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See the full abstract here:
http://ocs.ciemat.es/EPS2019ABS/pdf/P4.3022.pdf
Zirconia shows excellent dental applications such as crowns and bridges. When adhering a zirconia crown to a tooth, the abutment tooth needs to be prepared a large amount and thus the bonding area on the abutment tooth becomes small. For this reason, bond strength is important factor for keeping the application in the oral cavity or abutment tooth. In recent years, low temperature plasma has been attracted as a new surface treatment method in dental field. Effectiveness of low temperature plasma in improving the bond strength of zirconia has been reported[1]. However, effective irradiation conditions and its mechanism have not been clarified. The purpose of this study is to assess the effects of surface treatment by various gas atmospheric low temperature plasma and to find the effective gas species for improving the bond strength on zirconia using multi gas plasma jet.
Zirconia pieces (15 mm x 15 mm x 3 mm) polished with waterproof abrasive paper was used in this study. Atmospheric low temperature plasma generated by N2, CO2, O2, Air and Ar was irradiated from 3 mm above zirconia pieces for 10 s. After plasmatreatment, zirconia pieces and stainless rods were bonded by resin cement. The bonding area was φ3 mm. Next, these samples immersed in water at 37±2°C for 24 h. Untreated group and sandblasting treatment group were used as control.
The bond strength was 9.75 MPain the untreated group, and 18.5 MPa in the sandblast treatment group. In any plasma treatment, the bond strength was increased compared with the control group. Especially, N2 plasma treatment showed high bond strength equivalent to sandblasting treatment. These results indicate the effectiveness of atmospheric low temperature plasma treatment for adhesion improvement of zirconia. In addition, to understand the mechanism the surface of zirconia pieces after plasma treatment was observed using AFM and XPS.
[1] Y. Itoet al., J.Prosthodont Res.,60, 289-93(2016).
