The Teeth

The teeth are areas of support for the tongue, or the lower lip to create zones of friction where the sound will be produced.

Teeth plays an articulatory role in the production of fricative consonants such as Fa (ف) which produces a sound like in the word "french" in english,

or ث(Tha) "th" which produces a sound similar of the one produced in the begining of the word "the" in english!