1.Finite element analysis of fin-type implant fixtures.
Su Gwan KIM ; Chang Gil CHON ; Gab Woon HWANG ; Byung Ock KIM
Journal of the Korean Association of Oral and Maxillofacial Surgeons 2003;29(1):14-25
The purpose of this study was to analyze the stress pattern in different bone densities surrounding fin-type implant fixtures under the vertical and inclined loads (30 ) of 200N. Von-Mises stress, the pricipal stress, and the displacement on the implant fixtures under the loads were calculated by using the finite element method. Four different types of bicon implant fixture were used for this study. The geometries of implant fixtures to develop the model were used by a sales brochure and profile project. Three-dimensional finite element model of the mandible was developed with 6.0 mm implant in diameter wurrounded by approximately 2.5 mm of bone. Bone densities were classified according to the elastic modulus of the tree. The finite element program MSC PATRAN (MSC, Software Corp., USA) were used for analysis of stress distribution. The value of the Von-Mises stress, the pricipal stress, and the displacement on the implant fixtures under the vertical and inclined loads were decreased when the diameter of implant fixture was increased, and increased when the elastic modulus was decreased. The stress on implant fixture under the vertical and inclined loads was distributed through the length of implant fixtures in D3 and D4. The distribution of stress was influenced by the direction of loads. In the wide diameter of implants, the stress was developed at outer surface of bone. In conclusion, this study suggest that stress developing on the peri-implant tissues might be influenced by the dimension of implant, elastic modulus of bone, and direction of loads.
Bone Density
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Commerce
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Elastic Modulus
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Finite Element Analysis*
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Mandible
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Pamphlets
2.A Case of Cecal Endometriosis Presenting as Subepithelial Tumor.
Min Sik HWANG ; Young Don KIM ; Sa Young SHIN ; Jae Hyuck JUN ; Jong Sam HONG ; Dae Woon EOM ; Gab Jin CHEON
The Korean Journal of Gastroenterology 2016;68(4):214-217
Endometriosis is a benign gynecologic disease, characterized by the presence and growth of functional endometrial-like tissue outside uterus. This ectopic endometrial tissue is most commonly found in the peritoneum, ovaries and uterosacral ligaments, but extremely rarely there is involvement of the appendix or cecum. Here we report a case of cecal endometriosis presenting as a subepithelial tumor diagnosed by surgical excision.
Appendix
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Cecum
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Colonic Neoplasms
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Endometriosis*
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Female
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Genital Diseases, Female
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Ligaments
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Ovary
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Peritoneum
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Uterus