Teeth whitening info

Bidental consonants, pronounced with both the lower and upper teeth, are normally found only in speech pathology. The Extended 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 bidental non-sibilant fricative where other dialects have [x], such as xə “six” and daxə “pretty”. Therefore it might best be transcribed phonemically as . However, there is no frication at the velum. The teeth themselves are the only constriction: “The lips [are] fully open, the teeth clenched and the tongue flat, the air passing between the teeth; the sound is intermediate between ‘ and ‘” (quoted in Ladefoged & Maddieson, The Sounds of the World’s Languages, pp 144-145). This can be transcribed phonetically as , since [h] has no place of articulation of its own.