The mechanism responsible for hydrogen-peroxide- or sodium-hypochlorite-induced reductions in dentin bond strength is unknown. This in vitro study tested the hypothesis that these oxidizing agents were responsible by attempting to reverse the effect with sodium ascorbate, a reducing agent. Human dentin was treated with these oxidants before or after being acid-etched and with or without post-tr...

Sodium ascorbate has recently been suggested to compensate decreased bond strength of composite resin to bleached tooth surfaces. The aim of present study was to evaluate the effect of 10% sodium ascorbate on bleached bovine enamel morphology and microhardness considering the possibility of its effect on enamel surface characteristics. A total of 69 bovine enamel slabs were prepared and mounted...

This study evaluated the effect of restorative protocol with sodium ascorbate on the shear bond strength (SBS) of a universal adhesive to intracoronal bleached dentin. One hundred-and-twenty bovine dentin fragments were randomly divided into 12 groups (n=10), according to the bleaching procedure (unbleached and bleached) and restorative protocol (no treatment, 10% sodium ascorbate -10SA, 35% so...

AIM The aim of this study is to assess the effect of 35% sodium ascorbate on microtensile bond strength of dentin immediately after bleaching with 35% hydrogen peroxide. MATERIALS AND METHODS A total of 25 sound human 3rd molars were collected. Teeth were randomly divided into five groups for different treatments: Group I [bleaching + immediate bonding (i.e., restoration)], group II (bleachin...

We evaluated the efficacies of five treatment procedures for eliminating ascorbate interference in the enzymatic determination of urinary oxalate. Aliquots of urine samples, containing different amounts of added ascorbate and oxalate, were individually subjected to ferric chloride, sodium nitrite, sodium periodate, charcoal, or ascorbate oxidase treatment to eliminate ascorbate interference. Ox...

the mode of coordination of8 manganese(fi), cobaltm, nickel(h), copper(ii), zinc(h), lead(ii) and cadmium(i1) to sodium ascorbate (nahasc) was investigated using ir, uv-visible, aas, elemental microanalyzer, conductivity, magnetic and 'm and i3c nmr spectroscopic studies, nanasc is bidentate and coordination was through the carbonyl group and the oxygen atom of carbon-2 enolic hydfoxyl gro...

Despite its transport by glucose transporters (GLUTs) in vitro, it is unknown whether dehydroascorbic acid (oxidized vitamin C, DHA) has any in vivo function. To investigate, we created a chemical transport knockout model using the vitamin C analog 6-bromo-ascorbate. This analog is transported on sodium-dependent vitamin C transporters but its oxidized form, 6-bromo-dehydroascorbic acid, is not...

Oxygen inhibits polymerization of resin-based materials. We hypothesized that compromised bonding to bleached enamel can be reversed with sodium ascorbate, an anti-oxidant. Sandblasted human enamel specimens were treated with distilled water (control) and 10% carbamide peroxide gel with or without further treatment with 10% sodium ascorbate. They were bonded with Single Bond (3M-ESPE) or Prime&...

Regardless of bleaching regimes, the bond strength of composite resin or resin cement is reduced when bonding procedure is performed immediately after whitening. It is believed that the polymerization via free-radical mechanism is impeded by nascent oxygen remnant and peroxide in the bleached dental hard tissue. Because sodium hydroxide is used as a buffering agent to control the decreased pH, ...