OBJECTIVE: To develop a bonding agent (primer) for reliable and durable adhesion with Zirconia. METHODS: The durability of adhesion to zirconia by experimental primer (B-EXP) (Bisco), and the commercially available zirconia-bonding agents, i.e. Metal/Zirconia Primer (IV-MZP) (Ivoclar Vivadent) and Clearfil Ceramic Primer (K-CCP) (Kuraray) was evaluated. The zirconia (Cercon Type) was sandblasted by aluminum (50 µm), then cleaned by DI water and dried. Then zirconia surface was applied primers according to manufacturing instructions. Duolink (Bisco), Panavia F2.0 (manufac turer recommended, Kuraray), or Multilink Automix (manufacturer recommended, Ivoclar Vivadent) was placed into a #5 gel cap (area 0.1684 cm2), and light-cured for 20 seconds in each side (4 sides totally). Cured specimens were stored (2 hours/37 ºC or 4 hours/100 ºC vigorous aging) in DI water and tested shear bond strength using a universal tester (Instron 4466) at a speed of 5 mm/min. RESULTS:
Shear Bond Strength, MPa (SD), n = 8~9
Primer | B-EXP | K-CCP | IV-MZP |
Cement | Duolink | Panavia F2.0 | Multilink |
2 hours/37 ºC | 14.97 (1.47)a | 7.19 (0.97)b | 5.19 (2.03)c |
4 hours/100 ºC | 14.11 (1.50)a | 6.95 (0.83)b | 1.36 (1.88)d |
Using a t-test, shear bond strengths of B-EXP are significantly higher than K-CCP and IV-MZP, either before and after vigorous aging (p < 0.01). Shear bond strength of B-EXP and K-CCP didn't significantly decrease after vigorous aging (p > 0.05), while the strength of IV-MZP significantly decreased (p < 0.01). CONCLUSION: The experimental bonding agent not only has significantly stronger bonding ability to zirconia than such type of products in the market, but also has more reliable and durable bonding strength.