Consepsis

The specimens were assigned into nine experimental groups (n=10) based on the dentin pretreatments with a 2% CHX solution (Consepsis, Ultradent Inc., South Jordan, UT, USA) or three different NPs (SNPs, TNPs, and ZNPs; purchased from ASEPE Company, Tabriz, Iran). The SNPs, TNPs, and ZNPs had the particle sizes of 20 nm, <50 nm, and 20 nm, respectively.
In group A (control group), a cavity conditioner (Cavity Conditioner, GC Co, Japan) was applied on the prepared dentin surfaces according to the manufacturer’s instructions. 1 mL of a 2% CHX solution was applied on the prepared dentin surfaces using a foam pellet saturated with the solution for 1 minute. Then, the dentin surfaces were blot-dried to remove the excess CHX before applying the conditioner in group B and after applying the conditioner in group F. In groups C, D, and E, the prepared dentin surfaces were pretreated with 1 cc 0.1% SNP, 0.1% TNP, and 0.1% ZNP solutions, respectively, for 1 minute, before applying the conditioner. Then, the dentin surfaces were rinsed thoroughly for 1 minute. SNPs, TNPs, and ZNPs were applied for 1 minute after applying the conditioner in groups G, H, and I, respectively. Then, the dentin surfaces were rinsed thoroughly for 1 minute.

The process of dentin conditioning was performed as described for previous groups. Next, 2% CHX solution (Consepsis; Ultradent Products Inc., South Jordan, UT, USA) was applied
to the prepared surfaces with its applicator for 60 seconds and gently air-dried for 10 seconds according to the manufacturer’s instructions. Afterwards, the RMGIC application
and storage of samples were performed in a similar fashion as in the group I_a. Finally, the samples were thermocycled for 500 cycles.