2006 Fiscal Year Final Research Report Summary
Studies on Secondary Caries Initiation Mechanism and Finding Prevention Methods Using a Newly Modified Oral Biofilm Reactor
| Project/Area Number |
16390544
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Conservative dentistry
|
|---|
| Research Institution | Tokyo Medical and Dental University |
|---|
Principal Investigator |
MATIN Khairul Tokyo Medical and Dental University, COE Research Associate Graduate School, Professor Junior (00372433)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
TAGAMI Junji Tokyo Medical and Dental University, Graduate School, Professor (50171567)
HANADA Nobuhiro National Institute of Public Health, Department of Oral Health, Director (70180916)
KITASAKO Yuichi Tokyo Medical and Dental University, Graduate School, Assistant Professor (30361702)
|
|---|
| Project Period (FY) |
2004 – 2006
|
| Keywords | Primary caries / Secondary caries / Cariogenic Bacteria / Oral Biofflm Reactor (QBE) / Arifieial biofilm / Self-surface-cleaning / Glucan / 2-DE |
|---|
| Research Abstract |
Newly modified computer software (EPC-2000) operated artificial mouth system (AMS) was developed and renamed as oral biofilm reactor (OBR). Automatic delivery of bacterial suspensions and mediums on to specimens became possible by controlling the flow rate in accordance of the need of a particular study simulating the human oral environments.
Biofilm induced caries models, namely; 1) Primary caries model or White Spot Enamel Lesion (WSEL) and 2) Secondary caries model were established using bovine and human extracted teeth. Visible WSELs were examined by Quantitative light-induced fluorescence (QLF), scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDS) and nanoindentor. Results indicated that demineralization occurred on the enamel surfaces. The lesion depth increased time dependently that showed co-relationship with Ca and P mineral loss and loss of nano-hardeness and elasticity. The artificial secondary caries induced by multi-species cariogenic bacteria at the interface of composite restoration showed wide gap-formation when bonding material was not used. Quantitative genomic DNA analysis (Real-time PCR) confirmed invasion of bacteria in the demineralized lesion and lesions were non-invasively indentified by Micro-CT.
Newly developed dental materials (including adhesives, fluoride oligomer incorporated coating, Teflon incorporated restoratives) were investigated for their self-surface-cleaning capability and biofilm inhibition. Also, alkali-ion water (AW) found to be effective in dissolving glucan polymers of the biofilms. Real-time PCR and 2-DE showed variations on DNA quantification and protein expression after AW or ozone treatment.
|
