Crystallographic and morphological analysis of sandblasted highly translucent dental zirconia

Masanao Inokoshi; Haruki Shimizu; Kosuke Nozaki; Tomohiro Takagaki; Kumiko Yoshihara; Noriyuki Nagaoka; Fei Zhang; Jozef Vleugels; Bart Van Meerbeek; Shunsuke Minakuchi

doi:10.1016/j.dental.2017.12.008

Crystallographic and morphological analysis of sandblasted highly translucent dental zirconia

Dent Mater. 2018 Mar;34(3):508-518. doi: 10.1016/j.dental.2017.12.008. Epub 2018 Jan 8.

Authors

Affiliations

¹ Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Japan. Electronic address: m.inokoshi.gerd@tmd.ac.jp.
² Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Japan.
³ Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Japan.
⁴ Department of Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Japan.
⁵ Center for Innovative Clinical Medicine, Okayama University Hospital, Japan.
⁶ Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School, Japan.
⁷ KU Leuven (University of Leuven), Department of Materials Engineering, Belgium; KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & University Hospitals Leuven, Dentistry, Belgium.
⁸ KU Leuven (University of Leuven), Department of Materials Engineering, Belgium.
⁹ KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & University Hospitals Leuven, Dentistry, Belgium.

PMID: 29325861
DOI: 10.1016/j.dental.2017.12.008

Abstract

Objective: To assess the influence of alumina sandblasting on four highly translucent dental zirconia grades.

Methods: Fully sintered zirconia disk-shaped specimens (15-mm diameter; 0.5-mm thickness) of four highly translucent yttria partially stabilized zirconia (Y-PSZ) grades (KATANA HT, KATANA STML, KATANA UTML, Kuraray Noritake; Zpex Smile, Tosoh) were sandblasted with 50-μm alumina (Al₂O₃) sand (Kulzer) or left 'as-sintered' (control) (n=5). For each zirconia grade, the translucency was measured using a colorimeter. Surface roughness was assessed using 3D confocal laser microscopy, upon which the zirconia grades were statistically compared for surface roughness using a Kruskal-Wallis test (n=10). X-ray diffraction (XRD) with Rietveld analysis was used to assess the zirconia-phase composition. Micro-Raman spectroscopy was used to assess the potentially induced residual stress.

Results: The translucency of KATANA UTML was the highest (36.7±1.8), whereas that of KATANA HT was the lowest (29.5±0.9). The 'Al₂O₃-sandblasted' and 'as-sintered' zirconia revealed comparable surface-roughness Sa values. Regarding zirconia-phase composition, XRD with Rietveld analysis revealed that the 'as-sintered' KATANA UTML contained the highest amount of cubic zirconia (c-ZrO₂) phase (71wt%), while KATANA HT had the lowest amount of c-ZrO₂ phase (41wt%). KATANA STML and Zpex Smile had a comparable zirconia-phase composition (60wt% c-ZrO₂ phase). After Al₂O₃-sandblasting, a significant amount (over 25wt%) of rhombohedral zirconia (r-ZrO₂) phase was detected for all highly translucent zirconia grades.

Significance: Al₂O₃-sandblasting did not affect the surface roughness of the three highly translucent Y-PSZ zirconia grades, but it changed its phase composition.

Keywords: Alumina sandblasting; Micro-Raman; Stress; XRD; Zirconia.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aluminum Oxide / chemistry
Colorimetry / methods
Crystallography / methods*
Dental Etching / methods
Dental Materials / chemistry*
Dental Stress Analysis
Materials Testing
Spectrum Analysis, Raman
Surface Properties
Zirconium / chemistry*

Substances

Dental Materials
Zirconium
Aluminum Oxide
zirconium oxide