Opalescence Endo non-vital whitening gel is formulated specifically to whiten endodontically treated discolored teeth using the “walking bleach” technique. Once Opalescence Endo gel is delivered to the pulp chamber, it should be sealed with a temporary cement, and left in the tooth for one to five days. Features: - 35% hydrogen peroxide. - Easy to place inside the pulp chamber. - 1–5 day treatment. - Use with Black Mini Tip. - Certified gluten free. - Certified kosher.