Bleached enamel is not conducive to immediate composite restoration. The use of oligomeric proanthocyanidin complexes as antioxidants enables an immediate composite restoration post bleaching. SUMMARYObjective: This in vitro study assessed the neutralizing effect of grape seed extract (oligomeric proanthocyanidin complexes [OPCs]) on the bond strength of bleached enamel. Materials and Methods: Labial enamel surfaces of 70 extracted human maxillary central incisors were randomly divided into four groups based on the antioxidant used as follows: Group I (n¼20): bleaching with 38% hydrogen peroxide gel for 10 minutes, without the use of an antioxidant; Group II (n¼20): bleaching followed by the use of 10% sodium ascorbate solution; Group III (n¼20): bleaching followed by the use of 5% proanthocyanidin solution; and Group IV (n¼10): control group in which no bleaching was done. Groups I, II, and III were further subdivided into two subgroups of 10 teeth each, based on whether composite buildup was done immediately (subgroup A) or after a delay of 2 weeks (subgroup B) post bleaching. Shear bond strength of the specimens was tested under a universal testing machine. The data were tabulated and statistically analyzed.Results: Significantly higher shear bond strength values were observed in teeth treated with 10% sodium ascorbate (Group II) and 5% proanthocyanidin (Group III) as compared with the control group (Group IV). Among the antioxidants used, teeth treated with proanthocyanidin showed significantly higher shear bond strength values than those treated with sodium ascorbate.Conclusion: It can be concluded that the use of grape seed extract prior to bonding procedures on bleached enamel completely neutral-*Sampath Vidhya, MDS, senior lecturer,

It can be concluded that dentin surface pretreatment with both 10% sodium ascorbate and 6.5% proanthocyanidin resulted in significant improvement in bond strength of resin composite to deep dentin.

The anatomical, physical and mechanical properties of non-coppiced and coppiced (after first felling) wood of Eucalyptus tereticornis were studied to evaluate their quality and to recommend it for various end uses. The pith to periphery variation in specific gravity, fibre length, fibre diameter, fibre lumen diameter, double wall thickness, vessel diameter and vessel element length were investigated in both types of wood. Correlation coefficients between anatomical characteristics and specific gravity and among anatomical characteristics were established. The results of physical and mechanical properties indicate that the timber from both non-coppiced and coppiced wood can be classified as very heavy, strong, tough, very hard but liable to warp and crack badly. The studies suggest that there is no significant difference in anatomical and mechanical properties of non-coppiced and coppiced wood suggesting their timbers can be utilized for similar purposes.

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