Bond Strength of Artificially Aged Fiber Reinforced Composite Material. (An in-vitro study)

Aim: The aim of this study was to investigate the effect of time and surface treatments on shear bond strength of repaired fiber reinforced composite to nano-hybrid composite material. Materials and methods: Eighty specimens were prepared of ever-X Posterior (GC Europe). They were equally divided into two groups according to time of repair (after 24 hours and one month). Then, each group subdivided to five subgroups according to surface treatment (1-No surface treatment, 2-Diamond coated bur, two step self-etch adhesive, 3-Diamond coated bur, two step self-etch adhesive, silane, 4-Air abrasion, two step self-etch adhesive, 5-Air abrasion, two step self-etch adhesive, silane). A nano-hybrid composite was added as a material of repair in 2 mm thickness. All groups were thermocycled for 5000 cycles. The two-way ANOVA test was employed for statistical analysis of the data. Results: both the surface treatments and the time of repair had significant effect on SBS of repaired composite. The highest results were achieved in subgroup (Air abrasion and bonding agent) when repaired after one month. Conclusion: One month time relapse has no drastic effect on repair strength of FRC material. Air abrasion is considered a powerful mechanical surface treatment for achieving a highly significant repair strength of FRC material.