Two-kinds of Colloidal-Platinum-Nanoparticles improve the resin/dentin bond-strength using 4-META/MMA-TBB
Objectives: Our previous studies showed that pre-treatments of dentin surface with Colloidal Platinum Nanoparticles (CPN, APt Co.) which have sodium citrate as a protective agent improved the bond strength between 4-META/MMA-TBB resin (SuperBond, SUNMEDICAL Co.) and dentin at 3rd IAD 2008 and 87th IADR 2009. There is another kind of CPN which uses sodium polyacrylate as a protective reagent. The purpose of this study was to compare the effects of CPN with sodium citrate (CPN-C) and CPN with sodium polyacrylate (CPN-P) on resin-dentin bond strength using SuperBond.
Materials and Methods: Nine intact extracted human third molars according to the ethic committee of Hokkaido University's regulations were cut perpendicularly to a tooth axis and ground by #600 silicon carbide paper to expose dentin surfaces. They were randomly divided into 3 groups; Control, Etch-CPN-C, Etch-CPN-P. After etching with 10 % citric acid and 3 % ferric chlorite solution as manufacture's instruction, CPN-C or CPN-P were applied for 1 min and washed with distilled water and dried by gentle air. Then we applied SuperBond using the brush-on-technique and placed PMMA blocks on top and waited for 6 min. After one day in 37 Celsius degree water, specimens were cut into sticks and exposed to the micro-tensile bond strength test. The data was analyzed by One-way ANOVA and Tukey test (p<0.05).
Results: The bond strength of Etch-CPN-C was 29.4 MPa (SD: 10.7, n=24), Etch-CPN-P was 38.8 MPa (SD: 11.7, n=26) and Control was 17.2 MPa (SD: 8.0, n=27). The bond strength of Etch-CPN-C and Etch-CPN-P were significantly higher than the Control. Interestingly the bond strength of Etch-CPN-P was statistically higher than Etch-CPN-C.
Conclusion: Both CPN-C and CPN-P raised the bond strength between 4-META/MMA-TBB resin and dentin. CPN-P improved the bond strength more than CPN-C.
