Systematic Review of Clinical Trials of Small- and Large-Gel-Particle Hyaluronic Acid Injectable Fillers for Aesthetic Soft Tissue Augmentation

Impurities in Hyaluronic Acid Dermal Fillers? A Narrative Review on Nonanimal Cross-Linked Fillers

Importance: Nonanimal cross-linked hyaluronic acid (HA) dermal fillers are among the most versatile tools in minimal invasive esthetic medicine. Filler injections aim to volumize, provide contour, and reduce wrinkles and skinfolds. In the hand of the experienced user, HA fillers have an excellent safety profile. Nevertheless, adverse events have been reported related to poor injection techniques, infection, and immune reactions. Observations: In this review, the focus is on filler impurities. Impurities can originate from the fermentation process, crosslinking, packaging, and contamination. Impurities consist of particular and nonparticular matter. We discuss possible risks for the patient to be treated with HA fillers. Conclusions and Relevance: Impurities of dermal fillers bear a potential risk for patients, such as delayed autoimmune and inflammatory reactions, biofilm formation, and exposure to leachable Endocrine Disrupting Chemicals. Amount and quality of impurities can be considered as one of the quality parameters of commercially fillers. Considering patient safety, filler impurities should be further reduced.

Long-term Safety and Effectiveness of Hyaluronic Acid Fillers Correcting Nasolabial Folds in Chinese Patients

Background

Soft-tissue fillers, specifically hyaluronic acid fillers, can reduce many signs of aging by treating the associated loss of subcutaneous fat and midfacial contour deficiencies. The objective of this study was to investigate whether the effectiveness and safety of Belotero Volume Lidocaine (BVL) compared with Restylane (RES, control) is noninferior in the treatment of severe nasolabial folds (NLFs) in Chinese patients.

Methods

This was a prospective, randomized, controlled, split-face clinical study. Overall, 220 Chinese patients of both sexes with symmetrical NLFs of severe intensity (grade 4) on the Wrinkle Severity Rating Scale (WSRS) were treated with both fillers. Treatment outcomes were assessed by the WSRS, and other scales, at multiple time points up to 18 months postinjection. The co-primary effectiveness outcomes were based on the blinded evaluator ratings of NLFs according to the WSRS scale after 6 and 12 months. Adverse events were assessed during the whole study and patients' pain sensation at three time points after injection.

Results

Noninferiority of BVL versus control based on the WSRS was demonstrated at month 6 and month 12. Response rates were slightly higher for BVL than control at all time points, and BVL had a sustained effect until month 18. Pain sensation scores were significantly lower for BVL compared with control. The incidence rates of treatment-related AEs were low and very similar for both treatments.

Conclusions

This study demonstrates that BVL is a safe, long-lasting, and effective treatment to correct severe NLFs in Chinese patients while being noninferior to the control device.

Polysaccharide-based nanoassemblies: From synthesis methodologies and industrial applications to future prospects

Polysaccharides, due to their remarkable features, have gained significant prominence in the sustainable production of nanoparticles (NPs). High market demand and minimal production cost, compared to the chemically synthesised NPs, demonstrate a drive towards polysaccharide-based nanoparticles (PSNPs) benign to environment. Various approaches are used for the synthesis of PSNPs including cross-linking, polyelectrolyte complexation, and self-assembly. PSNPs have the potential to replace a wide diversity of chemical-based agents within the food, health, medical and pharmacy sectors. Nevertheless, the considerable challenges associated with optimising the characteristics of PSNPs to meet specific targeting applications are of utmost importance. This review provides a detailed compilation of recent accomplishments in the synthesis of PSNPs, the fundamental principles and critical factors that govern their rational fabrication, as well as various characterisation techniques. Noteworthy, the multiple use of PSNPs in different disciplines such as biomedical, cosmetics agrochemicals, energy storage, water detoxification, and food-related realms, is accounted in detail. Insights into the toxicological impacts of the PSNPs and their possible risks to human health are addressed, and efforts made in terms of PSNPs development and optimising strategies that allow for enhanced delivery are highlighted. Finally, limitations, potential drawbacks, market diffusion, economic viability and future possibilities for PSNPs to achieve widespread commercial use are also discussed.

A Multicenter Noninferiority Study Comparing Safety and Effectiveness of Hyaluronic Acid Fillers for Correction of Nasolabial Folds in Chinese Subjects

Hyaluronic acid fillers are the preferred choice for minimally invasive facial volume restoration. In this study, a split-face design was used to compare the effectiveness and safety results of Belotero Balance Lidocaine (BEL) and Restylane (RES, control) to investigate whether BEL is noninferior compared with RES in nasolabial fold (NLF) correction.

Methods

This was a prospective, controlled clinical study in Chinese subjects. Subjects with symmetrical moderate NLFs according to the Wrinkle Severity Rating Scale were randomized to receive BEL in one NLF and RES in the other. The primary objective was to investigate whether BEL is noninferior compared with RES after being injected mid-dermally in moderate NLFs after 6 months. Secondary objectives included responses at other visits and pain sensation. Treatment-emergent adverse events (TEAEs) were assessed.

Results

A total of 220 subjects were enrolled. The Wrinkle Severity Rating Scale response rates at month 6 were 62.9% for BEL versus 64.9% for RES, demonstrating noninferiority. The secondary endpoints supported this. Significantly reduced pain scores were observed for BEL versus RES. For both products, injection site nodule and bruising were the most frequent treatment-emergent adverse events at the injection site. All treatment-related treatment-emergent adverse events were mild.

Conclusions

The study showed that BEL is effective and well tolerated for correction of moderate NLFs in Chinese subjects. Noninferiority of BEL was demonstrated compared with RES, and regardless of applied pain treatment, a further reduction in injection pain was observed in BEL.

Hyaluronic acid skin penetration evaluated by tape stripping using ELISA kit assay

Hyaluronic Acid (HA) is an endogenous skin matrix component with moisturizing and anti-inflammatory and healing properties. Cosmetic formulations containing HA aim to enhance skin structure, hydrate skin and reduce wrinkles. Therefore, the skin diffusion of HA into stratum corneum after application of a formulation containing two different size of HA, High Molecular weight (HMW-HA) and Low Molecular Weight (LMW-HA)) was evaluated. Ex vivo human skin samples were used to validate an ELISA assay measuring HA in the stratum corneum (SC), viable epidermis and dermis, and to identify optimal washing and extraction methods. These methods were used to measure HA levels in the SC of subjects before and after daily topical application of an HA-containing formulation for 7 days. Samples of SC (5 tape strips) were taken before and 2 h after the application on D0, D1 and D7. The ELISA assay was suitable for measuring HA in the SC but not epidermal or dermal layers. The upper and lower limits of quantitation were the same for both sizes of HA (200 and 3.1 ng/ml, respectively). In both ex vivo human skin and human volunteers, the "dry method" of removing the formulation led to much higher levels of HA in the SC samples, whereas the "wet method" involving one cotton swab soaked with an aqueous solution containing 10% soap and a second cotton swab for drying, was effective in removing the formulation and more relevant to simulate washing/showering. In the clinical study, the amount of HA in SC layers 3-5 were used to represent the HA level in the SC, whereas layers 1 and 2 were considered as surface "residual film". After each application, there was a significantly higher amount of HA compared to the amount before application, which was observed using both wash methods. The residual level 24 h after the first application was at least 8 times higher than before the first application and at least 31 times higher after 7 applications. In conclusion, these investigations validated the use of the ELISA method for the measurement of HA in SC samples. The ex vivo experiments provided recommendations for the clinical study, including the preferred cleansing and optimal sampling methods. The clinical study demonstrated the diffusion, accumulation and maintenance of HA levels in the SC after repeated application of the formulation containing HMW-HA and LMW-HA.

Comparative clinical study for the efficacy and safety of two different hyaluronic acid-based fillers with Tri-Hyal versus Vycross technology: A long-term prospective randomized clinical trial

BACKGROUND

Hyaluronic acid-based fillers have an immediate volumizing effect for the treatment of dermal contour deformities and to smooth dermal depressions formed by the loss of volume. A previous study on 2016-2018 has shown the efficacy and safety of the HA-based filler ART FILLER® Volume on the midface only, but not in a comparative manner.

METHODS

In this context, an 18 months prospective randomized single-blind study of the non-inferiority of ART FILLER® Volume versus the reference product Juvéderm Voluma® was performed on the midface, temple, and jawline, and non-comparative study on the chin. The efficacy and the longevity were evaluated for the selected face areas via dedicated clinical scoring systems after a single filler injection without any re-touch or re-injection. The short- and long-term adverse effects were also recorded.

RESULTS

The observations confirmed the non-inferiority of ART FILLER® Volume versus the reference product on the different injected areas. For both fillers, the beneficial effects on volumes restoration were maintained 18 months post-injection; however, these effects were diminished among the time. Furthermore, injections of Art Filler® Volume were well tolerated by the subjects and showed less acute side effects compared with the reference product that may be explained by a lower induction of inflammation.

An Overview of Maxillofacial Approaches to Smile Design

The oral and maxillofacial surgeon (OMS) has the knowledge and skills to make drastic skeletal changes in favor of a more cosmetic smile. OMS can alter intraoral and extraoral soft tissues to make subtle or significant changes in facial cosmesis. This article provides an overview of the scope of the OMS in smile design. The authors provide a cursory review of pertinent gross and surgical facial anatomy, discuss the role of orthognathic surgery and rhinoplasty in smile cosmesis, and describe the fundamentals of common cosmetic procedures ranging from gingivoplasty to lip lift and lip augmentation and the use of neurotoxins.

An Overview of Soft Tissue Fillers for Cosmetic Dermatology: From Filling to Regenerative Medicine

Hyaluronic acid (HA)-based injectable filling agents are at the forefront of the current demand for noninvasive dermatological procedures for the correction of age-related soft tissue defects. The present review aims to summarize currently available HA-based products and critically appraise their differences in rheological nature and clinical application. Linear HA (LHA) gels may be supplemented with amino acids, lipoic acid, vitamins, nucleosides, or minerals for synergistic antiaging and antioxidant benefits (polycomponent LHA). HA hydrogels can be generated via chemical or physical crosslinking, which increases their elasticity and decreases viscosity. The performance of crosslinked fillers depends on HA concentration, degree of crosslinking, elastic modulus, cohesivity, and type of crosslinking agent employed. PEG-crosslinked LHA displays improved elasticity and resistance to degradation, and lower swelling rates as compared to BDDE-crosslinked LHA. Physical crosslinking stabilizes HA hydrogels without employing exogenous chemical compounds or altering hyaluronans’ natural molecular structure. Thermally stabilized hybrid cooperative HA complexes (HCC) are a formulation of high- and low-molecular-weight (H-HA and L-HA) hyaluronans, achieving high HA concentration, low viscosity with optimal tissue diffusion, and a duration comparable to weakly cross-linked gel. Our critical analysis evidences the importance of understanding different fillers’ properties to assist physicians in selecting the most appropriate filler for specific uses and for predictable and sustainable results.

Monophasic versus biphasic hyaluronic acid filler for correcting nasolabial folds: a systematic review and meta-analysis

BACKGROUND

Hyaluronic acid (HA) fillers are the most popular dermal fillers for wrinkle correction and facial rejuvenation. Recently, there has been an interest toward classifying HA fillers based on the cross-linking properties into monophasic (MHA) and biphasic (BHA) fillers. We aimed to compare the efficacy and safety outcomes between MHA and BHA fillers for the correction of nasolabial folds (NLFs).

METHODS

We searched Medline, Embase, and CENTRAL for randomized controlled trials (RCTs) that compared MHA filler to BHA filler for individuals with moderate-to-severe bilateral NLFs. We sought to evaluate the following outcomes: Wrinkle severity rating scale (WSRS), pain on visual analog scale (VAS), global aesthetic improvement scale (GAIS), and adverse events. The standardized mean difference (SMD) was used to represent continuous outcomes while risk ratio (RR) was used to represent dichotomous outcomes.

RESULTS

A total of 11 RCTs that enrolled 935 participants deemed eligible. MHA filler revealed a significant improvement in the overall WSRS score and GAIS score compared to BHA filler (SMD = -0.38, 95% CI -0.49 to -0.27 and SMD = 0.34, 95% CI 0.24-0.45, respectively). No significant difference was noted between MHA and BHA fillers in terms of pain score or adverse events (SMD = -0.39, 95% CI -0.81-0.03 and RR = 1.00, 95% CI 0.89-1.12, respectively).

CONCLUSIONS

MHA filler showed discernable cosmetic results and comparable effective and tolerability to BHA filler.

Approach to differentiate between hyaluronic acid skin quality boosters and fillers based on their physicochemical properties

BACKGROUND

The clinical indications, applications, and effect of the injectable hyaluronic acid range skin quality boosters (SQBs) are different than those of filler products. Material properties are increasingly being discussed for differentiation and in connection with clinical effects and esthetic indications.

AIMS

The aim of this study is to evaluate whether SQB products can be differentiated from filler products by their physicochemical material properties.

MATERIAL AND METHODS

Physicochemical properties (extrusion force, swelling degree, rheology, and cohesivity) of two SQBs (BEL_R , JUV_VE ) were compared with those of fillers (BEL_B , JUV_VT ) using the same manufacturing technology.

RESULTS

Cohesivity was almost equal for SQBs and fillers. Few statistically significant differences in physicochemical properties were found. Properties of SQBs differed from fillers mainly in their delta of rheological properties and extrusion force.

CONCLUSION

In this study, physicochemical differences between SQB and filler were determined and described, supporting the presence of two categories and their different clinical indications and applications.

Safety of Cohesive Polydensified Matrix Cross-Linked Hyaluronic Acid Volumizing Gel in Temporal Hollows and Cheeks: A Prospective, Open-Label, Postmarket Study

BACKGROUND

Facial aging is characterized by volume loss and progressive hollowing of temples and cheeks. Biodegradable filler materials are preferred over nonabsorbable materials; of these, hyaluronic acid (HA) fillers are the most often used because of their favorable effectiveness and safety profile.

OBJECTIVE

To confirm the safety and effectiveness of Cohesive Polydensified Matrix (CPM)-HA26 gel in the treatment of volume deficiency.

METHODS

Subjects received up to 2 treatments in the temples and/or cheeks. A blinded investigator assessed improvement according to the Merz Temple Volume Scale (MTVS) and Merz Cheek Fullness Assessment Scale (MCFAS). Subjects were followed for 48 weeks after the last treatment.

RESULTS

In total, 87 healthy subjects were enrolled. The proportion of subjects achieving at least a 1-grade improvement on MTVS and/or MCFAS was above 70% for each (MTVS: Weeks 4, 24, and 48 = 95.4%, 94.2%, and 77.0%; MCFAS: Weeks 4, 24, and 48 = 92.3%, 83.1%, and 71.8%). Based on MTVS and MCFAS scores at Visit 5, improvement remained visible at up to 48 weeks. No treatment-related serious AEs occurred.

CONCLUSION

CPM-HA26 demonstrated both a favorable safety and effectiveness profile, with improvement in facial volume evident for up to 48 weeks. It was well tolerated and had a positive, long-lasting effect.

Hyaluronic Acid Is an Effective Dermal Filler for Lip Augmentation: A Meta-Analysis

Introduction: The lips and the mouth play an indispensable role in vocalization, mastication and face aesthetics. Various noxious factors may alter and destruct the original structure, and appearance of the lips and the anatomical area surrounding the mouth. The application of hyaluronic acid (HA) may serve as a safe method for lip regeneration. Although a number of studies exist for HA effectiveness and safety, its beneficial effect is not well-established. Aim: The present meta-analysis and systematic review was performed to investigate the effectiveness of HA on lip augmentation. We also investigated the types and nature of adverse effects (AEs) of HA application. Methods: We reported our meta-analysis in accordance with the PRISMA Statement. PROSPERO protocol registration: CRD42018102899. We performed the systematic literature search in CENTRAL, Embase, and MEDLINE. Randomized controlled trials, cohort studies, case series and case reports were included. The untransformed proportion (random-effects, DerSimonian-Laird method) of responder rate to HA injection was calculated. For treatment related AEs descriptive statistics were used. Results: The systematic literature search yielded 32 eligible records for descriptive statistics and 10 records for quantitative synthesis. The results indicated that the overall estimate of responders (percentage of subjects with increased lip fullness by one point or higher) was 91% (ES = 0.91, 95% CI:0.85-0.96) 2 months after injection. The rate of responders was 74% (ES = 0.74, 95% CI:0.66-0.82) and 46% (ES = 0.46, 95% CI:0.28-0.65) after 6 and 12 months, respectively. We included 1,496 participants for estimating the event rates of AEs. The most frequent treatment-related AEs were tenderness (88.8%), injection site swelling (74.3%) and bruising (39.5%). Rare AEs included foreign body granulomas (0.6%), herpes labialis (0.6%) and angioedema (0.3%). Conclusion: Our meta-analysis revealed that lip augmentation with injectable HA is an efficient method for increasing lip fullness for at least up to 6 months after augmentation. Moreover, we found that most AEs of HA treatment were mild or moderate, but a small number of serious adverse effects were also found. In conclusion, further well-designed RCTs are still needed to make the presently available evidence stronger.

Impact of Minimally Invasive Aesthetic Procedures on the Psychological and Social Dimensions of Health

Background:

The impact on psychosocial health of injectable facial treatments such as hyaluronic acid fillers and botulinum toxin type A remains poorly defined. The aim of this study was to measure changes in psychosocial health following aesthetic intervention with injectables in routine clinical practice using the validated FACE-Q patient-reported outcome measure.

Methods:

This was a prospective assessment of patients presenting at a single center for the first time for aesthetic treatment of the face with injectables in February 2020. Participants completed 3 FACE-Q scales at the baseline and again 2 weeks posttreatment: Psychological Function; Social Function; and Appearance-related Psychosocial Distress.

Results:

Complete data were available for 35 individuals (n = 32 women [91%]; mean age: 45.9 ± 13.8 years). Twenty-nine (83%) were treated with hyaluronic acid filler (mean: 2.3 ± 1.3 syringes), and 12 (34%) received onabotulinumtoxinA (mean: 2.0 ± 0.7 areas of the upper face). There were significant improvements on each FACE-Q scale posttreatment: mean change in Psychological Function score was +12.4 [95% CI: 7.9, 16.9; P < 0.001; standardized effect size by Cohen’s d: 0.93]; mean change in Social Function score was +7.9 (95% CI: 3.3, 12.5; P = 0.001; effect size: 0.50); and mean change in Appearance-related Psychosocial Distress score was –20.9 (95% CI: –27.4, –14.3; P < 0.001; effect size: 1.27).

Conclusions:

Aesthetic treatment with injectables was associated with significant improvements in patient-reported psychological and social functioning and reductions in appearance-related distress. This change underlines the value of these therapies for improving psychosocial health in well-selected patients.

Safety and Performance of Etermis 3 and 4 in Wrinkles/Folds Treatment and Facial Volume Enhancement: A Prospective, Evaluator-Blinded, Open-Label Study

Background

Facial aging is characterized by increased prominence of nasolabial folds (NLFs), marionette lines, and thinning of the lips. Cross-linked hyaluronic acid injection is a very effective method for the temporary correction of these areas.

Objective

To confirm the clinical performance and the safety of Etermis 3 (ET3) and/or Etermis 4 (ET4) in the treatment of moderate and severe wrinkles/folds, as well as lip volume enhancement.

Methods

Subjects were treated in at least two facial areas (NLFs, marionette lines, lips). ET3 was used in facial moderate wrinkles while ET4 was used in severe facial skin volume loss. An optional touch-up 1 month after treatment was possible. A blinded investigator assessed improvement on Merz Aesthetic Scales (MAS). Subjects were followed-up for 12 months after the last treatment.

Results

In total, 154 healthy subjects were enrolled. The proportion of subjects achieving ≥1 score improvement in MAS after treatment was above 60% for ET4 (Month 6/7: NLFs 94.9% and marionette lines 81.4%, p≤0.0004; Month 3/4: lips 63.0%, p=0.39) and ET3 (Month 6/7: marionette lines 79.4%, p=0.0005; Month 3/4: lips 65.5%, p=0.31). Facial improvement was still visible at Month 12/13 for ET4 (NLFs ≥76.6%, marionette lines ≥61%, lips ≥36%) and ET3 (marionette lines ≥50% and lips ≥21.9%). No treatment-related serious AEs occurred. The most frequent AEs were injection-site reactions.

Conclusion

Etermis 3 and Etermis 4 demonstrated good clinical performance and safety for NLFs and marionette lines volume enhancement for up to 12 months. Both products can also be used safely to treat lips for volume augmentation.

A randomized, split-face, double-blind, comparative study of the safety and efficacy of small- and large-particle hyaluronic acid fillers for the treatment of nasolabial folds

BACKGROUND

Injections of hyaluronic acid (HA) for tissue augmentation are one of the most common aesthetic treatments performed worldwide. However, few studies have compared the safety and efficacy of small- and large-particle HA (SP-HA; LP-HA).

AIM

To assess and compare the safety and efficacy of SP-HA and LP-HA for the correction of nasolabial folds (NLFs).

METHODS

A prospective, split-face, triple-blind study design was used. Ten female subjects were recruited. Patients underwent treatment at baseline, an optional touch up at Week 2, and a follow-up visit at Week 4. At weeks 2 and 4, a blinded reviewer assessed the patients using the Global Aesthetic Improvement Scale (GAIS) and Wrinkle Severity Rating Scale (WSRS); and subjects completed the Patient Satisfaction Questionnaire (PSQ). At all visits, 3-dimensional imagery and ultrasonography of patients' NLFs were captured. Adverse events (AEs) were evaluated by the Investigator and recorded by subjects in diaries.

RESULTS

The GAIS response rate, defined as ≥ "improved" from baseline, was between 90 (2 weeks) and 100% (1 month) for SP-HA and was 100% for LP-HA, at both visits. Paired-samples t tests revealed significant differences in the change in WSRS scores between groups, at both visits (P < .01). Differences in the clinical effect and lifting capacity of both products were observed in 3-dimensional imagery and ultrasonography. Treatment volumes varied, with 61.32% more SP-HA being required than LP-HA for achieving a ≥ one-grade WSRS improvement. There were no severe AEs throughout the trial, nor AEs related to the investigational device.

CONCLUSIONS

LP-HA demonstrates better efficacy for correcting bony resorption in the nasal pyriform region.

Two Randomized Controlled Trials of Hyaluronic Acid Fillers for the Correction of Nasolabial Folds

YVOIRE Classic s (YC) and Restylane (RES) have similar rheological properties, which suit mid-dermis injection, while the rheological properties of YVOIRE Volume s (YV) are comparable to those of Perlane (PER), which suit deep dermis injection to treat deep wrinkles. Two similarly designed studies aimed to evaluate the performance and safety of YC and YV injected into the nasolabial folds (NLFs).

METHODS

These were split-face designed, evaluator-blind, noninferiority studies. Fifty-eight subjects with moderate-to-severe NLFs were enrolled in the first study and treated with YC and RES, and 57 subjects were enrolled in the second study and treated with YV and PER. The Wrinkle Severity Rating Scale ranged from 1 (no visible fold) to 5 (extremely deep and long folds), and subject satisfaction was evaluated.

RESULTS

The least squares mean Wrinkle Severity Rating Scale scores (standard error) at week 26 were 2.56 (0.09) for both YC- and RES-treated NLFs and 2.89 (0.08) and 2.91 (0.08) for YV- and PER-treated NLFs, respectively. The difference between the groups was 0 and 0.02, and the lower limit of its 95% confidence interval was -0.0725 and -0.0125, which was greater than the predefined margin (-0.29), proving the noninferiority of YC and YV to RES and PER, respectively. The safety profiles and subject satisfaction of YC and YV were similar to those of RES and PER, respectively.

CONCLUSION

YC is comparable to RES and YV is comparable to PER in terms of performance and safety profiles, with NLF-correcting effects lasting for up to 26 weeks.

A Sensitive Chromatographic Method for Hyaluronate Quantification Applied to Analyze the Desorption Behavior on Contact Lenses

Background:

Sodium hyaluronate (NaHA) is generally supplemented in products related to contact lenses for increasing comfort during wearing. The quantity of sodium hyaluronate and the material of lenses affect the retention of sodium hyaluronate on the contact lenses.

Methods:

We developed a convenient and sensitive but unconventional chromatographic method to quantify sodium hyaluronate and analyze its release behavior from contact lenses. The reverse-phase chromatography eluted sodium hyaluronate with high molecular masses in the shortest time and could separate salt and small compounds from sodium hyaluronate.

Results:

This method could accurately quantify sodium hyaluronate with diverse molecular sizes. Because sodium hyaluronate was eluted in a narrow time frame, sensitivity was significantly enhanced, and the limit of detection of this method was 0.45 μg/mL. According to this quantitation method, the attached quantity of sodium hyaluronate is related to the water content of the material. Furthermore, a material test indicated that the release efficiency of sodium hyaluronate depends on the material of lenses. Nonionic Polymacon had a longer half-life in the sodium hyaluronate release curve than negative Methafilcon A and silicone hydrogel.

Conclusion:

This hyaluronate quantification method is a fast, sensitive and accurate method, making it suitable for the in vitro hyaluronate research without further derivatization.

A Randomized, Active-Controlled, 52-Week Study of Hyaluronic Acid Fillers for Anteromedial Malar Region Augmentation

Supplemental Digital Content is available in the text.

Background:

Hyaluronic acid (HA) fillers for volume augmentation in the anteromedial malar region of Asians have been popular for many years. However, studies on their long-term effectiveness are lacking. This study aimed to evaluate the effectiveness and safety of HA fillers injected into the anteromedial malar region for volume augmentation for up to 52 weeks.

Methods:

Each anteromedial malar region of the subjects was treated with YVOIRE Contour (YVO_C) in one side and Restylane Sub-Q (RES_S) in the other and followed up at weeks 2, 14, 26, and 52. The volume using the mid-face aesthetic scale (MFAS) ranging from 0 (full) to 4 (very severely sunken) and the subject’s satisfaction and adverse events were evaluated.

Results:

Total 83 subjects were randomized and treated with YVO_C and RES_S. The LS means (standard error) of MFAS score in the YVO_C and RES_S groups were both 2.56 (0.05) at baseline, 1.32 (0.07) and 1.39 (0.07) at week 26, and 1.84 (0.10) and 1.89 (0.10) at week 52, respectively. The difference in the LS mean of MFAS score between the groups at week 26 was 0.07 (95% confidence interval, 0.01–0.12), showing the non-inferiority of YVO_C to RES_S. About 70% of subjects were still satisfied with the results at week 52. No specific safety concern was detected.

Conclusions:

The HA fillers injected for the anteromedial malar augmentation maintained the volume well for up to 52 weeks. Additionally, both YVO_C and RES_S show similar effectiveness and safety profiles.

Biocompatibility and structural characterization of glycosaminoglycans isolated from heads of silver-banded whiting (Sillago argentifasciata Martin & Montalban 1935)

Glycosaminoglycans (GAGs) were extracted from heads of silver-banded whiting (SBW) fish and subjected to preliminary biocompatibility testing per ISO 10993: intracutaneous irritation, maximization sensitization, systemic toxicity, and cytotoxicity. When the GAG solution was injected intradermally, the observed irritation was within ISO limits and comparable to a marketed control. There was no evidence of sensitization, systemic toxicity, or cellular toxicity on the test organisms treated with the GAG mixture from SBW fish heads. Fractionation by size-exclusion chromatography has shown three distinct fractions: F1 as low molecular weight hyaluronic acid (190 kDa), F2 (82 kDa) and F3 (64 kDa), both as chondroitin sulfates. Structural characterization by 1D and 2D nuclear magnetic resonance spectroscopy and disaccharide analysis have shown sulfation ratios at positions C4:C6 of the F2 and F3 fractions respectively as 70:20% and 50:30%, and the balance of non-sulfated and 4,6-di-sulfated units. The preliminary results here suggest that GAG-based extracts from SBW fish heads are suitable alternative products to be used in soft tissue augmentation, although further long-term biocompatibility studies are still required.

Psychological Analysis of Non-surgical Rhinoplasty

The aim of this study is to analyze the psychological outcomes for patients undergoing non-surgical correction of nasal defects using injections of cross-linked hyaluronic acid. We assessed changes in the subjective perception of nasal appearance after non-surgical rhinoplasty using the Rhinoplasty Outcomes Evaluation (ROE) questionnaire, which is validated and widely used in the literature. One hundred adult subjects without prior history of surgical or non-surgical rhinoplasty underwent non-surgical recontouring using the hyaluronic acid filler from December 2016 to December 2018. The points of inoculation have been standardized by the authors and are divided according to the aesthetic subunits of the nose. A final 74 patients (65 females and 9 males) completed a one-year follow-up and were included in the present study. The ROE questionnaire consists of six questions and assesses the way patients perceive the appearance of their nose and the way they think the people around them view the appearance of their nose. The results of each question were analyzed for each patient, comparing the preoperative results over a 12-month time-frame. Candidates for rhinoplasty, either medical or surgical, are among the most difficult to treat and, interestingly, there is substantial literature showing that among these patients, there is a higher rate of psychiatric disorders. Many of these patients seek aesthetic surgery and are often dissatisfied with the outcome of their surgery. The authors suggest that the use of ROE is not only a valid method of assessing patient satisfaction, but it could also be used as a tool to highlight some of the psychological characteristics of patients long before performing any treatment and could help identify potentially problematic patients.Level of Evidence IV This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

A Comparison of the Efficacy and Safety Between Hyaluronic Acid and Polylactic Acid Filler Injection in Penile Augmentation: A Multicenter, Patient/Evaluator-Blinded, Randomized Trial

BACKGROUND

Studies about the clinical utility of fillers on penile augmentation (PA) are lacking. Furthermore, no randomized study has compared the utilities of fillers.

AIM

To compare the efficacy and safety between hyaluronic acid (HA) and polylactic acid (PLA) filler injection for PA.

METHODS

This prospective, randomized patient/evaluator-blind, comparative multicenter study consisted of an initial 2-week baseline period and 48-week patient/evaluator-blind post-injection period. 72 patients with small penis syndrome were enrolled from 3 institutions between March-July 2016. Patients were divided into 2 groups: the HA group, comprising 36 patients injected with HA, and the PLA group, comprising 36 patients injected with PLA.

MAIN OUTCOME MEASURES

Penile girth and satisfaction were assessed at baseline and at 4, 12, 24, and 48 weeks after injection.

RESULTS

Penile girth increases adequately lasted ≤48 weeks in both groups (16.95 ± 10.53 and 13.49 ± 9.98 mm of mean increase in the HA and PLA groups, respectively; P < .001). The mean penile girth increase in the HA group was significantly greater than that in the PLA group at 4 weeks (P < .001). Subsequently, it gradually decreased and was no longer significantly different at 48 weeks (P = .075). Satisfaction levels increased after injection and were maintained ≤48 weeks. No significant differences were observed in the overall satisfaction level between the groups (P > .05). Filler injection-related adverse events were mild and transient and occurred in 1 and 3 patients in the HA and PLA groups, respectively.

CLINICAL IMPLICATIONS

This study provides an overview of the efficacy and safety of HA and PLA fillers, which are the most commonly used soft tissue fillers for PA.

STRENGTH AND LIMITATIONS

This study, to our knowledge, is the first to compare the efficacy and safety between different filler injections for human PA. However, it was impossible to perform a researcher-blinded trial because of the unique properties of fillers, and 31 patients (43.1%) were dropped during the study period.

CONCLUSIONS

Both HA and PLA filler injections for PA led to a significant augmentative effect without serious adverse events and had clinically comparable efficacy and safety. Yang DY, Ko K, Lee SH, et al. A Comparison of the Efficacy and Safety Between Hyaluronic Acid and Polylactic Acid Filler Injection in Penile Augmentation: A Multicenter, Patient/Evaluator-Blinded, Randomized Trial. J Sex Med 2019;16:577-585.

Treatment of facial lipoatrophy, morphological asymmetry, or debilitating scars with the hyaluronic acid dermal filler Princess® FILLER

PURPOSE

The aim of this study was to evaluate the effectiveness and safety of hyaluronic acid (HA) dermal filler when used in the face for medical reconstructive purposes.

PATIENTS AND METHODS

Adult patients with moderately severe facial lipoatrophy (FLA), morphological asymmetry (MA) of the face, or debilitating scars (DS) on the face were included in a prospective, noncomparative, multicenter, postmarket clinical follow-up study. All patients were treated with an HA filler (Princess® FILLER), which was injected intradermally on study Day 1, with optional touch-up 2 weeks later. The effectiveness of the treatment was evaluated at Weeks 4 and 24, using a six-grade scale ranging from "excellent" to "worsening". The assessments were conducted by both the investigator and the patient and, at Week 4, by the independent photography reviewer as well. Adverse events were collected at each visit.

RESULTS

Fifty-three patients were included in the study (FLA 23, MA 17, and DS 13), and 46 patients completed a 6-month follow-up (FLA 20, MA 15, and DS 11). At Week 4 (primary endpoint), the overall treatment success rate was 100% (FLA), 100% (MA), and 94% (DS), based on assessments made by the investigator, patients, and the independent reviewer, respectively. In most patients (~95%), the effect was sustained over 6 months. Treatment-related adverse events were reported in five patients (9%) and included injection site hematoma, injection site pain, and headache.

CONCLUSION

Dermal filling with HA gel is a viable treatment option for the correction of various deformities of the face resulting from FLA, MA, or DS.

Biocompatibility of injectable hydrogel from decellularized human adipose tissue in vitro and in vivo

Adipose tissue engineering is considered as a promising treatment for repairing soft tissue defects. The decellularized extracellular matrix (ECM) is becoming the research focus in tissue engineering for its tissue specificity. In this study, the human adipose tissue liposucted from healthy people were decellularized by a series of mechanical, chemical, and enzymatic methods. The components of cell and lipid were effectively removed, whereas the collagens and other ingredients in adipose tissue were retained in the human decellularized adipose tissue (hDAT). Then the extracted hDAT was further fabricated into injectable hydrogel, which could be self-assembled to form gel under certain condition. The hDAT hydrogel was nontoxic to human adipose-derived stem cells (ADSCs) and could spontaneously induce adipogenic differentiation in vitro. It was highly biocompatible and could not cause inflammation and rejection after being implanted subcutaneously. The hDAT hydrogel developed in this study will be one of the available choices for soft tissue enlargement and cosmetic fillers because of its noninvasive in collection and implantation process. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1684-1694, 2019.

Successful hyaluronic acid filler injection in a chronic myeloid leukemia patient taking imatinib mesylate

Dermal fillers are highly favored around the globe as minimally invasive or nonsurgical procedures. Imatinib mesylate is the first-line treatment for patients diagnosed with chronic myeloid leukemia. However, some studies describe that imatinib mesylate may increase the tendency of skin fragility which can lead to easy bruising and hyperpigmentation after invasive skin procedures. Yet, to our knowledge, no studies have described any successful dermal filler injection performed on patients who are under imatinib mesylate treatment. Hence, we present a case successfully treated with hyaluronic acid filler injection on a patient under imatinib mesylate treatment. We carefully propose that hyaluronic acid filler can be an effective means of rejuvenation and cosmetic enhancement for those under imatinib mesylate treatment.

Multivalent and multifunctional polysaccharide-based particles for controlled receptor recognition

Polysaccharides represent a versatile class of building blocks that are used in macromolecular design. By choosing the appropriate saccharide block, various physico-chemical and biological properties can be introduced both at the level of the polymer chains and the resulting self-assembled nanostructures. Here, we synthetized amphiphilic diblock copolymers combining a hydrophobic and helical poly(γ-benzyl-L-glutamate) PBLG and two polysaccharides, namely hyaluronic acid (HA) and laminarin (LAM). The copolymers could self-assemble to form particles in water by nanoprecipitation. In addition, hybrid particles containing both HA and LAM in different ratios were obtained by co-nanoprecipitation of the two copolymers. By controlling the self-assembly process, five particle samples with different morphologies and compositions were developed. The interaction between the particles and biologically relevant proteins for HA and LAM, namely CD44 and Dectin-1 respectively, was evaluated by surface plasmon resonance (SPR). We demonstrated that the particle-protein interaction could be modulated by the particle structure and composition. It is therefore suggested that this method based on nanoprecipitation is a practical and versatile way to obtain particles with controllable interactions with proteins, hence with the appropriate biological properties for biomedical applications such as drug delivery.

A novel animal model for residence time evaluation of injectable hyaluronic acid-based fillers using high-frequency ultrasound-based approach

BACKGROUND

Hyaluronic acid (HA)-based devices are among the most popular filler agents for skin rejuvenation. One of the principal goals is the improvement in residence time of HA-based products, to increase their performance and reduce frequency of the treatment. So, understanding fillers, behavior after subcutaneous injection is a fundamental aspect for discovery and optimization of new products. Current in vivo approaches to detect/quantify injected HA fillers are not always well optimized or easy to apply.

OBJECTIVE

To develop more efficacious and noninvasive diagnostic tools to make a quantitative evaluation of the degradation of fillers in a small animal model.

MATERIALS AND METHODS

We evaluated the residence time of different HA-based fillers, fluorescein-labeled and not, injected subcutaneously in mice. Volumes of fillers were monitored through high-frequency ultrasound (HF-US) method while fluorescence intensity through the well-established fluorescence living imaging method. To confirm the effectiveness of HF-US, obtained volumetric measurements were compared with fluorescence intensity values.

RESULTS

Both the presented methods revealed the same degradation kinetics for the tested products.

CONCLUSION

The two used methods are fully comparable and quantitatively accurate. The presented approach has been proved to be noninvasive, sensitive, and reproducible.

Positive Effects against UV-A Induced Damage and Oxidative Stress on an In Vitro Cell Model Using a Hyaluronic Acid Based Formulation Containing Amino Acids, Vitamins, and Minerals

Ultraviolet (UV) radiations are responsible for skin photoaging inducing alteration of the molecular and cellular pathways resulting in dryness and reduction of skin elasticity. In this study, we investigated, in vitro, the antiaging and antioxidant effects of hyaluronan formulations based hydrogel. Skinkò E, an intradermic formulation composed of hyaluronic acid (HA), minerals, amino acids, and vitamins, was compared with the sole HA of the same size. For this purpose, HaCaT cells were subjected to UV-A radiations and H₂O₂ exposure and then treated with growth medium (CTR) combined with M-HA or Skinkò E to evaluate their protective ability against stressful conditions. Cells reparation was evaluated using a scratch in vitro model and Time-Lapse Video Microscopy. A significant protective effect for Skinkò E was shown with respect to M-HA. In addition, Skinkò E increased cell reparation. Therefore, NF-kB, SOD-2, and HO-1 were significantly reduced at the transcriptional and protein level. Interestingly, γ-H2AX and protein damage assay confirmed the protection by hyaluronans tested against oxidative stress. G6pdΔ ES cell line, highly susceptible to oxidative stress, was used as a further cellular model to assess the antioxidant effect of Skinkò E. Western blotting analyses showed that the treatment with this new formulation exerts marked antioxidant action in cells exposed to UV-A and H₂O₂. Thus, the protective and reparative properties of Skinkò E make it an interesting tool to treat skin aging.

Current Therapeutic Strategies for Adipose Tissue Defects/Repair Using Engineered Biomaterials and Biomolecule Formulations

Tissue engineered scaffolds for adipose restoration/repair has significantly evolved in recent years. Patients requiring soft tissue reconstruction, caused by defects or pathology, require biomaterials that will restore void volume with new functional tissue. The gold standard of autologous fat grafting (AFG) is not a reliable option. This review focuses on the latest therapeutic strategies for the treatment of adipose tissue defects using biomolecule formulations and delivery, and specifically engineered biomaterials. Additionally, the clinical need for reliable off-the-shelf therapies, animal models, and challenges facing current technologies are discussed.

Hyaluronic Acid Gel With (HARRL) and Without Lidocaine (HAJU) for the Treatment of Moderate-to-Severe Nasolabial Folds: A Randomized, Evaluator-Blinded, Phase III Study

BACKGROUND

Hyaluronic acid (HA) dermal fillers are frequently used to correct or smooth facial wrinkles and folds such as nasolabial folds.

OBJECTIVE

To compare the efficacy and safety of 2 HA gels, formulated by 2 different manufacturing processes: XpresHAn Technology (HARRL [with lidocaine]) and Hylacross technology (HAJU-a comparator product without lidocaine).

PATIENTS AND METHODS

One hundred seventy subjects with bilateral nasolabial folds rated as moderate or severe, according to the Wrinkle Severity Rating Scale (WSRS), received injections of HARRL in the nasolabial folds on one side of the face and HAJU on the other side. Investigator- and subject-assessed wrinkle severity was measured up to 48 weeks after final injection.

RESULTS

HARRL exhibited a similar safety and efficacy profile compared with HAJU. Noninferiority of HARRL was demonstrated at 24 weeks (WSRS mean change from baseline mean difference -0.1 [95% confidence interval: -0.15, 0.01], p = .090). Incidence of adverse events was 40% for both treatments.

CONCLUSION

HARRL exhibited a similar safety and efficacy profile compared with HAJU.

Cohesive Polydensified Matrix® hyaluronic acid volumizer injected for cheek augmentation has additional positive effect on nasolabial folds

Purpose

Cohesive Polydensified Matrix^® hyaluronic acid (CPM-HA) volumizer has been used successfully for several years to reverse biometric volume loss during facial aging. This observational study explored the additive effect on nasolabial folds when CPM-HA volumizer is injected into the neighboring cheek area.

Patients and methods

In this open-label, prospective, postmarketing noninterventional study, 18 adult patients seeking esthetic enhancement of the lateral cheek hollows and cheekbone area were injected with CPM-HA volumizer integrated with lidocaine (CPM-HA-VL) in the upper or lower cheek area. Safety and performance of CPM-HA-VL up to 12 months after injection with follow-up visits at week 4 and month 3, 6, and 12 were assessed. The primary endpoint was improvement of cheek fullness on the validated Merz Aesthetics Scales. Additionally, changes in nasolabial folds were quantified using a phaseshift rapid in vivo measurement of skin optical three-dimensional (3D) in vivo measurement device.

Results

Patients (94.4% female, median age 52 years, age range 39–69 years) were injected with a mean volume of 2.5±1.1 mL CPM-HA-VL per side. Immediately after injection, mean severity for upper and lower cheek fullness assessed on the validated MAS improved from 2.5±0.6 and 2.8±0.5, respectively, to 1.0±0.0, and remained unchanged through month 12. Improvement in relation to baseline was attested on the Global Aesthetics Improvement Scale for all assessments. Compared with baseline, the following assessments offered a statistical significance in the reduction of wrinkle depth of nasolabial folds (maximum depth reduction by 30.4% at 3 months) according to optical 3D in vivo measurements. Pain during injection was minimal and abated within 30 minutes. Treatment was well tolerated and led to great patient satisfaction.

Conclusion

CPM-HA-VL injected into the upper and lower cheeks led to long-lasting satisfactory cosmetic results in cheek augmentation as well as in reducing depth of nasolabial folds adjacent to the injection site.

In vitro effects of hyaluronic acid on human periodontal ligament cells

Background

Hyaluronic acid (HA) has been reported to have a positive effect on periodontal wound healing following nonsurgical and surgical therapy. However, to date, a few basic in vitro studies have been reported to investigating the potential of HA on human periodontal ligament (PDL) cell regeneration. Therefore, the aim of this study was to investigate the effect of HA on PDL cell compatibility, proliferation, and differentiation in vitro.

Methods

Either non-cross-linked (HA_ncl) or cross-linked (HA_cl) HA was investigated. Human PDL cells were seeded in 7 conditions as follows (1) Control tissue culture plastic (TCP) (2) dilution of HA_ncl (1:100), (3) dilution of HA_ncl (1:10), 4) HA_ncl directly coated onto TCP, (5) dilution of HA_cl (1:100), 6) dilution of HA_cl (1:10) and (7) HA_cl directly coated onto TCP. Samples were then investigated for cell viability using a live/dead assay, an inflammatory reaction using real-time PCR and ELISA for MMP2, IL-1 and cell proliferation via an MTS assay. Furthermore, the osteogenic potential of PDL cells was assessed by alkaline phosphatase(ALP) activity, collagen1(COL1) and osteocalcin(OCN) immunostaining, alizarin red staining, and real-time PCR for genes encoding Runx2, COL1, ALP, and OCN.

Results

Both HA_ncl and HA_cl showed high PDL cell viability (greater than 90%) irrespective of the culturing conditions. Furthermore, no significant difference in both mRNA and protein levels of proinflammatory cytokines, including MMP2 and IL-1 expression was observed. Both diluted HA_ncl and HA_cl significantly increased cell numbers compared to the controlled TCP samples at 3 and 5 days. HA_ncl and HA_cl in standard cell growth media significantly decreased ALP staining, COL1 immunostaining and down-regulated early osteogenic differentiation, including Runx2, COL1, and OCN mRNA levels when compared to control samples. When osteogenic differentiation medium (ODM) was added, interestingly, the expression of early osteogenic markers increased by demonstrating higher levels of COL1 and ALP expression; especially in HA 1:10 diluted condition. Late stage osteogenic markers remained inhibited.

Conclusions

Both non-cross-linked and cross-linked HA maintained high PDL cell viability, increased proliferation, and early osteogenic differentiation. However, HA was consistently associated with a significant decrease in late osteogenic differentiation of primary human PDL cells. Future in vitro and animal research is necessary to further characterize the effect of HA on periodontal regeneration.

Safety and performance of cohesive polydensified matrix hyaluronic acid fillers with lidocaine in the clinical setting - an open-label, multicenter study

Cohesive polydensified matrix (CPM^®) hyaluronic acid fillers are now available with or without lidocaine. The aim of this study was to investigate the safety and performance of CPM^® fillers with lidocaine in the clinical setting. In an open-label, prospective, postmarketing study, 108 patients from seven sites in Germany and Denmark were treated with one or more lidocaine-containing CPM^® fillers. Performance was assessed using the Merz Aesthetics Scales^® (MAS). Pain was rated on an 11-point visual analog scale. Patients’ and physicians’ satisfaction as well as adverse events were recorded. Improvements of ≥1-point on MAS immediately after and 17 days posttreatment were observed in ~90% of patients compared with baseline. All investigators assessed ejection force, product positioning, and performance as similar or superior to the respective nonlidocaine products. Overall, 94% of investigators were satisfied with the esthetic outcomes and were willing to continue using the products. All patients except one were satisfied with the results, and all were willing to repeat the treatment. Mean pain scores were low during (<3.0) and after injection (<0.6). Except for one case of bruising, all adverse events were mild to moderate. CPM^® fillers with lidocaine are safe and effective for a wide range of esthetic facial indications.

A Randomized Clinical Trial to Evaluate the Efficacy and Safety of Lidocaine-Containing Monophasic Hyaluronic Acid Filler for Nasolabial Folds

BACKGROUND

Hyaluronic acid dermal fillers are most frequently used for unwanted wrinkles. Recently, lidocaine has been incorporated into hyaluronic acid fillers to reduce injection discomfort.

METHODS

A randomized, multicenter, double-blind, intraindividual trial was designed to compare a new lidocaine-containing monophasic hyaluronic acid filler (Neuramis Deep Lidocaine) with a lidocaine-containing biphasic hyaluronic acid filler (Restylane Perlane-L) in moderate to severe nasolabial folds. Fifty-eight patients with moderate to severe nasolabial folds were randomized to an injection of Neuramis or Perlane-L in the left or right side of the face. Clinical efficacy and safety were assessed by blinded investigators, independent expert panels, and patients based on the Wrinkle Severity Rating Scale and the Global Aesthetic Improvement Scale at weeks 8, 16, and 24 after the injection.

RESULTS

Wrinkle Severity Rating Scale improvement from baseline with Neuramis (1.64 ± 0.74) was significantly greater than with Perlane-L (1.45 ± 0.54) at week 24 (p < 0.05). The mean Global Aesthetic Improvement Scale score at week 24 was 2.36 ± 0.55 for Neuramis and 2.00 ± 0.50 for Perlane-L (p < 0.05). However, the difference in pain reduction between Neuramis- and Perlane-L-treated sides was not statistically significant.

CONCLUSIONS

The efficacy and safety of Neuramis are comparable to those of Perlane-L in Wrinkle Severity Rating Scale and Global Aesthetic Improvement Scale improvement for the management of nasolabial folds. Furthermore, the difference in pain reduction between the two fillers was not clinically significant.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, I.

The Facial Adipose System: Its Role in Facial Aging and Approaches to Volume Restoration

BACKGROUND

Volume loss in facial adipose tissue plays a critical role in the aesthetics of facial aging. Furthermore, the facial adipose system is a complex network of distinct compartments, and a detailed understanding of these compartments is essential for optimal facial volume restoration.

OBJECTIVE

To review the facial adipose system, age-related changes, and the role of volume restoration products for facial rejuvenation.

METHODS

Publications including deceased donors' dissection studies and more recent studies using computed tomography were reviewed to provide an up-to-date understanding of the facial adipose system anatomy and age-related changes. Current volume restoration treatment options including hyaluronic acid, calcium hydroxylapatite, and poly-L-lactic acid are discussed.

RESULTS

Facial aging is associated with volume loss in superficial and deep adipose compartments, including those of the forehead, cheek, lip, chin, and jowl areas. Volume restoration products can be used to address the age-related changes of the facial adipose compartments.

CONCLUSION

Understanding the complex network of facial adipose compartments and their age-related changes allows for the optimal use of injectable volume restoration products for facial rejuvenation that can be customized to the anatomical needs of each patient.

Hyaluronan: More than just a wrinkle filler

Dermatology is a field that strives not only to alleviate skin disease (therapeutics) but also to improve the perception of wellness (cosmetics). Thus, in this special issue of Glycobiology, it seems appropriate to discuss the biology of a glycosaminoglycan, called hyaluronic acid (hyaluronan, or HA), that has become the most popular agent today for intradermal injections to improve wrinkles and other cosmetic defects. HA is a simple linear polymer in which a simple disaccharide is repeated thousands of time, thereby creating a huge hydrophilic molecule that confers a large volume of hydration and contributes to the turgor and flexibility of healthy skin. Beyond cosmetic considerations, however, HA also has important biological and physiological functions that were largely under-appreciated until recently. New research has confirmed that HA is dynamically produced by most skin cells, not only fibroblasts (the cells that make most of the skin's extracellular matrix) but also by keratinocytes in the outer protective layer (epidermis). For both fibroblasts and keratinocytes, HA plays a regulatory role in controlling cell physiology through interaction of extracellular HA with a major cell-surface receptor, CD44. This interaction mediates intracellular signaling both directly and indirectly, through CD44 interactions with the cytoskeleton and with EGF and TGFβ receptors. Furthermore, degradation of HA by specific hyaluronidase enzymes produces HA fragments that can help to regulate inflammatory processes. In this review, current knowledge about the role of HA in skin inflammation and wound healing are reviewed and possible future applications of such knowledge discussed.

Introduction to Fillers

BACKGROUND

Over the last few years, injectable soft-tissue fillers have become an integral part of cosmetic therapy, with a wide array of products designed to fill lines and folds and revolumize the face.

METHODS

This review describes cosmetic fillers currently approved by the Food and Drug Administration and discusses new agents under investigation for use in the United States.

RESULTS

Because of product refinements over the last few years-greater ease of use and longevity, the flexibility of multiple formulations within one line of products, and the ability to reverse poor clinical outcomes-practitioners have gravitated toward the use of biodegradable agents that stimulate neocollagenesis for sustained aesthetic improvements lasting up to a year or more with minimal side effects. Permanent implants provide long-lasting results but are associated with greater potential risk of complications and require the skilled hand of the experienced injector.

CONCLUSIONS

A variety of biodegradable and nonbiodegradable filling agents are available or under investigation in the United States. Choice of product depends on injector preference and the area to be filled. Although permanent agents offer significant clinical benefits, modern biodegradable fillers are durable and often reversible in the event of adverse effects.

The Efficacy and Safety of Lidocaine-Containing Hyaluronic Acid Dermal Filler for Treatment of Nasolabial Folds: A Multicenter, Randomized Clinical Study

BACKGROUND

The use of injectable hyaluronic acid-based gel is well established in aesthetic facial procedures especially on the nasolabial fold (NLF).

OBJECTIVE

To compare the efficacy and safety of PP-501-A-Lidocaine dermal filler with RestylaneLidocaine(®) when administered to the NLF.

METHODS

Sixty-six subjects seeking correction of NLFs, with moderate or severe wrinkle severity, were recruited for this multicenter, randomized, patient and evaluator-blind, matched pairs, and active-controlled design clinical study. PP-501-A-Lidocaine and RestylaneLidocaine(®) were injected into the deep layer of the dermis and/or subcutis of the NLF. The first validity evaluation variable was the average wrinkle severity rating scale (WSRS), as scored by independent blinded evaluators at week 24. The second validity evaluation variable including the global aesthetic improvement scale (GAIS), the WSRS, and adverse event reporting at weeks 8, 16, and 24 were also performed.

RESULTS

The mean improvement in the WSRS from baseline was 1.58 ± 0.68 for the PP-501-A-Lidocaine and 1.51 ± 0.66 for the RestylaneLidocaine(®) at week 24. The average value at week 8 after the final application was 1.62 ± 0.78 and 1.60 ± 0.75 in parts subject to PP-501-A-Lidocaine and RestylaneLidocaine(®), respectively, and 1.58 ± 0.70 and 1.57 ± 0.68 at week 16, respectively. Both improvement and duration of the treatment effect were similar between the two groups. GAIS data rated by the treating investigator and participants showed no statistically significant differences. Both fillers were well tolerated and adverse reactions were mild and transient in most cases.

CONCLUSION

PP-501-A-Lidocaine showed an equivalent efficacy and safety observed after 6 months of follow-up compared to RestylaneLidocaine(®).

LEVEL OF EVIDENCE I

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to Table of Contents or the online Instructions to Authors www.springer.com/00266.

Dermal fillers: an update

Injection of dermal fillers is the second most frequent nonsurgical cosmetic procedure performed in the USA. Dermal fillers are an option in the treatment of volume deficiency, scars, and rhytides; facial sculpting; facial contouring; and augmentation of specific anatomical sites such as the lips. The number of injectable dermal fillers available on the market increases yearly. Dermatologists and cosmetic surgeons should regularly review treatment options to provide patients with safe and effective filler options. This paper extensively reviews the properties of the available fillers, such as their rheology, longevity, and adverse effects, and how these properties affect the choice of filler agent for a particular patient or a particular site. Also, trends in dermal filler injections are discussed.