Bidental consonants are consonants pronounced with both the lower and upper teeth. They are normally found only in speech pathology. The Extensions to the IPA symbol is both a superscript and a subscript bridge, ⟨ ̪͆ ⟩.
Besides interdental consonants such as, which involve the tongue, there is at least one confirmed attestation of a true bidental consonant in normal language. The Black Sea sub-dialect of the Shapsug dialect of Adyghe has a voiceless bidental non-sibilant fricative where other dialects have, such as хы "six" and дахэ "pretty". Therefore it might best be transcribed phonemically as ⟨x̪͆⟩. However, there is no frication at the velum. The teeth themselves are the only constriction: "The lips fully open, the teeth clenched and the tongue flat, the air passing between the teeth; the sound is intermediate between and " (L&M 1996:144-145). This can be transcribed phonetically as, since has no place of articulation of its own.
The Extensions to the IPA specify one other purely bidental consonant sound, the bidental percussive.