도재 전용액이 지르코니아 코어-도재 비니어의 전단결합강도에 미치는 영향

Abstract

Purpose: This study is to evaluate the effect of modeling liquid on the shear-bond strength between zirconia core and veneering ceramic. Methods: Disk-shaped (diameter: 12.0mm; height: 3.0mm) zirconia were randomly divided into six groups according to the surface conditioning method and whether modeling liquid is used or not to be applied (N=60, n=10 per group): group 1-control group with distilled water(ZD); group 2-control group with modeling liquid(ZM); group 3-airborne particle abrasion with <TEX>$110-{\mu}m$</TEX> <TEX>$Al_2O_3$</TEX>(AD) with distilled water; group 4-airborne particle abrasion with <TEX>$110-{\mu}m$</TEX> <TEX>$Al_2O_3$</TEX> with modeling liquid(AM); group 5-liner with distilled water(LD); group <TEX>$6{\pounds}{\neq}liner$</TEX> with modeling liquid(LM). Contact angles were determined by the sessile drop method at room temperature using a contact angle measurement apparatus. The specimens were prepared using dentin veneering ceramics, veneered, 3mm high and 2.8mm in diameter, over the cores. The shear bond strength test was performed in a Shear bond test machine. Load was applied at a cross-head speed of 0.50mm/min until failure. The fractured zirconia surfaces were evaluated by using stereomicroscope (<TEX>${\times}30$</TEX>). Collected data were analyzed using SPSS(Statistical Package for Social Sciences) Win 12.0 statistics program. Results: ZD showed the highest contact angle(<TEX>$50.6{\pm}5.4^{\circ}$</TEX>) and LD showed the lowest value(<TEX>$6.7{\pm}1.3^{\circ}$</TEX>). Control groups and zirconia liner groups were significantly higher contact angle than liner groups(p<0.05). LD was the highest shear bond strength(<TEX>$43.9{\pm}3.8MPa$</TEX>) and ZD was the lowest shear bond strength(<TEX>$24.8{\pm}4.9MPa$</TEX>). Shear bond strengths of control groups and contact angle of liner groups were not significantly different((p>0.05). Liner groups presented adhesive failures. The others groups showed cohesive and adhesive failures. Conclusion: Modeling liquid groups showed lower contact angles and lower shear bond strength compared to those of distilled water groups.