The duration of the whitening effect with Magic Smile bleaching protocols can vary: Gentle Protocol: Up to 12 months. Balanced Protocol: Up to 15 months. Maximum Strength Protocol: Up to 16 months. For maximum and longer-lasting results, it's recommended to use Magic Smile Home Kits 2-5 days after the in-office teeth whitening procedure, which can extend the duration by up to 12 months in addition to the chosen protocol. So, the maximum duration of teeth whitening effects can be extended up to 24-28 months when a full course of home whitening is followed immediately after an in-office procedure, and supportive home procedures are done every 6 months. IMPORTANT: Any teeth whitening is temporary due to the porous nature of enamel. New pigment constantly accumulates inside the tooth, while plaque forms on the outside. While the whitening procedure helps remove accumulated pigment, it can reaccumulate over time due to factors like diet, smoking, and oral hygiene. Therefore, whitening results are not permanent, and maintenance may be required to keep teeth looking their best.