Global Consensus Guidelines for the Injection of Diluted and Hyperdiluted Calcium Hydroxylapatite for Skin Tightening

BACKGROUND: Calcium hydroxylapatite (CaHA) is approved to correct moderate-to-severe wrinkles and folds and soft-tissue volume loss in the face and hands. More recently, subdermal injection using diluted CaHA has been used to improve skin laxity. OBJECTIVE To review evidence for the safe and effective use of diluted CaHA in the face and body and provide best practice recommendations. METHODS A global panel of expert aesthetic physicians convened to develop consensus-based guidelines for treating laxity and superficial wrinkles using diluted (ratio of 1:1) and hyperdiluted ($1:2) CaHA. RESULTS Diluted and hyperdiluted CaHA stimulates targeted neocollagenesis in the injection area to improve laxity and skin quality in the mid- and lower face, neck, décolletage, upper arms, abdomen, upper legs, and buttocks. Treatment can be used as an adjunct to volume augmentation or combined with additional modalities for optimal results. Adverse events are related to the injection and include bruising, swelling, mild pain, and induration. In thinner and darker skin, too-superficial injections of less diluted CaHA can lead to more adverse events. CONCLUSION This report provides preliminary guidelines for the novel off-label use of CaHA for biostimulation in the face and body. Further trials will provide additional clarity regarding treatment paradigms for optimal outcomes.