| Project/Area Number |
63570908
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
補綴理工系歯学
|
|---|
| Research Institution | Tokyo Medical and Dental University |
|---|
Principal Investigator |
ISHIHATA Nobuo Tokyo Medical and Dental Univ. Faculty of Dentistry, 歯学部, 手 (70114733)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
OKUNO Osamu Tokyo Medical and Dental Univ. Faculty of Dentistry, 医用機材研究所金属材料部門, 助教授 (50014080)
MIZUTANI Hiroshi Tokyo Medical and Dental Univ. Faculty of Dentistry, 歯学部, 講師 (00014324)
AI Minoru Tokyo Medical and Dental Univ. Faculty of Dentistry, 歯学部, 教授 (00013889)
|
|---|
| Project Period (FY) |
1988 – 1989
|
| Project Status |
Completed (Fiscal Year 1989)
|
| Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1989: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 1988: ¥1,300,000 (Direct Cost: ¥1,300,000)
|
|---|
| Keywords | SmCo_5 magnet / Pt-Co magnet / Magnet attachment / Denture / Handicapped patient / Prosthetically hopeless teeth / サマリウムコバルト合金(SmCo_5)磁石 / サマリウムコバルト磁石 |
|---|
| Research Abstract |
SmCo_5 magnet could be used as magnetic attachment to partial denture retainer for periods of up to several years. But corrosive quality of magnet had been unsolved problem, so clinically the magnet had to be exchanged every time magnetic force was gone from corrosion.
Platinum-Cobalt magnet (Pt-Co magnet) which is inferior to SmCo_5 magnet in magnetic properties is excellent at the corrosion resistance in oral fluids. Therefore Pt-Co magnet was measured whether it could be used as magnetic attachment. The retention of 4Xl.5 mm Pt-Co magnet was 172g by using stainless steel cup type yoke. This retention was rather small as main retainer, but Pt-Co magnetic attachment was proved to be usable as subretainer to prosthetically hopeless teeth-teeth with bone loss or large mobility.
We also examined the removal energy per definite retention of SmCo_5 magnetic attachment and clinically used retainers, so as to elucidate the retentive characteristics of magnetic attachment. The energy of magnetic attachment was the minimum of all of them, which showed that these magnetic attachments could be available for prosthetically hopeless teeth from a fundamental standpoint.
In clinical trial cases these magnetic attachments have been successfully used not only in five dentures of handicapped patients but in more than 20 hopeless teeth.
|
