Abstract : Myoepithelial cells are the most unique smooth muscle and lie between the glandular epithelial cells and basal lamina of the secretory terminal portion of a variety of ecocrine glands including salivary, mammary, lacrimal and sweat glands. These myoepithelial cells have several characteristic features which differ from ordinary smooth muscle cells ; they are believed to be epithelial in origin and are usually stellate in form rather than simple spindle-shaped. The function of the myoepithelial cells are thought to be expelling the secretion from the secretory terminal portion to the duct by their contraction ability. They are also of particular importance in understanding the pathogenesis of the exocrine glands ; the involvement of myoepithelial cells in carcinogenesis has been indicated.

 The profile of myoepithelial cells varied considerably from gland to gland. This review is to introduce the fine and three-dimensional structures and functions of the myoepithelial cells in the salivary and several other exocrine glands which were elucidated by using immuno-histochemistry and scanning and transmission electron microscopy.

Abstract : Using drug delivery denture, oral health of teeh and gingiva was maintained by controlled releasing of tannin and fluoride. In this report, green tea powder was added in a pocket of mucosal surface of partial denture or complete denture, and tannin released. Several months later, dental and tong plaque were disappeared, and tong became look red, and bad breath disappeared.

Abstract : The present study was carried out to evaluate a system established by the author to prevent intracanal breakage of endodontic files. It consists of four factors : file-selection, file-maintenance, file-handling, and predetermined periods of use for endodontic files of all sizes. The system underwent a seven year clinical use at the author’s clinic. During the seven year period, 4,075 files were discarded after preparation of 5,357 root canals (0.76 per root).

 No breakage was observed in all the files.

 It was concluded that this system was found to be most effective against clinical breakage. Adoption of this system, at both private dental clinics like the author’s and larger dental clinics, will save labor in the process of removing the separated instrument fragment from the inside of the root canal.

Abstract : The purpose of this study was to evaluate the shape, the radiopacity, and the composition of Calcium Hydroxide Points (CH Point) and to determine the pH level in water and morphological change of root surface after removed CH Point.

 The results were as follows :

 1. The shape of CH Point met the ISO standard No. 6877-4.4.

 2. The radiopacity of CH Point was low. The radiopacity of＃80 CH Point was as same as 1080 μm thickness of Aluminum.

 3. The CH Point contained calcium hydroxide under the X-ray diffraction.

 4. In 1 day, pH rapidly increased above pH10. In replaced water group, pH decreased every period but pH kept up 7 days in non-replaced water group.

 5. The CH Point had no remnant of calcium hydroxide on root surface.

Abstract : Recently, Ni-Ti files are used in endodontic therapy, and many investigators have reported that characterization of Ni-Ti files. However, many clinicians are perplexed to select proper various newly Ni-Ti files. In this study, we examined the accidents when using Ni-Ti files : Quantec and ProFile, on root canal enlargement. The perforation of canal wall occurred using＃9 Quantec, 2 canals per 20 root canals, however, no perforation was observed using ProFile. The broken instruments were observed 2 cases on using Quantec and 1 case on using ProFile, respectively. The dentin muds at apical area were produced in using both Ni-Ti files, 3 canals in Quantec and 1 canal in ProFile, respectively. When using Ni-Ti files, we have to know the characterization and prevention of those accidents.

Abstract : Usually vertical fractured molarteeth are extracted. These dayes adhesive materials to enamel and dentin are improved and besides the new method mixing 3 kinds of antibiotic is effective for preventing pulp from contamination. By useing adhesive materials and 3 kinds of antibiotic it had succesed not to extract vertical fractured molar. This tooth had been received the endodontic treatment and had been restored with gold cast crown. For 2 years any problems have not appeared.