Invisalign Clear Aligners are ideal for simpler orthodontic cases and people who want to avoid the braces "look." In my experience, they do work well, but in some cases it's faster to just put the braces on. While the trays are clear, they really aren't "invisible" and you can tell when someone is wearing them. They can also make it difficult to pronounce certain sounds, but you can usually adjust your speech pretty quickly. The trays are very tight and can be difficult to put in and take out. You can't eat or chew gum with them in, so there's also the awkwardness of having to take them out and put them back in if you're out to eat with someone. Some people need little pieces of composite attached to their front teeth to give the appliances something to grip to, and even though they match your teeth, you can still see them, even without the invisalign trays in. The advantage of invisalign is that you can have your teeth moved until you think they look good, then stop getting new trays (normally trays are changed every couple weeks or so).
San Antonio, TX