• 대한치과교정학회지
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• 제20권3호
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• pp.447-462
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• 1990

The objective of this experiment is to observe structural differences in the othodontic movement of vital (control group) and devitalized (experimental group) teeth in the mongrel dogs. The 5 utilized dogs in this experiment were approximately 1 year of age and their average weight was about 12 Kg. Endodontic therapy was performed on the 2nd premolars in upper & lower jaws of each animal under the general anesthesia by intravascular injection of 25mg/kg of pentobarbital sodium. The canals of the teeth were obturated by using gutta percha in conjunction with root canal sealer (AH26 Densply). One of the roots in the 2nd premolars was hemisected to make an extraction space for the devitalized teeth to be moved. The edgewise technique was employed for the movement of the teeth. Orthodontic models and intraoral roentgenograms were taken before and after orthodontic tooth movement. The open coil springs (.010 x .040) were used at interbraket space in order to provide equal forces (75gm) between the teeth in each arch wire. After 13 weeks of active orthodontic tooth movement, dogs were sacrified and the experimental results w ere examined through the intraoral radiography, microscopic examination and scanning electromicroscopic examination at the root sulfate. From the results of the study, the following conclusions may be drawn: The root resolution and cemental deposition were observed within the pressure and tension site in both group. 2. The root resorbed lacunae were observed in the cementum and/or into the dentin in both group. 3. The prominent osteoblastic activities were observed on the alveolar margin in the tension site in both group. 4. A few of blood vessels were observed in the pressure site, but also lots of blood vessels were observed in the tension site especially in the periphery of the alveolar bone in both group. 5. In the pressure site, resorbed lacunae were formed with deep and narrow cavity in the control group; the shallow and wide cavity in the experimental group. 6. In the pressure site, the repaired cementum or cementoid tissue was lined on cementum in the experimental group, but not in the control group. 7. There was no significant difference between external root resolution of endodontically and vital teeth when both were subjected to orthodontic forces.

• Journal of Periodontal and Implant Science
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• 제36권1호
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• pp.27-37
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• 2006

Although the main purpose of periodontal treatment to regenerate is the complete regeneration of periodontal tissue due to periodontal disease, most of the treatment cannot meet such purpose because healing by long epithelial junction. Therefore, diverse materials of resorbable and non-resorbable have been used to regenerate the periodontal tissue. Due to high risk of exposure and necessity of secondary surgical procedure when using non-resorbable membrane, guided tissue regeneration using the resorbable membrane has gain popularity, recently. However, present resorbable membrane has the disadvantage of not having sufficient time to regenerate date to the difference of resorption rate according to surgical site. Meanwhile, other than the structure stability and facile manipulation, acellular dermal matrix has been reported to be a possible scaffold for cellular proliferation due to rapid revascularization and favorable physical properties for cellular attachment and proliferation. The purpose of this study is to estimate the influence of acellular dermal matrix on periodontal ligament, cementum and alveolar bone when acellular dermal matrix is implanted to 1-wall alveolar bone defect. 4 dogs of 12 to 16 month old irrelevant to sex , which below 15Kg of body weight, has been used in this study. ADM has been used for the material of guided tissue regeneration. The 3rd premolar of the lower jaw was extracted bilaterally and awaited for self-healing. subsequently buccal and lingual flap was elevated to form one wall intrabony defect with the depth and width of 4mm on the distal surface of 2nd premolar and the mesial surface of 4th premolar. After the removal of periodontal ligament by root planing. notch was formed on the basal position. Following the root surface treatment, while the control group had the flap sutured without any treatment on surgically induced intrabony defect. Following the root surface treatment, the flap of intrabony defect was sutured with the ADM inserted while the control group sutured without any insertion. The histologic specimen was observed after 4 and 8 weeks of treatment. The control group was partially regenerated by periodontal ligament, new cementum and new alveolar bone. the level of regeneration is not reached on the previous formed notch. but, experimental group was fully regenerated by functionally oriented periodontal ligament fiber. new cementum and new alveolar bone. In conclusion, we think that ADM seems to be used by scaffold for periodontal ligament cells and the matrix is expected to use on guided tissue regeneration.

• Journal of Periodontal and Implant Science
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• 제30권1호
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• pp.167-180
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• 2000

The present study evaluated the effects of guided tissue regeneration using biodegradable membrane, with and without calcium-phosphate thin film coated deproteinated bone powder in beagle dogs. Contralateral fenestration defects(6 × 4 mm) were created 4 mm apical to the buccal alveolar crest on maxillary canine teeth in 5 beagle dogs. Ca-P thin film coated deproteinated bone powder was implanted into one randomly selected fenestration defect(experimental group). Biodegradable membranes were used to provide bilateral GTR. Tissue blocks including defects with overlying membranes and soft tissues were harvested following a four- & eight-week healing interval and prepared for histologic analysis. The results of this study were as follows. 1.......The regeneration of new bone, new periodontal ligament, and new cementum was occurred in experimental group more than control group. 2.......The collapse of biodegradable membranes into defects were showed in control group and the space for regeneration was diminished. In experimental group, the space was maintained without collapse by graft materials. 3........In experimental group, the graft materials were resorbed at 4 weeks after surgery and regeneration of bone surrounding graft materials was occurred at 8 weeks after surgery. 4.......Biodegradable membranes were not resorbed at 4 weeks and partial resorption was occurred at 8 weeks but the framework and the shape of membranes were maintained. No inflammation was showed at resorption. In conclusion, the results of the present study suggest that Ca-P thin film coated deproteinated bone powder has adjunctive effect to GTR in periodontal fenestration defects. Because it has osteoconductive property and prohibit collapse of membrane into defect, can promote regeneration of much new attachment apparatus.

• 대한소아치과학회지
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• 제8권1호
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• pp.55-63
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• 1981

The purpose of this study is to observe the effect of formocresol and glutaraldehyde to tooth germs and periapical tissues after perforation of interradicular portion of pulpal floor and application of physiological saline solution in control groups, formocresol and glutaraldehyde in experimental groups. The following results were obtained 1. In control groups, normal healing processes were seen, and, on the sixteenth day, the epithelization of injured areas was completed. Inflammatory reactions were limited to the injured surface, and the underlying alveolar bone were normal and successive tooth germs were normal. 2. In both formocresol groups and glutaraldehyde groups, tissue reactions were identical. Inflammatory reactions were slightly compared with control groups, but the surface epithelizations were delayed compared with control group. 3. In both formocresol and glutaraldehyde groups, necrosis was seen in superficial tissue of bone marrow, and, at 24th day, center area of bone marrow on the successive tooth germs were losed and replaced with connective tissue, and superficial soft tissue of the injured area was connected with soft tissue on the successive tooth germ. In remaining alveolar bone, osteoclastic reaction was remarkable. 4. In both formocresol and glutaraldehyde groups, there is no injury to the successive tooth germs. 5. In both formocresol and glutaraldehyde groups, periodontal membrane was normal, but the partial resorption of cementum and dentin near the injured area were seen.

• 대한치과교정학회지
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• 제1권1호
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• pp.15-20
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• 1970

저자는 흰쥐 27수의 하악제일대구치를 교정용 고무선으로 이동시킨후, 이동의 초기에 나타나는 치수의 반응을 조직학적 방법으로 관찰하는 것을 연구목적으로 하였다. 30 Gm부터 120 Gm까지의 힘을, 12수는 3일간, 15수는 7일간, 각 실험치아에 부여하였다. 관찰결과는 다음과 같았다. 1. 치수조직의 주변화는 치수혈관의 순환장애와 조상아세포의 공포형상으로 나타났다. 2. 적용시킨 힘의 증가에 따라서 상기 조직변화의 범위가 확대되었다. 3. 기외에 치근의 상아질과 백악질의 부분적 흡수도 볼 수 있었다.

• 치과방사선
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• 제25권1호
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• pp.159-170
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• 1995

Few cases of florid osseous dysplasia has been described as a condition that characteristically affects the jaws. It usually manifests as multiple radiopaque masses distributed throughout the jaws. Confusion exists about the relationship of florid osseous dysplasia, gigantiform cementoma, chronic sclersing osteomyelitis, sclerosing osteitis or multiple enostosis. Authors experienced a case of florid osseous dysplasia of the jaws in 52-year-old female on the basis of clinical, radiographic and histopathologic findings. The characteristic features are as follows : 1. In clinical examination, there was no clinical sign and symptoms except extracted area. And there was no facial asymmetry. 2. Radiograms show round or lobular dense radiopaque masses surrounded by radiolucent bands in lower molar teeth area bilaterally. And slight increased radiopacities in maxillary molar teeth area bilaterally. There was no expansion or thinning of buccal and lingual cortical bones. There is no displacement or resorption of involved teeth. In right side of mandible, mandibular canal is displaced inferiorly due to mass. 3. Photomicrograms show densely mineralized sclerotic acellular masses with empty lacunae. Pattern is suggestive of cementum, although it could be considered sclerotic bone. In the periphery, lesion consisting of moderately cellular fibrous tissue in which globular calcified products are deposited.

• Restorative Dentistry and Endodontics
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• 제25권2호
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• pp.159-169
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• 2000

The purpose of this study was to examine the tissue response to experimental furcation perforations immediately treated with Super EBA, Ketac Silver, MTA and Emdogain using surgical microscope. Forty experimental furcation perforations were created in the mandibular and maxillary premolars and molars of 4 adult dogs and immediately repaired with experimental materials. The animals were sacrificed after 16 weeks and radiographic and histologic results were evaluated. The results were as follows. 1 All materials tested in this experiment revealed a certain degree of extrusion of the filling materials and infiltration of inflammatory cells into the periodontal space. Except MTA group, epithelial down-growth of the surrounding gingiva was found in all experimental groups. 2. Both Ketac Silver and Emdogain group showed the greatest degree of inflammatory reaction and bone resorption. 3. Super EBA group showed moderate inflammation and newly bone formation under the perforation area. 4. MTA group showed minor inflammation, new bone regeneration toward restorative materials and partially cementum growth onto the surface of the material. This group demonstrated a favorable prognosis.

• Restorative Dentistry and Endodontics
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• 제23권1호
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• pp.366-378
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• 1998

Thermocondensation root canal filling technique have been used to fill accessary canals or to obtain homogeneous root caral fillings. But these thermocondensation technique inevitably produce heat in the canal which can be transmitted through the dentin and cementum and consequently damage periodontal ligamental cells and osteoblasts. In this study, System $B^{TM}$(Analytic technology, WA.D.S.A.) was used to evaluate the reaction of periodontal ligament tissue to "Continous Wave condensation technique" introduced by Buchanan, and the transmitted root surface temperature was measured according to measured root thicknesses. 12 Mandibular incisors of two adult dogs were used for the experiment. 6 controls were filled by lateral condensation technique with sealer.3 specimens were apically filled by Continuous Wave technique at $200^{\circ}C$ for 5 seconds and remaining 3 specimens were additionally backfilled using System $B^{TM}$(Analytic technology, WA.D.S.A.) was used to evaluate the reaction of periodontal ligament tissue to "Continous Wave condensation technique" introduced by Buchanan, and the transmitted root surface temperature was measured according to measured root thicknesses. 12 Mandibular incisors of two adult dogs were used for the experiment. 6 controls were filled by lateral condensation technique with sealer.3 specimens were apically filled by Continuous Wave technique at $200^{\circ}C$ for 5 seconds and remaining 3 specimens were additionally backfilled using System $B^{TM}$ at $100^{\circ}C$ for 20 seconds. Six weeks later, the dogs were sacrificed and the teeth stained with Hematoxylin and Eosin for histologic examination. 6 extracted human teeth were used to measure the transmitted temperature. After cutting off the crown, the canals were prepared and divided into 3 groups with root thickness of 1.5mm, 1.0mm, 0.5mm, 2 teeth in each group. Inside each root canal, System $B^{TM}$ was heated as with the temperature for the apically condensed and the back filled group, and the transmitted heat was measured on the external surface of the root. The temperature of System $B^{TM}$ heat spreader at $200^{\circ}C$ and $100^{\circ}C$ was also measured at root temperature. It can be concluded as follows: 1. In the thin area (200-$250{\mu}m$) of the root, root resorption could be seen even with heating at $200^{\circ}C$ for 5 seconds. 2. When the spreader was heated at $200^{\circ}C$ for 5 seconds and additionally at $100^{\circ}C$ for 20 seconds for backfill, all teeth showed root resorption regardless of their root thickness. 3. The transmitted external root surface temperature was higher as the root thickness decreased and as the heating time increased. In the thermocompaction technique using System $B^{TM}$, the spreader should be heated for the minimal time and used only in the apical area. The heated spreader shouldn't inserted to the binding point of the canal and backfilling should be done with other means of minimally heated gutta percha technique.

• 대한치과교정학회지
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• 제29권5호
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• pp.535-549
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• 1999

본 연구는 Contraction Utility Arch wire를 이용하여 성견의 상악 4절치에 후방 견인력과 압하력을 2주와 4주간 적용하여 치아 및 치주 조직의 조직학적 변화를 관찰하여 생체에서 나타나는 생물학적인 효과와 작용의 진행과정을 확인하고자 시행되었다. 생후 약 10개월 정도의 성견 3 마리를 각각 실험군 2마리와 대조군 1 마리로 나누어 제 1, 2 절치에 1mm의 후방 견인력과 60gm의 압하력이 가해지도록 Contraction UTA를 삽입하였다. 장치 부착없이 2주후 희생시킨 것을 대조군으로, 장치 장착 2주후 희생시킨 것을 실험 1군으로, 장치 장착후 재활성화없이 4주후 희생시킨 것을 실험 2군으로 하여 각 군의 제 1, 2 절치에 대한 탈회 표본을 제작하여 Hematoxylin-Eosin염색과 Masson's Trichrome염색을 시행한 후, 각 치아의 치경부 l/3, 치근 중앙 1/3, 치근단 1/3의 치근 및 치아 주위 조직을 광학 현미경 하에서 관찰하여 다음의 결론을 얻었다. 1. 대조군 소견에서, 치주 인대는 치근단 부위에서 치조정까지 일정한 형태를 이루며 비교적 균일한 두께와 연속성을 나타내고 있었으며, 치조골 표면은 조골 세포와 함께 부드러운 골면을 이루고 있었다. 치근의 중앙부 및 치근단 부위에서는 세포성 백악질의 침착을 보였다. 2. 실험 1군의 제 1 절치에서, 치주 인대는 순설측 치경부에서 치근단 방향으로 신장되었다가 치근단부에서 압축되어 치조골에 평행하게 배열되는 소견을 보였으며, 치조골 흡수는 순측 치근 중앙부와 치근단부에서 활발히 진행되고 있었고 순측 치근단 부위의 치아면을 따라 백악질 흡수 부위가 산재되어 나타났다. 제 2 절치 역시 제 1 절치와 유사한 소견을 나타내고 있었으며 설측 치근단부에서 백악질 흡수 소와가 다수 관찰되었다. 3. 실험 2군의 제 1 절치에서,치주 인대의 주행 방향과 간격이 대조군 수준으로 회복되었으나, 치근단부에서는 여전히 혼재된 치주 인대 섬유의 주행이 관찰되었다. 설측 치근 중앙부에서 신생골의 석회화 반응이 강하게 관찰되었고, 순측 치근단부에서 골 흡수와 신생골 석회화가 진행중인 골 부위가 동시에 관찰되었다.

• Journal of Periodontal and Implant Science
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• 제30권3호
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• pp.505-527
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• 2000

The 3 beagle dogs aged over one and half years and weighed 14 to 16 Kg were utilized in this study. Horizontal furcation defects were induced around 3rd, and 4th premolars bilaterally. BMP-4 in conjunction with EGF and BMP-4 only were applied in the right and left premolars respectively. 1 animal was sacrificed at 2nd week, 4th week, and 8th week, after regenerative surgery respectively. Semi-thin sections using glass-knife were stained with hematoxylin- eosin and trichrome for light microscopic study. The results were as follows : 1 . The long junctional epithelial downgrowth was observed in both area applied with BMP-4 and with BMP-4 and EGF at 2nd week after the surgery. 2 . The extensive regeneration of new bone and cementum was appeared at 4th week and the maturation of bone was observed at 8th week in both area applied with BMP-4 and with BMP-4 and EGF. 3 . The root ankylosis and resorption was presented along the exposed root surface at the coronal 1/3 of defect in the BMP-4 applied site, but it was not shown in the site applied with BMP-4 in conjunction with EGF at the 4th week. At 8th week, the root ankylosis was apparently appeared in the BMP-4 and EGF applied site as well as in the BMP-4 applied site. 4 . The periodontal ligament tissue including Sharpey's fiber inserted into cementum and alveolar bone, was formed along the exposed root surface in the area applied with BMP-4 only, but in the site applied with BMP-4 and EGF, the collagen fiber running parallel to the root surface without Sharpey's fiber, was observed in the periodontal ligament space at 4th and 8th week. Within the above results, BMP-4 had the remarkable capability to regenerate the periodontal tissue and EGF had possibility to prevent from the root ankylosis. Therefore, growth factors including BMP-4 and EGF may have the strong possibility to be utilized in the clinical periodontal treatments.