Bilayered structure of the superficial facial fascia

Background: The superficial facial fascia comprises the superficial musculoaponeurotic system (SMAS) and the temporoparietal fascia (TPF) and is regarded as a continuous monolayer. However, some evidence indicates that the superficial facial fascia consists of 2 layers in specific areas. Objectives: The authors evaluated the superficial facial fascia for bilayered regions. Methods: Twenty fresh cadavers (40 hemifaces) were dissected to observe the superficial facial fascia. Twelve cadavers were dissected to assess tensile strengths of the superficial and deep layers of the SMAS. Specimens were obtained from 2 cadavers for histologic analysis. Results: The SMAS and TPF were separable into superficial and deep layers, with intervening areolar tissue. The deep TPF was continuous with the deep SMAS inferiorly and the subgalea anteriorly. The superficial orbicularis oculi was invested by the superficial SMAS, whereas the deep orbicularis and the platysma were invested by the deep SMAS. Thus, 2 key structures addressed in facial rejuvenation are positioned in different surgical planes. Conclusions: Study results support the belief that the superficial facial fascia comprises 2 layers, with the superficial orbicularis oculi and platysma invested by different layers. These findings have implications for facial rejuvenation techniques that involve management of the SMAS and TPF.