New quantitative and qualitative evaluations on tooth mineral changes after de-and remineralization
Grant-in-Aid for General Scientific Research (C)
|Allocation Type||Single-year Grants|
|Research Institution||Nagasaki University|
KAWASAKI Koji(1991, 1993) Nagasaki University, School of Dentistry, Lecturer, 歯学部, 講師 (60161303)
稲葉 大輔(1992) 長崎大学, 歯学部, 講師 (90146085)
TAKAGI Okiuji Nagasaki University, School of Dentistry, Professor, 歯学部, 教授 (80005090)
TAGUCHI Nobuhiro Nagasaki University, School of Dentistry, Assistant Professor, 歯学部, 助手 (20216831)
INABA Daisuke Nagasaki University, School of Dentistry, Lecturer, 歯学部, 講師 (90146085)
|Project Period (FY)
1991 – 1993
Completed(Fiscal Year 1993)
|Budget Amount *help
¥2,100,000 (Direct Cost : ¥2,100,000)
Fiscal Year 1993 : ¥300,000 (Direct Cost : ¥300,000)
Fiscal Year 1992 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1991 : ¥1,100,000 (Direct Cost : ¥1,100,000)
|Keywords||Enamel / mineral / de-and remineralization / digital subtraction / hydroxyapatite / TCP / high-resolution electron microscopy / 象牙質 / 脱灰 / 再石灰化 / 画像解析 / デジタルサブトラクション / 化学分析 / 歯牙 / ミネラル / サブトラクション|
In order to evaluate tooth mineral changes after de-and remineralization quantitatively, we developed two types of the methods. In addition by means of high-resolution electron microscopy we evaluated the changed mineral qualitatively after demineralization or laser irradiation.
(1)Digital subtraction method
Subtraction image between two digitized microradiograms of the same enamel specimen before and after demineralization made it possible to visualized the changed mineral area by demineralization clearly. We also evaluated the changed mineral quantitatively using regression formula between gray level and alminum thickness.
(2)CCD camera method
We developed quantitative mineral profile evaluation method using CCD camera. The microradiograms of tooth root specimen after de-and remineralization were input as a digital image through CCD camera to a computer. The gray level of each pixel was transposed to the equivalent of alminium thickness according to the regression formula between alminium thickness and its gray level. By means of this method we can show the profile of the mineral vol% in an interested area on the screen simultaneously.
Crystllographic analysis with high-resolution electron microscopy suggested that enamel treated by demineralization andlaser could change from hydroxyapatite to alpha-or beta-TCP(tricalciumphosphate).
Research Products (5results)