Hyaluronic Acid Filler Research Articles

Combination Procedure for Acne Scars Revision, Is It Needed?

Background: The treatment of acne scars is a problem for dermatologist. Varied morphology of acne scars makes the treatment more difficult. Combination technique has high efficacy than monotherapy. The challenge is how to select best combination procedure for scar revision.
 Case presentation: A 43-year-old male present with acne scars since 5 years ago. Dermatological findings revealed atrophic acne scars (ice pick, boxcar, rolling) types on forehead, nose and cheeks. Diagnosis established as moderate atrophic acne scars with global acne scarring system (GASS) is 21. Patient treated with blunt canula subcision, hyaluronic acid (HA) filler, microneedling radiofrequency, 90% trichloroacetic acid chemical reconstruction of skin scars (TCA CROSS) and application of salmon polydeoxyribonucleotide (PDRN). Patient also received topical 0.05% retinoic acid, 4% niacinamide, and sunscreen for daily. After 10 days, there is flattening and disappear of ice pick and boxcar, elevating of rolling scar, GASS score is 15. Blunt cannula subcision and HA filler is safe, effective for rolling scar through fibrous band breaking and prevent re-adhesion. Microneedling RF is effective for boxcar, otherwise 90% TCA CROSS preferrable for ice pick scars. This combination procedure leading cellular necrosis in epidermis, collagen in dermis, and stimulate regeneration. Application of Salmon PDRN may promote wound healing, hydrate the epidermis, and prevent dyschromia.
 Conclusion: Combination of subcision, dermal filler, microneedling radiofrequency, 90% TCA CROSS, and Salmon PDRN has high efficacy for scar revision through collagen remodelling and acceleration wound healing.

Hyaluronidase for Dermal Filler Complications: Review of Applications and Dosage Recommendations.

Hyaluronidase (Hyal) can reverse complications of hyaluronic acid (HA) fillers, which has contributed substantially to the popularity of such procedures. Still, there are differing opinions regarding Hyal treatment, including dosage recommendations in filler complication management. We aimed to address unanswered questions regarding Hyal treatment for HA filler complications, including timing and dosage, skin pretesting, properties of various Hyals and interactions with HA gels, and pitfalls of the treatment. PubMed and Google Scholar databases were searched from inception for articles on Hyal therapy for filler complications. Articles were evaluated regarding their contribution to the field. The extensive literature review includes international leaders' suggestions and expert panels' recommendations. There are limited controlled data but increasing clinical experience with Hyal treatment. The currently used Hyals provide good results and have an acceptable safety profile. Nonemergent complications such as the Tyndall effect, noninflamed nodules, and allergic or hypersensitivity reactions should be treated with low or moderate Hyal doses. Hyal should be considered with prior or simultaneous oral antibiotic treatment in managing inflammatory nodules. Hyal may be tried for granulomas that have not responded to intralesional steroids. Emergent complications such as vascular occlusion and blindness require immediate, high-dose Hyal treatment. Regarding blindness, the injection technique, retrobulbar versus supraorbital, remains controversial. Ultrasound guidance can increase the efficacy of the above interventions. Hyal is essential in aesthetic practice because it can safely treat most HA filler complications. Immediate Hyal treatment is required for emergent complications. Aesthetic practitioners should be versed in using Hyal and effective dosage protocols.

Use of Minimal Amounts of Hyaluronidase in the Ultrasound-Guided Treatment of Acute Vascular Occlusion by Hyaluronic Acid: A Preliminary Report

Abstract Background Complications from hyaluronic acid (HA) fillers are increasingly frequent, given the very high number of treatments performed every day worldwide. They are routinely treated with high doses of hyaluronidase, which can cause significant local and general unwanted effects. Objectives The aim of our work is to demonstrate that when the origin of the complication is precisely identified and treated under ultrasound guidance, a few hyaluronidase units are enough to treat it effectively. Methods Five young female patients came to our observation for vascular lesions from injection of HA fillers performed in the immediately preceding days, in 4 cases, and a few weeks earlier in the fifth case. All lesions were accurately identified by ultrasound and treated with hyaluronidase. Results The 4 promptly treated patients fully recovered with a hyaluronidase dose of 87 ± 44 IU (range, 30-150 IU). The fifth patient, treated later, markedly improved regarding clinical picture and symptoms. No early or late side effects have been reported from this hyaluronidase dosage. Conclusions Our data confirm that if the lesion at the origin of the skin damage is precisely localized with ultrasound examination and treated under ultrasound guidance, a few units of hyaluronidase, injected directly into the HA accumulation, effectively resolve the skin damage. At the doses we used, which were much lower than those usually recommended, hyaluronidase proved to be not only effective but also free of any side effects. Level of Evidence: 5

Evaluation of the Hydrophilic, Cohesive, and Physical Properties of Eight Hyaluronic Acid Fillers: Clinical Implications of Gel Differentiation.

Hyaluronic acid (HA) fillers are used to treat an array of aesthetic indications. Proper filler selection is paramount for successful patient outcomes. However, many important physiochemical and physical properties that impact HA gel behavior remain undefined. To evaluate the hydrophilicity, cohesivity and particle size of eight commercial HA fillers manufactured by either Non-Animal Stabilized Hyaluronic Acid (NASHA) or Optimal Balance Technology (OBT) techniques. Three individual in vitro experiments were performed to assess HA swelling capacity, cohesion, and particle size. Image analyses, blinded evaluation using the Gavard-Sundaram Cohesivity Scale, and laser diffraction technology were utilized, respectively. Compared to fillers manufactured with NASHA technology, OBT products demonstrated greater swelling capacity, cohesion, and wider particle size distributions. Strong positive correlations between swelling factor, degree of cohesivity, and increasing widths of the particle size distributions were observed. The hydrophilicity, cohesivity and particle size distributions vary among HA fillers manufactured with different techniques. The creation of new labels identifying products based on their unique combination of physiochemical and physical characteristics may help guide appropriate selection of HA fillers to optimize patient outcomes.

"Cohesiveness of Hyaluronic Acid Fillers": Evaluation Using Multiple Cohesion Tests.

Background Hyaluronic acid fillers can be manufactured using various processes. They have multiple properties, including their concentration, degree of modification, and rheological data. Cohesion is one such property to evaluate gel integrity; however, there is no standardized method for calculating this parameter. This study aimed to evaluate different tests for calculating hyaluronic acid cohesion and discuss the importance of hyaluronic acid cohesion as a consideration when selecting fillers. Methods The cohesion levels of five different hyaluronic acid fillers with different rheological properties were evaluated and compared using the drop weight, compression, tack, and dispersion time tests. Results The cohesion tests yielded different results in the samples. Samples 2 and 4 showed approximately two times the number of droplets when compared with Sample 5 in drop weight test. Samples 1, 2, 3, and 4 were superior to Sample 5 in tack test. Samples 1, 2, and 3 showed cohesive appearances at 95 seconds in most cases in dispersion test. Rheological test results did not reflect the measures of cohesion. Conclusion Although there are no definite standardized tests to evaluate the cohesion of hyaluronic acid fillers, our proposed tests showed similar results for different hyaluronic acid filler products. Further studies are needed to evaluate the cohesion of hyaluronic acid fillers and determine the clinical use of this distinguishing characteristic for clinicians selecting the product of choice. Level of evidence statement: These data are Level IV evidence.

Evolving Forehead Augmentation: A Five-step Approach with High G Prime Hyaluronic Acid.

Achieving effective upper-face rejuvenation through forehead augmentation is essential; however, complications such as vascular occlusion leading to skin necrosis or vision loss can occur. The complex forehead anatomy, characterized by ligaments and septa, often results in uneven outcomes with dermal filler treatment. The learning curve for successful forehead augmentation was longer than that anticipated. Herein, we present a specialized program for clinicians to expedite the learning process. This study explores a five-step technique for forehead augmentation using high elastic (G prime) hyaluronic acid fillers. We enrolled 10 Asian female participants with no history of dermal filler injections, surgery, or nonsurgical forehead procedures. All participants provided written informed consent, and their progress was assessed using photography and the Global Aesthetic Improvement Scale. Immediate post-treatment Global Aesthetic Improvement Scale ratings averaged 3.0 ± 0.0, decreasing to 2.5 ± 0.5 at 6 months, and 1.8 ± 0.6 at 12 months. Mild tenderness (10%), temporary swelling (30%), and a rapid recovery period underscored the safety and reliability of our approach. Importantly, no adverse vascular events were observed. Our five-step injection technique utilizing high-G prime hyaluronic acid leverages a profound understanding of the forehead anatomy, systematic methodology, and dynamic potential of advanced fillers. By implementing this paradigm, plastic and reconstructive surgeons can increase the standards of forehead augmentation and consistently achieve harmonious and effective results.

Safety and Efficacy Assessment of a Cross‐linked Hyaluronic Acid Dermal Filler for Correction of Moderate‐to‐Severe Nasolabial Folds in Skin Types III and IV

Introduction. Hyaluronic acid fillers are widely used to correct nasolabial folds. This treatment provides favorable aesthetic outcomes. The aim of this study was the safety and efficacy evaluation of Lunaphil Ultra intradermal filler for correcting nasolabial folds in the Iranian population with Fitzpatrick skin types III and IV. Methods. In this before and after clinical study, Lunaphil Ultra dermal filler was injected in nasolabial folds of 24 female and 6 male volunteers (mean age: 43.36 and SD: 11.55). Two independent physicians assessed the severity of nasolabial folds before injection and 2, 12, and 24 weeks later, according to the Allergan scale. The volume, depth, and area of both nasolabial folds and the thickness and density of the dermis in the right nasolabial fold were also measured. Adverse events and subject satisfaction were also recorded. Results. One grade or more improvement was detected in 81%, 57%, and 65% of participants at weeks 2, 12, and 24, respectively. The median score for the Allergan scale decreased significantly in all follow‐up visits. The median value of the area of nasolabial folds significantly reduced in all follow‐up visits. Two weeks after injection, dermis density showed a significant increase. The mean score for pain level during the injection was 1.96 out of 10. Adverse events were mild and transient. The median satisfaction scores were 9‐10 out of 10 at different visits. Conclusion. The findings showed that cross‐linked hyaluronic acid dermal filler containing lidocaine could be applied in clinical practice for correction of nasolabial folds in skin types III and IV, with high safety and efficacy. More comprehensive future research could approve these results. This trial is registered with IRCT20150101020514N11.

Safety and Efficacy of Using MaiLi® Precise by Mean of Intradermal Injections for Correcting Perioral Fine Lines

Introduction: Over the last twenty years, dermal fillers have become the backbone for rejuvenating the perioral area, which is one of the most difficult areas to treat. Due to the development of highly sophisticated fillers with radically different rheological properties and innovating techniques, it has become possible to correct specific regions with more natural results than before. This four-center pilot study sought to investigate the efficacy and safety of MaiLi® Precise in correcting fine-line wrinkles of the perioral area. Material and Methods: MaiLi® Precise is a recently introduced Hyaluronic Acid (HA) filler, harnessing the OxiFree™ technology, for suppleness, flexibility, and high longevity. These properties were deemed particularly suitable for correcting fine-line perioral wrinkles. All injections were performed using intradermal injections, with the fluid HA injected in a very superficial manner, resulting in the formation of very small papules at the wrinkle, disappearing within 1-2 hours. Follow-up occurred at one (T1) and three months (T2) post-injection. Treatment effectiveness was evaluated using the Global Aesthetic Improvement Scale (GAIS), as was the satisfaction of the subjects and investigators. Adverse Events (AEs) were also reported. Results: Overall, 20 patients aged 56 years on average, from four centers, were injected MaiLi® Precise into the perioral area to correct perioral lines using intradermal injections. No specific safety concerns were detected, given that AEs remained mild, were almost all resolved by T1, and were completely absent by T2. Patient and physician satisfaction were both >90% during follow-up. All physicians attributed improved, much improved, or very much improved GAIS scores at T1 and T2, indicating a marked improvement in appearance after injection. Conclusion: Based on the current study results, MaiLi® Precise was shown to be safe and provided satisfactory results from both the patient and the physician’s points of view during a 3-month follow-up.

Which Dermal Filler is Better for Penile Augmentation for Aesthetic Purposes? A Prospective, Single-Surgeon Study Based on Real-World Experience.

Several types of dermal fillers have been recently introduced and used for penile augmentation (PA). However, few studies have compared outcomes after the injection of different fillers. This study aimed to compare the clinical outcomes of hyaluronic acid (HLA), polylactic acid (PLA), and polymethyl methacrylate (PMA) filler injections, which are the most commonly used for aesthetic purposes. This prospective study was conducted for 24 weeks after a filler injection by a surgeon between March 2017 and December 2021. Healthy adult men complaining of small penis were enrolled. Penile girth, satisfaction, and injection-associated adverse events (AEs) were assessed at baseline and 4, 12, and 24 weeks after injection. Of the 301 men who received filler injections, 125, 134, and 42 received HLA, PLA, and PMA fillers, respectively. The augmentation effect was in the order of PMA, HLA, and PLA, respectively, at 24 weeks (PMA vs. HLA, p<0.001; HLA vs. PLA, p=0.006). Satisfaction levels increased significantly at 24 weeks in all groups (each with p<0.001). However, the increase in satisfaction levels was smaller in the PMA group (PMA vs. HLA or PLA, p<0.05, for both penile appearance and sexual life). No serious or systemic AEs were recorded. Filler injection-associated local AEs in the HLA, PLA, and PMA groups occurred in 9 (7.2%), 16 (11.9%), and 6 (14.3%) men, respectively. There was no significant difference in AEs among the groups (p=0.299). The augmentative effect was greater in the PMA group than in the HLA and PLA groups, whereas the increase in satisfaction levels was smaller in the PMA group. Our study demonstrated the clinical course of different types of fillers and suggests that the filler type should be selected after detailed counseling considering individual characteristics and preferences.

Неврологические осложнения в косметологии: обзор литературы

INTRODUCTION. The article discusses complications from the nervous system during such cosmetic procedures as botulinum therapy, the use of fillers, mesotherapy and thread lifting. AIM. Conduct an analysis of literary sources of domestic and foreign authors describing the modern understanding of neurological complications that arise in cosmetology practice. MATERIAL AND METHODS. An analysis of literature in Russian and English was carried out for the period from 2013–2024. Sources from the Russian scientific electronic library eLIBRARY, RSCI databases, and PubMed were used. RESULTS AND DISCUSSION. One of the most common neurological side effects of botulinum toxin is paralysis of the facial and masticatory muscles, innervated by the facial and trigeminal nerves, respectively. The mechanism of the negative effect of fillers on nervous tissue is associated, first of all, with their composition, which can have a toxic effect. During filler injections, nerve fibers can be damaged, which leads to disruption of the transmission of nerve impulses. The literature describes cases of deterioration or even loss of monocular vision, ptosis and ophthalmoplegia after injection of hyaluronic acid filler. A complication when using fillers based on hyaluronic acid and autologous fat is acute cerebrovascular accident. Prevention of neurological complications during cosmetic procedures is an important aspect of safety and successful results in aesthetic medicine.CONCLUSION. Neurological complications can occur as a result of various cosmetic procedures. The main factors are technique, lack of understanding of facial anatomy, and the use of low-quality drugs. It is important to be aware of the potential risks and contact only experienced specialists to reduce the likelihood of neurological complications. KEYWORDS: fillers, botulinum therapy, thread lifting, neurological complications, facial nerve neuropathy

Ultrasound characteristics of hyaluronic acid fillers tissue integration and hyaluronidase-mediated degradation

Ultrasound characteristics of hyaluronic acid fillers tissue integration and hyaluronidase-mediated degradation

The Role of Hyaluronic Acid Filler in Improving Neck Wrinkles: A Review and Outlook

The Role of Hyaluronic Acid Filler in Improving Neck Wrinkles: A Review and Outlook

In Vitro Cytocompatibility Analysis and Comparison of Different Hyaluronic Acid Fillers for Minimally Invasive Esthetics.

To overcome the natural visual consequences of the physiological aging process, the use of biodegradable fillers made of hyaluronic acid or sodium carboxymethyl cellulose is increasingly popular in modern esthetic medicine. Clinicians can choose from a wide range of fillers with variable compositions and rheological properties, and therefore with different application areas and injection depths. The aim of this study was to analyze and compare the most commonly used fillers for facial augmentation regarding their in vitro biocompatibility and to find potential correlations to their rheological properties. In the present study, direct and indirect in vitro cytotoxicity analysis according to DIN EN ISO 10993-5 were performed on 39 different filler materials for facial augmentation. All fillers analyzed in this study overall showed satisfactory results in the direct and indirect cytocompatibility tests. While no material was outside the threshold values in the 2,3-bis-(2-methoxy-4-nitro-5-sulphenyl)-(2H)-tetrazolium-5-carboxanilide (XTT) cell viability and bromodeoxyuridine (BrdU) cell proliferation assays or in the live-dead staining, only 7 out of the 39 fillers reached the required values in the lactate dehydrogenase assay. All biodegradable fillers examined in this study were found to be sufficiently cytocompatible. Although the qualitative analysis of the test results showed differences between the fillers, no concrete correlation between test performance and composition or manufacturer of the fillers was found. Future efforts are required to provide clinicians with even better support in choosing the right filler for optimal outcome and patient satisfaction.

Powikłania naczyniowe po zabiegach z zastosowaniem wypełniaczy na bazie kwasu hialuronowego

Aesthetic medicine deals with patients’ quality of life improvement by reducing imperfections in appearance. It focuses on inhibiting and slowing down ageing and wrinkles reduction. One of the most frequently performed procedures is hyaluronic acid fillers injections to fill and improve volume loss, deep folds and wrinkles. Those products have the gel characteristics, therefore their injection into the tissues may be associated with complications development, including vascular occlusion. The authors describe variety of possible vascular complications following aesthetic procedures with special attention paid to blindness and management algorithms in such cases.

MANDIBULAR FILLING

Context: Mandibular contouring is important for facial appearance and maintaining youth, as well as being key to defining masculine versus feminine facial features. Dermal fillers, for the most part, are non-invasive and temporary procedures, and may be a choice for correcting mild to moderate lack of definition in the mandibular contour of individuals who seek a less invasive treatment when compared to surgery or who have not yet decided to make permanent changes. in your facial appearance. Objective: To evaluate the effectiveness of the highly crosslinked hyaluronic acid-based filler, Restylane@LyftTM, for treating the mandibular line using the MD Codes technique. Methods: A brief literature review on jaw augmentation using injectable fillers, as well as a case report. Results: Observed through a quantitative evaluation method, obtained through stereophotogrammetry with the Vectra software, quantified through a metric scale of motion vectors and a metric scale of relief observed during treatment. Conclusions: There is high efficacy in the use of highly crosslinked hyaluronic acid filler, Restylane@LyftTM, using the MD Codes technique for volumization and redefinition of the mandibular contour.

A 52-Week Split-Face Study on the Efficacy and Safety of a New-Type Hyaluronic Acid Injectable Filler for Nasolabial Wrinkles

Background: The treatment outcome of nasolabial wrinkles or folds (NF) is widely considered a strong criterion for estimating the overall aesthetic results of different types of hyaluronic acid (HA) injectable fillers. These fillers have undergone various modifications and are classified as monophasic or biphasic, with monophasic fillers further divided into monodensified or polydensified. Objectives: This split-face study aimed to compare the effectiveness and safety of two monophasic HA fillers. Methods: A total of 15 facial aesthetic patients (mean age: 52.4 ± 9.39 years) participated in a split-face study to assess the clinical efficacy, long-lasting effect, and overall skin reaction of two different HA injectable fillers for nasolabial wrinkles. The right NF of each patient was treated with a monophasic, polydensified HA filler; however, the left NF was treated with a scientifically modified monophasic monodensified counterpart. The injection technique and HA quantity injected were consistent. The outcome was assessed using both the Wrinkle Severity Rating Scale (WSRS) and the Global Aesthetic Improvement Scale (GAIS) with analysis of variance (ANOVA) statistical methods. Additionally, the post-treatment naturalness feeling was measured using the FACE-Q questionnaire. Baseline photos were taken in standardized settings, and follow-up visits were conducted at the 1st, 6th, and 12th months. Results: Both HA injectables demonstrated similar effectiveness in terms of aesthetic outcome and long-lasting effect, as interpreted from WSRS and GAIS findings. However, the monodensified HA product received better subjective ratings for naturalness, as indicated by the FACE-Q questionnaire (P &lt; 0.05). Conclusions: Although there were no obvious signs of skin irregularity in both treated wrinkles, patients reported a feeling of intracutaneous tension in the right NF (treated with polydensified HA) but not in the left NF (treated with monodensified HA). Although some subjectivity exists in patient responses, the unanimous preference for the monodensified product due to its natural feeling provides strong support for its use in everyday aesthetic clinical practice.

Non-surgical Rhinoplasty (NSR): A Systematic Review of Its Techniques, Outcomes, and Patient Satisfaction.

Surgical rhinoplasty (SR), commonly known as nose job,is a widely practiced cosmetic surgery globally, aimed at addressing diverse aesthetic and functional concerns related to the nose. In recent years, non-surgical rhinoplasty (NSR) has gained popularity due to advanced techniques involving hyaluronic acid (HA) dermal fillers, offering advantages such as affordability, reduced side effects, and faster results. However, concerns persist about the suitability of dermal fillers for nasal anatomy and potential complications, prompting this comprehensive review. This study systematically evaluated the techniques, fillers, safety, and patient satisfaction associated with NSR, with the intent of providing valuable insights for clinicians and patients considering NSR or SR for improved aesthetic outcomes. The literature search, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria, yielded 16 relevant studies from an initial pool of 1002 articles. These studies covered various aspects of NSR, including techniques, complications, limitations, and positive results. In conclusion, NSR appears to be a quick and safe option for addressing minor nose shape issues, particularly through the use of HA fillers, but further discussion and standardization are necessary to address risks and limitations. A randomized controlled trial (RCT) using photographic evidence could significantly propel the progress of this evolving treatment. RCTs offer an optimal method to assess NSR's adverse effects and overall outcomes by allowing controlled comparisons between treatment and control groups. This approach minimizes biases and generates reliable statistical data, which is critical for evaluating safety, efficacy, and potential risks, thereby guiding informed clinical decisions.

What is 'botox', what are fillers, and how safe are these cosmetic injectables?

Botulinum neurotoxin type A (BoNT-A, popularly referred to as 'botox') is a muscle-relaxant that is injected into the mimic facial muscles to soften wrinkles in more than two percent of Dutch women annually. A similar number of women undergo filler injections with hyaluronic acid hydrogels, used to counteract the aging appearance of the skin, or to create desired facial contours. Complications are generally mild in nature and rare (certainly compared to surgical complication rates) and include nodules, bumps and a temporary heavy feeling of the eyebrows. Vascular complications related to filler injections (1:7000) can potentially lead to unilateral blindness or skin necrosis. In the Netherlands, the risk of blindness over the past six years is estimated to be 1 in every 1.4 million filler injections. Permanent skin damage due to gangrene has never been reported in the Netherlands. In conclusion, BoNT-A and hyaluronic acid filler injections are safe procedures in the hands of appropriately trained healthcare professionals.

Current Landscape of Hyaluronic Acid Filler Use in the United States.

Hyaluronic acid (HA) fillers are among the most used fillers for soft-tissue augmentation. There are now many FDA-approved HA products, and the successful use of injectable HA fillers requires an understanding of the available options.&nbsp; Objective: The purpose of this manuscript is to provide a comprehensive list of HA fillers and their indications. An overview of their biochemical properties and formulations will aid dermatologists in appropriate use. A comprehensive search of all the FDA-approved dermal fillers was conducted via the FDA "pre-market approval" (PMA) site. Additional details regarding filler properties were obtained using the respective agent's package inserts.&nbsp; Results: A total of 28 HA dermal fillers were identified and key pharmaceutical properties were discussed. These findings will help the physician match the appropriate HA filler with the area that is to be treated.&nbsp; Conclusion: Understanding the available fillers and their properties can help physicians select the appropriate fillers for more predictable and sustainable results.&nbsp; J Drugs Dermatol. 2024;23(1):1247-1252. &nbsp;&nbsp; doi:10.36849/JDD.7858.

Differentiation of NASHA and OBT Hyaluronic Acid Gels According to Strength, Flexibility, and Associated Clinical Significance.

With a wide range of hyaluronic acid (HA) filler products available, knowledge of gel characteristics is a key part of tailoring treatments to each patient's aesthetic goals. This paper presents 2 main gel characteristics - strength/firmness and flexibility - for HA fillers produced using NASHA&reg; and OBT&trade; and their clinical significance for tissue performance. Three NASHA gels (Restylane&reg;; Restylane Silk; Restylane Lyft) and 4 OBT gels (Restylane Refyne; Restylane Kysse; Restylane Volyme; Restylane Defyne) were studied in dynamic mode using a PP25 rheometric measuring system at 25 degrees C. Gel strength/firmness was measured using frequency sweep, with G prime evaluated at 0.1 Hz. Flexibility assessments used amplitude sweep measurements between 0.1% and 10,000% strain at 1 Hz, with xStrain being the strain value at the crossover point where G prime and G double prime have the same value.&nbsp; Results: Restylane, Restylane Silk, and Restylane Lyft had G primes of 701, 416, and 799 Pa, respectively. OBT G primes for Restylane Refyne, Restylane Kysse, Restylane Volyme, and Restylane Defyne were 70, 160, 171, and 271 Pa, respectively. The xStrain values were 1,442% (Restylane Refyne), 908% (Restylane Kysse), 930% (Restylane Volyme), 761% (Restylane Defyne), 7% (Restylane), 19% (Restylane Silk), and 17% (Restylane Lyft).&nbsp; Conclusions: OBT products had high flexibility (tolerance to deformation) and low to intermediate strength/firmness, which make them appropriate for dynamic facial areas. NASHA products showed greater strength/firmness, with the potential to create lift and projection. Altogether, NASHA and OBT HA gels covered a wide range of strength and flexibility. J Drugs Dermatol. 2024;23(1):1332-1336.&nbsp; &nbsp;&nbsp; doi:10.36849/JDD.7648.