The aligners may feel uncomfortable for the first few days as you get used to wearing them. Aligners work by putting gentle pressure on the teeth causing movement over time. Remember you are moving your teeth and the roots (which have sensitive nerves) of your teeth through delicate tissues. These tissues and teeth need to adjust to their new location and there is healing involved. Some people might be more sensitive and notice some soreness or moderate 'pain', especially when changing to new aligners. They may need to adjust their aligners a little bit using chewies or a nail file. We provide all the tools and instructions to make your transition as comfortable as possible. On a rare occasion, it will be necessary to make new impressions sometime during the aligner treatment process in order to ensure your aligners fit well. Usually this happens during the middle or end of a treatment process, but sometimes it can occur early on in the process.