• Maxillofacial Plastic and Reconstructive Surgery
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• 제28권1호
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• pp.58-67
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• 2006

In the recent studies, many authors have reported that the success rate of immediate implantation has no difference compared to conventional staged implantation. Although the immediate implantation has many advantages over conventional approach, many clinicians don't seem to practice because they think that most of the extraction sockets will have some bony gab with defects around implant and that this situation makes the result of immediate implantation unpredictable. We clinically analyzed 23 implanted sites of 18 patients treated with immediate implantation in our hospital from September 2003 to January 2004. The $ITI^{(R)}$. dental implant system was used and GBR procedure with $Bio-Oss^{(R)}$. and $Bio-Gide^{(R)}$. was done simultaneously. The pre & post-op. measurements were recorded such as alveolar crest-adjacent tooth CEJ distance, gingival crest-adjacent tooth CEJ distance, existence of periapical lesion, vertical defect around the extraction socket, horizontal defect around the extraction socket, probing depth, radiologic change of alveolar crest height. We report a positive outcome about immediate implantation with review of literatures.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1587-1590
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• 2005

A rigid-plastic finite element analysis for the die forging process of a socket ball joint, which is used in the transportation system, was carried out. And also with the results, the elastic stress analysis for the forging die was performed in order to get basic data for the die life prediction. The die fatigue life prediction was simulated using Goodman's and Gerber's equation. The prediction technique for the fatigue life of a forged product, the socket ball joint, using DEFORM-3D is presented and the results are commented upon. Archard's wear model was used for the wear simulation and then the wear simulation and then the wear quantity was quantity was evaluated using volume. In order to prove the wear simulation results to be reliable, wear quantity of the real forging die set in used a forging factory was measured using a 3-dimensional measurement apparatus. The simulation results were relatively in good agreement with the experimental measurements.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제23권2호
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• pp.155-162
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• 2001

This is a clinical study on patients who had visitied the Emergency Room of Pusan National University Hospital and then been treated in the Department of Oral and Maxillofacial Surgery during recent 5 years, from 1992 to 1996. The results were as follow ; 1. The total number of patients was 2,680 and the ratio of male to female was 1.96:1, The highest monthly incidence was shown in September(12.1%) and October(10.5%) and the age distribution peaks was the third decade(24.3%), followed by the first(23.1%) and the fourth decade(17.2%). 2. Soft tissue injury group(29.1%) was the most prevalent, followed by tooth injury group(16.1%), facial bone injury group (16.0%), toothache group(11.2%), socket bleeding group(11.1%), infection group(9.8%) and TMJ dislocation group(5.9%). 3. The percentage of in-patients and out-patient were 21.6% and 78.4%, respectively. The frequent causes of admission were facial bone fracture(73.8%), infection(20.8%) and soft tissue injury(4.8%) in order. However, soft tissue injury was the most frequent cause in out-patient, followed by tooth injury(20.5%), toothache(14.3%), socket bleeding(14.2%) and TMJ dislocation(7.6%). 4. In the facial bone injury group, the mandibular fractures(70.6%) showed the highest incidence, followed by zygomatic bone and arch fractures(7.5%), maxillary bone fractures(4.0%) and nasal bone fractures(4.0%). 5. In the mandibular bone fracture, the most common location was symphysis(36.7%), followed by the mandibular angles(33.1%) and the condyles(21.8%). 6. The common causes of facial bone fractures were violence, fall and traffic accident in order. 7. The common causes of soft tissue injury were fall down, fight and traffic accident in order and the highest incidence was observed in infants before the age of 10 years(44.0%). 8. In the group of tooth injury, tooth luxation(38.5%) showed the highest incidence followed by tooth fracture(33.2%) and tooth loss(17.1%). The common causes of tooth injury were fall, fight and traffic accident in order. 9. In infected patients group, the ratio of in-patients to out-patients was 1 : 1.28, Buccal(24,7%) and infraorbital space abscess(23.3%) showed the highest incidence. 10. The pain caused by dental caries(39.0%) and pericoronitis(26.6%) showed high incidence in the toothache group. 11. The high incidence was observed during third(34.0%) and fourth (24.5%) decades in TMJ dislocation group. 12. In the group of socket bleeding patients, 92% was post-operative hemorrhage and 8% was accompanied with other systemic hemorrhagic diseases.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제41권
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• pp.32.1-32.7
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• 2019

Background: Tooth extraction commonly leads to loss of residual alveolar ridge, thus compromising the room available for the implant placement. To combat the post-extraction alveolar loss, alveolar ridge preservation is practiced, with the advent of the biomaterial available. The purpose of this study was to assess the efficiency of calcium phosphosilicate biomaterial in alveolar ridge preservation. Twenty patients indicated for extraction were selected followed by socket grafting using calcium phosphosilicate. Implant placement was done 6 months postoperatively during which a core was harvested from the preserved sockets. Clinico-radiographic measurements of hard and soft tissues were taken at baseline and 6 months post-grafting. Results: There were no significant changes in the radiographic and soft tissue parameters while significant changes in hard tissue parameters with 1.9 mm (p = 0.013) gain in mid-buccal aspect and 1.1 mm (p = 0.019) loss in horizontal bone width were observed. The histomorphometric evaluation depicted the vital bone volume of 54.5 ± 16.76%, non-mineralized tissue 43.50 ± 15.80%, and residual material 2.00 ± 3.37%. Conclusion: The implants placed in these preserved ridges presented 100% success rate with acceptable stability after a 1-year follow-up, concluding calcium phosphosilicate is a predictable biomaterial in alveolar ridge preservation.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제34권4호
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• pp.280-285
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• 2012

From the standpoint of general guidelines of a dentist, the following conditions should be considered before replanting a permanent tooth. The avulsed tooth should be without advanced periodontal disease. The alveolar socket should be reasonably intact in order to provide a seat for the avulsed tooth. The extra-alveolar period should be considered, i.e. periods exceeding. 2 hours are usually associated with marked root resorption. But, the above mentioned regulations are often difficult to keep in the actual situation of the medical emergency room, owing it to the delay of primary medical care in multiple trauma patients. The successful cases have been reported with minimal root resorption in the long-term periods, in spite of extra-alveolar periods of several hours and combined alveolar bone fracture. This is a case report regarding the effect of endodontic drainage in delayed replantation after a prolonged extra-alveolar period of the avulsed teeth with alveolar bone fracture.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제39권
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• pp.18.1-18.4
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• 2017

Background: Postoperative infection occurs when bone graft material is dislodged into the maxillary sinus cavity and most of the patients are often uncomfortable with the drainage and irrigation procedures to eradicate the infection. In this case report, we share a technique in treating patients with such condition. Material and methods: A 47-year-old patient was referred after sinus elevation using the crestal socket osteotome, bone graft, and implant insertion at a local clinic. Clinical and radiographic findings confirmed the diagnosis of right maxillary sinusitis. A surgical and medical treatment regimen was applied. Results: By using this technique for irrigation, we were able to achieve successful results, and the patient was satisfied due to less discomfort during the irrigation process. Conclusion: This method is a patient-friendly technique for sinus irrigation. It is not only limited to sinus grafted patients, but also maxillary sinusitis patients in any other type of odontogenic infection.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권5호
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• pp.389-395
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• 2010

Purpose: Although it is generally accepted that patients with controlled diabetes have similar rates of success for dental implants as healthy individuals, the use of dental implants in diabetic patients is controversial. In addition, the impact of diabetes on the healing of bone associated with immediately place dental implants is not completely understood. The purpose of this study was to measure bone response to implants radiologically in uncontrolled and insulin-controlled diabetic rats. Materials and Methods: Twenty rats were divided into control, insulin-treated and diabetic groups. The rats received streptozotocin (60 mg/kg) to induce diabetes; animals in the insulin-treated group also received three units of subcutaneous slow-release insulin. Two titanium implants ($1.2{\times}3$ mm) were placed in the extraction socket of the maxillary first molars of the animals and were harvested at 3 days, 1, 2 and 4 weeks. The bone density was measured by digital radiography using gray-level analysis (histogram) in the regions of interest (ROI) at four points: two mesial and two distal to both sides of the implant. Results: The results showed that the osseointegration of the implants was impaired in the diabetic rats compared to the control and the insulin-treated rats. The radiographic evidence demonstrated marked destruction of bone around the implants in the diabetic group. Both the control and the insulin-treated groups had a significantly higher bone density on radiograph than the diabetic group from the 1 week of the experiment (P<0.05 for each comparison). Conclusion: The present study revealed that the immediate placement of titanium implants in the maxilla of diabetic rat lead to delay in the maturation of bone adjacent to implants. It is expected that the reduced predictability of success of immediate implantation in patient with the uncontrolled diabetes.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제23권3호
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• pp.217-225
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• 2001

Any fracture passing through the socket of a teeth is compounded intraorally, even if the fracture is not displaced and the tooth is firm in its socket. Before the advent of antibiotic therapy the danger of infection in a compounded fracture posed severe problems in treatment. Infection is reduced by antibiotic therapy but prolonged use of antibiotics is not justified in an attempt to save a tooth which might eventually be sacrificed. There is still controversy in the management of third molar in mandibualr angle fracture, particulary in regard to their retention or removal at the time of fracture treatment. So we surveyed the 159 patients who were treated with open reduction of mandibular angle fracture containing third molar in fracture line, and compared with the postoperative infection rate depending on time intervals between injury and operation, eruption state of third molar, non-extraction or extraction of third molar related to eruption state, non-extraction or extraction of third molar related to condiition of third molar and its surrounding periodontium and were to propose treatment guidline of third molar in mandibular angle fracture The results obtained were as follows : 1. There were no statistical significance between the time from injury to operation and postoperative infection. 2. There were no statistical significance between eruption state of third molar and postoperative infection. 3. In case of retention of the third molar, there were no statistical significance between eruption state of third molar and postoperative infection, but in case of extraction, postoperative infection was high rate in complete impacted cases. 4. There were no statistical significance between non-extraction or extraction of third molar and postoperative infection depending on condition of third molar. There are no difference in infection rate statistically according to the time from injury to operation, eruption state and condition of third molar, but retention of third molar revealed lowered infection rate in completely impacted cases. By terms of the manegement of third molar, we should extract or preserve third molar in the line of the mandibular angle fracture according to possibility of infection.

• 대한토목학회논문집
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• 제26권6C호
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• pp.395-406
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• 2006

상부의 큰 하중을 지탱해야 하는 경우에는 일반적인 기초 형식으로서 현장타설말뚝공법이 많이 사용된다. 이러한 현장타설말뚝의 시공은 연약한 토사 지반을 관통하여 암반까지 굴착을 실시하는 것이 일반적이며, 지지력의 대부분은 암반층 근입부에서 발휘되게 된다. 현장타설말뚝의 지지력은 선단지지력과 주면저항력의 조합으로 이루어지게 되며, 과도한 침하가 발생하지 않고 지지력을 얻기 위해서는 근입부의 직경과 길이가 충분하여야 한다. 말뚝의 극한지지력에 있어서 선단지지력은 큰 비중을 차지한다. 그러나, 일반적으로 주면저항력은 선단지지력에 비해서 훨씬 작은 두부 침하량에서 발현된다. 또한 선단부 거동특성은 천공과정에서 발생하는 근입부 바닥에서의 잔류물에 의해서 영향을 받게 된다. 그러나 이러한 잔류물을 근입부에 잔류시키지 않기 위해서는 시공과 검사가 제대로 이루어져야 한다. 이것은 매우 어려우며 비경제적이다. 특히 암반층 근입부가 깊은 경우에는 물이나 천공 슬러리를 사용하여야 하므로 더욱 어렵다. 이러한 이유들로 인해서 작용 하중하에서 말뚝의 거동은 주면부 거동특성에 따라 좌우되게 된다. 따라서 복잡한 발현기구를 가진 주면저항력에 대해서 주로 관심을 가지게 되는 것이다. 본 연구에서는 주면저항력에 관해서만 연구를 하였다. 콘크리트 말뚝체와 주변 암반 사이의 상호작용은 말뚝 거동특성에 있어서 가장 중요한 요소이며, 시공방법에 따라서 큰 영향을 받는다. 본 연구에서는, 탄소성 해석(FLAC 2D)을 통하여 근입부의 거칠기 경사, 높이와 같은 거칠기 특성, 근입부를 형성하는 주변 암반의 강도 특성과 변형 특성, 근입부의 깊이와 길이 등이 최대단위주면저항력에 미치는 영향에 대한 검토를 실시하였다. 변수 연구를 통하여 최대단위주면저항력에 있어서는 근입부의 연직응력, 거칠기 높이와 근입부 암반의 점착력 및 포아슨비가 중요한 요소임을 확인하였다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제30권5호
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• pp.465-472
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• 2008

We experienced a rare case of oral squamous cell carcinoma arisen from gingival tissues overlying prolonged chronic osteomyelitis of the mandible. A 66 years old man complained of unhealed extraction sockets of left mandibular second premolar and first molar, and showed extensive leukoplakia in the gingival tissues of the same area. The inflammation of the socket granuloma became severe and extended into adjacent mandibular proper, resulted in diffuse suppurative chronic osteomyelitis of mandibular body, exhibiting irregular osteolytic changes of mandibular trabecular patterns in mottled radiolucent appearance. The leukoplakia was initially diagnosed under microscope, and the involved gingival tissues were radically removed. Thereafter, the gingival soft tissue inflammation involving the mandibular osteomyelitis was hardly healed for two years. During the period of repeated surgical treatments for the inflamed lesion, nine biopsies were taken sequentially. Until the eighth biopsy, there consistently showed the suppurative osteomyelitis with ingrowing gingival tissues into the bony inflammatory lesion. The gingival epithelium showed the features of leukoplakia but no evidence of malignant changes. However, the ninth biopsy, taken about 2 years after initial diagnosis, showed the early carcinomatous changes of the gingival epithelium. The neoplastic epithelial cells were relatively well differentiated with many keratin pearls, and infiltrated only into underlying connective tissues. So, we presumed that the present case of squamous cell carcinoma was caused by the persistent inflammatory condition of the mandibular osteomyelitis, and also suggest that the leukoplakia should be carefully removed in the beginning to prevent the neoplatic promotion of the chronic inflammation.