| Project/Area Number |
61480398
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Conservative dentistry
|
|---|
| Research Institution | Tokushima University |
|---|
Principal Investigator |
YOSHIYAMA Masahiro (1988) Research Assistant, Dept. of Operative Dentistry, Tokushima Univ. School of Dentistry, 歯学部, 助手 (10201071)
内田 昭次 (1986-1987) 徳島大学, 歯学部, 教授 (90112060)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
YAMAMOTO Reiko Research Assistant, Dept. of Operative Dentistry, Tokushima Univ. School of Dent, 歯学部附属病院, 助手 (20200850)
ISHIKAWA Yasuko Lecturer, Dept. of Pharmacology,Tokushima Univ. School of Dentistry, 歯学部, 講師 (40144985)
ISHIDA Hajime Professor, Dept. of Pharmacology, Tokushima Univ. School of Dentistry, 歯学部, 教授 (70028364)
宇野 義治 徳島大学, 歯学部, 助手 (60183208)
井上 尚也 徳島大学, 歯学部, 助手 (00183187)
高橋 良明 徳島大学, 歯学部附属病院, 助手 (20175433)
長谷川 清 徳島大学, 歯学部附属病院, 助手 (20172885)
|
|---|
| Project Period (FY) |
1986 – 1988
|
| Project Status |
Completed (Fiscal Year 1988)
|
| Budget Amount *help |
¥7,200,000 (Direct Cost: ¥7,200,000)
Fiscal Year 1988: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1987: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1986: ¥5,700,000 (Direct Cost: ¥5,700,000)
|
|---|
| Keywords | Dentin / Dentin Hypersensitivity / Non-collagenous protein / Ca-binding ability / Osteonectin / Phosphophoryn / 管状膜様構造物 |
|---|
| Research Abstract |
In this investigation, we have studied the ultrastructural changes of dentinal tubules and tubular membranes in hypersensitive area in exposed human dentin, the purification of noncollagenous proteins from tubular membranes, and their characteristics.
The results obtained from the biopsy of hypersensitive teeth showed the opening of dentinal tubules and the appearance of tubular membranes in the hypersensitive area of exposed dentin.
On the other hand, dentinal tubules were occluded with superfine or rhombohedral crystals in naturally desensitized area on the same dentin surface and the mineralization of the dentinal tubules was obseved in the area.
These results suggested that the appearance of tubular membranes may be closely involved in occurance of dentin hypersensitivity through the control of remineralization of dentinal tubules.
Extraction and separation of noncollagenous proteins from tubular mem-branes were carried out to investigate the physiological function of tubular membranes. An osteonectin was purified from the noncollagenous proteins. We also purified osteonectin from human dentin powder. It was shown that dentin osteonectin was highly phosphorylated sialoprotein more than other hard con-nective tissues and the molecular weight of it was 23K daltons. Moreover, dentin osteonectin was able to bind calcium ions strongly and selectively.
In conclusion, the presence of dentin osteonectin in tubular membranes suggested that tubular membranes were closely related to the occurance of dentin hypersensitivity, and that dentin osteonectin may play important roles on the re-calcification of the dentinal tubules through the transportation of calcium ions.
|
