Metastatic tumors in oral cavity are rare, where their prognoses are considered to be extremely poor. Unless recognizing its primary origin, pathologic diagnoses for metastatic cancer have been troublesome for oral pathologists. This retrograde analysis was aimed at providing practical suggestion for the diagnoses of metastatic cancers to oral and maxillofacial region. We reviewed 20 patients diagnosed as metastatic cancers to oral cavity from 1991 to 2007. The patients were classified according to their clinical and histologic findings. We also reviewed 19 patients of mucoepidermoid carcinoma and 16 patients of adenoid cystic carcinoma to compare with those of metastatic cancers. Immunohistochemical staining for CK 5/6, CK 17, TTF-1, CEA was performed for differential diagnosis. Histologically, 20 cases compromised 11 cases of adenocarcinoma, 5 cases of undifferentiated carcinoma, 3 cases of squamous cell carcinoma, and one papillary carcinoma. The lung was the most common site for primary site (5/20), followed by the breast (2/20). In metastatic adenocarcinoma, TTF-1 positive cases were one lung cancer and a rectal cancer, and carcinomas from breast and rectum showed CK5/6 positive reaction. CEA was expressed in gastric and rectal carcinomas. In 19 cases of mucoepidermoid carcinoma, 13 cases (68.4%) are CK5/6 (+). In 16 cases of adenoid cystic carcinoma, 11 cases (68.8%) showed the positive reaction for CK5/6. TTF-1 is an antibody to show high sensitivity and specificity for lung adenocarcinoma, therefore, TTF-1 is helpful to make a diagnosis of metastatic adenocarcinomas from lung. Adenocarcinomas originated from salivary glands show high CK5/6 expression, but metastatic adenocarcinomas, except of those from breast and rectum, show no CK5/6 expression, lending support that CK5/6 may be useful to differentiate metastatic adenocarcinomas from carcinomas of salivary gland origin.

The cylindrical gear in power window motor assembly is important to doors of automobile. This study is performed for purpose of getting a manufacturing technique instead of large quantities import and small cavity mold production. This multi-cavity cylindrical gear is produced under five procedures. The first, mold design of massproduction, the second, making a CAE model for mass-production, the third, manufacturing of sample mold, the fourth, trying-out and measuring of 3 dimensional design, the fifth, acquisition of data analysis and mold modification. Among them, analysis of mass-production using CAE, design and manufacturing of multi-cavity are successfully performed. In the results, it is concluded that mold for one gate and six cavity based on hot-runner is suitable for making a cylindrical gear.

High temperature dielectric constants of the various ceramic materials have been measured using cavity perturbation method. The measurements were applied to refractory, traditional and fine ceramic powder compacts from room temperature to . Calibration constant in the equation suggested by Hutcheon et al., was determined from the dielectric constants of reference specimen (teflon and alumina) at room temperature. From these results, informations on the refectory materials were obtained for the microwave kiln design and understanding of the microwave heating effects of ceramics have been improved.

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

Matrix metalloproteinases(MMPs) are involved in the degradation of extracellular matrix, which is re lated to infiltrative growth and metastasis of tumor and are regulated by tisslle inhibitor of metalloproteinases(TIMPs) or cell adhesion molecllles such as E-cadherin and epidermal growth factor receptor (EGFR). The aim of this study is to evaluate the relationship between MMP-2, MMP-9 expressions and clinico-pathologic factors, 끼MP-1 ， TIMP-2, EGFR and E-cadherin expressions. lmmunohistochemical stains were perfom1ed on 55 cases of squamous cell carcinoma of the ordl cavity and the results were as follows. MMP-2 and MMP-9 expressions were noted in 30(54.5%) and 22(40.0%) of 55 cases, TIMP-1 and πMP-2 in 21(38.2%) and 33(60.0%), and E-cadherin and EGFR expressions in 35(63.6%) and 26(47.3%) of 55 cases, respectively. MMP-2 expression rdte was slightly higher 띠 cases without recurrence, and 끼MP- 2 expression rate was slightly higher in cases showing more inftltrative growth pattem. 까1e expression rate of EGFR was higher in cases with well differentiation(p=0.OO47), but no posi디ve relationship between the expression rate of Ecadherin and histologic grade was found. Cases with positive reaction for MMP-9 showed an increasing tendency of nega디ve reaction for TIMP-1. π1e expression rate of MMP-2 was higher in cases with positive reaction for E-cadherin and EGFR with no statistical significance. 까1e expression rate of MMP-9 was significantly higher in cases with positive reaction for E-cadherin(p=0.022l). These results suggest that MMP-2, MMP-9, TIMP-1 and TIMP-2 expressions are involved in the development of oral squamous cell carcinomas, but MMP-2, MMP-9, 끼MP-1 ， and 끼MP-2 expressions might not seem to be a useful prognostic factors because there were no significant relationship between clinicopathologic parameters. EGFR expression showed positive correlation with low histologic grade, so EGFR expression could be regarded as a good prognostic factor. In the progression of sqllamous cell

This study investigates the stress distribution in a transversely isotropic medium containing a spheroidal cavity where the medium is under uniaxial tension in z;:iirection in one case and pure shear in the plane of isotropy in another case. The technical approach used in this study combines exact analytical and numerical methods. The exact analytical method is based upon three potential funct.ions taken in terms of the Legendre associated functions of the first and second kind. The numerical method is based upon the finite difference approach. Numerical results concerning the two loading conditions with fi ve anisotropic materials are presented.