| Project/Area Number |
10671860
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Surgical dentistry
|
|---|
| Research Institution | Tohoku University |
|---|
Principal Investigator |
KATOU Fuminori Tohoku University Dental Hospital Lecturer, 歯学部・附属病院, 講師 (60204492)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
OHTANI Haryo Tohoku University School of Medicine Associate Professor, 大学院・医学研究科, 助教授 (30133987)
|
|---|
| Project Period (FY) |
1998 – 1999
|
| Project Status |
Completed (Fiscal Year 1999)
|
| Budget Amount *help |
¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1999: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1998: ¥1,000,000 (Direct Cost: ¥1,000,000)
|
|---|
| Keywords | Foreign body reaction / Skin Flap / Titanium / Matrix metalloproteinase / B7-2 / Tissue inhibitor of matrix metalloroteinase / Langerhans cell |
|---|
| Research Abstract |
Titanium implant has been widely used for the reconstruction surgery of oral cancer and for the osteosynthesis of mandibular fracture.
The fibrogenic tissue surrounding the implants consists of activated fibroblasts and is remodeled throughout. Tissue remodeling is made up of the balance between synthesis and decomposition of extracellular matrix. Expression of matrix metalloproteinases (MMP) and tissue inhibitors of matrix metalloproteinase (TIMP) in the spindle-shaped cells (fibroblasts or macrophages), vascular endothelial cells and smooth muscle cells within the fibrogenic tissue was as follows. MMP-1, MMP-3, MMP-8 and MMP-9 were negative. TIMP-2 was strongly positive. By contrast, fibroblasts within the scar tissue expressed neither MMPs nor TIMPs.
Furthermore, we investigated the inflammatory response of skin flaps surrounding the encapsulation tissue of titanium implant. Prominent inflammatory changes were observed in most cases. Skin flaps showing inflammatory changes were infected by Candida albicans. Infiltrating leukocytes to the dermis were memory-type T lymphocytes expressing CD4/CD45RO. These lymphocytes were clustered with Langerhans cells (CD la+). Langerhans cells in the dermis were B7-2+/CD-83+, and intimately touched to the memory -type T lymphocytes. Ki-67 labeling index of CD4+ T lymphocytes was higher than that of CD8+ T lymphocytes. Numerous mature Langerhans cells were observed in the lymphatic vessels. These Langerhans cells were B7-2+/B7-1+/CD83+. These results suggest that Langerhans cells play an important roles in the encapsulation process against titanium implant.
|
