Clinical and histological comparative outcomes after injections of poly-L-lactic acid and calcium hydroxyapatite in arms: A split side study.

Background: Although much has been published on the use of poly-L-lactic acid (PLLA) and calcium hydroxyapatite (CaHA) for off-face indications, questions remain regarding their exact mechanisms of action in subcutaneous tissue and their comparative efficacy.

Objective: To present the clinical and histological results of the PLLA and CaHA injections into the opposing arms of the same patients.

Methods: Five women received superficial subcutaneous injections of PLLA into the left arm and CaHA into the right arm.