Invisalign can intrude teeth mildly to moderately, but not in severe cases. You must remove Invisalign aligners to eat and drink, then replace them. Invisalign is designed to push teeth back into alignment using pressure from aligners and attachments. You can use a straw but should remove aligners first to avoid staining. Attachments do not chip aligners, which apply pressure to move teeth into position. You wear each aligner for 2 weeks for proper bone and gum adjustment during teeth movement. There are no food restrictions with Invisalign, only needing to remove aligners to eat or drink. Leaving aligners out for a day can disrupt the treatment process. You can drink alcohol after removing aligners.