Rheological and Structural Analysis of Hyaluronic Acid Fillers Used for Chin Augmentation.

Area of Science:

• Aesthetic Medicine
• Dermatology
• Biomaterials Science

Background:

• Hyaluronic acid (HA) fillers are widely used for chin contouring and projection in aesthetic procedures.
• The physicochemical and viscoelastic properties of HA fillers significantly impact their clinical performance.
• Understanding these properties is crucial for optimizing aesthetic outcomes.

Purpose of the Study:

• To compare the properties of four HA filler gels for chin projection: JUVÉDERM® VOLUX, RESTYLANE® LYFT, PERFECTHA® SUBSKIN, and RESTYLANE® SHAYPE.
• To evaluate how variations in filler properties influence suitability for chin augmentation.

Main Methods:

• Characterization using scanning electron microscopy, dynamic light scattering, zeta potential, and swelling factor (SF).
• Rheological assessments including frequency sweep, amplitude sweep, and cohesivity modulus (MOC).
• All tests were conducted in triplicate for reliability.

Main Results:

• JUVÉDERM® VOLUX showed the highest swelling capacity (SF 3.28-3.37), while RESTYLANE® LYFT had the lowest (SF 1.53-1.66).
• RESTYLANE® LYFT and RESTYLANE® SHAYPE exhibited higher storage modulus (G') values, indicating greater stiffness.
• RESTYLANE® SHAYPE and PERFECTHA® SUBSKIN demonstrated higher cohesivity modulus (MOC), suggesting superior resistance to deformation.

Conclusions:

• RESTYLANE® SHAYPE presented a favorable balance of moderate swelling, high G', and elevated MOC for chin contouring.
• The selection of HA fillers should consider patient anatomy, aesthetic goals, and injector expertise.
• No single filler is universally superior; tailored selection is key for optimal results.