The effect of atmospheric plasma treatment of dental zirconia ceramics on the contact angle of water

Abstract

The purpose of this study was to investigate the effect of atmospheric pressure plasma application on the water contact angle (CA) of zirconia ceramics. Two zirconia ceramics (Katana, Kuraray Noritake Dental and Lava, 3 M ESPE) were used to test the plasma treatment (SAP, surface) with argon gas for one minute (1 L/min). To measure the CA, a drop of water was placed on a zirconia surface, which was observed under optical microscopy, and images were used to calculate the CA (n = 5). The dynamic behavior of the surface wettability was analyzed by collecting the CA data over a 70-hour period. CA data were analyzed by two-way ANOVA and the Tukey test (5%). The CA baseline values were 66° and 68° for Katana and Lava, respectively. After the application of plasma, the CA was reduced significantly to 36° and 31°, respectively. The CAs for Lava zirconia and Katana returned to baseline values after 5 and 15 hours, respectively. The plasma treatment improved the wettability of the zirconia surface, decreasing the CA approximately 50%. The duration of the effect of plasma on zirconia surfaces was at least 5 hours and material-dependent.