Evaluation of Ceramic-resin Bonding Using Two Specimen Bonding Substrates

Abstract

Objective: The objective of this study was to compare two bonding models and two surface treatments on the lithium disilicate ceramics with two resin cements using a microtensile bond test (µTBS). Method: Ceramic blocks (e.max CAD®, Ivoclar) were sectioned, polished and fired for final crystallization. They were treated with two surface treatments: (1) hydrofluoric acid (HF) (IPS Ceramic Etching gel) etched followed by silane (Monobond-S, Ivoclar) application; (2) HF etched, silane applied, followed by hot air drying, rinsing with hot water, dried and unfilled resin (Heliobond, Ivoclar) applied. Ceramic blocks without surface treatment were control groups. Two bonding substrates were used: resin composite (Estenia, Kuraray-Noritake) and ceramic. The bonded substrates were divided into two bonding models: ceramic to ceramic (C-C) and ceramic to resin composite (C-R). Two resin cements, Variolink II® (Ivoclar) and Clearfil SA Cement (Kuraray-Noritake), were tested. Each group was sectioned into beams (n=30) and stored in distilled water for 7 days at 37°C. Specimens were subjected to µTBS. Failure modes were determined with light microscopy and SEM. ANOVA and Bonferroni tests were used for statistical analysis (p<0.05). Result: All control groups spontaneously debonded during cutting. The C-C groups showed significantly higher µTBS than C-R groups (p<0.05). Failure mode in C-R groups was dominated by cohesive failure in resin cement while in C-C groups was mostly mixed failure. Ceramic treated with HF etching and silanization and cemented with Variolink II showed the highest µTBS (53.5±6.6MPa) while ceramic treated with HF etching, silanization, hot air and water treatment and cemented with Clearfil SA Cement showed the lowest µTBS (35.4±7.0MPa) in the C-C groups. Conclusion: C-C model is recommended for evaluating the µTBS of ceramic-resin cement adhesion. Variolink II showed better bonding than Clearfil SA Cement.