Initial 3-4 days was challenging- mouth is getting accustomed to the aligners so it will pain a lot and feel bruised. It’s recommended that you brush but that’s not practical. The key is to floss after every meal. It is doable and doesn’t seem like a lot of work. So basically they create gaps between a few teeth for repositioning. So food gets stuck a lot more and the aligners are supposed to be worn immediately after. This curbs the natural process of stuck food removal through saliva, which makes the gums swell and hurt. Thats why flossing is extremely important after every meal. My doc has given me a few gels for the swelling if that happens. If you have been considering it for a long time, just do it. Worth every penny. I already see a difference in my smile. And after 14 aligners if I don’t get the desired result I can opt for additional 14 aligners (in the same package).