Midface Multilayering Filler Injection Technique: Understanding of the Dynamic Facial Anatomy Through a "Smiling Cadavers" Anatomical Study.

Background: Understanding age-related changes in compartmentalized facial fat and their role in facial dynamics and aesthetics is essential to target filler injections for midface rejuvenation.

Methods: A novel anatomical approach ("smiling cadavers") was used to identify the main midface fat compartments involved during muscular contraction when smiling and their motion and behavior with and without filler injections. Based on these insights and the literature, a multilayering filler injection approach was developed to optimize midface rejuvenation by restoring fat volumes using rheologically different products injected into different fat compartments.