Masanao Inokoshi1, Haruki Shimizu2, Kosuke Nozaki3, Tomohiro Takagaki4, Kumiko Yoshihara5, Noriyuki Nagaoka6, Fei Zhang7, Jozef Vleugels8, Bart Van Meerbeek9, Shunsuke Minakuchi2. 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.
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.
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.
Authors: Markus Wertz; Michael Benno Schmidt; Hieronymus Hoelzig; Maximilian Wagner; Bernd Abel; Gert Kloess; Sebastian Hahnel; Andreas Koenig Journal: Materials (Basel) Date: 2022-06-24 Impact factor: 3.748