• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.23 no.2
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• pp.255-264
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• 1993

The purpose of this study was to obtain some informations for the radiographic differential diagnosis between dentigerous cysts and unicystic ameloblastomas in the mandible. The authors observed and compared the clinico-radiographic features of 38 cases of dentigerous cyst and 32 cases of unicystic ameloblastoma associated with impacted mandibular molar. The obtained results were as follows: Dentigerous cysts occurred the most frequently in the 3rd decade, but unicystic ameloblastomas in the 2nd decade, and both lesions occurred with slight predilection in males. Average of lesional size of unicystic ameloblastomas was larger than that of dentigerous cysts, and lesions of over 25㎠ were only in unicystic ameloblastomas. Cortical thinning and expansion were more frequently observed in unicystic ameloblastomas at 72.9% than in dentigerous cysts at 15.8%. Dentigerous cysts showed smooth border at 89.5%, but unicystic ameloblastomas showed smooth border at 53.1% and scalloped border at 46.9%. Dentigerous cysts showed well-defined outline at 81.6%, but unicystic ameloblastomas showed well-defined outline at 53.1% and moderate-defined outline at 46.9%. In both lesions, the mandibular 3rd molar was the most frequent causative tooth. Average of distance between the cemento-enamel junction and lesional wall attachment of the causative tooth was longer in unicystic ameloblastomas than in dentigerous cysts. Severe displacement of causative tooth was more frequent in unicystic ameloblastomas at 62.5% than in dentigerous cysts at 23.7%. Dentigerous cysts showed homogeneous lesional radiolucency at 89.5%, but unicystic ameloblastomas showed inhomogeneous lesional radiolucency at 53.1%. Root resorption of adjacent tooth and displacement of mandibular canal were more frequent in unicystic ameloblastomas at 65.2% and 61.5% than in dentigerous cysts at 15.8% and 38.1% respectively.

• Imaging Science in Dentistry
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• v.35 no.1
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• pp.47-50
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• 2005

Purpose : To acquire the useful diagnostic information through the analysis of the clinical and radiological characteristics of mandibular unicystic ameloblastoma. Materials and Methods : The researchers compared and analysed the clinical and radiological features of 79 cases of mandibular unicystic ameloblastoma confirmed by histopathlogic examination. Results : The results of our research showed that unicystic ameloblastomas occurred more frequently in males than in females and the incidence is the highest in the 2nd and 3rd decades. These lesions occurred most frequently in angle-ramus area, mandibular molar area, and anterior area in descending order respectively $68.4\%$, $24\%$, and $7.6\%$. These lesions had smooth ($54.4\%$) rather than undulating ($45.6\%$) borders. These lesions showed well- defined borders in $59.5\%$ among all the cases. Root resorption and loss of lamina dura were observed as $55.7\%$ and $58.5\%$ respectively. Displacement of mandibular canal was observed in $55.9\%$ among all the related cases. Internal pattern of lesional radiolucency was observed as even ($49.4\%$) or uneven ($50.6\%$). Conclusion : These results would be helpful in diagnosing of mandibular unicystic ameloblastoma. (Korean J Oral Maxillofac Radiol 2005; 35 : 47-50)

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.2
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• pp.160-166
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• 1991

In 1977, Robinson & Martinez described a distinct varient of ameloblastomas in which the response to curettage was found to be favorable, with a recurrence rate of 25%. They referred to this varient as unicystic ameloblastoma. Unicystic ameloblastoma occur most commonly in the second and third decades of life, which is considerablly younger than the average age of discovery for the classical ameloblastoma. For the accurate histopathological diagnosis of the unicystic ameloblastoma, the specimen obtained the excisional biopsy, complete enucleation or incisional biopsy from the multiple site of the lesion. The purpose of this report is to review of the literature and to present three cases in which an unicystic ameloblastoma appear to be arising in the wall of a dentigerous cyst.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.29 no.2
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• pp.140-144
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• 2003

Ameloblastoma is cytologically a benign tumor, but is clinically characterized by infiltrative growth and high recurrency. The criteria for surgical treatment of ameloblastoma has not yet established and it is generally accepted that ameloblastoma be treated differently based on clinical types. The purpose of this paper is to consider effectiveness of enucleation in large-sized intraosseous ameloblastoma that has treated more frequently by radical treatment. 39 cases of the intraosseous ameloblastomas were treated by enucleation in the department of oral and maxillofacial surgery of Yonsei University, dental college from February 1990 to January 2001. 25 cases were selected because they were large in size that could produce facial disfigurement or pathologic fracture of jaws. They were radiographically characterized by the cortical bone that was expanded or eroded locally and histopathologically by 19 solid ameloblastomas and 6 intramural type of unicystic ameloblastomas. Among the 25 cases, 4 cases - 3 solid ameloblastomas and 1 intramural type of ameloblastoma - recurred. Recurrence rate was 16%. The compact bone which is not invaded by ameloblastoma was used as surgical margin of enucleation with accompanying chemical cauterization for killing the residual tumor cells. This may have been the reason for the low recurrence rate. So, it is considered that enucleation and long-term follow-up enable the large-sized intraosseous ameloblastomas that were characterized by almost destroyed cancellous bone and expanded or discontinued cortical bone to treat minimizing facial disfigurement and masticatory dysfunction and sociopsychological impact produced by radical treatment. I recommend that the large-sized intraosseous ameloblastomas without involvement to the surrounding soft tissues be first treated by enucleation.

• Imaging Science in Dentistry
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• v.46 no.3
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• pp.147-157
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• 2016

This review article aimed to introduce a category of jaw lesions associated with impacted tooth. General search engines and specialized databases such as Google Scholar, PubMed, PubMed Central, MedLine Plus, Science Direct, Scopus, and well-recognized textbooks were used to find relevant studies using keywords such as "jaw lesion", "jaw disease", "impacted tooth", and "unerupted tooth". More than 250 articles were found, of which approximately 80 were broadly relevant to the topic. We ultimately included 47 articles that were closely related to the topic of interest. When the relevant data were compiled, the following 10 lesions were identified as having a relationship with impacted tooth: dentigerous cysts, calcifying odontogenic cysts, unicystic (mural) ameloblastomas, ameloblastomas, ameloblastic fibromas, adenomatoid odontogenic tumors, keratocystic odontogenic tumors, calcifying epithelial odontogenic tumors, ameloblastic fibro-odontomas, and odontomas. When clinicians encounter a lesion associated with an impacted tooth, they should first consider these entities in the differential diagnosis. This will help dental practitioners make more accurate diagnoses and develop better treatment plans based on patients' radiographs.

• Imaging Science in Dentistry
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• v.35 no.4
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• pp.207-213
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• 2005

Purpose: To classify and describe the characteristic features of MRI of some ameloblastoma variants. Materials and Methods: The MR images, CT images, and panoramic radiographs in 5 cases were retrospectively examined as follows. First, the contents of ameloblastomas were devided into two portions of either solid or cystic components on the basis of MR signal intensities. The signal intensity within the solid or cystic portions was classified as homogeneous or heterogeneous. Next, the characteristic internal feature of the lesion on T1W1 or T2WI was described. The signal intensities were classified into low, intermediate, slightly high, high, and strong high signal intensity. Results: Unicystic lesion showed homogeneous high signal intensity (SI) on T2W2 and the rim enhancement of the surrounding area including the mural nodule and the thick wall except the central portion on Gd- T1W1. Solid type revealed heterogeneous and high SI area with strong high SI area on T2W2. On Gd- T1W1, the area corresponding to the low signal spot on T1W1 and the strong high signal spot on T2W1 showed low SI. Hybrid type showed slightly enhanced capsular structures and low SI for the round bony septa and the areas connecting the mixed and cystic lesions on T2Wl and Gd-T1W1. Conclusion: MRI could easily assess the relationship between the mixed and cystic findings in ameloblastoma.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.1
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• pp.43-48
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• 2004

Purpose: Among the various surgical methods used for the effective treatment of cystic lesion in the jaws historically, decompression procedure has some of superior prognosis compare to direct enucleation. In order to propose the efficacy of decompression we performed this retrospective study to compare decompression procedure with one-stage enucleation in clinical results and prognosis. Patients and Methods: We reviewed 175 patients who had been histopathologically diagnosed cystic lesions from 1996 to 2000 in our department. Patients who had been received decompression alone or secondary enucleation after decompression were 31 cases, and enucleation alone were 144 cases. The age and sex of the patients, the area, size, and histological type of the lesions, and detailed operation and complications including recurrence were investigated. The minimal follow-up period was 2 years. Results: In 31cases of decompression, male patients were 22cases(71%) similar to male predilection(62.3%) in total 175 cases. Cystic lesions were developed evenly in all age groups totally. Decompression was mainly performed in teenagers but enucleation was used in elder decades. In decompression cases the lesions were located in mandibular posterior, maxillary posterior, mandibular anterior, and maxillary anterior in order, which had some differences in total and enucleation cases. In enucleation cases, less than 3cm in size was 77.1% but larger than 3cm was 93.5% in decompression cases. Histopathologically, dentigerous cysts(54.8%), unicystic ameloblastomas(16.1%), and odontogenic keratocysts(12.9%) were seen in decompression cases and no recurrence or metaplasia and infection was observed. On the other hand, permanent tooth loss, numbness, recurrence, and so on were accompanied after enucleation. Conclusion: Although decompression procedure has disadvantages such as many of visiting times and slow recovery of the surgical defect, decompression is the best choice of treatment for large cystic lesions of the jaws, because it prevents functional and cosmetic defect, allows bone regeneration, and makes easy secondary enucleation.