The labial frenum connects your top lip to the gum area right above your front teeth. If this frenum is shorter than average, it can cause difficulty in speech development. This condition is a type of lip adhesion. 

A lip adhesion can also pose a problem with dental development and make it hard to fully clean the gums and front teeth.

This raises the risk of gum disease and other dental complications. A maxillary frenectomy can give the upper lip more mobility.