Efficacy of In-office Bleaching on Microhardness of Permanent Teeth with Antioxidant Re-hardening

Table 1: Bleaching materials.

Bleaching Material	Manufacturer	Active Ingredient
Zoom 2 Gel	Discus Dental, USA	25% Hydrogen peroxide, KNO₃, ACP
Zoom AP Light	Discus Dental, USA	Sodium free, 25 W short arc halide lamp, 350-600 nm
Opalescence Boost Gel	Ultradent Products Inc., USA	38% Hydrogen peroxide, NaF