This is a common question I get asked. The string under the tongue is called a frenelum which is made mostly of fascia, type 1 collagen which does not stretch (Mills, 2019, Martinelli, 2014).
Babies don't "grow out" of tongue ties they just learn to compensate in order to "get by". This causes a snowball effect of oral disfunction which can have impacts throughout the lifespan, such as picky eating, head, neck and jaw pain, and sleep disordered breathing.
Remember a tongue tie is diagnosed based on anatomy, mobility AND function. If it's not impacting function it's not a true tie and we don't treat it.
Is this tongue tie talk new to you or have you heard this before? Let me know!