title: An In-vitro Comparative Study of Shear Bond Strength of Composite Resin to Bleached Enamel using three Herbal Antioxidants.
abstract: BACKGROUND
  If adhesive restorations are carried out imme-diately, the Shear Bond Strength (SBS) to bleached enamel is reduced. The use of antioxidants can be highlighted since it seems to be a more effective alternative to reduce or remove the residual oxygen and immediate improvement in SBS.
  
  
  OBJECTIVE
  The purpose of this in-vitro study was an attempt to regain the lost bond strength, for which, the comparison of SBS of composite resin to bleached enamel was carried out using various antioxidants i.e., 5% grape seed extract, 5% pine bark extract, 5% pomegranate peel extract.
  
  
  METHODS
  Labial enamel surfaces of 50 extracted human maxillary central incisors were randomly divided into 5 groups based on the antioxidant used as follows: Group I (n=10): Bleaching with 40% hydrogen peroxide gel for 10 minutes, without the use of an antioxidant; Group II (n=10): Bleaching followed by the use of 5% grape seed extract solution; Group III (n=10): Bleaching followed by the use of 5% pine bark extract solution Group IV (n=10): bleaching followed by the use of 5% pomegranate extract solution; and Group V (n=10): Control group in which no Bleaching was done. SBS of the specimens was tested using universal testing machine. The data were tabulated and statistically analyzed using computer software Statistical Package for Social Sciences (SPSS) version 16.0. One-way analysis of variance (ANOVA) followed by Mann Tukey Post hoc test.
  
  
  RESULTS
  Mean SBS values were compared in all the groups and there was a statistically significant difference present among the groups (p<0.05). The SBS values were observed to be significantly higher in unbleached teeth (control group) followed by 5% pine bark extract, 5% grape seed extract, 5% pomegranate extract and the group in which teeth bleached with no antioxidant used.
  
  
  CONCLUSIONS
  The use of antioxidant immediately after bleaching the enamel surface, completely neutralizes the deleterious effects of bleaching and increases the SBS significantly. Among the antioxidants, 5% pine bark extract application after bleaching showed better bond strength.
authors.affiliation: Professor, Department of Conservative Dentistry and Endodontics, Meghna Institute of Dental Sciences , Mallaram, Telangana, India .
authors.forename: Pratap Kumar
authors.initials: PK
authors.lastname: Mukka
authors.affiliation: Professor, Department of Conservative Dentistry and Endodontics, Meghna Institute of Dental Sciences , Mallaram, Telangana, India .
authors.forename: Nanda Kumar
authors.initials: NK
authors.lastname: Komineni
authors.affiliation: Professor, Department of Conservative Dentistry and Endodontics, Meghna Institute of Dental Sciences , Mallaram, Telangana, India .
authors.forename: Sambashivarao
authors.initials: S
authors.lastname: Pola
authors.affiliation: Senior Lecturer, Department of Conservative Dentistry and Endodontics, Meghna Institute of Dental Sciences , Mallaram, Telangana, India .
authors.forename: E
authors.initials: E
authors.lastname: Soujanya
authors.affiliation: Senior Lecturer, Department of Conservative Dentistry and Endodontics, Meghna Institute of Dental Sciences , Mallaram, Telangana, India .
authors.forename: Anand Ramtheerth
authors.initials: AR
authors.lastname: Karne
authors.affiliation: Postgraduate Student, Department of Conservative Dentistry and Endodontics, Meghna Institute of Dental Sciences , Mallaram, Telangana, India .
authors.forename: Bhasker
authors.initials: B
authors.lastname: Nenavath
authors.affiliation: Postgraduate Student, Department of Conservative Dentistry and Endodontics, Meghna Institute of Dental Sciences , Mallaram, Telangana, India .
authors.forename: Sandeep
authors.initials: S
authors.lastname: Shiva
authors.affiliation: Postgraduate Student, Department of Conservative Dentistry and Endodontics, Meghna Institute of Dental Sciences , Mallaram, Telangana, India .
authors.forename: Pallavi
authors.initials: P
authors.lastname: Vuppunuthula
keywords: Bleaching; Grape seed extract; Pine bark extract; Pomegranate extract