The Hybrid Filler Technique: A 5-Year Retrospective Analysis

The combination of calcium hydroxylapatite (CaHA) and hyaluronic acid fillers (CPM-HA, cohesive polydensified matrix-based hyaluronic acid fillers, Belotero^® range, Merz Pharmaceuticals GmbH, Frankfurt, Germany), known as hybrid fillers, has emerged as a popular approach in aesthetic medicine. Premixed CaHA with CPM-HA offers several advantages, including enhanced tissue elevation and reduced early volume loss after injection.

The objective of the present study is to assess the safety of premixing CaHA and CPM-HA fillers for rejuvenation purposes or as an aesthetic harmonization treatment.

This retrospective study presents the clinical experience of two expert injectors who consistently used premixed CaHA and CPM-HA fillers for aesthetic treatments between March 2018 and December 2023. The premixed hybrid formulation was standardized and administered following a published protocol. A total of 2112 patients were treated, with meticulous follow-up over a minimum of one year.

In the 2112 patients treated, only 5 minor adverse events (0.24%) were reported. The adverse events consisted of 4 non-inflammatory nodules of which 2 completely resolved with hyaluronidase, and 1 case of transient edema. Secondary findings consist of the treated areas, type of CPM-HA used and mixing ratios that were applied.

The results from the current retrospective study, with the largest published cohort so far, are consistent with prior publications and strongly support a good safety profile of the CaHA:CPM-HA hybrid blend.

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