Invisalign has models that apply more force to the teeth, thus the time between each adjustment will be shorter than with traditional braces.
Yes and no. You can and indeed must take them out to clean them, and also when you are eating, but make sure that they are in your mouth for at least 20-22 hours a day.
You might still want to consider Invisalign braces, even if you are prone to losing your things. First off, the braces come with a case, to keep them clean but also so as to make sure you do not lose them. Second of all, they will spend the vast majority of time inside your mouth, so unless you lose your head you should be able to keep track of where they are at any given time.
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