How Does Injecting Filler Into Facial Ligaments Result in Facial Lifting?

BACKGROUND: Dermal filler injection can restore facial volume and improve contour; however, the precise mechanism underlying its lifting effect remains insufficiently characterized. This study explores how targeted filler placement within facial ligamentous structures contributes to mechanical support and contour elevation through anatomic, ultrasonographic, and biomechanical perspectives. METHODS: Cadaveric dissection and high-frequency ultrasonography were conducted to examine the morphology, orientation, and density of major retaining ligaments, including the zygomatic, mandibular, and platysmal-auricular regions. Observations were correlated with clinical facial dynamics to delineate how sub-SMAS filler deposition affects fibrous anchoring structures. RESULTS: Facial retaining ligaments were identified as collagen- and proteoglycan-rich fibrous condensations providing localized tensile resistance. Age-related attenuation of these structures reduces their capacity to maintain facial suspension. Targeted sub-SMAS filler injection increased local fibrous density and enhanced SMAS tension, thereby transmitting mechanical lift to the skin through ligamentous attachments. Region-specific reinforcement of dense anchoring zones produced efficient contour elevation with minimal filler volume. CONCLUSIONS: The lifting effect of filler injection arises from a synergistic mechanism that combines volumetric restoration with biomechanical reinforcement of fibrous anchoring structures. Understanding the regional variability and mechanical behavior of facial ligaments enables anatomy-based, low-volume rejuvenation strategies that preserve natural dynamics. Further clinical and quantitative biomechanical studies are warranted to validate these observations under physiological conditions.