How can cleft palate contribute to hypernasal speech?

A cleft palate contributes to hypernasal speech primarily by preventing the necessary velopharyngeal closure—the seal between the soft palate and the pharynx—required to direct airflow through the mouth during speech.12

When this closure is absent or incomplete, air escapes through the cleft into the nasal cavity instead of being contained within the oral cavity. This results in several specific speech complications:12

• Abnormal Nasal Resonance: The unintended passage of air into the nasal chambers gives oral speech sounds an abnormal, nasal quality.2
• Loss of Intraoral Pressure: Because air leaks through the nose, the individual cannot generate the pressure required to articulate certain sounds properly. This particularly affects plosive sounds (such as P) and sibilant sounds (such as S), which become distorted or impossible to produce correctly.12
• Compensatory Behaviors: Individuals may attempt to overcome these mechanical limitations by constricting their nostrils or shifting the articulation of sounds down into the pharynx or larynx, which can further alter speech patterns.2

Effective management typically involves a multidisciplinary team, including surgeons and speech pathologists, to repair the palate and provide necessary speech therapy.12