The Role of Calcium Hydroxylapatite (Radiesse) as a Regenerative Aesthetic Treatment: A Narrative Review

Decoding the Implications of Glucagon-like Peptide-1 Receptor Agonists on Accelerated Facial and Skin Aging

Following the advent of glucagon-like peptide-1 receptor agonists (GLP-1RAs), subsequent unintended effects such as accelerated facial aging and altered skin health have been noted. This review delves deeper into the causative underlying mechanisms and provides insights into the intricate relationship between GLP-1RAs, adipose tissue, and premature facial aging, thereby highlighting the need for a nuanced understanding of their effects on facial alterations and skin health. Studies exploring the potential effects of GLP-1RAs on facial alterations and offering insights into the possible underlying mechanisms, causes, and clinical implications were included. The accelerated facial aging and altered skin health observed in GLP-1RA patients appears to be multifactorial, involving loss of dermal and subcutaneous white adipose tissue, and altered proliferation and differentiation of adipose-derived stem cells (ADSCs), and impacts on the production and secretion of hormonal and metabolic factors. These changes compromise the structural integrity and barrier function of the skin and may lead to diminished facial muscle mass, further exacerbating the appearance of aging. The insights presented call for a paradigm shift in the clinical management of facial changes induced by GLP-1RAs, with a focus on treatment strategies aimed at targeting ADSC stimulation. These include autologous fat transfers to reintroduce cells rich in ADSCs for rejuvenation, composite fat grafting combining autologous fat with/without stromal vascular fraction, and the strategic use of soft tissue fillers for volume restoration and biostimulation. This review highlights the potential role of GLP-1RAs in modulating adipose tissue dynamics, thereby contributing to accelerated aging through metabolic, structural, and hormonal pathways.

LEVEL OF EVIDENCE: 5

Long-term duration and safety of Radiesse (+) for the treatment of jawline

BACKGROUND

Calcium hydroxyapatite (CaHA)-carboxymethylcellulose (CMC)+ has unique properties that make it optimal for lifting, contouring, and defining the jawline. This long-term follow-up of a randomized, multicenter, rater-blinded trial reports efficacy and safety of CaHA-CMC(+) through 48 and up to 60 weeks post-treatment.

METHODS

Eligible patients were randomized (2:1) to the treatment or the control/delayed treatment group to receive CaHA-CMC(+) injections in both jawlines. While touch-ups were permitted 4 weeks post-treatment for both groups, only the treatment group was eligible for optional retreatment after 48 weeks. The primary outcome was ≥1-point improvement on both jawlines on the Merz Jawline Assessment Scale (MJAS); secondary endpoints included the Subject Global Aesthetic Improvement Scale (SGAIS) among others. Post hoc analysis included pooling up to 48-week data from the combined treatment and control/delayed groups and 60-week data for the treatment group.

RESULTS

Overall, 175 received treatment. MJAS responder rates were 77.9%, 78.7%, and 62.9% at 12, 24, and 48 weeks post-treatment, respectively. Responder rate on the MJAS at 60 weeks was 74.6% for those who received retreatment and 43.5% for those patients who received only the initial and touchup treatments. SGAIS scores demonstrated 93.4%, 85.6%, and 68.5% of patients rated themselves very much improved after 12, 24, and 48 weeks, respectively. Adverse events consisted of procedure or CaHA-CMC(+)-related events that were mostly resolved and overwhelmingly mild.

CONCLUSIONS

CaHA-CMC(+) produced clinically meaningful and long-lasting improvements in jawline contour and was well tolerated in patients through 60 weeks.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03583359.

LC-OCT as a tool to visualize in vivo location of dermal fillers

BACKGROUND

Dermal fillers have emerged as a popular non-surgical solution for facial rejuvenation and enhancement. Apart from botulinum toxin injections, they are the most common non-surgical procedure performed in the US. Line-field optical coherence tomography (LC-OCT; deepLive system Damae Medical, France) represents one of the most recent developments in non-invasive skin imaging technologies.

MATERIALS AND METHODS

We performed LC-OCT image acquisition on six patients that were treated with hyaluronic acid (HA) dermal fillers in various locations on the face. The images were acquired before the application of the fillers (T0), immediately after (T1), and at a 6- to 8-week (T2) follow-up visit.

RESULTS

At T0, we were able to appreciate a normal-appearing epidermis, dermoepithelial junction, and dermis. At T1, the intradermal filler deposits appeared as homogeneously hyporeflective areas, clearly discernible from surrounding vessels and other structures. At T2, the deposits were distinguishable as hyporeflective areas, although they were diminished in size compared to T1. On enface view, collagen fibers had increased thickness and were more homogeneously organized and hyperreflective.

CONCLUSIONS

We established the usefulness of LC-OCT in the non-invasive evaluation of dermal HA fillers to visualize both short-term and medium-term effects. LC-OCT may be a valuable tool in evaluating the precise location of filler placement and follow-up of resulting in vivo changes.

Guided SEFFI and CaHA: A Retrospective Observational Study of an Innovative Protocol for Regenerative Aesthetics

Background/Objectives: This retrospective observational study sought to determine the efficacy and safety of an innovative combined treatment protocol using guided Superficial Enhanced Fluid Fat Injection (SEFFI) and calcium hydroxylapatite (CaHA) in facial rejuvenation. Methods: A total of 158 patients (149 females and 9 males) underwent the combined treatment of guided SEFFI and diluted/hyperdiluted CaHA. The study evaluated treatment outcomes at 30, 90, and 150 days post-treatment using the Global Aesthetic Improvement Scale (GAIS) and three-dimensional photogrammetric analysis. Results: The combined treatment demonstrated consistent enhancement in skin quality and facial volume across temporal, malar, zygomatic, and jawline regions. At 90 days post-treatment, substantial improvements were observed, with the GAIS scores reflecting significant enhancements in both skin quality and volume, which were sustained or slightly improved by 150 days. Minor complications, predominantly ecchymosis at the injection sites, resolved within a week, confirming the treatments' safety. Conclusions: The integration of guided SEFFI and CaHA resulted in significant improvements in skin quality and facial volume with minimal complications. Further research is recommended to consolidate these findings and explore long-term outcomes.

A Structured Approach for Treating Calcium Hydroxylapatite Focal Accumulations

BACKGROUND

Radiesse, a widely utilized calcium hydroxylapatite (CaHA) dermal filler, has shown effectiveness in soft tissue augmentation and regeneration. As with all dermal fillers, the potential for nodules may arise. Understanding the pathogenesis of these nodules and exploring effective treatment methodologies are crucial for optimizing patient outcomes.

OBJECTIVES

A literature search was carried out to identify published literature documenting reversal of CaHA nodules. After identification, a consensus panel developed a structured approach, denoted by levels, for applying such reversal methods.

METHODS

This concise review presents an algorithmic approach to addressing CaHA focal accumulations (noninflammatory nodules) based on invasiveness, cost, and potential risks based on published literature.

RESULTS

Level 0 involves no intervention, relying on natural degradation for asymptomatic nodules. Level 1 interventions utilize mechanical dispersion techniques, including massage and in situ dispersion, which have demonstrated high success rates, cost effectiveness, and minimal invasiveness. Level 2 introduces alternative modalities such as pharmacological treatments with 5-fluorouracil and corticosteroids, lasers, and experimental approaches. Level 3 represents last-resort options, including calcium-chelating agents, manual removal, and surgical excision.

CONCLUSIONS

The article offers a structured approach to managing CaHA focal accumulations.

LEVEL OF EVIDENCE: 4

Improved brachial skin hydration and appearance with hyperdiluted calcium hydroxylapatite

INTRODUCTION

The search for minimally invasive treatments for areas not covered by clothing, such as the arms, has increased, particularly to combat flaccidity resulting from factors such as aging and weight loss. This study evaluated the efficacy of calcium hydroxyapatite (CaHA), an injectable biostimulator, in improving flaccidity and hydration of the skin of the arms.

MATERIALS AND METHODS

Six women between 40 and 50 years old with visible signs of brachial flaccidity were selected. Calcium hydroxyapatite was injected into the arms in a 1:4 dilution (1.5 mL per side), with subjective evaluation based on the GAIS score and objective hydration analysis using corneometry.

RESULTS

After a single application of CaHA, there was a significant increase in skin hydration (12.2%), objectively assessed by corneometry. Patient and physician satisfaction was high, evidenced by visible improvements in photographs and by the GAIS score. No significant adverse events were reported, demonstrating the safety of the procedure.

DISCUSSION

Our clinical observations confirm the ability of CaHA to visibly improve arm flaccidity. In addition, hydration measures support previous histological studies demonstrating increases in dermal proteoglycans. Compared to other studies, the increase in skin hydration with CaHA was similar to those obtained with hyaluronic acid, suggesting comparable results with a more comfortable and less invasive technique.

CONCLUSION

This study demonstrates the efficacy of CaHA in improving hydration of brachial skin after a single treatment. Despite the limitations of the sample size, the research contributes to the medical literature, highlighting the utility of the 3 mL CaHA presentation for brachial treatment with objective results in skin hydration.

A systematic review of Radiesse® (calcium hydroxylapatite): evidence and recommendations for the body

A filler composed of calcium hydroxylapatite and carboxymethylcellulose gel (CaHA/CMC) has been shown to possess biostimulatory and skin-tightening properties that have been applied not just to the face but also to the body to boost rejuvenation. Recently, evidence and recommendations for CaHA/CMC treatment of the face have been provided, but they are still lacking in terms of body treatment. This article aims to perform a systematic review of the literature on CaHA/CMC applications on the body and provide evidence from the literature. Currently, the only FDA-approved indication on the body is treating the hands and a recent European Union Medical Device Regulation approval has been released for decolletage treatment. The application of hyperdilutions on the neck, feet, arms, thighs, abdomen, and other body parts has been proven to provide a skin-tightening effect. However, despite their wide use with a good safety profile in clinical practice, recent trends and guidelines of diluted and hyperdiluted CaHA/CMC have yet to be supported by randomized controlled trials.

Calcium Orthophosphate (CaPO4) Containing Composites for Biomedical Applications: Formulations, Properties, and Applications

The goal of this review is to present a wide range of hybrid formulations and composites containing calcium orthophosphates (abbreviated as CaPO4) that are suitable for use in biomedical applications and currently on the market. The bioactive, biocompatible, and osteoconductive properties of various CaPO4-based formulations make them valuable in the rapidly developing field of biomedical research, both in vitro and in vivo. Due to the brittleness of CaPO4, it is essential to combine the desired osteologic properties of ceramic CaPO4 with those of other compounds to create novel, multifunctional bone graft biomaterials. Consequently, this analysis offers a thorough overview of the hybrid formulations and CaPO4-based composites that are currently known. To do this, a comprehensive search of the literature on the subject was carried out in all significant databases to extract pertinent papers. There have been many formulations found with different material compositions, production methods, structural and bioactive features, and in vitro and in vivo properties. When these formulations contain additional biofunctional ingredients, such as drugs, proteins, enzymes, or antibacterial agents, they offer improved biomedical applications. Moreover, a lot of these formulations allow cell loading and promote the development of smart formulations based on CaPO4. This evaluation also discusses basic problems and scientific difficulties that call for more investigation and advancements. It also indicates perspectives for the future.

A morphological analysis of calcium hydroxylapatite and poly-l-lactic acid biostimulator particles

Injectable fillers, pivotal in aesthetic medicine, have evolved significantly with recent trends favoring biostimulators like calcium hydroxylapatite (CaHA-CMC; Radiesse, Merz Aesthetics, Raleigh, NC) and poly-l-lactic acid (PLLA; Sculptra Aesthetics, Galderma, Dallas, TX). This study aims to compare the particle morphology of these two injectables and examine its potential clinical implications. Utilizing advanced light and scanning electron microscopy techniques, the physical characteristics of CaHA-CMC and PLLA particles were analyzed, including shape, size, circularity, roundness, aspect ratio, and quantity of phagocytosable particles. The findings reveal several morphological contrasts: CaHA-CMC particles exhibited a smooth, homogenous, spherical morphology with diameters predominantly ranging between 20 and 45 µm, while PLLA particles varied considerably in shape and size, appearing as micro flakes ranging from 2 to 150 µm in major axis length. The circularity and roundness of CaHA-CMC particles were significantly higher compared to PLLA, indicating a more uniform shape. Aspect ratio analysis further underscored these differences, with CaHA-CMC particles showing a closer resemblance to circles, unlike the more oblong PLLA particles. Quantification of the phagocytosable content of both injectables revealed a higher percentage of phagocytosable particles in PLLA. These morphological distinctions may influence the tissue response to each treatment. CaHA-CMC's uniform, spherical particles may result in reduced inflammatory cell recruitment, whereas PLLA's heterogeneous particle morphology may evoke a more pronounced inflammatory response.

Successful Treatment of Noninflammatory CaHA Nodules Using Focused Mechanical Vibration

Noninflammatory nodules arising from the injection of biostimulatory fillers persist as an unwanted complication. Pathologically, noninflammatory nodules may arise from superficial injection, accidental boluses, or incorrect concentration of microparticles contained within the filler. This case report introduces a method for reversing calcium hydroxylapatite (CaHA) using focused mechanical vibration. An in situ hyperdilution was created by injecting saline into the nodule core to prepare it for resuspension. Topical microneedling was subsequently applied to generate vibrations, aiming to disperse the accumulated CaHA particles. The outcome demonstrated a significant reduction in the size and visibility of the nodule. This combined saline-microneedling approach offers a potential noninvasive, nonpharmacologic solution for managing superficial CaHA nodules.

Level of Evidence 5

A systematic review of Radiesse/calcium hydroxylapatite and carboxymethylcellulose: evidence and recommendations for treatment of the face

Radiesse® is a filler composed of calcium hydroxylapatite microspheres suspended in a carboxymethylcellulose gel (CaHA/CMC). It has robust rheological properties that have been associated with its versatility. CaHA/CMC is employed for both on-label indications of filling wrinkles or lines, volumizing, and contouring of areas as well as off-label indications aiming at biostimulation and skin tightening. However, despite the expanding use of CaHA/CMC, overall evidence and recommendations for treatment are currently lacking. This paper aims to provide an up-to-date overview of CaHA/CMC clinical applications, together with a level of evidence of supporting literature, focusing on the face. Based on the data, CaHA/CMC may be considered a safe and effective treatment option for cheeks, jawline, HIV-related facial lipoatrophy, and nasolabial folds. Treatment of marionette lines, chin, pre-jowl, and corner of the mouth also tends to respond with a high degree of efficacy. Despite the recent trend, guidelines, and safety profile of diluted and hyperdiluted Radiesse® , no randomized controlled trials have been published.