A Study on the Application of Root Canal Sealer Containing Tetracalcium phosphate as a Base

Research Project

Project/Area Number	06454583
Research Category	Grant-in-Aid for General Scientific Research (B)
Allocation Type	Single-year Grants
Research Field	矯正・小児・社会系歯学
Research Institution	Osaka University
Principal Investigator	SOBUE Shizuo Osaka Univ.Faculty of Dentistry Professor, 歯学部, 教授 (60029973)
Project Period (FY)	1994 – 1995
Project Status	Completed (Fiscal Year 1995)
Budget Amount *help	¥5,200,000 (Direct Cost: ¥5,200,000) Fiscal Year 1995: ¥700,000 (Direct Cost: ¥700,000) Fiscal Year 1994: ¥4,500,000 (Direct Cost: ¥4,500,000)
Keywords	tetracalcium phosphate / oleic acid / eugenol / root canal fillings / 根管充填 / シーラー
Research Abstract	The physical properties and biocompatibilities of new root fillings, CPO and CPE,composed of tetracalcium phosphate (4CP) powder with either oleic acid or eugenol, respectively, were examined. The former was investigated by measuring the pH change and six variables-that is, flow, working time, setting time, film thickness, solubility and disintegration, radioopacity-according to ISO standards, and the latter was examined histopathologically and radiographically in 12 dogs. The root canals of 14 teeth per dog were filled with CPO, CPE or zinc oxide-eugenol (ZOE) and the periapical tissue reactions were evaluated 1,4,8,12 weeks after fillings. Physical propery These cements fullfilled ISO requirements and showed that these cements have physical properties that are as favorable for root canal sealers as the properties of commercially available zinc oxide eugenol sealer (ZOE) used as a control. Especially, solubilities and distintegration were 0.5-0.7, lower than those of other root canal sealers containing 4CP,which were reported previously. The measured pH values of the cements showed changes to the alkaline range though they, like ZOE,showed a neutral range immediately after mixing. Biocompatibility Hard tissue formation was observed around CPO and CPE.Furthermore, the periapical tissue exposed to CPO revealed slight or moderate inflammation throughout the experimental periods, while severe inflammation was found in the periapical tissue around CPE. These results suggest that CPO may be useful as a root canal filling.