Aim: Chemical characterization of bleached turmeric hydro-alcoholic extract regarding amount of its curcuminoids, total phenols percent and antioxidant properties compared to unbleached turmeric hydro-alcoholic extract. Moreover, evaluate the effect of the bleached turmeric extract on dentin microhardness compared to sodium hypochlorite as an endodontic irrigant.
Methods: Quantification of curcuminoids was done by HPLC/MS test, evaluation of total phenols percentage was done using Folin-Ciocalteu reagent while antioxidant properties were evaluated using DPPH free scavenging ability. For the evaluation of microhardness, a total of 14 teeth were used. Mechanical preparation with intervening irrigation according to the corresponding group was done. Each tooth was then sectioned vertically into two halves and equally divided into two groups to be immersed in the corresponding irrigants. VHN was recorded before and after immersion. Statistical analysis of data obtained from microhardness test was performed on basis of p-value Results: Quantification by HPLC/MS test showed that the amount of the curcuminoid was lower in the bleached turmeric extract than the unbleached turmeric extract. Also, total phenols percent in the bleached turmeric extract was the least among the test samples while the antioxidant properties of the bleached turmeric extract was the highest among the tested samples. On the other hand, results of microhardness test revealed that both groups showed significant reduction in microhardness of root dentin after treatment.
Conclusion: Bleaching of turmeric affected its chemical properties and lowered its active agents and polyphenols content. Also, bleached turmeric extract had comparable effect to sodium hypochlorite on dentin microhardness.