Does a lip seal without proper tongue posture cause Hooked noses ?
Hi,
probably yes,
if you have an high, vaulted and downswung maxilla due to poor posture during growth that increases the "Mew indicator" , forcing the lip seal using the upper lip more.
It is less of a factor to that than the maxillary shape. The hook is from an underdeveloped upper jaw. Specifically...the dynamics of the nose is such...
So...to answer your question... a lip seal is a lip seal. If it applies pressure backwardly such as with meeting up with a lower recessed jaw's lip... it could possibly not be great. However, it's not the primary contributing factor.
Forgot to mention... shorter people usually have a stouter nose, because they eat facing up. Taller people usually get the hooked nose, because they eat facing down. Could be overall posture, but that does play a factor.