The primary action of the Masseter is elevation of the mandible (closing of the mouth) and is therefore one of the main muscles active during ‘chewing’ of food. Because of the leverage it develops on the mandible, it is considered as one of the strongest muscles in the body. When people come under stressful situations, they can often ‘clench’ their jaw or ‘grind’ their teeth, therefore, constantly contracting the masseter muscle. This can lead to tension headaches or possibly even myospasm or ‘lock-jaw’.
Option 1 ~ Beginning with a closed mouth and as relaxed jaw as possible, slowly and gently begin to open the mouth as wide as it will possibly go, as if you were performing a really large yawn.
Option 2 ~ Again, beginning with a closed mouth and as relaxed jaw as possible, place the pads of each thumb (or the tips of the fingers) into each masseter with a mild to moderate pressure, slowly and gently begin to open the mouth as wide as it is comfortable to do so.
- Superficial fibres – Zygomatic process (maxilla), the inferior border of zygomatic arch.
- Deep fibres – Posterior aspect of the inferior border of the zygomatic arch.
- Superficial fibres – Angle and ramus of the mandible.
- Deep fibres – Superior ramus and coronoid process of the mandible.
- Elevation of the mandible (closing the mouth or clenching the teeth).
- Anterior fibres – Protraction of the mandible.
- Posterior fibres – Retraction of the mandible.