Superficial muscular aponeurotic system (SMAS) is an area of musculature of the face. This muscular system is manipulated during facial cosmetic surgery, especially rhytidectomy. The SMAS extends from the platysma to the galea aponeurotica and is continuous with temporoparietal fascia and galea. It connects to the dermis via vertical septa.
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Superficial muscular aponeurotic system Wikipedia(Text) CC BY-SA