• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제37권3호
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• pp.176-183
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• 2011

Introduction: Very high aggressiveness and recurrence are important clinical characteristics of ameloblastoma compared to the other benign tumors. Therefore, an accurate diagnosis and treatment plan is important. This study examined the association of the clinical findings and recurrence based on the radiological findings of ameloblastoma. In recurrent cases, these results are expected to help in the diagnosis and treatment of ameloblastoma to examine the relevance with the clinical characteristics and radiological features. Materials and Methods: For a clinical (gender, age) and radiological (location, internal pattern, size, perforation, border pattern, impacted tooth, root resorption) evaluation, this study examined 156 cases of 147 patients diagnosed with ameloblastoma, who had been treated and in most cases regularly checked at the department of oral and maxillofacial surgery, Kyungpook National University Hospital, between January 1993 and December 2009. For a recurrent rate evaluation, a more than 3 years follow-up period is needed. Accordingly, 116 patients diagnosed with ameloblastoma between January 1994 and December 2007 were investigated. Results: The recurrence rate in all cases was 6.1% but was 7.8% in cases with follow-up periods more than 3 years. The male-to-female ratio was 3:2, showing a slight male predilection. Ameloblastoma had a peak occurrence in the second decade of life followed by the fourth decade of life. The mandibular angle area is the most frequent site of ameloblastoma (50.8%) in the jaws. Six cases of unilocular (7.8%) and 3 cases of multilocular (7.7%) ameloblastomas recurred. Seven cases of smooth (10%) and 2 cases of irregular (4.3%) ameloblastomas recurred. No cases of ameloblastomas without perforation of the cortical bone (0%) and 9 cases with a perforation of cortical bone (11.1%) recurred. Four cases of the ameloblastomas with impacted teeth (11.4%) and 5 cases of ameloblastomas without impacted tooth (6.2%) recurred. Seven cases of ameloblastomas with root resorption (10.9%) and 2 cases of ameloblastomas without root resorption (3.8%) recurred. Conclusion: A multiple smooth margin, unilocular ameloblastoma with an impacted tooth, root resorption tends to recur more easily. Therefore, they need to be treated more carefully and require a a longer follow-up.

• 대한치과보철학회지
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• 제33권3호
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• pp.517-538
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• 1995

Dental implantation is a method restoring missing teeth, especially in the case of severely resorbed edentulous patient. But the direct contact between bone and implant surface, induces stress concentration to the bone and eventually becomes a cause. The purpose of this study was to compare the stress distribution patterns between following two cylindrical implant models. One group has implant apex located in the inferior cortical bone and the other in the cancellous bone. Anterior edentulous mandible was modeled with two dimensional 953,878 nodes, 995,918 elements and compared the deflection and stress distribution under the 70 N,4 load cases for 26 models having variant mandibular height and length. The result were as follows; 1. The stress concentration was more affected by the height of the mandible than implant length. 2. Bicortication mitigates the stress of upper cortical and cancellous bone area at the same height of the mandible 3. Perforation of the inferior mandibular cortex significant stress concentration. 4. Stud type porstheses induced less stress concentration to the cortical and cancellous bone than bar type prostheses. 5. Stress of implant apex for stud type was larger than that of bar type.

• Imaging Science in Dentistry
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• 제45권2호
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• pp.109-115
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• 2015

Central odontogenic fibroma (COF) is a rare benign tumor that accounts for 0.1% of all odontogenic tumors. A case of COF (simple type) of the mandible in a four-year-old boy is described in this report. The patient showed asymptomatic swelling in the right inferior border of the lower jaw for one week. A panoramic radiograph showed a poorly-defined destructive unilocular radiolucent area. Cone-beam computed tomography showed expansion and perforation of the adjacent cortical bone plates. A periosteal reaction with the Codman triangle pattern was clearly visible in the buccal cortex. Since the tumor had destroyed a considerable amount of bone, surgical resection was performed. No recurrence was noted.

• 대한치과의사협회지
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• 제22권11호통권186호
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• pp.973-978
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• 1984

The authors observed a case of Burkitt's lymphoma, occurred in the mandible, of 6-year-old female patient who admitted to the Department of Oral Radiology, Kyung Hee University Medical Center. The serial radiograms, clinical findings, and microscopid findings had been taken and obtained following results: 1. In serial radiograms, invasive and infiltrative bone destruction in the both mandibular body region was observed. Perforation and erosion of cortical plate of the mandibular angle area and loss of alveolar lamina dura in involved teeth were also noticed. 2. In microscopic findings, a monotous overgrowth of undifferentiated monomorphic lymphoreticular cells found. Macrophages with and abundant clear cytoplasm are usually found scattered uniformly throughout the tumor, producing the very characteristic 'starry-sky' appearance.

• Imaging Science in Dentistry
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• 제39권1호
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• pp.51-54
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• 2009

Although odontogenic myxoma (OM) has various radiographic appearances, the characteristic features of OM are the multilocular radiolucent lesion, straight bony septa along the margin forming either square or triangular spaces. We present a case of OM in a 25-year old-male patient. Multilocular radiolucent lesion on the left mandible body showed tennis racket appearance. Cone beam computed tomography (CBCT) showed straight bony septa along the margin and cortical perforation. This CBCT features would have significantly contributed to allowing a diagnosis of OM. We think that this case shows characteristic radiographic features of odontogenic myxoma.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제46권5호
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• pp.358-360
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• 2020

The management of odontogenic keratocysts (OKC) remains a hotly debated topic in oral and maxillofacial surgery. Despite numerous studies and systematic reviews on treatment options, there is a lack of consensus and no accepted protocol on the management of OKC. Hence, the aim of this study was to briefly summarize all large systematic reviews in the literature on the management of OKC and formulate an evidence-based management protocol. Data from five large systematic reviews were combined to calculate the mean recurrence rate for each technique. Decompression followed by enucleation along with adjuvant methods such as application of Carnoy's solution and peripheral ostectomy can result in very low recurrence and is an acceptable first line treatment. The surgical approach should be determined by lesion size, patient age, proximity to vital structures, accessibility, soft tissue/cortical perforation, and if the lesion is recurrent.

• Imaging Science in Dentistry
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• 제40권3호
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• pp.149-153
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• 2010

Brown tumor is usually diagnosed at the terminal stage of hyperparathyroidism. Diagnosis of this tumor is confirmed by endocrinologic investigations along with clinical and radiographic examination. Radiographical differential diagnosis of this tumor includes central giant cell granuloma, aneurysmal bone cyst, metastatic tumor, multiple myeloma, and Paget disease. This report presents a rare case of multiple brown tumors occurring at the maxilla and mandible, which was initially misdiagnosed as central giant cell granuloma. Plain radiographs demonstrated multiple well-defined multilocular radiolucency. CT images showed soft tissue mass with low attenuated lesions, perforation of the lingual cortical plate, and a heterogeneous mass at the right thyroid lobe. These findings were consistent with parathyroid adenoma. The patient had hypercalcemia, hypophosphatemia, and elevated alkaline phosphatase level. Surgical excision of the tumor was performed. No recurrence was observed during a 28-month follow-up.

• Imaging Science in Dentistry
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• 제50권4호
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• pp.359-363
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• 2020

Ameloblastic carcinoma is a rare odontogenic malignant tumor with the histologic features of both ameloblastoma and carcinoma. It occurs more frequently in the mandible than in the maxilla and it may appear de novo or develop from a preexisting ameloblastoma or odontogenic cyst. Rapidly progressing, painful swelling is the most common symptom, and radiographically, it shows significant bone resorption and cortical perforation. This report described a case of ameloblastic carcinoma in a 45-year-old man who presented with swelling in the left mandible. The lesion showed combined features of benign findings, such as an expansile cortex with a distinct border, and malignant findings, such as a large exophytic mass with frank bone resorption. Excisional biopsy was performed and a final diagnosis of ameloblastic carcinoma was made.

• Journal of Audiology & Otology
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• 제25권4호
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• pp.224-229
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• 2021

Background and Objectives: The United Kingdom (UK) national standard for the closure rate for myringoplasty is 89.5% (90.6% and 84.2% for primary and revision surgeries, respectively). The average hearing gains for primary and revision myringoplasty are 9.14 dB and 7.86 dB, respectively. This study compared the myringoplasty outcomes for a single surgeon over 5 years. Subjects and Methods: Data for 68 cases were analyzed retrospectively. The outcome measures were achievement of the tympanic membrane closure and the average hearing gain or loss. Results: The overall and primary closure rates were 97% and 98%, respectively and significantly higher than the UK national standard (p=0.0210 and p=0.0287, respectively). The revision closure rate was 93%; however, it was not significantly higher than the national standard (p=0.1872). The average hearing gain was 5.18 dB. The gains for primary and revision surgeries were 5.15 dB and 5.25 dB, respectively. Conclusions: We propose that these outcomes are a result of our surgical technique, including the simultaneous use of cortical mastoidectomy in ears with discharge.

• 대한청각학회지
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• 제25권4호
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• pp.224-229
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• 2021

Background and Objectives: The United Kingdom (UK) national standard for the closure rate for myringoplasty is 89.5% (90.6% and 84.2% for primary and revision surgeries, respectively). The average hearing gains for primary and revision myringoplasty are 9.14 dB and 7.86 dB, respectively. This study compared the myringoplasty outcomes for a single surgeon over 5 years. Subjects and Methods: Data for 68 cases were analyzed retrospectively. The outcome measures were achievement of the tympanic membrane closure and the average hearing gain or loss. Results: The overall and primary closure rates were 97% and 98%, respectively and significantly higher than the UK national standard (p=0.0210 and p=0.0287, respectively). The revision closure rate was 93%; however, it was not significantly higher than the national standard (p=0.1872). The average hearing gain was 5.18 dB. The gains for primary and revision surgeries were 5.15 dB and 5.25 dB, respectively. Conclusions: We propose that these outcomes are a result of our surgical technique, including the simultaneous use of cortical mastoidectomy in ears with discharge.