Objective: to evaluate the effect of SDF on shear bond strength of LCRMGIC to sound dentine and demineralized dentine.

Materials and Methods: The 40 samples were divided into two main groups (20 teeth for each) according to SDF treatment, Each main group was subdivided into two subgroups according to artificial demineralization. The occlusal enamel was removed using wheel diamond stone under coolant. Samples were wet ground against 600,800,1200 grit SC paper to obtain smooth occlusal surface then molded into self-cured acrylic resin. Half of the samples were immersed into demineralizing solution to obtain dentine surface demineralization, then divided into 4 groups (n = 10), Group 1: Sound Dentine without SDF, Group 2: Sound Dentine with SDF, Group 3: Demineralized Dentine without SDF, Group 4: Demineralized Dentine with SDF. Macroshear bond strength was measured using Universal testing machine.

Results: Results revealed that Demineralized dentine had a significantly higher macroshear bond strength value than sound dentine. Results of first two groups showed that the highest value was found in Group 2 (SDF), followed by Group 1 (no surface treatment) and there was no significant difference between Group 1 and 2 (p=0.106). Results of second two groups showed that the highest value was found Group 4 (SDF), followed by Group 3 (no surface treatment) and there was no significant difference between Group 3 and 4 (p>0.05).

Conclusion: Treatment of sound dentin surface by SDF does not affect bonding to LCRMGIC. Treatment of demineralized dentin with SDF does not affect bond strength to LCRMGIC.