ABSTRACT
Intelligible speech requires an anatomically and functionally intact velopharyngeal sphincter. Normal separation of oral and nasal cavities is essential. The anatomical elements of the sphincter mechanism include soft palate, posterior and lateral pharyngeal wall musculature and Passavant’s ridge. Soft palate elevation, reduction in pharyngeal lumen dimensions by lateral and posterior wall muscles and generation of intra-luminal negative pressure all improve the efficiency of vocal cord action and are all essential functional components for normal speech.
