• 대한한의학회지
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• 제19권1호
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• pp.5-18
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• 1998

The purpose of this study was to determine the effects of aqua-acupuncture of Laennec N HO (Hominis placenta Cervi pontotrichum cornu Carthami semen). on trabecular area and physiological change in ovariectomized osteoporotic rats. This experiment was performed to .investigate an antiosteoporosis. effects of Laennec N HO(Hominis placenta Cervi pontotrichum cornu Carthmi semen) aqua-acupuncture on the osteoporosis induced by both ovariectomy in Rats. So rats were divided into Sham group and OVX group. OVX groups were divided into control group, Exp. I group, Exp II group and Exp III group). The Ratios of trabecular area seen in ephiphysis and diaphysis of tibia and lumbar vertebral body and physiological change were as follows. 1. In the proximal ephiphysis of tibia, Exp I II III groups were significantly increased compared to that in control group (p<0.05). 2. In the diaphysis of tibia, Exp III group were significantly increased compared to that in control group (p<0.05). 3. In the first lumbar vertebral body, Exp II group were significantly increased compared to that in control group. 4. In the cortical thickness index of tibia, Exp III III groups were significantly increased compared to that in control group. 5. Osteoca1cin was increased in the Exp II group than those of other Experiment groups and control group, and Phosphorus was decreased in the Exp I II group than that in control group, But a significant difference was not seen. GOT, GPT and Alkaline phosphatase were decreased in all Experiment groups than that in control group. But a significant difference was not seen. From the above results, it might be suggested that aqua-acupuncture Laennec N HO(Hominis placenta Cervi pontotrichum cornu Carthami semen) prevented the increase in bone turnover and the decrese in bone mass induced by OVX in rats.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제41권1호
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• pp.3-10
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• 2015

Objectives: We retrospectively evaluated the impact of mandibular third molars on the occurrence of angle and condyle fractures. Materials and Methods: This was a retrospective investigation using patient records and radiographs. The sample set consisted of 440 patients with mandibular fractures. Eruption space, depth and angulation of the third molar were measured. Results: Of the 144 angle fracture patients, 130 patients had third molars and 14 patients did not. The ratio of angle fractures when a third molar was present (1.26 : 1) was greater than when no third molar was present (0.19 : 1; odds ratio, 6.58; P<0.001). Of the 141 condyle fractures patients, the third molar was present in 84 patients and absent in 57 patients. The ratio of condyle fractures when a third molar was present (0.56 : 1) was lower than when no third molar was present (1.90 : 1; odds ratio, 0.30; P<0.001). Conclusion: The increased ratio of angle fractures with third molars and the ratio of condyle fractures without a third molar were statistically significant. The occurrence of angle and condyle fractures was more affected by the continuity of the cortical bone at the angle than by the depth of a third molar. These results demonstrate that a third molar can be a determining factor in angle and condyle fractures.

• Journal of Korean Dental Science
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• 제10권2호
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• pp.66-73
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• 2017

Purpose: To evaluate the effect of different-sized drill tips and laser irradiation times on the initial stability of orthodontic miniscrews placed in Er,Cr:YSGG-laser pre-drilled holes in an animal model. Materials and Methods: Laser pre-drilled holes were made in dog mandibular bone with an Er,Cr:YSGG laser using irradiation times of 5, 7, 9, 11, and 13 seconds, and tip diameters of 0.4 and 0.6 mm. The maximum diameter and depth of the pre-drilled holes was measured with micro computed tomography. The maximum insertion torque was measured during placement the miniscrew. Result: Laser pre-drilled holes were conical shaped. The maximum diameter of pre-drilled holes increased with longer laser irradiation times (P>0.05) and larger tip diameters (P<0.05). The depth of pre-drilled holes increased with longer laser irradiation times and larger tip diameters (P<0.05). When the 0.4 mm tip, but not the 0.6 mm tip, was used, the insertion torque decreased significantly with longer laser irradiation times (P<0.05). Conclusion: Tip diameter impacted insertion torque more than irradiation time. It takes at least 9 seconds using a 0.6 mm tip to create a 0.8 mm diameter and 1.0 mm depth hole in thick cortical bone.

• 대한골관절종양학회지
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• 제8권2호
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• pp.58-62
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• 2002

골의 거대세포종은 원발성 골 종양의 5-10%를 차지한다. 주로 20-40세 사이의 연령에서 많으며 90% 이상이 장골에 발생하지만 아주 드물게 수부나 족부 같은 편평골이나 단골에도 발생한다. 주요 증상은 동통이며 종종 병적 골절이나 심지어 연부 조직의 침범이 동반될 수있다. 방사선학적으로 골간단에 음영이 감소된 균질의 골 용해 소견이 보이며 주위에 반응성골 형성은 없다. 치료는 골 종양의 병기에 따라 차이가 있으며 재발율을 줄이고 침범 부위의 기능을 보존할 수 있는 수술적 치료가 필요하다. 비진행성 병기는 소파술후 골이식이나 골시멘트 충전을 할 수 있고 진행성 병기는 광범위 절제술후 관절 고정술이나 종양 대치물로 사지 구제술을 시행한다. 전이, 국소재발을 주기적으로 관찰해야 한다. 저자들은 족부의 외측 설상골에 발생한 거대 세포종을 경험하였기에 보고하고자 한다.

• 대한심미치과학회지
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• 제27권2호
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• pp.97-104
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• 2018

하악 전치부는 다른 구강 내 영역에 비해 높은 임플란트 성공률과 더 나은 접근성을 갖고 있다. 비록 부적절한 드릴링으로 인한 설측 피질골 천공 가능성과 설동맥 손상으로 인한 출혈 가능성이 있더라도 다른 부위와 비교했을 때 주요 해부학적 구조물이 적기 때문에 상대적으로 안전하다. 또한 상악 전치부와 비교했을 때 환자들이 심미적으로 덜 민감한 부위이다. 그러나 좁은 협설측 치조골 폭 때문에 이상적인 임플란트 식립 위치로의 식립은 상악 전치부만큼 어렵다. 이러한 하악 전치부에서 일체형 임플란트는 매우 유용한 치료방법이다. 하악 전치의 해부학적 치근형태와 얇은 치조골을 고려할 때, 임상적으로 3mm보다 큰 직경의 임플란트 식립은 어렵다. 본 증례는 하악 전치부 무치악 부위에서 일체형 임플란트의 식립과 즉시 부하를 동반하여 심미적인 보철물을 구현한 경우이다.

• Imaging Science in Dentistry
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• 제51권1호
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• pp.73-80
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• 2021

Purpose: The purpose of this study was to evaluate the cone-beam computed tomographic (CBCT) imaging and histopathological characteristics of osteoradionecrosis(ORN) and medication-related osteonecrosis of the jaw(MRONJ). Materials and Methods: Ten surgical specimens from segmental mandibulectomy (3 ORN and 7 MRONJ) were analyzed using CBCT. The CBCT parameters were as follows: high-resolution mode (tube voltage, 90.0 kV; tube current, 4.00 mA; rotation time, 16.8 s; field of view, 56 mm×56 mm; thickness, 0.099 mm). Histopathological characteristics were evaluated using histological slides of the surgical specimens. The Pearson chi-square test was used to compare ORN and MRONJ in terms of CBCT findings(internal texture, sequestrum, periosteal reaction and cortical perforation) and histopathological characteristics(necrotic bone, inflammatory cells, reactive bone formation, bacteria, Actinomyces, and osteoclasts). A P value less than 0.05 was considered to indicate statistical significance. Results: MRONJ showed periosteal reaction on CBCT more frequently than ORN (7 of 7 [100%] vs. 0 of 3 [0%], P<0.05). Regarding histopathological characteristics, MRONJ showed osteoclasts more frequently than ORN (6 of 7 [85.7%] vs. 0 of 3 [0%], P<0.05). Conclusion: This study evaluated the CBCT imaging and histopathological characteristics of ORN and MRONJ, and the findings suggest that CBCT could be useful for the evaluation of ORN and MRONJ.

• The Journal of Advanced Prosthodontics
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• 제13권6호
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• pp.396-407
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• 2021

PURPOSE. Zirconia has exceptional biocompatibility and good mechanical properties in clinical situations. However, finite element analysis (FEA) studies on the biomechanical stability of two-piece zirconia implant systems are limited. Therefore, the aim of this study was to compare the biomechanical properties of the two-piece zirconia and titanium implants using FEA. MATERIALS AND METHODS. Two groups of finite element (FE) models, the zirconia (Zircon) and titanium (Titan) models, were generated for the exam. Oblique (175 N) and vertical (175 N) loads were applied to the FE model generated for FEA simulation, and the stress levels and distributions were investigated. RESULTS. In oblique loading, von Mises stress values were the highest in the abutment of the Zircon model. The von Mises stress values of the Titan model for the abutment screw and implant fixture were slightly higher than those of the Zircon model. Minimum principal stress in the cortical bone was higher in the Titan model than Zircon model under oblique and vertical loading. Under both vertical and oblique loads, stress concentrations in the implant components and bone occurred in the same area. Because the material itself has high stiffness and elastic modulus, the Zircon model exhibited a higher von Mises stress value in the abutments than the Titan model, but at a level lower than the fracture strength of the material. CONCLUSION. Owing to the good esthetics and stress controllability of the Zircon model, it can be considered for clinical use.

• 대한두경부종양학회지
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• 제37권1호
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• pp.33-37
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• 2021

Intraosseous hemangioma is a rare, benign vascular tumor of endothelial origin. It accounts for fewer than 1% of all hemangiomas, and very rarely occurs in the face. Intraosseous hemangioma usually presents as an asymptomatic lesion, but symptoms can occur due to the mass effect. The authors describe a case of intraosseous hemangioma of the zygoma with a review of the relevant literature. A 44-year-old man presented with a chief complaint of painless swelling on the left zygomatic region that had been slowly growing for the past year. On physical examination, a hard, non-movable mass in a deep layer was palpated. On computed tomography performed to evaluate its layers and extent, trabeculation was found inside the mass, but the lack of destruction of the surrounding bone suggested that the mass was benign. Complete surgical excision was performed under local anesthesia. After complete excision of the mass, slight erosions remained on the cortical bone of the zygoma, but because it was small enough not to cause a facial deformity such as depression or asymmetry, no additional reconstructive procedure was performed. There were no symptoms or recurrence during a 8-month follow-up period.

• Archives of Plastic Surgery
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• 제50권1호
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• pp.49-53
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• 2023

Juvenile ossifying fibroma (JOF) is a variant of the ossifying fibroma and includes two histopathological subtypes: trabecular and psammomatoid. Psammomatoid JOF (PJOF) in craniofacial structures should be distinguished from other fibro-osseous lesions, such as fibrous dysplasia (FD), considering the difference in the treatment protocols. Here, we present a rare case of PJOF that was initially misdiagnosed as a case of FD and emphasize the importance of considering JOF in the differential diagnosis of patients with craniofacial fibro-osseous lesions. A 4-year-old boy demonstrated progressive enlargement of the zygomaticomaxillary area on his left side for the last 6 months. The patient was diagnosed as a case of FD based on the clinical features and radiographic findings, and was operated considering the rapid progression. To achieve facial symmetry, contouring of the zygomatic bone and arch was performed. However, the patient demonstrated rapid enlargement at the 3-month postoperative follow-up. The decision was made to surgically remove the tumor due to visual field impairment. Intraoperatively, a rubbery mass, which was separated from the surrounding cortical bone, was identified and excised. The lesion was confirmed as PJOF by histopathological examination. The possibility of PJOF should not be ruled out in the differential diagnosis of patients with fibrous-osseous lesions. In the event of suspected PJOF, accurate diagnosis should be made through definitive biopsy.

• Journal of Periodontal and Implant Science
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• 제29권1호
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• pp.209-231
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• 1999

Even though titanium(Ti) and its alloys are the most used dental implant materials, there are some problems that Ti wears easily and interferes normal osteogenesis due to the metal ions. Ti coated with bioactive ceramics such as hydroxyapatite has also such problems as the exfoliation or resorption of the coated layer, Recent studies on implant materials have been proceeding to improve physical properties of the implant substrate and biocompatibility of the implant surfaces. The purpose of the present study was to examine the physical property and bone tissue compatibility of bioinert nitrides ion plated Ti, Button type specimens(14mm in diameter, 2.32rrun in height) for the abrasion test and cytotoxicity test and thread type implants(3.75mm in diameter, 6mm in length) for the animal experiments were made from Ti(grade 2) and 316LVM stainless steel. Ti specimens were ion plated with TiN, ZrN by the low temperature arc vapor deposition, and the depth profile of the TiN/Ti, ZrN/Ti ion plated surface was examined by Auger Electron Spectroscopy. Three kind of button type specimens .of TiN/Ti, ZrN/Ti and Ti were used for abrasion test, and HEPAlClC7 cells and CCD cells were cultivated for 4 days with the specimens for cytotoxicity test. Thread type implants of TiN/Ti, ZrN/Ti, Ti, 316LVM were implanted on the femur of 6 adult dogs weighing 10kg-13kg. Two dogs were sacrified for histological examination after 45 days and 90 days, and four dogs were sacrified for the removal torque test of the implant') after 90 days. The removal torque force was measured by Autograph (Shimadzu Co., AGS-1000D series, Japan). Abrasion resistance of TiN/Ti was the highest, and that of ZrN/Ti and Ti were followed. The bioinert nitride ion plated Ti had much better abrasion resistance, compared with Ti, In the cytotoxicity test, the number of both cells were increased in all specimens, and there were no significant difference in cytotoxic reaction among all groups (p>0.1), In histological examination, 316LVM showed the soft tissue engagement in interface between the implant and bone, but the other materials after 45 days noted immature new bone formation in the medullary portion along the implant surface, and those after 90 days showed implant support by new bone formation in both the cortical and the medullary portion, The removal torque force of Tilv/Ti showed significantly higher than that of Ti(p(O,05). The difference in removal torque force between TiN/Ti and ZrN/Ti was not significant(p>0.05), and that of 316LVM was lowest among all groups(p<0.05). These results suggest that bioinert nitrides ion plated Ti can resolve the existing problems of Ti and bioactive ceramics, and it may be clinically applicable to human.