How effective are the ivory white and bella brite for tooth whitening?

Not very effective: Just mild bleaching agents and techniques used to bleach people's teeth. They are safe to use so they won't hurt you. You may experience some sensitivity during and after use so take some advil or aleve (naproxen).

Not very effective: Both are mild whitening agents, as most over the counter products are. Without custom fitted trays by your dentist, the materials are weaker in order to protect your gum tissues. Because of the mildness of the material, they are also not very effective.

Marginal at best: For best results i recommend night time tray tooth whitening. Best otc combo is rembrandt deeply white paste and rinse.