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제12권3호
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• pp.23-33
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• 1990

A clinical study of selected patients with intraoral squamous cell carcinoma which were managed in the Department of Oral Oncology of Korea Cancer Center Hospital from January 1982 to August 1989 was done. And following results were obtained. 1. Males were involved more than females by intraoral squamous cell carcinoma in a ratio of 4:1. and most of the cases occurred in the 7th and 6th decades (69%). 79% of total patients and 92.5% of males were. 2. The mean duration of symptomatic period was 5.9 months. 3. The common symptoms were swelling (63%), pain (40%), ulceration (33%), and trismus (23%) 4. In the histologic findings, well differentiation comprised 58.0%. 5. The primary sites were the upper alveolar mucosa (32%), the floor of the mouth (21%), the lower alveolar mucosa (19%), tongue (14%), retromolar trigone (8%), palate (7%) and buccal mucosa (3%). 6. According to TNM system, Stage I, Stage II, Stage III, and Stage IV comprised 4%, 15%, 32%, and 49% respectively. 7. In the management of intraoral squamous cell carcinoma, surgeries were done in the 32 cases, 23 cases of which were managed by radiation therapy or chemotherapy concurrently. And radiation therapy alone was received in 35 cases. 8. Overall 3 and 5-year survival rates without regarding to stage were 27.6% and 21.4%. 9. 3-year survival rate of female patients was 47.2% and that of male patients was 22.6%. 10. 5-year survival rate was 53.9% for "early" cancer (stage I and II) and 15.6% for "advanced"cancer (stage III and IV). Survival rate of patients in the early stages of cancer appeared to be higher than that of patients with stage III and IV(p<0.05).

• Restorative Dentistry and Endodontics
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• 제9권1호
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• pp.15-24
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• 1983

Irradiation is frequently employed as the sole therapy for oral cancer. These irradiated patients presents peculiar and progressive dental problems. But there is only scanty informations concerning specific approaches to endodontic treatment for head and neck cancer patients who have been subjected to tumorcidal doses of radiation therapy. The purpose of the present study was to determine the effects of cobalt-60 radiation on the pulpal healing of dogs after the direct pulp capping. As the experimental animals, 10 dogs (above 7-8 months after birth) were divided into 3 groups (Control, Group I, Group II). The cobalt-60 was irradiated to the Group I and Group II each 1,009 and 1,562.5 rads as single dose. As the capping material Dycal$^{(R)}$(L.D. Caulk company) was selected. After the direct pulp capping the dogs were sacrified 1, 2, 3, 4, week interval and made the original slides cut with a thickness of 8 microns and stained with hematoxylin and eosin. After examination and comparision of all specimen, the results of this study were drawn as follows; 1. The formation of reparative dentin was observed from the 1st week in the Control group, the 2nd week in the Group I & II. The few and irregular tuble structure was appeared in the 4th week in the Control group only, but failed in the Group I & II. 2. The continuity of dentin bridge was appeared in the 3rd week in all group and the degeneration of odontoblast in the 1st week of the Group II. 3. The congestion and hemorrhage in the pulp tissue were observed in all groups until 3rd week. The inflammation was appeared within the 2nd week in the Group I and especially marked in the Group II, but absent in the Control group. 4. In cases Dycal into the pulp tissue deeply, the local necrosis of pulp and decrease of dentin formation was observed.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제27권4호
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• pp.388-393
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• 2005

Chondroblastoma was introduced as a rare benign cartilaginous neoplasm by Codman in 1931. It described by Jaffe and Lichtenstein in 1942 as a benign cartilaginous neoplasm that represents less than 1% of all primary bone tumor. It commonly arises in the epiphysis of long bone but, it occurs very rare in temporal area. Sometimes, microscopic identification of chondroblastoma and giant cell granuloma is difficult. An immunohistochemical studies was performed for S-100 protein which is useful in arriving at the correct diagnosis. Treatment modalities are total curettage, en-bloc excision, irradiation, and radiation combined with surgical excision. But radiation therapy was controversial. We describe a case of chondroblastoma which was arisen in the right temporal area and the recurrence that was treated by surgical excision and radiation therapy with review of literature.

• Journal of Oral Medicine and Pain
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• 제35권1호
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• pp.31-39
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• 2010

치주염이나 구취발생과 관련된 구강미생물에 대한 저출력레이저의 살균효과를 관찰하기 위하여, Porphyromonas gingivalis 2561 (P. gingivalis 2561), Prevotella intermedia (Pr. intermedia)에 광감수성증가물질을 처리함으로써 실험균주의 광민감성을 증가시킨 후 저출력레이저 650nm의 파장을 연속적으로 1분, 2분, 3분, 5분간, 각각 1cm, 2cm, 3cm 거리에서 조사하여 다음과 같은 결과를 얻었다. 1. P. gingivalis 2561의 경우 Toluidine blue O(TBO) 처리 후 650nm의 파장으로 3cm의 거리에서 1분간 조사한 실험군은 TBO만 처리한 실험대조군에 비해 99.99% 이상의 항균효과를 나타내었다. 2. Pr. intermedia의 경우 TBO 처리 후 650 nm의 파장으로 3 cm의 거리에서 1분간 조사한 실험군은 TBO만 처리한 실험대조군에 비해 99.8% 이상의 항균효과를 나타내었다. 3. P. gingivalis 2561의 경우 TBO 처리 후 650 nm의 파장을 연속으로 각각 1분, 2분, 3분간 조사한 실험군의 경우 시간이 길어질수록 살균효과가 점차 증가되었다. 4. P. gingivalis 2561의 경우 조사거리가 1 cm, 2 cm, 3 cm으로 증가할수록 살균효과가 약간 감소되었다. 5. Pr. intermedia의 경우 조사거리가 1 cm, 2 cm, 3 cm으로 증가할수록 살균효과가 약간 감소되었다. 위와 같은 결과를 바탕으로 저출력레이저의 살균효과는 조사시간이 길어질수록, 조사거리가 짧을수록 살균효과가 증가되었는데, 살균효과가 가장 적게 나타난 3 cm의 거리에서 1분간 조사한 실험군에서도 TBO만 처리한 경우보다 99.8% 이상의 살균효과를 나타내었으므로 저출력레이저의 구강미생물에 대한 살균효과는 명백하다고 생각된다. 따라서 photosensitizer의 부작용이 없는 한계 내에서 사용한다면 저출력레이저가 치주염, 임플란트주위염 등에 대한 보조적 치료와 구취조절 등에 매우 유용하게 사용되리라고 생각된다.

• Restorative Dentistry and Endodontics
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• 제36권5호
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• pp.367-376
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• 2011

치아우식증의 조기 발견은 외과적 삭제를 피하면서, 적절한 치료를 할 수 있는 좋은 기회를 제공한다. 광간섭단층촬영술은 최근 각광받기 시작한 3차원 이미지 기술로서, 안과에서 광학적 생검의 목적으로 빈번히 이용되는 것을 필두로 다양한 의학 분야에 적용되어 왔고, 최근 초기 우식증의 발견에 전도유망하여 다양한 연구가 진행 중이다. 이 기술은 저 상관도 간섭계의 원리에 근거하고 있으며, 장점으로는 비침습적이고, 방사선을 사용하지 않으며, 3차원 이미지 구축이 가능하다는 점이다. 본 연구에서는 광간섭단층촬영술의 원리와 개략적인 개발 과정에 대한 기술과 함께 치아우식증에 관한 연구들에 대하여 고찰해 보았고, 이를 통해 이 기술의 응용 가능성을 확인하였다. 그럼에도 불구하고, 임상적인 유용성을 입증하기 위해서는 몇 가지 기술적 문제를 해결해야 하고, 보다 많은 생체 내 실험이 뒷받침되어야 할 것이다.

• 치과방사선
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• 제28권1호
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• pp.127-143
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• 1998

The author evaluated the effects of taxol, a microtubular inhibitor, as a possible radiation sensitizer and the production of prostaglandins on three human cancer cell lines(KB, RPMI-2650 and SW-13) and one murine cell line(L929). Each cell line was divided into four groups (control, taxol only, radiation only and combination of taxol and radiation). The treatment consisted of a single irradiation of 10Gy and graded doses (5, 50, 100, 200, 300, 500 nM) of taxol for a 24-h period. The cytotoxicity of taxol alone was measured at 1 day after(1-day group) and 4 days after(4-day group) the treatment. The survival ratio of cell was analyzed by MTT (3-(4,5-dimethylthiazol-2-yl) -2,5-dimethyl tetrazolium bromide) test. Prostaglandins(PGE2 and PGI2) were measured in the culture medium by a radioimmunoassay. The results obtained were as follows. 1. There was a significantly increased cytotoxicity of KB cells in 4-day group than those in I-day group. There was a high correlation between doses of taxol and cell viability in both groups(l-day group R=0.82741, 4-day group R=0.84655). 2. There was a significantly increased cytotoxicity of RPMI -2650 cells treated with high concentration of taxol in 4-day group than those in I-day group. Also there was a high correlation between doses of taxol and cell viability in 4-day group(R=0.93917). 3. There was a significantly increased cytotoxicity of SW-13 cells treated with high concentration of taxol in 4-day group than those in 1-day group. However no high correlation was observed between doses of taxol and cell viability in both groups(1-day group R=0.46362, 4-day group R=0.65425). 4. There was a significantly increased cytotoxicity of L929 cells treated with low concentration of taxol in 4-day group than those in 1-day group. At the same time, there was a low correlation between doses of taxol and cell viability in both groups(1-day group R=0.34237, 4-day group R=0.23381). 5. In I-day group of L929 cells, higher cytotoxicities were observed in the groups treated with 500 nM taxol than given 10 Gy radiation alone. L929 cells in I-day group alone showed a radiosensitizing effect by taxol.. 6. In addition to L929 cells, all cancer cells treated with a combination of taxol and radiation in 4-day group appeared to have some fragmented nuclei and to float on the medium. In addition, L929 cells appeared to be more confluent. 7. The level of PGE2 production was the highest in the contol KB cells. This appeared to increase in every experimental group of all three cancer cells except L929 cells. There was a significantly increased production of PGE2 in SW -13 cells treated with a combination taxol and radiation compared to the other experimental groups. 8. The level of PGE2 production in the control group of RPMI-Z650 cells was the highest. This appeared to increase in every experimental group of all cells except in SW-13 cells. This also increased significantly in RPMI-2650 cells treated with a combination of taxol and radiation compared to the other experimental groups.