Can the Hydrogel Form of Sodium Ascorbate be Used to Reverse Compromised Resin Infiltrant Penetration After Bleaching?

Abstract

Aims: The aim of this study was to investigate the effects of an antioxidant on the bleaching-induced reduction in the penetration depth of infiltrant resins. Materials and Methods: White spot lesions (WSLs) were created on 105 bovine tooth samples, each measuring 6 × 4 × 4 mm. Five samples were randomly selected for the examination of lesion characteristics. The remaining 100 samples were then divided into four groups (n = 25). In Group I, the WSLs were treated with resin infiltration (RI) only. RI was performed on Group II immediately after bleaching. In Group III, an antioxidant was applied for 2 h after bleaching, and this was immediately followed by RI. The Group IV samples were treated with RI at the end of a 1-week waiting period after bleaching. The penetration depths were evaluated through confocal laser scanning microscopy. Results: The lowest penetration rate, which was approximately 57%, was observed in Group II. This was followed by Group III (87%), Group IV (90%), and Group I (92%). Group II, in which the samples were infiltrated immediately after bleaching, had the lowest mean penetration percentage. All the bleached groups exhibited significantly lower penetration percentages than the nonbleached group (Group I) (P < 0.05). Antioxidant application increased the penetration significantly (P < 0.05). Conclusion: Application of sodium ascorbate was found to reverse the reduced resin penetration depth and penetration percentages resulting from bleaching. The postponement of adhesive procedures after bleaching yielded similar results.

Effect of antioxidant on tooth sensitivity after bleaching

“…15 Furthermore, numerous studies have examined the efficacy of sodium ascorbate in removing oxygen radicals generated by bleaching gels from enamel and dentin. 37,38,57…”

“…18 Over 20 studies have shown that a 10% SA concentration applied for regular application time (up to 10 min) is sufficient to neutralize the free oxygen present in enamel and dentin after bleaching and to restore the bond strength. 20,24,38 One study suggested that using antioxidant to neutralize the oxidizing effect of a bleaching agent requires at least one-third of the bleaching time to completely reverse its effect. 39 Another study found that a 15-min application of antioxidants was found to be adequate after three 15-min bleaching sessions, in line with our findings.…”

“…There are several concentrations and application times for sodium ascorbate 18 . Over 20 studies have shown that a 10% SA concentration applied for regular application time (up to 10 min) is sufficient to neutralize the free oxygen present in enamel and dentin after bleaching and to restore the bond strength 20,24,38 . One study suggested that using antioxidant to neutralize the oxidizing effect of a bleaching agent requires at least one‐third of the bleaching time to completely reverse its effect 39 .…”

“…This outcome was speculated to be associated with the diffusion of SA across the dentin disc and into the pulp space of the artificial pulp chamber (APC) 15 . Furthermore, numerous studies have examined the efficacy of sodium ascorbate in removing oxygen radicals generated by bleaching gels from enamel and dentin 37,38,57 …”

Using Resin Infiltration Technique and Direct Composite Restorations for the Treatment of Carious Lesions with Different Depths

“…Still, the vast majority stand behind the protective properties of resin infiltration. The overall success of the resin infiltration approach, including its masking effect, depends on the ability of the resin to infiltrate into porous spaces under an intact surface layer [ 18 ]. If cavitation has not occurred in the initial lesion, and the resin infiltration is performed as specified by the manufacturer, treatment will be successful.…”