Each syringe delivers 3-4 applications for both top and bottom teeth. Most people need 7-14 applications (once per day,) to completely remove all stains from their teeth. This varies from person to person depending on the type and severity of stains on the teeth, as well as the length of time per application.
Keeping a white smile requires occasional maintenance. Since the teeth whitening gel is cheaper when purchasing trays, we recommend that you purchase more gel in the original kit. Our teeth whitening gel and desensitizing gel both have a 2-year shelf-life when refrigerated, or 1-year unrefrigerated so purchasing extra gel will ensure you are able to keep your teeth stain-free.