2013 Fiscal Year Final Research Report

Nondestructive Analysis of Tooth - Adhesive Interfaces by Surface Sensitive XAFS.

Research Project

Project/Area Number	24890061
Research Category	Grant-in-Aid for Research Activity Start-up
Allocation Type	Single-year Grants
Research Field	Dental engineering/Regenerative dentistry
Research Institution	Tokyo Medical and Dental University
Principal Investigator	WADA Takahiro 東京医科歯科大学, 医歯(薬)学総合研究科, 助教 (10632317)
Project Period (FY)	2012-08-31 – 2014-03-31
Keywords	歯科材料 / XAFS / 表面・界面分析 / X線光電子分光 / 歯学
Research Abstract	Dental adhesives are used to bond the dental materials to teeth. To obtain high durability and adhesive strength, informations about the tooth (enamel/dentin) - adhesive interface are extremely important. However, conventional analysis methods have some limitations, such as destructive. X-ray absorption fine structure (XAFS), which is one of spectroscopic methods, makes possible to estimate the various properties (electronic state, peripheral atoms, coordination numbers and the bond distance) of a particular atom in the substance. In this study, we analyze the chemical state of Ca in hydroxyapatite (HAp)-10-methacryloyloxydecyl dihydrogen phosphate (MDP) mixture. MDP is widely used as an adhesive monomer.Surface sensitive XAFS techniques are applied for the HAp/MDP interface analysis. As results, we found that HAp - 10-MDP interface is thin MDP-Ca layer ( < 100 nm), and its depth of layer is depend on treatment condition (the ratio of HAp and MDP solution and the treatment period).