Tongue ties prevent the tongue from being able to have the full range of motion that they ought to. A loose frenum allows the tongue to move further upwards or out of the mouth. If a person has restricted tongue movement, a tongue tie is likely to blame.
The lingual frenum is the strip of skin just under your tongue. It attaches somewhere towards the middle-to-anterior belly of the tongue (hence the name “lingual”) to the floor of the mouth.
Lingual frenums vary from person to person. In some cases, they can be extremely short. When such is the case, a “tongue tie” exists.