I had recently seen a patient who was told by his orthodontist that the force of the tongue during the swallow is shifting his teeth. A few years ago, I might have agreed.
What I’ve learned through my orofacial myology training is that the thrusting of a tongue during swallowing or speaking is a sign of a much larger problem involving an improper oral rest posture. Slow, constant pressure (braces, for example) moves teeth. The rest position of the tongue could cause teeth to shift, but the force of the tongue during the swallow- or even many swallows each day- is not enough to cause these changes.
Check out this link for more information: https://orofacialmyology.com/parents-we-need-to-talk-about-orofacial-myology-disorders/