Influence of surface treatment on microtensile bond strength of self-adhesive resin cement to zirconia

ABSTRACT

Different alternative surface treatments, which have not been fully investigated, have been suggested to improve bonding to zirconia. The aim of this study was to compare microtensile bond strength of self-adhesive resin luting cements to zirconia following different surface treatments., Three blocks of zirconia [Cercon, Degussa, Germany] and three composite blocks [Z100, 3M, ESPE, USA] with 11x11x5 mm dimension were made. The blocks were divided into three groups. The ceramic blocks were cemented to the composite blocks using G-Cem [GC, Japan] according to the manufacturer's specifications. All samples were stored in 37°C distilled water for 24 hours and later sectioned in two axes using diamond disk to obtain bar shape specimens with a cross-sectional area of approximately 1mm[2] and 10mm long [n=12]. Specimens were stored in 37°C distilled water for 72 hours and thermocycled for 2000 cycles [5°C/55°C]. Each specimen was then attached to a microtensile test device. Bond strength was measured with crosshead speed of Imm/min. Failure modes were examined under stereomicroscope [x40]. Representative specimens were observed by scanning electron microscopy [SEM]. Bond strength data were analyzed with one way ANOVA and Tukey tests [a-0.05]. Alloy Primer subgroup [49.64 +/- 7.02] had a significantly higher bond strength than silane [42.12 +/- 4.2] and silicoating with silanopen [21.78 +/- 4.7] [p<0.0001]. Silanopen had the lowest bond strength in this group. SEM observation indicate that ceramic surface in silanopen group had fewer irregularities. Primers containing MDP functional monomer like Alloy Primer affect the durability of self adhesive resin cement [G-Cem] bond strength to zirconia