The effect of surface treatment on bond strength of layering porcelain and hybrid composite bonded to zirconium dioxide ceramics.
OBJECTIVE
The purpose of this study was to investigate the differences between Rocatec (as surface treatment) and #600 polishing (as control) on shear bond strength of layering porcelain and hybrid composite to zirconium dioxide ceramics.


METHODS
Manufactured zirconia blocks used in this study were yttrium partially stabilized zirconia (YTZ(®)), and veneering materials were NobelRondo Zirconia Dentin A2 High Value (NZR) and Estenia C&B (ES). Total 48 zirconia blocks were fabricated (10 mm × 10 mm × 20 mm). The blocks of 24 each were treated by Rocatec and #600 paper, respectively. Surface treated zirconia blocks were divided into two groups, according to veneering materials of NZR and ES. NZR was fired and ES was polymerized to zirconia. The fabricated specimen was fixed to mounting jig and applied shear force using the universal testing machine at a crosshead speed of 0.5 mm/min. All results were statistically analyzed by two-way ANOVA and Tukey's test. EPMA analysis and SPM analysis of specimen interface were carried out.


RESULTS
Mean shear bond strength of each condition was: NZR/#600; 23.3 (S.D. ±7.0) MPa, NZR/Rocatec; 26.9 (S.D. ±7.0) MPa, ES/#600; 10.7 (S.D.±2.4) MPa, ES/Rocatec; 12.5 (S.D.±0.8) MPa.


CONCLUSIONS
From the results of this study, shear bond strength of layering porcelain to zirconia was higher than that of restorative hybrid resin. However the more study will be needed, the appropriate choice of materials became the gides to the expansion of the applied cases of metal-free prothesis.
Department of Crown and Bridge, The Nippon Dental University, School of Life Dentistry at Tokyo, 1-9-20 Fujimi, Chiyoda-ku, Tokyo 102-8159, Japan.
Minori
M
Hatta
Akikazu
A
Shinya
Daiichiro
D
Yokoyama
Harunori
H
Gomi
Pekka K
PK
Vallittu
Akiyoshi
A
Shinya
D002516:Ceramics; D001840:Dental Bonding; D003738:Dental Cements; D003764:Dental Materials; D003776:Dental Porcelain; D015040:Zirconium
D003738:Dental Cements; D003764:Dental Materials; C076811:Rocatec; D003776:Dental Porcelain; D015040:Zirconium; C028541:zirconium oxide