How do bleaching trays cause gum sensitivity?
When a dentist custom fabricates a bleaching tray for a patient they will usually make the it out of a soft flexible plastic that has been trimmed in a scalloped fashion so the edges of the tray end just at the user’s gum line. This type of bleaching tray design minimizes any mechanical trauma that might occur due to the edges of the tray rubbing against the user’s gums. It also minimizes the contact of the peroxide bleaching gel with the gums.
