• Airborne-particle abrasion increased zirconia roughness but not bond strength to porcelain. • Zirconia translucency and yttria content did not affect porcelain bonding. • Porcelain bonding to zirconia was comparable to established metal–ceramic systems. • Co–Cr alloy showed the highest bond strength with dental porcelain. • Microscopy revealed sharp porcelain–zirconia interfaces and yttrium segregation. Porcelain chipping in zirconia-based dental restorations remains a major clinical complication. This study evaluated the effects of airborne-particle abrasion (APA) and yttria content in zirconia on porcelain–zirconia bond strength. Six groups were tested: low-translucency (3Y-TZP) and high-translucency zirconia (4Y-TZP), each with or without APA, and APA-treated Co–Cr and Ti–6Al–4V alloys as metal–ceramic references. Bond strength was assessed using the Schwickerath test. Interfacial structure and mechanical properties were analyzed by scanning and transmission electron microscopy and nanoindentation. APA significantly increased zirconia surface roughness but did not improve bond strength. Zirconia composition had no effect on porcelain bonding. Bond strength values for porcelain-zirconia (34.0–40.6 MPa) were comparable to those of metal–ceramic systems, lower than Co–Cr (45.5 MPa) but similar to Ti–6Al–4V (37.3 MPa). Microscopy and nanoindentation revealed sharp zirconia–porcelain interfaces with pronounced mechanical mismatch and yttrium segregation at grain boundaries.
Antanasova et al. (Fri,) studied this question.