Ameloblastoma is an odontogenic tumor characterized by various sites of metastasis, malignant transformation, and a high recurrence rate over time. Ameloblastic carcinoma(AC) is the term reserved for an ameloblastoma with histologic evidence of malignancy in the primary tumor. AC is classified into two types: most ACs occur de novo, and only few cases of malignant transformation of ameloblastoma become apparent. Here, we report a case of AC, arising from recurrent acanthomatous ameloblastoma on the maxillary sinus, in a 60-year-old male patient. The mass was first diagnosed as acanthomatous ameloblastoma; subsequently, surgical curettage was performed thrice while partial maxillectomy was performed twice. On the fifth recurrence, the tumor was identified as AC.

Pseudosarcomatous fibromatosis (PSF), also known as nodular fasciitis and pseudosarcomatous fasciitis, is a rare, benign proliferation of fibroblasts and myofibroblasts. It is often misdiagnosed as sarcoma because of its characteristic rapid progression, leading to unnecessary and aggressive surgery. Here we report a case of PSF found in the masseter muscle in a 26-year-old female. The mass that could be misdiagnosed because of its rapid growth characteristics was surgically excised by an intraoral approach and diagnosed as PSF by histopathologic examinations.

Ameloblastoma is a benign odontogenic tumour of epithelial origin and comprises 1% of maxillomandibular tumors or cysts. The incidence of pathological changes such as ameloblastoma from the follicle of impacted third molar was reported to have low incidence. However, there are many reports that asymptomatic third molars are related with various pathological conditions. A case of ameloblastoma secondary to third molar extraction and subsequent sagittal split ramus osteotomy (SSRO) had not been reported. At the right ramus area, radiolucent lesion had been noted at 6 years after the surgical extraction of the third molar followed by SSRO for the mandibular prognathism. The lesion was proved to be the basal cell type ameloblastoma. There had been no significant bony lesion before or 1 year after the SSRO. The tumour was successfully removed and there was no evident recurrence at 4 year of the follow up after the removal of the ameloblastoma. There are some reports suggesting the pathologic potential of the pericoronal tissues of impacted third molars to develop odontogenic keratocysts and ameloblastomas. The current case reports a rare possibility of ameloblastic change at the site of uneventful healing after third molar extraction and orthognathic surgery.

Carcinoma ex pleomorphic adenoma (Ca ex PA) is an uncommon malignant tumor. It is an aggressive salivary carcinoma, arising from a primary or recurrent benign pleomorphic adenoma (PA). The most common clinical presentation of Ca ex PA is a firm mass in the parotid gland. Here we report a case of Ca ex PA, arising from a recurrent benign PA in the right parotid gland, in a 70-year old female patient. The lesion was first diagnosed as a PA and a superficial parotidectomy was performed. Re-operation was performed for recurrent PA. The second recurrence was diagnosed as Ca ex PA.

Pilomatricoma is the second most common benign dermal-subcutaneous tumor of the head and neck region, after epidermoid cyst, originating from the outer sheath cells of the hair follicle. It can be easily treated with surgical excision. However, it is a relatively unknown skin lesion to maxillofacial surgeons. Therefore, we report a case of pilomatricoma occuring inferolateral area of the parotid gland in a 54-year-old man; with a review of the relevant literature.

Mucormycosis generally presents as an acute infection manifesting in rhinocerebral, pulmonary, gastrointestinal, cutaneous, or disseminated forms. Fungal invasion to the arteries can reduce blood supply by thrombi formation inside the blood vessels, leading to necrosis. Fungal infection usually initiates in the upper turbinate, paranasal sinus, or less commonly in the palate or pharynx. Here we report an unusual case of mucormycosis in the maxilla of a 75-year-old man and present a review of the literature.

This study was performed to improve the efficiency of guided bone regeneration by adapting the tissue-engineered bone regeneration approach. The PHBV-collagen nonofibrous membranes cultured with rat calvarial periosteum derived cells in osteogenic culture medium for 7 days were applied to 5 x 2mm size artificial rat tibial defects for 3weeks and evaluated its efficiency as an alternative cell engineered membrane for effective guided bone regeneration by routine histological observation. The defects covered with cell attached PHBV-collagen nanofibrous membrane complexes showed favorable bone repair compared to both membrane non-covered control and membrane only covered group without specific side effects. These findings suggest that the favorable guided bone generation can be achieved by adapting the tissue engineered bone regeneration approach using PHBV-Collagen nanofibrous membrane scaffold.

The PHBV nonofibrous membrane fabricated by electron-spinning method for tissue engineered bone regeneration scaffold was evaulated in terms of cellular prolieration and cryopreservation efficiency. The rat calvarial periosteum derived primary cells were cultured with PHBV nanofibrous membranes and analyzed the cellular proliferation and differention fashion and cryopreservation potential by in vitro MTT assay as well as ALP staining and Alizarine red staining with or without cryopreservation for 2 weeks. The rat calvarial periosteum derived primary cells cultured with PHBV nonofibrous membrane showed favorable proliferation and alkaline phosphatase activity with numerous mineral nodule formation regardless of cryopreservation, even though its efficiency was slightly decreased in cryopreserved condition. These findings suggest that PHBV nanofibrous membrane can be applicable as an efficient cell engineered membrane for guided bone regeneration or scaffold for tissue engineered bone regeneration.

Mucoepidermoid carcinoma, a malignant neoplasm of salivary gland, rarely arises within the jaws. Differential diagnosis should include an odontogenic cyst because the central mucoepidermoid carcinoma usually reveals either an unilocular or multilocular radiolucency with hyperostotic border. Long-term follow-up is needed due to late recurrence and clinical slow progress like other salivary gland tumors. We would like to report an unusual case of central mucoepidermoid carcinoma with a review of literature.

Dermoid and epidermoid cysts in the oral cavity are uncommon and account for less than 0.01% of all oral cysts. The large majority of cases arise in the floor of the mouth and there are rare in other sites. We would like to report an unusual case of epidermoid cyst at the buccal mucosa in a 66-year-old male with a review of literature.

Bioactive peptides function effectively with a minimal amount compared to proteins. Recently SPARC related modular calcium binding 1 (SMOC1) has been implicated in regulating osteoblast differentiation and limb and eye development. In this study we synthesized a peptide covering 16 amino acids derived from the extracellular calcium binding (EC) domain of SMOC1, and its effects on proliferation and osteoblast differentiation of human bone marrow mesenchymal stem cells were examined. Treatment of SMOC1 peptide did not modulate proliferation of BMSCs. However, mineralization of BMSCs was significantly increased with a dose dependent manner. Consistently expression of osteoblast differentiation marker genes including type 1 collagen and osteocalcin was also dose dependently increased. Taken together, these results suggest that peptide derived from the EC domain of SMOC1 recapitulates at least partially osteogenic function of SMOC1.

Multinucleated giant cells appear in a variety forms in different types of oral lesion. However, their nature is still not well understood. Thus, to address this issue, the immunohistochemical characteristics of inflammatory giant cells (Langhans’ giant cells in lesions of tuberculosis and foreign body giant cells in odontogenic keratocysts and squamous cell carcinomas) and tumor giant cells in central giant cell granulomas were compared with those of osteoclasts, the normal giant cell, using a panel of macrophage and osteoclast marker antibodies, such as calcitonin receptor (CT-R), c-Src, Cathepsin K (Cath-K), CD14, RANK, and c-fms. The foreign body giant cells around cholesterol clefts in inflamed odontogenic keratocysts revealed more macrophage-like characteristics than the foreign body giant cells resorbing keratin pearls in squamous cell carcinomas. As such, both cases of foreign body giant cell exhibited immunoreactivity for the macrophage markers, such as CD14, RANK, and c-fms, yet only the latter case exhibited immunoreactivity for the osteoclast markers, such as CT-R and c-Src. Moreover, both cases of foreign body giant cells were positive for TRAP activity, yet negative for Cathepsin K activity. In contrast, the other inflammatory giant cells, Langhans’ giant cells, exhibited immunoreactivity for both the macrophage and osteoclast markers, yet were negative for TRAP activity. Meanwhile, the giant cells in the central giant cell granulomas reacted positively to both the macrophage and osteoclast markers, and were also positive for TRAP activity. Accordingly, these findings suggest that the immunoprofiles of giant cells in oral lesions vary according to the nature of the lesion, despite shared osteoclast and macrophage characteristics. Furthermore, the giant cells in tumorous lesions closely associated with bony destruction revealed more osteoclastic characteristics and their enzyme components were different according to the nature of the lesion

The central granular cell odontogenic tumor is a rare benign odontogenic neoplasm of uncertain hisotogenesis characterized by varying amounts of eosinophilic granular cells and apparently inactive odontogenic epithelium with variable presence of calcified tissue. We present a case of central granular cell odontogenic tumor involving the maxilla of 35-year-old man with immunohistochemical characterization of granular cells. In microscopic view, the granular cells densely packed in sheets and lobules with abundant eosinophilic, granular cytoplasm and eccentric round-to-ovoid nuclei revealed immunoreactivity for vimentin, α1-antitrysin and CD68, and NSE but not for cytokeratin and S-100 protein while the interspersed odontogenic epithelial cells were positive for cytokeratin only. Granular cells also revealed strong PAS staining. Numerous concentric structured round to ovoid calcified aggregates were also noted. The lesion was treated with excision without recurrence for 8 years. Our immuohistochemical staining findings also suggest that the granular cells of central granular cell odontogenic tumor are mesenchymal in origin with possible histiocytic differentiation

Previous ly we have s hown that fï brob last• growth factor-2 (FGF-2) and dexamethasone (Dex) in combination strongly stimulate both p l 이 i fe rati o n a nd differe nt iation of mesenchymal stem cells (MSCs) into osteoblasts and adipocytes, In the present s tudy we invesL igaLed whether inhibition 01' FGF-2 and Dex-induced adipogenic differentiation of bone marrow derived s Lem cells (BMSCs) by GW9662, an antagoni s t of proxisome proliferators-activated receptol γ (PPARy) which plays a key role in ad ipogenic differentiation , enhances proliferation and osteoblastic differentiation of BMSCs Proliferation 01' BMSCs t reated wi 네 FGF-2 a nd Dex was further increased by GW9662 up to 9,7, 10,6, and 7,2% at 3, 5, and 7 days of cul Lu re , Expansion of BMSCs with FGF-2, Dex and GW9662 followed by osteoblastic different iation showed that osteoblas tic differentiation 01' BMSCs was in creased by 37 % (p=O, 01) compared to those expanded with FGF-2 and Dex, ln contrast , ad i pogenic di fferenti a tion of FGF-2 and Dex-expanded BMSCs was substantially reduced to 14% (p=O, 036) by GW9662, Taken toget her , these resul ts demonstrate that FGF-2 and Dex in combination with GW9662 f ur t her stimu late proliferation 01' BMSCs and those cells expanded with these factors acquire enhanced potentiaIs to be dif ferentiated i n to osteoblas ts

As a pa rt 0 1' the effort to develop a suitable scaffold for tissue-engineered bone regene ration, we modified calcium metaphosphate(CMP) ce ramic with 5 mol% Na20 or K20 to improve t he biodegradability and evaluated their effi ciency as a biodegr adable scaffold for ti ssue-engineered bone regeneration. The macroporous αiIP ceramic blocks incor porated with 5 mol% Na20 or K20 were prepa recl to have average pore size of 250 um in an inte rconnectecl framework structure The influ e nce of inco r pora tecl 5 mol% Na20 or K20 on cytotoxicity‘ cellular attachmont and t heir clifferentiation was evaluated by in vit ro analyzing sys tern. res pectively. The bioclegradability, histocompatibility, and osteogenic effect by cell-scaffolcl co nstruc ts were evalua ted by im plantation of them into subcutaneous pouches of SD-rats 0 1' SCID ITllce The incorporation of 5 mol% Na20 or K20 causecl clecrease of compressive strength without improving of biodegr adabili ty . The moclifi ed scaffolcls revea led no cy totoxic and excell ent biocompatability but osteogneic effect was recluced compa red to pure CMP ce ramic porous blocks . These res ul Ls s ugge::;t tha t the incorporation of 5 mol% Na20 0 1' K20 into pure CMP is not effective for improv ing effï ciency 0 1' scaffolcls fo1' tissue-engineered bone regeneration in terms of bioclegradabi li ty‘ physical s trength . a ncl osteogenic rege ne ra tive effect