No, we only need one good set of impressions from you. Our dental team will use these to create a whole treatment plan for you. However, the human body is not a machine, so we can't predict how your teeth and mouth will react 100%. Sometimes it will be necessary to ask you to make a new set of impressions part-way through the process in order to make your smile journey more efficient and comfortable. Although we understand that this might seem a bit inconvenient, it is can be part of the process. There is no additional charge for this type of impression retake and new aligners. Note that this is not considered a 'defect' in the aligners.