Effect of Colloidal Platinum Nanoparticles on bonding to root dentin

Objectives: Colloidal Platinum Nanoparticles (CPN) is a useful primer solution for bonding to coronal dentin. The purpose of this study was to investigate the effect of CPN on the bond strength of root dentin using 4-META/MMA-TBB resin.

Materials and Methods: Root of extracted human molar according to the ethic committee in Hokkaido University was ground flat perpendicular to the tooth axis and flat surface was created using #600 SiC under running water. Control Group: the dentin surfaces were treated with 10-3 solution followed by rinsing water, and an acrylic rod was bonded with hand mixed 4META/MMA-TBB resin (Sun Medical,Co.). Etch-Pt group: the dentin surfaces were treated with 10-3 solution, followed by applying CPN (0.5mmol/l or 0.1mmol/l. Apt.,LTD.) as a primer solution for 60 seconds and rinsed with water for 20 seconds, and then, an acrylic rod was bonded . Pt-Etch group, dentin surfaces were treated with CPN (0.5mmol/l or 0.1mmol/l) for 60 seconds, and rinsed with water for 20 seconds, followed by applying 10-3 solution, and then, an acrylic rod was bonded. After storage in 37 Celsius degree water, they were sectioned into beams (cross-sectional area 1mm²) for micro tensile bond strength testing at a crosshead speed of 1mm/min.The data was analyzed by Games-Howell method. (p<0.05: n=15).

Results: Figure shows the micro tensile bond strength of 5 experimental groups. There were no statistically significant differences among groups tested.

Conclusion: When applying CPN to root dentin, we obtained about the same bond strength compared to control. The result of this study demonstrated using CPN did not show adverse effects on bond strength to root dentin using 4-META/MMA-TBB resin.