• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권6호
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• pp.591-601
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• 2000

The objective of this study was to find out whether the unilateral distraction of mandible has an influence on temporomandibular joint and if it does, how significant the influence is. Four beagle dogs were used in this study. Each dog had two implants placed into the left mandible. The mandible was distracted for 14days with an distraction device as an amount of 0.75mm, twice per day after osteotomy between two implants. Each animals were sacrificed at the second, fourth, sixth and eighth week after the total distraction amount of 10.5mm were gotten. Upon embedding and staining, the specimens were evaluated with a light microscope. The results were as follows. 1. For the second week group, the articular cartilage and osteoid seam of temporal bone and condyle were relatively well maintained. There were not any significant differences between distraction side and non distraction side. 2. For the fourth week group, the periosteal reaction was activated and the articular cartilage and osteoid seam of temporal bone and condyle were severely thickened - especially at posterior portion of distraction side. This findings revealed that the unilateral distraction forces has more influence on distraction side than on non distraction side, and on posterior portion than on anterior portion. 3. For the sixth and eighth week group, the thickness of meniscus in distraction side gradually recovered to the initial level. The thickened articular cartilage and osteoid seam of temporal bone and condyle were decreased in distraction side and showed relatively stable in non distraction side. From this results, we suggest that several considerations are required such as using an occlusal splint, maintaining the stability of bone distraction device and evaluating bone distraction rate to minimize the damages of temporomandibular joint tissues in early stage of distraction side.

• Journal of Periodontal and Implant Science
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• 제25권2호
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• pp.301-320
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• 1995

The purpose of this study was to evaluate a new biodegradable membrane - atelocollagen as a guided tissue regeneration barrier on the dehiscence defects adjacent to the dental implants. 3 beagle dogs were selected for this study and all the mandibular premolars($P_1,P_2,P_3&P_4$) were extracted. Twelve weeks after the extraction, the edentulous ridges were formed to be placed the titanium plasma-sprayed IMZ implants. Four implant osteotomies were performed on each side of the mandible. The osteotomies were placed facially in the edentulous ridges to approximate an actual dehiscence defect as closely as possible, The standardized dehiscence defects were created 3 mm in width and 4 mm in height by osteotomy. A total 24 implants were placed. e-PTFE, ateloco11agen and $Collatape^{(R)}$ were placed to cover the defects and the one defect served as a control, not covered any membrane. By random selection, three dogs were sacrificed at 2 weeks, 4weeks and 8 weeks after fixation with 3% glutaraldehyde. A week before sacrificing, 8-week dog was infused intravenously with oxy-tetracycline 30mg/kg. The left mandibular blocks were used for full decalcified histologic preparation and the right mandibular blocks were selected for undeca1cified preparation, At 2 weeks, the regenerated bone of e-PTFE and atelocollagen groups appeared to be more dense than other groups and the percentage of bone defect fill was highest for e-PTFE and follwed by ateloco1lagen group. However, the $Collatape^{(R)}$ and control groups showed a little new bone formation. $Collatape^{(R)}$ was almost degraded within 2 weeks. At 4 weeks, the regenerated new bone were much greater and denser than at 2 weeks for e-PTFE and ateloco11agen group. Although a part of atelocollagen bagan to be degraded at the margin and surrounded by foreign body giant cells related to foreign body reaction, it was generally intact and the regenerated new bone was shown much more than at 2 weeks. The amount of new bone in $Collatape^{(R)}$ and control groups at 4 weeks were similar to that of 2 weeks group. At 8 weeks, the regenerated bone was matured and observed along the implant fixture. Direct new bone formation and calcium deposits beneath the e-PTFE were observed. No further bone growth was seen in the $Collatape^{(R)}$ and control groups. In reflected fluoromicrcocopic observation, the osteogenic activity was pronounced between e-PTFE membrane and the old bone. High osteogenic activity was also observed in atelocol1agen group. This study suggested that the ateloco11agen as well as e-PTFE could be used for guided tissue regeneration on dehiscence defects adjacent to the dental implants. But the $Collatape^{(R)}$ was completely resorbed within 2 weeks and was not a suitable membrane for guided bone regeneration.

• Journal of Periodontal and Implant Science
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• 제34권1호
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• pp.127-138
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• 2004

Background: Crestal bone loss known as saucerization is a frequently observed phenomenon. Recent studies have shown that implants with micothreaded crest module reduced the force concentration in the crestal region thus resulting in no or reduced crestal bone loss. This study presents a clinical, histologic, and histometric evaluation of implants with microthreaded crest module and SLA surface. Methods: The implants were placed in the mandible of 5 beagle dogs weighing 10-15kg. Four premolars were bilaterally extracted 8 weeks prior to implant placement. Mucoperiosteal flap was elevated and drilling with increasing diameter was performed under saline irrigation. After countersinking 2 implants were placed in each side resulting in 4 implants per dog. Healing period of 8 weeks was allowed before sacrificing the animals. Histologic preparation was performed for histologic and histometric analysis. Bone to implant contact as well as percentage of bone area inside threads were measured. T-test was used for statistical analysis with pvalue p<0.05. Results: 1. Healing was uneventful without any cover screw exposure. New bone formation around the implants was observed without any inflammatory infiltration. 2. Bone to implant contact in the microthread and thread were 43.90 ${\pm}$ 20.30 %, and 53.19 ${\pm}$ 20.97 % respectively. The overall bone to implant contact was 48.54 ${\pm}$ 20.95 %. 3. Percentage of bone area inside threads were 54.43 ${\pm}$ 10.39 %, and 38.44 ${\pm}$ 16.44 % for the microthread and thread respectively. There was statistically significant difference(p<0.05). The overall percentage of bone area inside threads was 46.67 ${\pm}$ 15.68 %.

• Journal of Periodontal and Implant Science
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• 제33권2호
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• pp.301-310
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• 2003

The purpose of this study is to evaluate the biocompatibility and the biorsorbability of several types of calcium polyphosphate made through change of manufacturing process for 12 month. To solve limitation of calcium phosphate, we developed a new ceramic, Calcium Polyphosphate(CPP), and report the biologic response to CPP in extraction sites of beagle dog. Porous CPP blocks were prepared by condensation of anhydrous $Ca(H_2PO_4)_2$ to form non-crystalline $Ca(PO_3)_2$ and then milled to produce CPP powder. CPP powder, CPP block, and CPP granules added with $Na_2O$ were implanted in extraction sockets and histologic observation were performed at 12 months later. Like 3 months results, histologic observation at 12 months revealed that CPP matrix were mingled with and directly apposed to new bone without any adverse tissue reaction, CPP powder show direct bony contact, but new bone formation and fibrous tissue encapsulation showed in CPP block. 10% $Na_2O$ CPP granules show more inflammatory cells infiltration around graft materials compared at 3 month, but 15% $Na_2O$ CPP granules show less. This result revealed that regardless of addition of $Na_2O$, CPP had a high affinity for bone and had been resorbed slowly. From this results, it was suggested that CPP is promising ceramic as a bone substitute and addition of $Na_2O$ help biodegradation but optimal concentration of $Na_2O$ and other additive component to increase degradation rate should be determined in further study.

• 한국임상수의학회지
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• 제22권1호
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• pp.21-25
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• 2005

This study was performed to assess therapeutic effect of the tibial plateau leveling osteotomy (TPLO) in dogs with experimentally transected cranial cruciate ligaments (CrCL). Nine healthy adult Beagle dogs were transected left CrCL under general anesthesia. The dogs were assigned to TPLO and non-TPLO control groups. The TPLO procedures for correcting the CrCL rupture in the left stifle of dogs were performed under sterile conditions. Before TPLO procedures, all dogs were screened by orthopedic and radiographic examinations. Dogs were lameness free for the previous three months, and when examined at the walk and trot on a hard surface, in a straight line and on a circle. Lateral and craniocaudal radiographs were done to confirm the soundness of the both knee joint in dogs and not detectable lesions were diagnosed. The dogs were intravenously injected with a 10 mci/kg of 99mTechnetium-methylene diphosphonate (99mTc-MDP) under general anesthesia. Scintigraphs were obtained using a large field of view gamma camera equipped a parallel-hole, low-energy about 3 hours after intravenous injection of 99mTc-MDP. Before CrCL transection and 4, 8, and 12 weeks after the procedures, scintigraphy were conducted. Bone uptake of the left stifle joint increased after the procedures in all dogs. When the bone uptake from the TPLO procedure was compared with that of the control, there was a significant difference (p < 0.05). At 12 weeks after the TPLO procedure, the dogs showed normal anatomical posture and gait. It is concluded that TPLO procedure was effective in reconstruct of the stifle joint in dogs with CrCL rupture.

• 한국임상수의학회지
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• 제28권2호
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• pp.211-218
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• 2011

개에서 많은 주사용 마취제가 있고 그 부작용을 줄이기 위해 다양한 약물들을 혼합하여 사용한다. 개에서 medetomidine-midazolam-ketamine (MMK) 합제에 대한 마취효과를 알아보고, 이 합제에 대한 atipamezole과 yohimbine의 길항효과를 비교하였다. 18마리 수컷 비글견을 사용하였고, 모든 개에서 medetomidine (0.04 mg/kg), midazolam (0.2 mg/kg) 및 ketamine (5 mg/kg)을 근육주사하고, 20분 후 atipamezole (0.24 mg/kg, MMKA), yohimbine (0.2 mg/kg, MMKY) 또는 생리식염수(0.1 ml/kg, MMK)를 정맥주사하였다. 유도 및 회복시간, 진정 및 진통점수, 심박수, 혈압, 직장온도, 호흡수, 동맥혈액가스를 측정하였다. 평균마취, 흉와, 기립 및 보행시간은 MMKA와 MMKY군에서 MMK군보다 유의성있게 짧았다. 그러나 MMKA군과 MMKY군 간의 유의적인 차이는 없었다. 모든 군에서 MMK 투여는 개에서 만족스런 진정 및 진통을 일으켰다. 그러나 atipamezole이나 yohimbine 투여 후 자세점수 및 유해자극반응은 MMK군에 비해 MMKA나 MMKY군에서 유의성있게 감소하였다. 본 실험 결과 MMK는 양호한 진정 및 마취효과를 나타냈고, atipamezole과 yohimbine은 개에서 MMK 마취를 길항하는 데 안전하고 효과적으로 사용될 수 있을 것으로 사료된다.

• 한국임상수의학회지
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• 제32권2호
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• pp.162-167
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• 2015

좌심실의 용적과부하와 심할 경우 심근 기능부전을 일으키는 질병에서 Tei index는 심근기능을 평가하는데 있어 비교적 측정이 쉽고 재현율이 양호하다고 보고된 심초음파 측정 요소이다. 본 연구에서는 정상 및 퇴행성 이첨판 질환이 있는 개에서 조직도플러와 펄스파 도플러를 통해 Tei index 값을 측정하고, 다른 초음파평가지표와 비교평가하였다. 정상 개에서 Tei index 측정을 위해 심혈관계에 이상이 없는 13마리의 비글견을 사용하였으며, 이첨판 역류를 진단받은 환자 31마리를 환자군으로 하여 각각의 환자는 임상증상에 따라 세 개의 그룹으로 나뉘어 각 측정치를 비교하였다. 본 실험 결과에서 대부분의 측정항목들이 좋은 신뢰도를 보였으며, Tei index의 경우 조직도플러를 통한 Tei index가 펄스파 도플러에 비해 좀 더 높은 신뢰도를 나타내었다. 본 실험에서 정상 개에서 Tei index는 조직도 플러의 심실외벽과 중격에서 각각 $0.58{\pm}0.07$, $0.60{\pm}0.07$로 측정되었다. 조직도플러 검사 결과 중격과 좌심실벽 지점간에는 Tei index의 차이가 나타나지 않았다. 펄스파도플러를 통해 측정한 Tei index는 조직도플러를 통해 측정한 Tei index에 비해 유의성 있게 낮게 측정되었다. 정상 및 퇴행성이첨판 질환이 있는 환자군에서 Tei index는 두 가지 측정 방식 모두에서 이첨판 역류의 임상증상에 따라 그룹별로 유의적으로 증가하는 것으로 나타났다. 따라서, Teiindex는 이첨판 역류가 있는 개에서 좌심실 기능 저하를 반영하는 유용한 검사 요소로 생각된다.

• Journal of Periodontal and Implant Science
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• 제27권1호
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• pp.61-78
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• 1997

PDGF-BB has been recognized as a highly potential growth factor for guided tissue regeneration in periodontal defect. This study carried out histologic and histometric evaluation of $200ng/cm^2$ PDGF-BB loaded bioresorbable membrane made from polyglycolic and polylactic acid. It was tested for its biocompatibility, ability to prevent epithelial downgrowth and amount of periodontal regeneration. Without membrane and PDGF-BB unloaded bioresorbable membrane were used as control. Healthy six beagle dogs were used. Each dog was anesthetized and buccal flaps were reflected in the mandibular and maxillary premolar areas. Buccal alveolar bone between the mesiobuccal and distobuccal line angles was surgically removed on the lower 2nd and 4th premolar in mandible, 2nd premolar in maxilla, to a level 4mm apical to the cementoenamel junction with creating a Class II buccal furcation defect for available space. Care was taken not to remove the root cementum layer and rubber impression materials were placed over each surgically created defect. Flaps were repositioned and sutured. Reconstructive surgery was performed 1 month after defect preparation. PDGF-BB loaded membranes and controls were randomly placed on maxillary 2nd premolars and mandibular 2nd and 4th premolars. Plaque control regimen was instituted with daily brushing with a 0.1% chlorhexidine digluconate during experimental periods. The animals were sacrificed 2 and 5 weeks after surgery and undecalcified specimens were prepared for histologic evaluation. The degree of coronal regrowth of new bone, new cementum and the amonut of new bone areas formed on the defected area of the PDGF-BB loaded membrnae turned superior to without membrane and drug unloaded membrane. Experimental membrane could prevent the epithelial downgrowth irrespective of drug loaded or not and showed good biocompatiblity, These results implicated that PDGF-BB loaded bioresorbable membrane could be highly useful tool for guided tissue regeneration of periodontal defects.

• 한국임상수의학회지
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• 제25권5호
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• pp.359-362
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• 2008

본 연구는 개 빈맥에 대한 내관 (PC06) 및 심수 (BLl5)자침의 효과를 입증하고자 실시하였다. 총 18두의 비글견을 대조군 (6두), PC06 군 (6두) 및 BL15 군 (6두)로 각각 나누었다. 빈맥은 glycopyrrolate를 근육주사하여 유발하였다. 대조군은 아무런 처치를 하지 않았으나, 실험군은 glycopyrrolate 투여와 동시에 각각 PC06 및 BL15에 20분간 유침하였으며, R-R 간격의 변화 및 호흡수의 변화를 측정하였다. PC06군과 BL15군에서의 R-R 간격은 대조군에 비하여 유의성 있는 증가를 나타내었으며, BL15군의 R-R 간격은 PC06군에 비하여 유의성 있는 증가를 나타내었다. PC06군의 호흡수는 대조군과 비슷한 경향을 나타냈으나 BL15군은 대조군 및 PC06군에 비하여 유의성 있는 감소를 나타내었다. 결과적으로, PC06 및 BL15의 자침은 개 빈맥의 회복에 도움이 되며, BL15가 PC06보다 효과적인 것으로 판단된다.

• 생명과학회지
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• 제18권3호
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• pp.414-417
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• 2008

본 증례는 4년령의 암컷 비글종에서 발생한 것으로 점진적인 안구돌출증을 비롯하여 왼쪽 하안구 부속기에 발생한 직경 1.4 cm 의 종양을 가지고 있었다. 종양의 병리조직학적 검경에서 증생된 종양 세포들이 소엽 및 섬유성 격벽으로 구분되는 관통상의 구조를 나타내고 있었다. 잘 분화된 피지선은 다양한 크기의 소엽을 형성하고 있으며 비만세포 및 단핵 염증세포의 침윤이 관찰되었다. 관강 내에는 이러한 관성구조의 정점부위에서 탈락되어 나온 호염성 불질이 관찰되었으며 일부 관성구조는 경도의 화생을 나타내고 있었다. 조직면역염색에서 세포집단은 ${\alpha}-SMA$와 vimentin에 양성 반응을 나타내었다. 따라서 본 원발성 종양은 안검에서 발생한 내검판선 및 외검판선 유래의 선암종으로 진단되었으며 침윤되고 있는 안구내 종양은 악성 혼합종으로 진단되었다.