Prospective comparative clinical study: Efficacy evaluation of collagen combined with hyaluronic acid injections for tear trough deformity.

The combined use of hyaluronic acid with collagen in injectable fillers corrected tear trough deformities and reduced the occurrence of the Tyndall phenomenon, which can be problematic with hyaluronic acid alone. Additionally, this combination may help overcome the disadvantage of a shorter retention period when using collagen alone.