DIGASTRIC

• Origin

Anterior belly: Digastric fossa of the mandible,
Posterior belly: Mastoid notch of the temporal bone

• Insertion

Intermediate tendon, which is anchored to the hyoid bone by a fibrous sling

• Agonist(s)

- Mylohyoid,
- Geniohyoid (for mandibular depression),
- Stylohyoid (for hyoid elevation)

• Antagonist(s)

- Masseter,
- Temporalis,
- Medial pterygoid (for mandibular elevation)

• Function

Depresses the mandible (opens the mouth).

Elevates the hyoid bone during swallowing and speaking.

TRIGGER POINT(S)

• Location

Trigger points are commonly found in both the anterior and posterior bellies of the digastric muscle.

They are typically located near the mandible and under the jawline, with the posterior belly accessible near the mastoid process.

• Pain Referral Pattern

Pain can refer to the lower front teeth, jaw, and upper neck.

Trigger points in the anterior belly can cause sensations in the lower incisors, while the posterior belly may refer pain toward the mastoid area, ear, and upper neck, sometimes causing tension headaches.

• Potential Causes

• Excessive talking, chewing, or singing
 

• Poor posture, particularly forward head posture
 

• Stress-related jaw clenching or teeth grinding
 

• Direct trauma to the jaw or neck
 

• Prolonged mouth opening, as with dental procedures.

• Prevention Tips

• Maintain good posture, particularly avoiding forward head position
 

• Use a mouthguard if bruxism is present
 

• Avoid prolonged jaw tension by taking breaks during speaking or chewing
 

• Practice relaxation exercises to reduce jaw clenching
 

• Perform gentle stretching exercises for the jaw and neck.