Effect of Catalase and Sodium Fluoride on Human Enamel bleached with 35% Carbamide Peroxide

Abstract

Aim: To evaluate the effects of postbleaching antioxidant application fluoridation treatment on the surface morphology and microhardness of human enamel. Materials and methods: Ten freshly extracted human maxil-lary central incisors were cut at cementoenamel junction. Crown portion was sectioned into six slabs which were divided into five groups: group A — untreated controls; group B — 35% carbamide peroxide (CP); group C — 35% CP and catalase; group D — treatment with 35% CP and 5% sodium fluoride; group E — 35% CP, catalase and 5% sodium fluoride. Thirty-five percent carbamide peroxide application included two appli-cations of 30 minutes each at a 5-day interval. After treatment, the slabs were thoroughly washed with water for 10 seconds and stored in artificial saliva at 37ºC until the next treatment. Two percent sodium fluoride included application for 5 minutes. Three catalase included application for 3 minutes. Results: After 5 days, groups B and C showed significantly decreased enamel microhardness compared to control. Group D specimens showed relatively less reduction in enamel micro-hardness than group C specimens. There is a marked increase in enamel microhardness in group E specimens. Conclusions: Fluoride take up was comparatively enhanced after catalase application resulting in less demineralization and increased microhardness.