Systems and methods are disclosed for forming a pontic in a polymeric shell dental appliance, including providing a polymeric shell dental appliance of the type which is removably placeable over a patient's dentition, said shell having a concave trough which conforms to the teeth when the appliance is placed over the dentition and a location in the trough corresponding to a missing tooth; and depositing a flexible, durably affixed material in the location to form the pontic.