Invisalign is a brand of clear, removable plastic aligners used to straighten teeth, providing a discreet alternative to traditional metal braces. A series of custom-made aligners are used to gradually shift teeth into their desired positions, with patients typically wearing them for 20 to 22 hours a day and switching to a new set every week or two. The process involves a dentist creating a 3D scan of the teeth to develop a personalized treatment plan and a digital model of the final result.