Modiolus is a point at the corner of the mouth or the angle of mouth where 8 muscles meet. It is also called as the Fibromuscular condensation where the extrinsic and intrinsic muscles meet together. This point is important in movement of facial muscles, facial expressions and in a treatment point of view for a dentist.
The extrinsic and intrinsic muscles which meet to form the modiolus are:
- Orbicularis oris
- Depressor anguli oris (or) triangularis
- Levator anguli oris (or) caninus
- Quadratus labii superioris
- Quadratus labii inferioris
- Zygomaticus major
Location and Shape of Modiolus:
- Modiolus lies about 10 to 12 mm lateral to the angle of mouth.
- Modiolus is shaped in the form of hub of a cart wheel.
Blood Supply and Nerve Supply to Modiolus:
- Blood Supply: Facial Artery
- Nerve Supply: Facial Nerve
How to Palpate Modiolus:
Place your Thumb on the skin and oppose it with your Index finger on oral mucosa and compress gently to feel the shape of the Modiolus between your thumb and index finger which is hub of cart wheel shape.
Functions of Modiolus:
Modiolus helps in Biting, Chewing, Drinking, Swallowing, Speaking and helps in various facial expressions.
Modiolus prevents food from being spilled out from the mouth by constricting the corners of mouth close to the pre molars during chewing.