Systemic Review Compares Types of Dermal Fillers for Acne Scarring

Image Credit: © NDStock - stock.adobe.com

A comparative systemic review was published on the use of synthetic dermal fillers in treating acne scars.¹ Although most methods are efficient and safe, more reliable data is needed to determine which is most effective. Scarring occurs in up to 95% of patients with acne and these therapies are known for improving skin texture, elasticity, and volume while stimulating collagen.²

All literature was published between 2004 and 2024 on PubMed and ClinicalTrials.gov. Each included patients of any age and gender, as long as the sample included 10 or more participants in each study. For randomized controlled trials, the Cochrane Collaboration's Risk of Bias tool was used to assess the risk of bias. The Newcastle–Ottawa Scale was used for observational studies.

In the initial search, 401 trials were found. This was narrowed down to 26 studies, including a total of 1121 patients. The review included double-blind, single-blind, and open-label randomized studies, a nonrandomized trial, single-arm studies, retrospective analyses, and case series.

Further breakdown of the types of filler in each study is as follows:

• 14 studies on hyaluronic acid fillers (HA)
• 5 on polymethylmethacrylate fillers (PMMA)
• 4 on calcium hydroxy apatite fillers (CaHA)
• 2 on poly-l lactic acid fillers (PLLA)
• 1 on polycaprolactone fillers (PCL)

When HA fillers were used as a monotherapy, all trials saw favorable outcomes and significant improvement using the Global Aesthetic Improvement Scale (GAIS), Scale for Acne Scar Severity (SCAR-S), and Quantitative Global Scarring Grading System (QGSGS). One trial in particular saw improvement in 96% of participants after just 1 month. No serious adverse events were recorded in any of the studies.

Some studies also assessed the use of cross-linked and non-cross-linked HA as a combination treatment with therapies such as subcision, the dual-plane technique, triple step acne scar revision technique (TSART), botulinum toxin A, fractional CO₂ laser (FACL) treatment, and trifarotene.

In both the dual-plane technique and botulinum toxin A, researchers noted volume reduction and statistical improvement in atrophic and boxcar scars but saw no significant change in patient satisfaction. In TSTART treatment, statistically significant changes in clinical efficacy and patient satisfaction were seen, especially with rolling and boxcar scars.

For FACL treatment, only modest improvements in scarring were seen, particularly with non-cross-linked HA. With trifarotene therapy, atrophic acne scars were almost completely resolved, based on the Subjective Global Assessment (SGA) and Investigator Global Assessment (IGA) scores.

In the 2 studies that evaluated PLLA, both saw positive outcomes among 3 to 7 treatment sessions. One trial did note some adverse events of non-visible nodules, acne, and post-inflammatory hyperpigmentation.

CaHA was combined with energy-based devices and ultrasound-based interventions. Although improvement was seen when combining energy-based devices and CaHA, no synergistic benefit was seen when utilizing CaHA with ultrasound. Additionally, the trial that measured CaHA as a monotherapy saw results after 12 months but also observed adverse effects like extrusion, nodules, and further scarring.

PMMA was assessed using the Acne Scar Rating Scale (ASRS), and Physician and Subject Global Aesthetic Improvement Scales (PGAIS and SGAIS). High patient satisfaction was reported with only rare adverse events, like granulomas.

In the single PCL study, 10 patients saw improvement in the appearance of all types of acne scars. There were some adverse effects including localized edema, ecchymosis, and burning so further research is recommended to confirm its safety and efficacy, especially compared to other treatments.

“Across all fillers reviewed, safety remains a critical consideration,” the authors noted. “Besides PMMA, none of the injected fillers are FDA approved in treating acne scars. Nevertheless, HA has the most robust efficiency and safety record, with common side effects being localized and transient.”

Since most of the included studies had low-quality assessment scores and small sample sizes, the investigators strongly encourage further research to analyze these findings. These future studies should be randomized, controlled, and split face with the inclusion of more participants and scar subtypes.

References

1. Albargawi S. Synthetic Dermal Fillers in Treating Acne Scars: A Comparative Systematic Review. J Cosmet Dermatol. 2025;24(1):e16752. doi:10.1111/jocd.16752

2. Liu L, Xue Y, Chen Y, et al. Prevalence and risk factors of acne scars in patients with acne vulgaris. Skin Res Technol. 2023;29(6):e13386. doi:10.1111/srt.13386