Impacts of Development, Dentofacial Disharmony, and Its Surgical Correction on Speech: A Narrative Review for Dental Professionals

Abstract

Speech is a communication method found only in humans that relies on precisely articulated sounds to encode and express thoughts. Anatomical differences in the maxilla, mandible, tooth position, and vocal tract affect tongue placement and broadly influence the patterns of airflow and resonance during speech production. Alterations in these structures can create perceptual distortions in speech known as speech sound disorders (SSDs). As craniofacial development occurs, the vocal tract, jaws, and teeth change in parallel with stages of speech development, from babbling to adult phonation. Alterations from a normal Class 1 dental and skeletal relationship can impact speech. Dentofacial disharmony (DFD) patients have jaw disproportions, with a high prevalence of SSDs, where the severity of malocclusion correlates with the degree of speech distortion. DFD patients often seek orthodontic and orthognathic surgical treatment, but there is limited familiarity among dental providers on the impacts of malocclusion and its correction on speech. We sought to review the interplay between craniofacial and speech development and the impacts of orthodontic and surgical treatment on speech. Shared knowledge can facilitate collaborations between dental specialists and speech pathologists for the proper diagnosis, referral, and treatment of DFD patients with speech pathologies.

Multitaper Spectrum Analysis of Consonants Produced by Patients With Dentofacial Disharmonies

“…With controls having the largest spectral amplitude followed by Class II non-AOB, and then all AOB, this could mean that Class II non-AOB patients are best able to posture so as to produce an alveolar constriction resulting in turbulence most similar to that produced by Class I controls. Most Class II patients present with deficient mandibles in which their tongues are also naturally positioned more posteriorly (see Bode et al, 2023 ), which contributes to a more similar constriction location compared to the controls. The AOB cohort has a more difficult time positioning the tongue tip and teeth to produce turbulence noise similar to that of the controls.…”

“… Grudziąż-Sękowska et al (2018) and Assaf et al (2021) found an association between malocclusion and speech distortion in children. See Bode et al (2023) for a more extensive review of the literature.…”