Craniofacial Muscles

10 Motor Control and Biomechanics of Laryngeal and Pharyngeal Muscles
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Table 10.2 Dilator and constrictor pharyngeal muscles: their insertion points, contraction effects, function for respiration and swallowing, and innervations
Muscle Insertions Effects of contraction Task function Innervation
Dilator muscles for inspiration
Levator veli From the petrous part
palatini
of the temporal
bone to the soft
palate
Tensor palatini From the medial
pterygoid plate to
the aponeurosis of
the palate
Genioglossus Genu of mandible to
tongue surface
Anterior belly of
the digastric
Internal surface of the
mandible to the
lateral surface of the
hyoid bone
Mylohyoid Lateral inner surface of
the mandible to the
aponeurosis of the
mylohyoid and the
anterior hyoid bone
Geniohyoid From the anterior hyoid
to the inner surface
of the mandible
Thyrohyoid Hyoid to the middle of
the lateral surface of
the thyroid cartilage
Elevates the velum to the
posterior wall of the
pharynx
Increased stiffness and pulls the
soft palate upwards towards
the posterior wall of the
pharynx
Moves the tongue forward,
tongue protrusion
Pulls the jaw open or elevates
the hyoid if the jaw is closed
Elevates the hyoid by stiffening
and shortening to elevate the
fl oor of the mouth
Inspiratory phase of respiration, also
active to close the nasopharynx
during swallowing and most speech
sounds
Aids in inspiration to elevate the soft
palate and during swallowing
prevents entry of the bolus into the
nasopharynx
Pharyngeal branch of the
vagus
Medial pterygoid nerve of
the mandibular branch
of the trigeminal
Inspiratory phase of respiration Medial branch of the
hypoglossal
Inspiratory phase of respiration, jaw
opening during most speech sounds
Active during swallowing to pull the
hyoid bone upwards towards the
mandible
Pulls the hyoid anteriorly Important for dilation of the hypopharynx
and elevation of the hyoid and
vestibule closure to prevent
aspiration during swallowing
Either lowers the hyoid or
elevates the thyroid cartilage
if the hyoid is held upwards
Active during swallowing to pull the
thyroid and larynx up beneath the
epiglottis
Mylohyoid nerve, a
branch of the inferior
alveolar nerve, and the
mandibular division of
the trigeminal
Mylohyoid nerve, a branch
of the inferior alveolar
nerve, off the
mandibular nerve, off
the trigeminal nerve
First cervical spinal nerve
branching off the
hypoglossal
First cervical spinal nerve
branching off the
hypoglossal
(continued)