Break the Matrix

Visibility of buccal corridors when smiling is directly correlated with how wide and forward your palate is. In ideal conditions a combination of facepulling, NCR and mewing may fix this over time. Are you sure you need to wear retainers even if you're mewing?


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Your tongue is a natural palate expander. If you can fit it between your teeth, use it. Retainers hold your teeth in place, not the maxilla.

I understand this, but I am still having trouble keeping my mouth shut when I am sleeping, I don't mouth breathe but my mouth falls open.
Are there no appliances I can use to speed up this process? Palate expander, etc?

Keeping mouth shut during sleep is mostly a matter of body mechanics. You have to keep your head and neck in an angle that keeps your jaws shut naturally. Which means tucking your chin in and keeping neck straight; the opposite of the head forward posture.

You can achieve this when sleeping on your side, but it's most optimal when sleeping on your back with head and neck elevated a bit. If your maxilla is recessed, you probably can't sleep on your back without snoring / sleep apnea though.

In addition, good tongue posture should create a slight vacuum in your mouth which helps to keep it shut. As for palate expanders I have no experience about them, but a variety of appliances exist.