A patient with esthetic concerns has multiple interincisal diastemas, makes sibilant (whistling) sounds, and cannot whistle. What is the cause of the altered speech?

Open contacts/diastemas allow air to escape between the teeth, disrupting sibilant ('S') sounds and the ability to whistle; closing the spaces restores normal airflow and speech.Other options: Increased VDO causes clicking and muscle fatigue; ankyloglossia limits tongue movement (affecting different sounds); a cleft palate causes hypernasality, not whistling from anterior spaces.Key exam takeaway: Anterior diastemas allow air escape that distorts sibilants and whistling; closing the spaces corrects it.