Kieferhebung

Kieferhebung, or jaw raising, is a term in articulatory phonetics describing the vertical movement of the mandible toward the maxilla during speech, resulting in a reduction of the vertical opening of the mouth. The degree of Kieferhebung varies with the phonetic demands of the produced sounds and is commonly studied in relation to vowel height and articulation. In general, higher vowels are associated with a more elevated jaw, while lower vowels involve a more open jaw; however, tongue height and lip rounding also influence the resulting articulation.

In practice, researchers measure or model Kieferhebung using imaging methods such as MRI and ultrasound, or integrate it into kinematic models for speech synthesis and phonetic analysis. The concept helps explain how jaw position affects acoustic parameters, particularly the first formant (F1), which tends to decrease as the jaw rises.

Beyond linguistics, the term may appear in dental or clinical discussions as a description of mandibular movement toward closed occlusion, but it is much less common in those contexts. The word derives from German: Kiefer (jaw) and Erhebung (raising).

See also: articulation, vowel height, formants, jaw movement.