Plunging ranula is a mucous retention cyst with extension below to the mylohyoid muscle. It can occur by an extravasation of saliva from the salivary gland due to trauma or obstruction of the duct. Fluid from the obstructed gland penetrate through the defect of mylohyoid muscle or through the posterior edge of mylohyoid muscle, and spreading to the cervical area. The “tail sign” has been widely reported as pathognomonic for their diagnosis. It indicates the communication between the collapsed sublingual and submandibular space over the posterior edge of the mylohyoid muscle. In this case, in addition to simple ranula in the right floor of mouth, MRI findings showed homogeneous contrast enhancement in front of the right cervical carotid artery and in the deep part of sternocleidomastoid muscle, but tail sign was not observed. Therefore it was clinically diagnosed as a branchial cleft cyst and was removed through surgical procedure. As a result of the final pathologic biopsy, the lesion, which has been suggested to be simple ranula in the floor of mouth, was diagnosed as reactive pyogenic granuloma, and the cervical lesion was diagnosed as a plunging ranula. This is a case report in which these two lesions are decided to have been separated from one before surgery. This report indicate that plunging ranula can be observed without tail sign and how to make an accurate diagnosis of plunging ranula by reporting misdiagnosis case.

Development of squamous cell carcinoma around dental implants is an uncommon clinical manifestation with only a few cases described in the literature. Recently, we observed primary squamous cell carcinoma that developed from leukoplakia around dental implants. We report this case to emphasize the importance of careful oral examination, for implant surgery has to be preceded by thorough evaluation of oral mucosal conditions.

Nodular fasciitis is defined by the World Health Organization as a benign proliferative fibroblastic lesion. It was first described in 1955 by Konwaler et al. and also known as “nodular pseudosarcomatous fasciitis” and “infiltrative fasciitis”, which reflect the lesion’s rapid growth, dense cellularity, alarming mitotoic activity and lack of circumscription. Here, we report a case of nodular fasciitis, which appeared as subcutaneous mass of right perizygoma area in 40-year-old Korean female. She had no history of trauma or cosmetic surgery related with the lesion. She disclosed that the mass grew rapidly for last 2 months. Computed tomography showed relatively well-defined spherical mass with 1.2 cm in diameter. Under local anesthesia the mass was resected by intraoral approach. The histological examination revealed a relatively poor-dermacated mass with high cellularity, which was composed with infiltrative spindle-shaped cells without accompanying inflammatory reactions. The tumor cells were partially positive for α-smooth muscle actin and β-catenin, but negative for cytokeratin AE1/3, S-100, desmin, and CD34. Therefore, the lesion was pathologically diagnosed as nodular fasciitis. Although nodular fasciitis is known to pseudosarcomatous benign reactive lesion, the clinician need to follow up the patient periodically. The reasons are as follows; Nodular fasciitis may accompany nuclear accumulation of β-catenin, which imply neoplastic process rather than reactive process of the lesion. Moreover, it has many histological similarities with inflammatory myofibroblastic tumor which have malignant transformation tendency. Further research for mesenchymal tumor could help our understanding for the disease entity of nodular fasciitis

Osteogenic sarcoma is primary malignant bone tumor. It can arise de novo or from the benign precursors lesions, like Paget’s disease, giant cell tumor, chronic osteomyelitis, osteoblastoma, and fibrous dysplasia. Here, we present a case of osteogenic sarcoma arising from florid osseous dysplasia appearing as a rapidly growing bony bulging mass in 44‐year‐old Korean female who had at first been non‐symptomatic, but later suffered from the numbness of chin and lower lip. The radiologic images revealed the mixed radiopaque‐ radiolucent intraosseous lesions throughout the mandible, which were diagnosed as florid osseous dysplasia pathologically. But only after 6 months, the lesions were substituted by the radiological ill‐defined diffuse bony sclerotic lesion with bone destruction, accompanying the interrupted periosteal bone formation, which were pathologically diagnosed as osteogenic sarcomas. These serial clinicopathologic changes imply the malignant progression of florid osseous dysplasia rather than the collision of benign condition, florid osseous dysplasia and malignant tumor, osteogenic sarcoma. The possibility for fibro‐osseous lesion of the jaw as premalignant lesion should not be overlooked; therefore, periodic check‐ups for the lesions are necessary. Proper evaluation and interpretation for clinical neural symptom and radiologic change of bone density may lead to the correct differential diagnosis and therapeutic intervention.

Artemisia scoparia (A. scoparia), perennial herb is indigenous to Korea and has been traditionally used in liver damage. We investigated the effect of the essential oil obtained from A. scoparia on apoptosis of KB cells. Cytotoxicity and cellular DNA content were analyzed by MTT assay and flow cytometry, agarose gel electrophoresis, and Hoechst 33258 staining. The caspase-3 and poly (ADP-ribose) polymerase (PARP) proteins were estimated by Western blotting method. We found that the essential oil induced the apoptosis of the KB cells by concentrations of 0.4 to 0.2 mg/ml which was verified by DNA fragmentation, apoptotic bodies, and the sub-G0/G1 ratio. The essential oil also transient caspase-9 and caspase-3 activity and cleavage of PARP in KB cells for 24 h. The essential oil-induced apoptotic cell death was accompanied by up-regulation of Bax and down-regulation of Bcl-2. In conclusion, we demonstrated that the essential oil of A. scoparia induces apoptosis in KB cells

Fibro-osseous lesion(FOL) has been known a lesion that normal bone is replaced by cellular fibrous connective ti ssue and nonfunctional bone, FOL has been classified and revised by several investigators and World Health Organization(WHO) , For correct diagnosis and treatment, it is necessary to classify FOL precisely, Compared to the class ificat ion by WHO in 1992‘ the new version of 2005 makes it simpler to classify , Therefore, the aim of this study is classifying FOL by the WHO classification in 1992 and compare it with the new ve1'sion in 2005 The material was 1'e tl‘ ieved f l'om the cases which were diagnosed as FOL from 1992 to 2005 in the Department of Oral Pathology, Yonsei University College of Dentistl'Y, Clinical, rad iological and pathological observations were conducted for this study Comparing WHO classifi cation in 1992 with the one in 2005, there were no differences regarding clini cal, radiological a nd hi s tological f indings in each classified disease entity of both osteogenic neoplasm and non neoplastic bone lesion , Hence, the new classification by WHO in 2005 would be a useful yardstick for correct diagnosis and treatment , For the differential diagnos is between osteogenic neoplasm and non neoplastic bone lesion, it is important to observe the degree of cell ularity microscopi cally and definiteness of the border radiographically,

Combined epithelial odontogenic tumors are very rare and represent hybrid lesion comprising adenomatoid odontogenic tumor intermixed with calcifying epithelial odontogenic tumor. The authors present 3 cases of combined epithelial odontogenic tumor which contained diagnostic areas for both adenomatoid odontogenic tumor and calcifying epithelial odontogenic tumor. Their behaviour and histogenesis were discussed.

Squamous cell carcinoma comprises about 95% of oral cancers. 까le gene디C 없mage in carcinogen-exposed fields is accumulated to transforrn norrnal mucosa in dysplas디c tissue and fmally invasive carcinoma through multistep process. This carcinogenic process has been a cause of the development of secondary tumors after the removal of primary carcmoma. πle improvement of therapeutic modalities of oral cancer has driven into the increase of multiple cancer occurrence in head and neck region. We experienced 3 pa디ents who had mul디ple squamous cell carcinomas in oral cavlty. π1ÎS study aimed to report multiple pr따laπ squamous cell carcinoma by clinical and pathologic examination and to discuss their molecular mechanism

World Health Organization(WHO) revised the classification of neoplasms and other tumours related to odontogenic apparatus in 1992. The aim of this study was to classify the odontogenic tumors of Korean according to the WHO Histologic classification. A total of 271 cases were reviewed for the study which were diagnosed as odontogenic tumors at the department of Oral Pathology, Yonsei University College of Dentistry for the period from Jan. 1997 to March 2003. Clinical and pathology reports were reviewed & radiographic feature were examined. The following results were obtained : 1. Among 271 cases, 269 cases(99.3%) were diagnosed as benign odontogenic tumors, and the remaining 2 cases(0.7%) were malignant tumors, which were diagnosed as odontogenic ghost cell carcinoma and squamous cell carcinoma ex odontogenic cyst. 2. Four cases were not able to classify into the WHO classification. All of them were belonged to mixed odontogenic tumors; two cases of adenomatoid odontogenic tumor with calcifying epithelial odontogenic tumor, one case of adenomatoid odontogenic tumor with odontoma, odotogenic cyst and one case of ameloblastoma with immature odontoma. 3. The most frequent odontogenic tumour was odontoma(45.2%), followed by ameloblastoma (29.2%), odontogenic fibroma(9.2%) 4. One case of atypical amelobalstoma and one case of calcifying odontogenic cyst with ameloblastic fibroma were not able to subclassify histologically. 5. Male to female ratio of odontogenic tumors was 1.2:!. Odontogenic tumors mainly occured in the first and second decade, occurred twice as much as in the mandible than in the maxilla 6. The odontogenic tumors was discovered by routine oral x-ray examination, whereas the chief complaint of ameloblastoma were swelling, pain. 7. Ameloblastoma, adenomatoid odontogenic tumor, calcifying odontogenic cyst and odontoma were related to the impacted teeth and tooth displacement. The root resorption was frequently observed in ameloblastoma and calcifying odontogenic cyst.