title: The effect of various sandblasting conditions on surface changes of dental zirconia and shear bond strength between zirconia core and indirect composite resin.
abstract: OBJECTIVE
  To measure the surface loss of dental restorative zirconia and the short-term bond strength between an indirect composite resin (ICR) and zirconia ceramic after various sandblasting processes.
  
  
  METHODS
  Three hundred zirconia bars were randomly divided into 25 groups according to the type of sandblasting performed with pressures of 0.1, 0.2, 0.4 and 0.6 MPa, sandblasting times of 7, 14 and 21 seconds, and alumina powder sizes of 50 and 110 µm. The control group did not receive sandblasting. The volume loss and height loss on zirconia surface after sandblasting and the shear bond strength (SBS) between the sandblasted zirconia and ICR after 24-h immersion were measured for each group using multivariate analysis of variance (ANOVA) and Least Significance Difference (LSD) test (α=.05). After sandblasting, the failure modes of the ICR/zirconia surfaces were observed using scanning electron microscopy.
  
  
  RESULTS
  The volume loss and height loss were increased with higher sandblasting pressure and longer sandblasting treatment, but they decreased with larger powder size. SBS was significantly increased by increasing the sandblasting time from 7 seconds to 14 seconds and from 14 seconds to 21 seconds, as well as increasing the size of alumina powder from 50 µm to 110 µm. SBS was significantly increased from 0.1 MPa to 0.2 MPa according to the size of alumina powder. However, the SBSs were not significantly different with the sandblasting pressure of 0.2, 0.4 and 0.6 MPa. The possibilities of the combination of both adhesive failure and cohesive failure within the ICR were higher with the increases in bonding strength.
  
  
  CONCLUSIONS
  Based on the findings of this study, sandblasting with alumina particles at 0.2 MPa, 21 seconds and the powder size of 110 µm is recommended for dental applications to improve the bonding between zirconia core and ICR.
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, P. R. China. ; Department of Prosthodontics, West China School of Stomatology, Sichuan University, Chengdu, P. R. China.
authors.forename: Naichuan
authors.initials: N
authors.lastname: Su
authors.affiliation: Department of Dental Technology, West China Hospital of Stomatology, Sichuan University, Chengdu, P. R. China.
authors.forename: Li
authors.initials: L
authors.lastname: Yue
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, P. R. China.
authors.forename: Yunmao
authors.initials: Y
authors.lastname: Liao
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, P. R. China. ; Department of Prosthodontics, West China School of Stomatology, Sichuan University, Chengdu, P. R. China.
authors.forename: Wenjia
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Restorative Dentistry, School of Dentistry, University of Washington, Seattle, USA.
authors.forename: Hai
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Stomatology, Mianyang Central Hospital, Mianyang, P. R. China.
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, P. R. China. ; Department of Prosthodontics, West China School of Stomatology, Sichuan University, Chengdu, P. R. China.
authors.forename: Hang
authors.initials: H
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, P. R. China. ; Department of Prosthodontics, West China School of Stomatology, Sichuan University, Chengdu, P. R. China.
authors.forename: Jiefei
authors.initials: J
authors.lastname: Shen
keywords: All-ceramic; Bond strength; Indirect composite; Sandblasting; Zirconia