ABSTRACT
PURPOSE: The purpose of the current study was to evaluate the effect of incorporating nanoparticles of silver (NAg) and amorphous calcium phosphate (NACP) into a self-etching primer of a resin cement on the microtensile bond strength of dentin, regarding the proven antibacterial feature of NAg and remineralizing effect of NACP. MATERIALS AND METHODS: Flat, mid-coronal dentin from 20 intact extracted human third molars were prepared for cementation using Panavia F2.0 cement. The teeth were randomly divided into the four test groups (n=5) according to the experimental cement primer composition: cement primer without change (control group), primer with 1% (wt) of NACP, primer with 1% (wt) of physical mixture of NACP+Nag, and primer with 1% (wt) of chemical mixture of NACP+Nag. The resin cement was used according to the manufacturer's instructions. After storage in distilled water at 37℃ for 24 h, the bonded samples were sectioned longitudinally to produce 1.0 × 1.0 mm beams for micro-tensile bond strength testing in a universal testing machine. Failure modes at the dentin-resin interface were observed using a stereomicroscope. The data were analyzed by one-way ANOVA and Tukey's post-hoc tests and the level of significance was set at 0.05. RESULTS: The lowest mean microtensile bond strength was obtained for the NACP group. Tukey's test showed that the bond strength of the control group was significantly higher than those of the other experimental groups, except for group 4 (chemical mixture of NACP and NAg; P=.67). CONCLUSION: Novel chemical incorporation of NAg-NACP into the self-etching primer of resin cement does not compromise the dentin bond strength.
Subject(s)
Humans , Calcium , Cementation , Dentin , Molar, Third , Nanoparticles , Resin Cements , Silver , Tooth , WaterABSTRACT
The aim of this study was to evaluate the effect of chlorhexidine [CHX] application on immediate and two-month bond strength of a filled adhesive system. Forty eight non-carious human third molars without enamel of occlusal surface were randomly divided into two main groups according to CHX application: control and CHX. Each main group was further subdivided into 2 subgroups depending on storage time: immediate or two-month collagenase storage. In CHX groups, 2% CHX was applied for 30 s. Filled adhesive resin [PQ1] was applied on the etched dentin surfaces and cured in all experimental groups. Composite resin [Amelogen] was placed on the dentin surfaces and shear bond strength [SBS] was evaluated immediately and after two-month storage in collagenase solution. Failure modes were determined by stereomicroscope. There was no significant difference in immediate SBS between groups [P>0.05]. After two-month collagenase storage, although SBS was significantly reduced in control group [P<0.05], no significant reduction was observed in CHX group [P>0.05]. SBS in CHX group was significantly higher than the control group [P<0.05]. The use of CHX had no adverse effect on immediate bond strength of filled adhesive and could preserve the bond strength