Restor Dent Endod.  2013 Feb;38(1):43-47. 10.5395/rde.2013.38.1.43.

Effective application duration of sodium ascorbate antioxidant in reducing microleakage of bonded composite restoration in intracoronally-bleached teeth

• Park JY
• Kwon TY
• Kim YK

• KMID: 1995476
• DOI: http://doi.org/10.5395/rde.2013.38.1.43

Abstract

OBJECTIVES
The aim of this study was to determine an appropriate application duration of sodium ascorbate (SA) antioxidant gel in reducing microleakage of bonded composite restoration in intracoronally-bleached teeth.
MATERIALS AND METHODS
Eighty endodontically-treated human incisors were randomly divided into eight groups: control, no bleaching; IB and DB, immediate and delayed bonding after bleaching, respectively; S10m, S60m, S24h, S3d and S7d, bleaching + SA gel for 10 min, 60 min, 24 hr, 3 day and 7 day, respectively. For bleaching, a mixture of 30% hydrogen peroxide and sodium perborate was applied for 7 day. All access cavities were restored using One-Step adhesive (Bisco Inc.) and then Aelite LS Packable composite (Bisco Inc.). The bonded specimens were subjected to 500 thermal cycles, immersed in 1% methylene blue for 8 hr, and longitudinally sectioned. Microleakage was assessed with a 0 - 4 scoring system and analyzed using nonparametric statistical methods (alpha = 0.05).
RESULTS
Group IB showed a significantly higher microleakge than the control group (p = 0.006) and group DB a statistically similar score to the control group (p > 0.999). Although groups S10m, S60m, and S24h exhibited significantly higher scores than group DB (p < 0.05), the microleakage in groups S3d and S7d was statistically similar to that in group DB (p = 0.771, p > 0.999).
CONCLUSIONS
Application of SA gel for 3 day after nonvital bleaching was effective in reducing microleakage of composite restoration in intracoronally-bleached teeth.

Keyword

Application duration; Composite restoration; Intracoronal bleaching; Microleakage; Sodium ascorbate

MeSH Terms

Adhesives
Ascorbic Acid
Borates
Composite Resins
Humans
Hydrogen Peroxide
Incisor
Methylene Blue
Sodium
Tooth
Adhesives
Ascorbic Acid
Borates
Composite Resins
Hydrogen Peroxide
Methylene Blue
Sodium