摘要
Abstract
Objective: To investigate the effects of 3 surface different treatments on the crystal structure,shear bond strength, roughness value and flexural strength of zirconia. Methods: The zirconia specimens were prepared and randomly divided into 4 groups and received the following treatments: (1) blank control group,the specimens without treatments; (2)sandblasting with alumina group,sandblasting the specimens with 110 μm alumina particles for 21 s as working pressure 0. 25 MPa and working distance 10 mm; (3) laser etching group, coating the surface of the specimens with graphite powder and using Er: Yttrium Aluminum Garnet (Er: YAG) laser to irradiate the surface 30 s; (4) hot-etching group, putting the specimens in a closed reactor within a 1: 1 mixture of 40％ (mass traction) nitric acid and 68％ (mass traction) hydrofluoric acid liquid, the reaction of 30 min in a water bath at 100 degrees centigrade. The changes of crystal structure, shear bond strength(SBS) and flexural strength of zirconia after different surface treatments were tested. Results: The X-ray diffractometer (XRD) patterns showed that the volume percentage of monoclinic phase of the 4 groups was 0.91％, 12.50％,6.64％ and 17.81％ respectively. The roughness value for the four groups were as follows: blank control group, (0. 29 ± 0.01) μm; sandblasting with alumina group, (1.05 ±0.11) μm; laser etching group, (0. 73 ±0.04) μm; hot-etching group, (1.31 ±0.06) μm,respectively (P< 0. 05). Mean SBS was (7. 09 ±0. 46) MPa in blank control group, (12.14 ± 1. 51) MPa in sandblasting with alumina group, (8. 82 ±0. 74) MPa in laser etching group and (11. 97 ± 0.99) MPa in hot-etching group. There was no statistically significant difference between sandblasting with alumina group and hot-etching group (P>0. 05), but the difference between the other groups were statistically significant (P <0. 05). Mean three-point bending was (933.70 ±44.13) MPa in blank control group, (850.95 ± 60.66) MPa in sandblasting with alumina group, (771. 53 ±68. 08) MPa in laser etching group and (766. 27 ± 57. 49) MPa in hot-etching group. There was no statistically significant difference between sandblasting with alumina group and hot-etching group (P>0. 05),but the difference between the other groups were statistically significant(P< 0. 05). Conclusion: After different surface treatments, the surface of zirconia has changed from tetragonal to monoclinic phases in varying degrees. In addition, surface treatments could improve the bond strength of zirconia to resin cement, and also lead to a decrease in the flexural strength of zirconia.关键词
氧化锆/喷砂/热酸蚀Key words
Zirconia/Sandblasted/Hot-etching分类
医药卫生
