Overview
Surgeons disagreed about how the SMAS relates to the expression muscles, the deep facial fascia and the facial nerve branches. The authors studied facial soft tissue anatomy in fresh cadavers and during surgery. The abstract is cut off at 250 words.
Findings
- Methods: fresh cadaver dissection plus several hundred dissections during surgery.
- Facial soft tissue is arranged in concentric layers: skin, subcutaneous fat, superficial fascia (SMAS), mimetic muscle, deep facial fascia (parotidomasseteric fascia), and the plane holding the facial nerve, parotid duct and buccal fat pad.
- The superficial fascia wraps the surface expression muscles: platysma, orbicularis oculi, and zygomaticus major and minor.
- The deep facial fascia continues from the deep cervical fascia of the neck up into the face.
- The facial nerve branches in the cheek lie deep to the deep facial fascia.
- In some regions the superficial and deep fascia are separated by a loose areolar plane; in others they are firmly joined by dense fibrous attachments.
- Retaining ligaments run from deep fixed structures to the skin and hold the soft tissue layers in place.
- Two types of retaining ligament exist: those arising from bone and those arising from other fixed structures.
What it means for a patient
- In the cheek, the facial nerve branches that move the face lie beneath the deep fascia layer. The authors state this is why the deep fascia matters.
- Retaining ligaments hold the facial layers in their normal position.
- Ask your surgeon which layer they work in and how they protect the facial nerve.
- The abstract is cut off, so results on aging and on rhytidectomy technique are not shown.
Why this paper matters
It described the face as concentric soft tissue layers and set out where the facial nerve lies relative to the deep fascia. It also classified retaining ligaments by origin. Cited 292 times (NIH iCite, 2026-09-25).
Terms
- SMAS (superficial facial fascia): the layer of muscle and fibrous tissue under the facial skin and fat.
- Mimetic muscles: the muscles of facial expression.
- Deep facial fascia (parotidomasseteric fascia): a thin firm layer covering the parotid gland and chewing muscle.
- Facial nerve: the nerve that moves the muscles of facial expression.
- Areolar plane: a layer of loose tissue that separates easily.
- Retaining ligaments: fibrous bands that hold facial soft tissue to bone or deeper structures.