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EFFECTS ON ER,CR:YSGG LASER ON PERI-IMPLANTITIS (임프란트 주위염에 대한 Er,Cr:YSGG 레이저 조사가 미치는 영향)

  • Choi, Sung-Lim;Kim, Jin-Hwan;Hwang, Dong-Hyeon;Min, Seung-Ki
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.30 no.5
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    • pp.428-436
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    • 2008
  • For Longevity of implant, considerations of biomechanical and microbiological aspects must be done. Recently, due to the remarkable development of bone grafting procedure. Implant has been implanted into the more favorable sites but peri-implantitis resulted from periodontal bacteria may obscure the long-term prognosis. Although many different modalities have been introduced to treat the failed implant. Implant's surface and irreversible bony destruction around the implant prevents good result. After Er,Cr:YSGG (waterlase) laser using the wave-length of 2780nm has been introduced to dental field, good results have been reported. Because waterlase uses the hydrokinetic force of water. It is excellent device to detoxify the implant surface mechanically without the heat generation and damage to the implant surface. We designed to evaluate waterlase effect on the peri-implantitis has been occurred after implantation. Four beagle dogs were involved. We have made four premolar extraction in each right and left side of the lower jaw and placed two implants in the anterior of the jaw as a control and six implant were placed posterior in each socket after extraction immediately as an experimental group. We tied floss-silk in each implant to make peri-implantitis intentionally. After three months, we explored peri-implant sites on each experimental fixtures. Using waterlase laser irradiation was performed on that implantitis sites under 3W, air 30% and water 20% intensity for 2 minutes. In control group, we repositioned the flap to cover the exposed fixture without any supportive care. Three months later, we sacrificed experimental animals and extracted and preparated bone blocks with Donath and Breuner (982), Donath (988)'s methods and examined under microscope. We have obtained good re-osseointegration around fixtures after treating with waterlaser irradiation. But it was shown fibroosseointegration in the control group.

A radiographic evaluation of graft height changes after maxillary sinus augmentation

  • Kim, Do-Hyung;Ko, Min-Jeong;Lee, Jae-Hong;Jeong, Seoung-Nyum
    • Journal of Periodontal and Implant Science
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    • v.48 no.3
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    • pp.174-181
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    • 2018
  • Purpose: The aims of the present study were to quantitatively assess graft height changes after sinus lift procedures and to analyze the factors that influenced graft height changes, including the residual bone height before surgery, surgical approach, and tooth type. Methods: A total of 39 maxillary posterior implants placed during a simultaneous sinus lift procedure were evaluated. Panoramic radiographs of all patients were taken immediately after implant installation and at 3 months, 6 months, 1 year, 2 years, and 3 years. To analyze graft height changes over time, we measured the distance between the implant platform and the base of the grafted sinus floor at 3 locations. The radiographs were analyzed by a single examiner. Results: Graft height tended to decrease over time, and a statistically significant difference was observed at 2 years compared to baseline (P<0.05). There was no statistically significant difference in graft height change according to the surgical approach or tooth type. For residual bone height, a statistically significant difference in graft height change was found between those with 4-7 mm of residual bone height and those with ${\geq}7mm$ (P<0.05). Conclusions: Graft height after sinus lift procedures significantly decreased at 2 years compared to baseline after sinus augmentation. Further studies should be done with controlled variables, and prospective studies with 3-dimensional images are needed to clarify the factors that influence graft height changes.

Reconstruction of Soft Tissue Defect Caused by Excision of Soft Tissue Tumor Using Dorsalis Pedis Pedicled Island Flap (하지 연부조직 종양의 절제 후 발생한 결손의 재건을 위한 도서형 유경 피판술로서의 족배동맥 피판술)

  • Han, Chung-Soo;Shin, Dong-Jun;Moon, Jee-Soo;Park, Hyun-Chul
    • Archives of Reconstructive Microsurgery
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    • v.12 no.1
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    • pp.38-43
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    • 2003
  • Purpose : Various free flaps and pedicled island flaps are effective for reconstruction of soft tissue defect developed after tumor excision. We want to know the advantage of dorsalis pedis island flap for reconstruction of soft tissue defect caused by soft tissue tumor excision. Materials and Methods : Between 1992 and 2002, we performed 4 dorsalis pedis island flap procedure for reconstruction of soft tissue defect of lower limb developed after soft tissue tumor excision. Average age was 54.7 years old $(40{\sim}68)$, and male 2 cases, female 2 cases. The kinds and number of soft tissue tumors were 2 squamous cell carcinoma and 2 malignant melanoma. The procedures that we performed were all dorsalis pedis island flap. The analysis for the result of treatment was retrospectively accessed by physical examination and questionnaire for whether the change of symptom after operation, range of adjacent joint motion. Also we reviewed associated complication after operative treatment. Results : All dorsalis pedis island flaps were alive. There is no problem for activity of daily living, no skin necrosis and no limitation of motion of adjacent joint. In 1 case of them, the patients died of distant metastasis. Conclusion: Dorsalis pedis island flap procedure as a pedicled island flap procedure is very effective and easy operative procedure for reconstruction of soft tissue defect of lower limb developed after tumor excision compared to free flap procedure because there is no need for microvascular surgery, we can obtain relatively large flap and the lesion and flap donor site locate in the same limb.

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Development of Defects Detecting System for Corrugated Board, Mill Application, and Changes of Production Defects Ratio (골판지 불량 검색 시스템 개발, 현장적용과 생산 불량률 변화)

  • Jeong, Jin-Mo;Min, Kyung-Eun;Kim, Mun-Sung;Park, Jong-Moon
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.40 no.2
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    • pp.37-42
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    • 2008
  • Defects of corrugated board were limiting factors to the corrugated industry's growth. On-line detecting systems of defects are beneficial to increase profits of the corrugated board companies by reducing base paper consumption, increasing process reliability, and increasing productivity. By replacing naked eye inspection of defects to a defects detecting system, continuous inspection without fatigue may guarantee final products quality. The system was developed, which was consisted of line scan CCD camera, lens, illuminating parts, high speed image processor, software, various input parts, and output parts. First installation location of the system was at before fluting process after base paper unwinding, and surface of liner board was inspected by the system. Second installation location was after fluting process and combining process for liner board. Production loss includes ragged appearance of edge, irregular flute shape, wrong combination of flute, score cracking, defects in base paper, and flute cracking. The production loss was analyzed before and after the system installation at a commercial domestic mill. The production loss ratio was defined as a production loss weight per total production weight. The production loss ratio before the installation was decreased a lot from 1.28%(during 3 months before installation) to 0.76%(during 12 months after the first installation) and to 0.25%(during 6 months after the second installation).

Clinical and microbiological effects of the supplementary use of an erythritol powder air-polishing device in non-surgical periodontal therapy: a randomized clinical trial

  • Park, Eon-Jeong;Kwon, Eun-Young;Kim, Hyun-Joo;Lee, Ju-Youn;Choi, Jeomil;Joo, Ji-Young
    • Journal of Periodontal and Implant Science
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    • v.48 no.5
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    • pp.295-304
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    • 2018
  • Purpose: This study was undertaken to evaluate the clinical and microbiological effects of an erythritol powder air-polishing device (EPAP) as a supplement to scaling and root planing (SRP) therapy in patients with moderate chronic periodontitis. Methods: Clinical and microbiological evaluations were performed at 21 sites treated with SRP (control) and 21 sites treated with SRP+EPAP (test). All examinations were performed before treatment, 1 month after treatment, and 3 months after treatment. Results: There were no significant clinical differences between the test group and the control group. Microbiological analysis revealed that the relative expression level of Porphyromonas gingivalis was significantly lower in the test group than in the control group at 1 month after treatment. Clinical and microbiological results showed improvements at 1 month compared to baseline; in contrast, the results at 3 months after treatment were worse than those at 1 month after treatment. Conclusions: In this study, both SRP and SRP+EPAP were clinically and microbiologically effective as non-surgical periodontal treatments. In particular, the SRP+EPAP group showed an antimicrobial effect on P. gingivalis, a keystone bacterium associated with the onset of chronic periodontitis, in a short-term period. Periodic periodontal therapy, at intervals of at least every 3 months, is important for sustaining the microbiological effects of this treatment.

Screening for MiRNAs Related to Laryngeal Squamous Carcinoma Stem Cell Radiation

  • Huang, Chang-Xin;Zhu, Ying;Duan, Guang-Liang;Yao, Ji-Fen;Li, Zhao-Yang;Li, Da;Wang, Qing-Qing
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.8
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    • pp.4533-4537
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    • 2013
  • Objective: To use microarray chip technology for screening of stem cell radiation related miRNAs in laryngeal squamous cell carcinoma; study and explore the relationship of miRNAs with radiosensitivity of laryngeal squamous cells. Method: After conventional culture and amplification of the laryngeal squamous carcinoma cell line Hep-2, CD 133+ cells were screened out with combination of isolated culture of stem cell microspheres and FACS for preparation of laryngeal cancer stem cells. After radiation treatment, miRNAs of laryngeal squamous carcinoma stem cells before and after radiation were enriched and purified. After microarray hybridization with mammalian miRNA and scanning of fluorescence signal, the miRNAs of laryngeal squamous carcinoma stem cells before and after radiation was subject to differential screening and clustering analysis. Real-time quantitative RT-PCR was used to verify part of the differentially expressed miRNAs. Results: 70 miRNAs related to laryngeal cancer stem cell radiation with 2-fold difference in expression were screened out, in which 62 were down-regulated and 8 were up-regulated. Fluorescent quantitative RT-PCR results were consistent with miRNAs chip results. Conclusion: Some miRNAs may be involved in self-regulation with laryngeal squamous carcinoma stem cell radiation.

RUMINAL ACID CONCENTRATIONS OF GOATS FED HAYS AND SILAGES PREPARED FROM ITALIAN RYEGRASS AND ITS PRESSED CAKE

  • Ohshima, M.;Miyase, K.;Nishino, N.;Yokota, H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.4 no.1
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    • pp.59-65
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    • 1991
  • From the same harvest of Italian ryegrass (Lolium multiflorum, Lam.), hay(H), wilted silage(WS), pressed cake hay (PCH) and pressed cake silage (PCS) were prepared. These four preserved roughages were restrictedly fed to four goats attached with rumen fistula by $4{\times}4$ Latin square design to determine the effect of different physical and chemical properties of the roughages on the ruminal acid concentrations. Each goat was given a diet at 2% of the body weight daily in dry matter basis by separating into two equal portions. Half was given at 9 AM and the other half at 5 PM. Ruminal pH was reduced to around 5.5 within 30 minutes after feeding PCS and it was recovered above 6 in 1-2 hours after feeding. By feeding WS, ruminal pH was also reduced but never fell below 6. The two hays rather increased ruminal pH after feeding. The reduction of ruminal pH in the silage feedings was due to the high lactic acid content of the silages, because the highest ruminal lactic acid concentration was observed 30 minutes after feeding when the lowest ruminal pH was attained. While the ruminal VFA concentrations became the highest 1-2 hours after feeding. The ruminal acetic acid concentration fluctuated so much that no significant tendency was observed among the four dietary treatments. The ruminal propionic acid concentration was higher in feeding silages reflecting the initial high lactic acid concentration. As the result, acetic/propionic acid ratio was lower in the silage feedings than in hay feedings. Higher ruminal butyric acid concentration was observed in WS than in others.

A comparative study of gold UCLA-type and CAD/CAM titanium implant abutments

  • Park, Ji-Man;Lee, Jai-Bong;Heo, Seong-Joo;Park, Eun-Jin
    • The Journal of Advanced Prosthodontics
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    • v.6 no.1
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    • pp.46-52
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    • 2014
  • PURPOSE. The aim of this study was to evaluate the interface accuracy of computer-assisted designed and manufactured (CAD/CAM) titanium abutments and implant fixture compared to gold-cast UCLA abutments. MATERIALS AND METHODS. An external connection implant system (Mark III, n=10) and an internal connection implant system (Replace Select, n=10) were used, 5 of each group were connected to milled titanium abutment and the rest were connected to the gold-cast UCLA abutments. The implant fixture and abutment were tightened to torque of 35 Ncm using a digital torque gauge, and initial detorque values were measured 10 minutes after tightening. To mimic the mastication, a cyclic loading was applied at 14 Hz for one million cycles, with the stress amplitude range being within 0 N to 100 N. After the cyclic loading, detorque values were measured again. The fixture-abutment gaps were measured under a microscope and recorded with an accuracy of ${\pm}0.1{\mu}m$ at 50 points. RESULTS. Initial detorque values of milled abutment were significantly higher than those of cast abutment (P<.05). Detorque values after one million dynamic cyclic loadings were not significantly different (P>.05). After cyclic loading, detorque values of cast abutment increased, but those of milled abutment decreased (P<.05). There was no significant difference of gap dimension between the milled abutment group and the cast abutment group after cyclic loading. CONCLUSION. In conclusion, CAD/CAM milled titanium abutment can be fabricated with sufficient accuracy to permit screw joint stability between abutment and fixture comparable to that of the traditional gold cast UCLA abutment.

Esthetic treatment of gingival melanin hyperpigmentation with a Nd:YAG laser and high speed rotary instrument: comparative case report

  • Ko, Hyuk-Jin;Park, Jin-Woo;Suh, Jo-Young;Lee, Jae-Mok
    • Journal of Periodontal and Implant Science
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    • v.40 no.4
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    • pp.201-205
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    • 2010
  • Purpose: The purpose of this study was to evaluate the clinical effectiveness of and patient's satisfaction with treatment of gingival melanin hyperpigmentation with a Nd:YAG laser and a high speed rotary instrument. Methods: Three patients with melanin hyperpigmentation in the anterior parts of the gingiva were chosen for this case study. Clinical photographs were taken at the preoperative state and three patients were treated under local anesthesia. In the maxilla, the gingival deepithelization was conducted with a high speed diamond bur, whereas, in the mandible with a Nd:YAG laser. Clinical photographs were taken immediately after the procedures and at the 1st, 2nd, and 4th week to evaluate clinical color changes. A week after the procedure, the patients filled out a questionnaire about any pain or discomfort. At the 4th week after the procedure, the patients filled out questionnaires about esthetic aspects of the results of treatment. Results: In all cases, both anterior gingival areas were depigmented with satisfaction and the patients did not complain of severe pain or discomfort. At the 1st week of healing, the gingiva showed moderate to fast epithelization. Two weeks after the procedure, clinically, the gingiva showed almost complete healing. Four weeks after the procedure, there was significant improvement in gingival melanin hyperpigmentation. Conclusions: The Nd:YAG laser and the high speed rotary instruments seem to be effective for the esthetic treatment of gingival melanin hyperpigmentation.

Evaluation of digital dental models obtained from dental cone-beam computed tomography scan of alginate impressions

  • Jiang, Tingting;Lee, Sang-Mi;Hou, Yanan;Chang, Xin;Hwang, Hyeon-Shik
    • The korean journal of orthodontics
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    • v.46 no.3
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    • pp.129-136
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    • 2016
  • Objective: To investigate the dimensional accuracy of digital dental models obtained from the dental cone-beam computed tomography (CBCT) scan of alginate impressions according to the time elapse when the impressions are stored under ambient conditions. Methods: Alginate impressions were obtained from 20 adults using 3 different alginate materials, 2 traditional alginate materials (Alginoplast and Cavex Impressional) and 1 extended-pour alginate material (Cavex ColorChange). The impressions were stored under ambient conditions, and scanned by CBCT immediately after the impressions were taken, and then at 1 hour intervals for 6 hours. After reconstructing three-dimensional digital dental models, the models were measured and the data were analyzed to determine dimensional changes according to the elapsed time. The changes within the measurement error were regarded as clinically acceptable in this study. Results: All measurements showed a decreasing tendency with an increase in the elapsed time after the impressions. Although the extended-pour alginate exhibited a less decreasing tendency than the other 2 materials, there were no statistically significant differences between the materials. Changes above the measurement error occurred between the time points of 3 and 4 hours after the impressions. Conclusions: The results of this study indicate that digital dental models can be obtained simply from a CBCT scan of alginate impressions without sending them to a remote laboratory. However, when the impressions are not stored under special conditions, they should be scanned immediately, or at least within 2 to 3 hours after the impressions are taken.