title: Effect of bleaching on color change and surface topography of composite restorations.
abstract: This study was conducted to determine the effect of 15% carbamide peroxide bleaching agent on color change and surface topography of different composite veneering materials (Filtek Z350 (3M ESPE), Esthet X (Dentsply India), and Admira (Voco, Germany). Methods. 30 samples were fabricated for evaluation of color change using CIELAB color system and Gonioreflectometer (GK 311/M, ZEISS). 45 disc-shaped specimens were made for evaluation of surface topography after bleaching (Nupro White Gold; Dentsply) using SEM. Statistical analysis. One way ANOVA and Multiple comparison tests were used to analyze the data. Statistical significance was declared if the P value was .05 or less. Results and conclusion. All the specimens showed significant discoloration (ΔE > 3.3) after their immersion in solutions representing food and beverages. The total color change after bleaching as compared to baseline color was significant in Filtek Z350 (P = .000) and Esthet X (P = .002), while it was insignificant for Admira (P = .18). Esthet X showed maximum surface roughness followed by Admira and Filtek Z350. Bleaching was effective in reducing the discoloration to a clinically acceptable value in all the three groups (ΔE < 3.3).
authors.affiliation: Department of Prosthodontics, Center for Dental Education and Research, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Gunjan
authors.initials: G
authors.lastname: Pruthi
authors.forename: Veena
authors.initials: V
authors.lastname: Jain
authors.forename: H C
authors.initials: HC
authors.lastname: Kandpal
authors.forename: Vijay Prakash
authors.initials: VP
authors.lastname: Mathur
authors.forename: Naseem
authors.initials: N
authors.lastname: Shah