• Journal of Periodontal and Implant Science
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• 제27권1호
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• pp.217-234
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• 1997

The purpose of present study is to compare the effect of treatment using $Guidor^{(R)}$ as a barrier membrane in conjunction with platelet-derived growth factor and insulin like growth factors on experimental dehiscence defects. Following the resection of premolar crowns, roots were submerged. After 12 weeks of healing period, experimental dehiscence defects of 4mm in height and 4mm in width were surgically created on the mid-facial aspect of the lower premolar roots in each of 4 adult dogs. After root planning and demineralization of the root surface with citric acid, the control groups received 4% methylcellulose gel only, the test group I received 4% methylcellulose gel and were covered by $Guidor^{(R)}$ and the test group II were treated with PDGF and IGF and 4% methylcellulose gel with $Guidor^{(R)}$ coverage. Histological and histomorphometric analysis following 8 weeks of healing revealed the following results. 1. The new bone formation showed no statistically significant difference in all groups with $0.59{\pm}0.82mm$($14.03{\pm}19.60%$) for control, $0.70{\pm}0.39mm$($16.30{\pm}9.01%$) for group I, $0.87{\pm}0.76mm$($18.74{\pm}16.03%$) for group II. 2. The new cementum formation showed no statistically significant difference in all groups with $0.54{\pm}0.48mm$($l6.38{\pm}14.57%$) for control, $0.95{\pm}0.38mm$($23.43{\pm}9.30%$) for group I, $1.01{\pm}0.75mm$($22.10{\pm}16.ll%$) for gorup II. 3. The root resorption showed statistically significant differences betweenthe control group and all test groups(p<0.05) with $2.11{\pm}0.53mm$($52.93{\pm}12.32%$) for control, $0.63{\pm}0.27mm$($15.32{\pm}7.05%$) for group I, $0.89{\pm}0.33mm$ ($19.26{\pm}7.11%$) for group II. On the bases of these results, there were no statistically difference between treatment using resorbable membrane and resorbable membrane in conjunction with PDGF and IGF in the dehiscence defects, where it was difficult to maintain space. The use of membrane seemed to be more effective in the inhibition of root resorption.

• Journal of Periodontal and Implant Science
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• 제24권1호
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• pp.64-86
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• 1994

The authors have transplanted periodontally involved roots which had been root planed into healthy and periodontally involved extraction sockets, and studied the root resorption patterns as well as its effect on new bone formation and wound healing. Alveolar bone around mandibular premolars of 6 adult dogs has been surgically removed, followed by ligation of orthodontic elastic wires for 8 weeks inducing chronic periodontal disease. After removing the crown portions, roots were extracted, and notches were made on the root surfaces discriminating healthy and periodontally involved areas using burs. Controls and experimental groups were divided as follows. Control I : Transplantation of periodontally involved root into healthy extraction sockets. Control II : Transplantation of periodontally involved root into diseased extraction sockets. Experimental group I : Transplantation of root planed roots into healthy extraction sockets. Experimental group II : Transplantation of root planed roots into diseased extraction sockets. Extraction sockets were sutured after transplantations, completely submerging the roots. Healing progress was histologically observed at 2nd, 8th, 12th, and 20th weeks, and the results were as follows ; 1. No inflammation or infection within the extraction sockets had been observed in all groups throughout the experimental period. 2. Reversal lines were observed at week 2 in all groups, clearly discriminating socket walls and new bone, and numerous blood vessels were observed in the new bone trabeculae. 3. Experimental groups showed markedly less root resorption compared to the controls at week 2, but as time progressed, severe resorptions were present in all groups. 4. Localized areas of new bone ankylosis were observed, and the rest of the areas showed collagen fiber insertion with new bone formation at its periphery. 5. No clear differences were found in healing and alveolar bone regeneration between healthy and diseased extraction sockets. 6. The amount of root resorption and ankylosis had increased up to week 8 and 12, showing ankylosis of new bone and the roots. However, no further increase in ankylosis was observed at week 20. 7. Most of the cementum on healthy roots was directly ankylosed to new bone at week, 2, and were gradually resorbed and replaced by new bone thereafter. These results appear to indicate that root planing may inhibit early root resorption of transplanted roots, but gradual replacement by alveolar bone and collagen fibers eventually occur. Condition of the roots or presence of disease in extraction sockets do not appear to make marked differences in alveolar bone regeneration process.

• 대한소아치과학회지
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• 제34권1호
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• pp.53-61
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• 2007

치아우식증이나 치주질환으로 치아를 상실한 경우 여러 가지 방법으로 수복 치료할 수 있으나 그 중에서 임플란트와 치아 이식에 대한 관심이 높아지고 있다. 최근에는 치아 이식에 대한 성공률을 높이기 위해서 치아를 형성시키고 발육시키는 과정에 관한 많은 연구가 이루어지고 있다. 치아싹 이식은 생체 내와 생체 외에서 연구되고 있고, 생체 내 이식은 쥐와 생쥐, 고양이, 개 등 여러 동물에서 시행되고 있다. 이러한 생체 내 이식은 대부분 구강 외에서 시행되고 있으며 구강 내 이식에 대한 연구는 드물다. 본 연구는 악골 내에 이식한 치아싹이 발육되고 석회화되는지 관찰하기 위하여 성숙한 흰쥐의 상악 제 1 구치를 발치하고 그 발치와에 임신 13.5일 된 태아쥐에서 모상기의 하악 제 1 구치의 치아싹을 이식하고 2, 6 개월 후 희생하여 방사선학적 그리고 조직학적으로 관찰하여 다음과 같은 결과를 얻었다. 12 개월과 6개월 동안 악골 내에 이식한 치아싹은 석회화된 치아 조직이 형성 되었고 치아 조직에서 상아질과 백악질, 치수 조직이 관찰되었으며 법랑질 공간 주변은 상피로 둘러싸여 있었다. 2. 6개월 동안 구강 상피 하방에 위치한 치아 조직은 상피로 둘러싸여 있었고 주위에 치주인대 및 결합조직이 관찰되었다. 3. 이식한 시간이 경과함에 따라 치아 형성이 진전되었으나 치아 조직은 크기가 작았고 형태학적으로 완전하지 못하였다.

• 대한소아치과학회지
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• 제39권1호
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• pp.58-65
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• 2012

치관-치근 파절은 법랑질, 상아질, 백악질이 모두 포함된 치아의 파절로, 파절선이 대부분 절단연이나 순측의 변연부 치은에서 구개측 치은열구 하방으로 사선으로 진행된다. 파절선의 위치가 치은 연상이라면 파절편의 제거 및 치은연상 수복을 시행하고, 치은 연하라면 파절면의 외과적 노출술, 교정적 정출술, 외과적 정출술을 이용한 치아의 수복이 이루어진다. 그 외에 섬유 강화형 포스트를 삽입하여 치관 수복물의 유지력을 높이고, 레진 접착 시스템을 사용하여 치관 파절편을 재부착함으로써 생물학적으로 최소한으로 침습적인 치료를 하는 방법도 있다. 만약 파절의 정도가 치은 연하로 깊은 경우 발치나 치관절제술을 이용한 치근의 유지 등을 고려할 수 있다. 본 증례는 치관-치근파절로 내원한 12세 환아로 섬유강화형 포스트를 사용하여 치관 파절편 재부착을 시행하였으며 양호한 경과를 보여 이를 보고하는 바이다.

• Restorative Dentistry and Endodontics
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• 제28권4호
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• pp.341-347
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• 2003

This study was conducted to evaluate the temperature rise on the root surface while the root canal is being obturated using continuous wave of condensation technique. Maxillary central incisor was prepared for repeated canal obturation. Ten thermocouples (Omega Engineering Inc., Stanford, USA) were placed at 1 mm increment from the anatomical root apex. The real temperature of Buchanan plugger was recorded before insertion into the root canal. The root canal was obturated with continuous wave of condensation technique as described by Buchanan and the root surface temperature was recorded during obturation at $150^{\circ}C,{\;}200^{\circ}C,{\;}250^{\circ}C{\;}and{\;}300^{\circ}C$ temperature settings of System B HeatSource (Model 1005, Analytic technologies, Redmond, WA, USA). After completion of the temperature recording, the dentinal-cementum thickness at each sites was measured. The data were analyzed using one-way ANOVA followed by Scheffe's test and linear regression test. The results were as follows. 1. When the temperature was set at $150^{\circ}C,{\;}200^{\circ}C,{\;}250^{\circ}C{\;}and{\;}300^{\circ}C$ on the digital display of System B HeatSource, the real temperature of the plugger at the 1mm point from the tip revealed $130.82{\pm}2.96^{\circ}C,{\;}158.00{\pm}5.26^{\circ}C,{\;}215.92{\pm}6.91^{\circ}C{\;}and{\;}249.88{\pm}3.65^{\circ}C$ respectively. 2. The position of 8 mm from the anatomical apex showed the highest temperature increase at each temperature settings and it was significantly higher than those of other positions (p<0.0l). The temperature rise was constantly increased toward coronal portion from apex of the root. 3. The maximum temperature increase on the root surface was $2.37{\pm}0.09^{\circ}C{\;}at{\;}150^{\circ}C{\;}setting,{\;}3.11{\pm}0.12^{\circ}C{\;}at{\;}200^{\circ}{\;}setting,{\;}3.93{\pm}0.09^{\circ}C{\;}at{\;}250^{\circ}C{\;}setting{\;}and{\;}5.69{\pm}0.15^{\circ}C{\;}at{\;}300^{\circ}C$ setting respectively. These results suggest that it be relatively kind to the supporting tissues of the root that the root canal is obturated using continuous wave of condensation technique at $150^{\circ}C,{\;}200^{\circ}C,{\;}250^{\circ}C{\;}and{\;}300^{\circ}C$ temperature settings on digital temperature display of System B HeatSource.

• Restorative Dentistry and Endodontics
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• 제17권2호
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• pp.307-330
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• 1992

The aim of this study was to investigate the physical properties of visible light curing Glass Ionomer cement for restorative esthetic filling. The control group was the autopolymerizing GC Fuji II Glass Ionomer cement (2.2: 1 P/L ratio) and the experimental groups were made by following procedure. To induce the polymerization by visible light, the powder of GC Fuji II GI cement and the liquid of Vitrabond for base & liner were mixed in an amalgam capsule with 2.5:1, 3.0:1, 3.5:1 P/L ratio (% wt/wt). After fabrication of specimens, compressive strength, fracture toughness ($K_{IC}$) Scanning Electron Microscope and X-ray Diffraction, water-leachable content, marginal leakage and surface roughness were studied. The results were as follows: 1. Only experimental No. 1 group (visible light curing) showed less compressive strength than control group 1 hour after curing. Strength was increased with aging in all groups, so the compressive strength of light curing groups was no less than that of autopolymerizing group after 3 weeks. 2. Experimental No.3 group (visible light curing) was inferior to No.2 group (visible light curing) in fracture resistance but light curing groups were more resistant to fracture than autopolymerizing group and showed ductile fracture pattern as compared with the brittle fracture pattern of autopolymerizing group. 3. From scanning electron microscopic image, various sized unreacted powder particles, surrounded by silica gel, were embedded in polysalt matrix. Light curing groups showed little crack and more dense unreacted particles than autopolymerizing group. 4. From X-ray diffraction analysis, GC Fuji II Glass Ionomer cement powder and all groups showed glassy appearance but light curing groups seemed to be more intensive in crystaline than autopolymerizing group. S. The most significant dissolution was shown in early setting period in all group. Light curing groups were dissolved less than autopolymerizing group. 6. Marginal leakage was not different significantly in case of cavity margin composed of same tooth structure (ex. only enamel margin, only dentin margin) but much more leakage was shown in dentin/cementum margin than enamel margin. In only case of only enamel margin, light curing groups were superior to autopolymerizing group. 7. All groups showed relatively smooth surface, which irregularity was less than $1{\mu}m$. Light curing groups were smoother than autopolymerizing group.

• Restorative Dentistry and Endodontics
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• 제30권5호
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• pp.355-362
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• 2005

본 연구는 복합레진을 광조사하기 전과 광조사한 후에 표면 전색제인 Biscover를 적용하여 이들에 대한 변연 미세누출을 평가하고, 또한 표면 전색제를 적용하지 않는 복합레진 수복물과의 미세누출 차이를 비교하기 위하여 시행하였다. 30개의 발거된 대구치의 협면 치경부에 5급 와동을 형성하여 다음과 같이 3개의 군으로 분류하였다; 대조군은 복합레진 표면에 Biscover를 적용하지 않은 군, 1군은 복합레진을 광조사하고 마무리한 후 Biscover를 적용한 군, 2군은 복합레진을 광조사하지 않고 Biscover를 적용한 군. 각 군의 시편은 실온의 증류수에 48시간 동안 보관한 후 $5^{\circ}C$와 $55^{\circ}C$에서 1,000회의 열 순환을 시행하고 2% methylene blue용액에 4시간 동안 침적시켰다. 20배율의 광학 입체현미경 하에서 각 군의 교합면측과 치은측 변연의 색소침투 정도를 관찰하여 미세누출 점수를 얻은후, 각군 간의 유의성을 검정하여 다음과 같은 결과를 얻었다. 1. 2군은 1군보다 교합면측과 치은측 변연 모두에서 높은 미세누출을 보였으나 통계학적으로 유의한 차이는 없었다 (p > 0.05). 2. 대조군은 교합면측 변연에서 1군과 2군보다 약간 높은 미세누출을 보였으며 , 치은측 변연에서 1군보다 약간 높게 그리고 2군과 비슷한 미세누출을 보였다 (p > 0.05). 3. 대조군과 2군은 교합면측 보다 치은측 변연에서 통계학적으로 높은 미세누출을 보였으며 (p < 0.05), 1군은 교합면측과 치은측의 변연 미세누출 간에 통계학적인 차이를 나타내지 않았다 (p > 0.05). 본 연구를 종합하면, Biscover는 중합된 복합레진 표면에 적용할 경우 치은측 변연의 미세누출을 감소시키는데 효과적이었다.

• Restorative Dentistry and Endodontics
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• 제26권4호
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• pp.296-306
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• 2001

The purpose of this study was to observe the effect of dexamethasone and osteogenic protein-1(BMP-7) on bone, cementum and periodontal tissue regeneration. A total of 60 Sprague-Dawley white female mice were selected and beta-APN was used for five days to extract the maxillary first molar a traumatically. After the extraction of the teeth, the mesiobuccal root canal was filled with Caviton$^{\circledR}$. The teeth were etched with citric acid for 1 min and coated with one of four different experimental solutions : DEX(500nM/ml), DEX(1000nM/ml), OP-1(100$\mu\textrm{g}$/ml) and OP-1(500$\mu\textrm{g}$/ml) for three minutes depending on the group. All teeth were then replanted under microscope. All replantation procedures were done within 30 minutes. Teeth that were replanted after 30 minutes of bench dry only was used as positive control. All animals were sacrificed at 3 weeks following replantation and histologic observtion was done. The results were as follows ; 1. Active root resorption rate was decreased by the order of OP-1(500$\mu\textrm{g}$/ml), DEX(1000nM/ml), OP-1(100$\mu\textrm{g}$/ml), and DEX(500nM/ml). There was statistically less root resorption in OP-1 (500$\mu\textrm{g}$/ml) and DEX(1000nM/ml) group(P<0.05). 2. The group with higher concentration of dexamethasone(1000nM/ml) had statistically more bone union compared to positive control group(P<0.05),but there were no significant differences among four experimental groups. 3. OP-1(500$\mu\textrm{g}$/ml) and DEX(1000nM/ml) groups showed less degree of inflammation compared to the OP-1(100$\mu\textrm{g}$/ml). DEX(500nM/ml), and positive control group (P<0.05). In conclusion, the group with higher concentration of OP-1 had the best results on root resorption, bone ankylosis and anti-inflammatory effects compared to the other experimental groups, but a long-term study is also necessary to evaluate the exact pharmacological effects of the drugs in the future.

• 대한치과교정학회지
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• 제39권3호
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• pp.185-198
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• 2009

치아 유착은 손상에 의해서 치조골과 상아질 또는 백악질이 유합된 상태로, 외상, 내분비 질환, 쇄골 두개 이형성증등의 선천성 기형 또는 원인 불명의 맹출 장애 등이 원인으로 알려져 있다. 유착 치아로 인해 인접치의 경사, 공간 상실 및 대합치의 정출이 나타날 수 있고, 성장기 아동에서 유착이 발생한 경우 치조골의 발육 부전을 야기할 수 있으며, 특히 상악 전치부에 이환되면 심각한 심미적 문제를 초래하게 된다. 따라서 유착이 의심되면, 병력 청취와 타진 및 방사선 사진 상의 치근막 공간 평가, 또는 가장 직접적이고 확실한 방법인 교정력을 직접 적용해 보는 방법을 통해 정확한 진단을 내려야 한다. 통상적으로 치료는 유착된 치아의 발거, 자가 치아이식, 외과적 탈구, 수술적 방법을 통한 재위치술 등을 선택하게 된다. 그 중, 수술적 방법을 통한 재위치술은 유착치의 발거 시 상당한 골소실이 예상될 때 시행할 수 있으며, 단일치아 골절단술과 치조골 신장술이 대표적이다. 본 보고에서는 이러한 수술적 방법으로 상악 전치부의 유착치를 심미적으로 치료한 증례를 소개하고자 한다.

• Journal of Periodontal and Implant Science
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• 제32권1호
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• pp.89-112
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• 2002

The earliest reports of the use of electrical energy to directly stimulate bone healing seem to be in 1853 from England, the techniques involved the introduction of direct current into the non-united fracture site percutaneously via metallic needles, with subsequent healing of the defect. One endpoint of the periodontal therapy is to generate structure lost by periodontal diseases. Several procedural advances may support regeneration of attachment, however, regeneration of alveolar bone does not occur consistently. Therefore, factors which stimulate bone repair are areas for research in periodontal reconstructive therapy. Effects of cytokines or growth factors on bone repair are examples of such areas. Another one is electrical current which occurs in bone naturally, so that such bone may be particularly susceptible to electrical therapy. The purposes of this study were to observe the effects of electrical stimulation on the normal periodontium, to determine whether the electricity is the useful means for periodontal regeneration or not. Forty rats weighted about 100 gram were used and divided into 4 groups, the first group, there was no electrical stimulation with the connection of electrodes only. In the second group, there was stimulated by the 10 mA during 10 minutes per a day, in the third group was stimulated by the 25 mA , and the fourth by the 50 mA. At 3, 5, 10 and 15 days post-appliance , two rats in each group were serially sacrificed. and the maxillae and the mandible processed to paraffin, and the specimens were prepared with Hematoxylin-Eosin stain for the light microscopic evaluation. The results of this study were as follows : 1. There was the distinct reversal line on the lingual alveolar crest, whereas a little changes in the labial alveolarcrest to the duration and amount of currents. 2. In 50 mA group, the cells were highly concentrated at the apex of anterior teeth, and was observed the necrotic tissue. In posterior root apex, the hypercementosis was appeared, and newly formed cementum layer has been increased continuously with the time. 3. The periodontal ligament fiber and Sharpey's fiber were arranged in order, and the bone trabeculae were increased as the experiment proceeded by, relatively the bone marrows were decreased. 4. In the pulp tissue, the blood vessels were increased with blood congestion in the experimetal specimens remarkably, and the dentinal tubules were obstructed . 5. The osteoblasts in alveolar bone proper had been showed highly activity, and also observed the formation of bone trabeculea. In the conclusion, it was suggested that the electrical stimulation has influence on the periodontium and the pulp tissue. However, there might be the injurious effects.