1996 Fiscal Year Final Research Report Summary
Studies on the veneered titanium crown with resin composites for a clinical use
| Project/Area Number |
07672121
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
補綴理工系歯学
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| Research Institution | Showa University |
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Principal Investigator |
FUJISHIMA Akihiro Showa Univ.School of Dentistry, Assistant Prof., 歯学部, 講師 (50209045)
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| Co-Investigator(Kenkyū-buntansha) |
FUKUNAGA Hideki Showa Univ.School of Dentistry, Assistant Prof., 歯学部, 講師 (50199254)
TAMAKI Yukimichi Showa Univ.School of Dentistry, Associate Prof., 歯学部, 助教授 (80197566)
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| Project Period (FY) |
1995 – 1996
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| Keywords | Titanium / Veneered crown with resin composite / Titanium casting / Sandblasting / Alumina / Bond strength / Non-retention beads method |
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| Research Abstract |
The structure of retention beads prepared on the wax pattern was successufully reconstructed on the titanium castings by a centrifugal casing method. However, SEM observation indicated that investment material still remained on the surface of the castings among the retention beads even after sandblasting. Therefore, we aimed to apply a non-retention beads method on the metal frame for veneered titanium crowns.
We at first examined the treating conditions for sandblasting using three average particle sizes of alumina on the plates of cp titanium (cp Ti) and cobalt-chrome allowy (Co-Cr) as a control. EDX analyzes showed the amount of alumina on the surface was 33-45 wt% on cp Ti and 22-42wt% on Co-Cr, respectively. These results suggested that the lower pressure and shorter treating time were suitable to perform sandblasting for titanium than for other dental alloys.
Furthermore, we need more information on the bonding surface of both metal and alumina plates to clarify the bonding mechanism of the surface of the metal sandblasted by alumina particles. We examined bonding strengths of commercial resin bonding systems to cp titanium with sandblasting using three different sizes of alumina particles (50mum, 110mum and 250mum). Sandblasting with 250mum alumina particles showed the highest bonding strength. The bonding strength increased with the increase of the size of alumina particles. However, there were no statistically significant differences among the strength from 110mum and 250mum, and polished surface with 50mum. Bonding strength for sintered alumina plates was significantly lower than that of titanium on the commercial NMC and CSD bonding systems that had excellent bonding for titanium.
I suggest that the existence of alumina on titanium surface by sandblasting with alumina particles was not useful to improve bonding properties of resin composites on the sandblasted surface of cp titanium.
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