Recommendations for volume augmentation and rejuvenation of the face and hands with the new generation polycaprolactone-based collagen stimulator (Ellansé®)

Investigating Facial Muscle Physiology Following Soft Tissue Filler Injections-A Surface-derived Electromyographic and Skin Vector Displacement Analytic Study

The use of hyaluronic acid-based soft tissue fillers has often been reported to modulate the muscle, that is, to cause myomodulation. To our knowledge, there has been so far no scientific study investigating the potential of hyaluronic acid-based soft tissue fillers to modulate or actually alter the function of facial muscles. To further assess this three-dimensional (3D) surface imaging and electromyography (EMG)-based prospective study investigated the changes of facial muscle contraction after injection of strategically placed hyaluronic acid-based soft tissue fillers to assess the actual validity of the term myomodulation. A total of 13 subjects with a mean age of 37.8 years (12 females, 1 male) were injected according to a predefined injection protocol. Surface EMG and 3D surface imaging were performed prior to the injection and 5 days after the injection. The results showed no significant change in the strength of the muscles (measured in μV) after injection of hyaluronic acid-based soft tissue fillers. However, horizontal and vertical skin displacement upon contraction of the zygomaticus major muscle changed significantly between baseline and follow-up, with a mean horizontal skin displacement increase from 3.2 to 4.1 mm. Upon contraction of the depressor anguli oris muscle, the horizontal skin displacement did not change significantly (2.15 vs. 2.05 mm), while vertical skin displacement increased significantly from 2.9 to 4.3 mm. The modification of the surrounding tissue caused an alteration of the vectorial skin displacement upon contraction of the muscle. A potential explanation could be the increased distance between the origin and insertion of the muscle due to the material deposition in the proximity of the relevant facial muscles, leading to a change of contraction vector.

Ellansé: Advanced Technology and Advantageous Selection of New Collagen Stimulating Agents for Face Rejuvenation

Facial injections have a comparative mature market and system in China, but all kinds of injection materials have their own advantages and disadvantages, even hyaluronic acid, as the most common injection material, can form an unnatural stiffness after injection. Currently, Ellansé, a biodegradable collagen stimulator, has shown superior aesthetic results while ensuring safety and naturalness, making it a more preferable choice for a variety of facial injections. The purpose of this review is to introduce the features and benefits of Ellansé, so that doctors in the field can better understand and learn how to use it properly and minimize the risk of complications, and have a better choice for the medical aesthetic field in China in numerous aspects. The papers with the keyword "Ellansé" is very few in number, and there is a lack of systematic overview. Ellansé itself has unique advantages for the Chinese population, as it is an attractive option for the treatment of aging face due to high patient satisfaction, long-lasting results and low side effects (Guo et al. in J Cosmet Dermatol 21(5):1959-1966, 2022). More clinical data will be available in the future to confirm its performance and longevity in various sites. LEVEL OF EVIDENCE V: 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 .

Body Harmonization: The Definition of a New Concept

Body Harmonization (BHA) is an innovative concept in aesthetics area based on a set of advanced injectable techniques that have shown promising results for body shaping. This is based on procedure combinations indicated to treat body aesthetic dysfunctions, such as localized fat, stretch marks, blemishes, flaccidity, buttocks remodeling, lean mass gain and muscle definition. This study aims to define the clinical concept of BHA, its applications and the main protocols used based on injectable pharmacotherapy. For this purpose, we performed a retrospective review of proven efficient injectable procedures with advanced results for the treatment of body aesthetic disorders, in addition to relying on data obtained from previous clinical experiences. Based on these data, we describe how different compounds can act for treatment of the main body aesthetic dysfunctions, such as lipolytic compounds and collagen biostimulators. In addition, the main application techniques and treatment protocols for each of these dysfunctions were defined. Minimally invasive injectable procedures offer an effective therapeutic option for patients who do not intend to undergo surgical interventions.

Decades of beauty: Achieving aesthetic goals throughout the lifespan

BACKGROUND

Several elements, including age, influence judgments of beauty and attractiveness. Aging is affected by intrinsic factors (e.g., genetics, race/ethnicity, anatomical variations) and extrinsic factors (e.g., lifestyle, environment).

AIMS

To provide a general overview of minimally invasive injectable procedures for facial beautification and rejuvenation to meet the aesthetic goals of patients across their lifespan, organized by decade.

METHODS

This case study review describes aesthetic considerations of females in their third to sixth decade of life (i.e., 20-60 years of age or beyond). Each case study reports the treatments, specifically botulinum toxin type A and soft tissue fillers, used to address aesthetic concerns.

RESULTS

Signs of aging, as well as aesthetic goals and motivations, vary by age groups, cultures, and races/ethnicities. However, there are overarching themes that are associated with each decade of life, such as changes in overall facial shape and specific facial regions, which can be used as a starting point for aesthetic treatment planning. Appropriate patient selection, thorough aesthetic evaluation, product knowledge, and injection technique, as well as good physician-patient communication, are essential for optimal treatment outcomes.

CONCLUSIONS

Nonsurgical facial injectable treatments can successfully enhance and rejuvenate facial features across different age ranges. A comprehensive understanding of facial aging and the aesthetic considerations of patients by the decade contributes to optimal treatment planning and maintenance.

Objective Assessment of the Long-Term Volumizing Action of a Polycaprolactone-Based Filler

Background

The polycaprolactone-based filler, (PCL-1, Ellansé-S), forms part of the recently growing portfolio of biodegradable collagen-stimulating fillers. It is comprised of a suspension of 25-50 micron diameter microspheres of polycaprolactone (PCL) (30%) in a carboxymethyl cellulose (CMC) gel carrier (70%) and has gained popularity due to its long-term volumizing action.

Objective

This study outlines a retrospective case series of nine patients injected with the PCL-1, for volume augmentation in the mid-face. Objective volume calculations were performed with the Canfield Vectra 3D Imaging System at two time points post-implantation, with the objective of determining the longevity of the volumizing effect of the bio-stimulating substance.

Results

A clear increase in volume, between 50-150%, was found in all of the patients at two years, over and above the volume initially injected. All the patients were satisfied with the longevity of the results.

Discussion

The PCL-based filler is believed to afford immediate volume restoration due to the CMC gel component and a long-term action due to neo-collagenesis, induced by the PCL microspheres. The CMC gel is known to dissipate within 6-8 weeks, only to be replaced by new collagen induced by the PCL particles. Thus soft-tissue formation induced by the PCL particles, ultimately leads to a sustained volumizing effect.

Conclusion

The PCL-based filler is shown to have a sustained volumizing effects of at least 2 years duration with clear evidence of increase in volume over and above the volume injected, in all of the cases studied. This is indicative of significant neo-collagenesis induced by the PCL microspheres.

Efficacy and Safety of Polycaprolactone in Treating Nasolabial Folds: A Prospective, Multicenter, and Randomized Controlled Trial

Nasolabial folds (NLFs) are the most pronounced sign of facial aging. This study explored the efficacy and safety of polycaprolactone gel in treating Chinese patients with moderate-to-severe NLFs. Patients with moderate-to-severe NLF who wished to be treated by dermal fillers were recruited from three centers between July 2017 and September 2019. The randomizing ratio was 1:1 in the polycaprolactone group (polycaprolactone injection) or control group (sodium hyaluronate gel injection). The primary endpoint was the effectiveness rate of Wrinkle Severity Rating Score (WSRS) scores at 12 months after injection. The full-analysis set (FAS) and safety sets had 80 patients in the polycaprolactone group and control group, respectively. In the FAS, the effectiveness rate at 12 months in the polycaprolactone group was 88.8% compared with 23.8% in controls (P < 0.001). The improvement in WSRS sustained during 12 months in the polycaprolactone group, while gradually vanished in the control group since 3 months after surgery. The global aesthetic improvement scale (GAIS) by investigator assessments was improved, much improved, or very much improved in all patients during follow-up, while the proportion of patients with a "no change" assessment gradually increased during follow-up after 6 months in the control group. The rates of injection-related adverse event (AE) and serve injection-related AE were 8.8 versus 11.3% and 0 versus 1.3% in the polycaprolactone group and control groups, respectively. Polycaprolactone gel injection is effective and safe to treat moderate-to-severe NLFs in Chinese patients.

Collagen Stimulators in Body Applications: A Review Focused on Poly-L-Lactic Acid (PLLA)

The number of aesthetic procedures performed worldwide continues to grow together with an increase in the population seeking the restoration or preservation of a youthful appearance. Requests for non-surgical body rejuvenation are increasing. Patients are looking for safe and effective minimally invasive aesthetic procedures. Soft-tissue dermal fillers can meet these expectations. Based on the beneficial outcomes of these treatments in many facial areas, a new trend is developing to target body areas. Different dermal fillers are available and include collagen stimulators initially developed to restore facial volume. Furthermore, they are associated with long-lasting efficiency, a high level of patient satisfaction and a good safety profile, with mainly minor adverse events reported. In appropriate conditions of use, they are now used for body rejuvenation in clinical practice. Their use is expanding and allows addressing various issues including volume loss, skin laxity, cellulite, striae distensae and wrinkles. This review focuses on poly-L-lactic acid (PLLA), used in the first collagen stimulator and one of the most investigated in facial and in off-facial body applications. The available published data, although still limited, are presented by body area, neck and chest, buttocks, abdomen, upper arms, thighs, knees, and hands. Key features of the concerned zones and the main clinical signs affecting the body part as well as the injection modalities are provided along with the aesthetic results. This represents the state of the art on which to base further developments necessary for optimal and safe outcomes of treatment with the PLLA-based collagen stimulators and others in this class for body rejuvenation.

A randomized, participant-and evaluator-blinded, matched-pair prospective study to compare the safety and efficacy between polycaprolactone-based fillers in the correction of nasolabial folds

BACKGROUND

Polycaprolactone (PCL)-based fillers are widely used for skin rejuvenation and wrinkle reduction.

OBJECTIVE

To compare the efficacy and safety of newly developed PCL-based fillers (SYB filler®; SF-01) and widely used existing PCL-based fillers (Ellansé-M®) for correction of moderate-to-severe nasolabial folds.

METHODS

In a randomized, participant-and evaluator-blinded, matched-pair, prospective study, participants were randomized for injections of SF-01 or Ellansé-M® in both nasolabial folds. Efficacy was evaluated using the Wrinkle Severity Rating Scale (WSRS), Global Esthetic Improvement Scale (GAIS), and a 3-dimensional (3D) scanner. All adverse events (AEs) were examined and reported.

RESULTS

At month 12, both SF-01-and Ellansé-M®-treated groups showed statistically significant improvements in the WSRS, GAIS, and 3D scanner scores compared to baseline. The difference in changes in WSRS scores at month 12 between the two groups was 0.08 ± 0.34 compared to baseline. The upper limit of the 95.0% confidence interval was 0.0031, which was lower than the predefined margin for non-inferiority (0.35). All AEs were injection site-related (swelling, pain, and erythema) and disappeared within 30 min after the procedure.

CONCLUSION

SF-01 was non-inferior to Ellansé-M® and demonstrated favorable efficacy and safety at 12 months after correcting moderate-to-severe nasolabial folds.

Natural Fiber-Reinforced Polycaprolactone Green and Hybrid Biocomposites for Various Advanced Applications

Recent developments within the topic of biomaterials has taken hold of researchers due to the mounting concern of current environmental pollution as well as scarcity resources. Amongst all compatible biomaterials, polycaprolactone (PCL) is deemed to be a great potential biomaterial, especially to the tissue engineering sector, due to its advantages, including its biocompatibility and low bioactivity exhibition. The commercialization of PCL is deemed as infant technology despite of all its advantages. This contributed to the disadvantages of PCL, including expensive, toxic, and complex. Therefore, the shift towards the utilization of PCL as an alternative biomaterial in the development of biocomposites has been exponentially increased in recent years. PCL-based biocomposites are unique and versatile technology equipped with several importance features. In addition, the understanding on the properties of PCL and its blend is vital as it is influenced by the application of biocomposites. The superior characteristics of PCL-based green and hybrid biocomposites has expanded their applications, such as in the biomedical field, as well as in tissue engineering and medical implants. Thus, this review is aimed to critically discuss the characteristics of PCL-based biocomposites, which cover each mechanical and thermal properties and their importance towards several applications. The emergence of nanomaterials as reinforcement agent in PCL-based biocomposites was also a tackled issue within this review. On the whole, recent developments of PCL as a potential biomaterial in recent applications is reviewed.

Bioactive PCL microspheres with enhanced biocompatibility and collagen production for functional hyaluronic acid dermal fillers

Polymeric microspheres containing magnesium hydroxide (MH) and a bioactive agent (BA), such as apocynin (APO) and astaxanthin (ATX), have been prepared as functional dermal fillers with enhanced physicochemical and biological performance.

L-Lift Technique Using Poly-l-Lactic Acid: A Pilot Study

BACKGROUND

Minimally invasive procedures that prevent and delay the aging process can be an alternative to more invasive surgical procedures.

OBJECTIVE

To assess the efficacy and safety of L-Lift technique to improve skin firmness, facial global aesthetics, and the patient and investigator satisfaction.

METHODS

Prospective, open, single-center study. Thirty participants underwent 3 treatment sessions 1 month apart and were assessed 8, 16, and 24 weeks after first injections. Assessments included the Facial Laxity Rating Scale (FLRS), Global Aesthetic Improvement Scale (GAIS), objective measurement of skin elasticity, and the Skin Distension Test.

RESULTS

At Week 24, 60% of the patients had at least 1-class improvement in the FLRS for the middle face and 33% for the lower face. At Week 24, investigators considered that 90.0% of the patients improved according to the GAIS and 90.0% of the subjects considered they have improved. Skin elasticity (at Week 8 and at Week 16) and Skin Distension Test (at Week 24) assessments indicated improvement in skin firmness. Both patients and investigators were satisfied with the treatment at the study end.

CONCLUSION

The technique is safe and efficacious. It may be particularly suitable for patients presenting initial signs of facial skin laxity.

European Multicenter Prospective Study Evaluating Long-Term Safety and Efficacy of the Polycaprolactone-Based Dermal Filler in Nasolabial Fold Correction

BACKGROUND

Age-related changes affecting facial areas can be corrected using minimally invasive dermal fillers. The use of polycaprolactone-dermal filler (PCL-filler) in aesthetics is increasing.

OBJECTIVE

To evaluate the long-term safety and efficacy of the PCL-filler, in a European, multicenter, prospective study.

MATERIALS AND METHODS

Subjects (n = 90) with moderate/severe nasolabial folds (Wrinkle Severity Rating Scale [WSRS]: 3 to 4) were treated on Day 0 with a single injection of similar volume on each side; safety and efficacy assessments were performed over an 18-month period. In 1 of the 3 study centers, safety was evaluated at 30 months.

RESULTS

At Month 12 (M12; primary endpoint), 84% of subjects showed a ≥1-point improvement on the WSRS (M6: 92%; M18: 64%). From the investigator/subject's evaluation, from Day 7 to M12, Global Aesthetic Improvement was reported for >90% of subjects, with the effect maintained for up to 18 months in >80% of patients. Subjects/investigators reported high satisfaction and skin quality improvement. Most of the immediate injection-site reactions disappeared after 2 to 4 days. No severe or unexpected adverse events were reported.

CONCLUSION

This study demonstrated the long-term safety and efficacy of the PCL-filler, with safety confirmed for up to 30 months.

Polycaprolactone-based dermal filler complications: A retrospective study of 1111 treatments

Background

Aging signs can be corrected through volume restoration in multiple soft tissue layers and in the supraperiosteal plane using hyaluronic acid (HA) or nonhyaluronic acid (non‐HA) fillers. The non‐HA bioresorbable polycaprolactone (PCL)‐based filler with collagen‐stimulating properties has a proven safety profile, but rare potential complications such as nodules and granuloma can occur. Furthermore, PCL‐based fillers cannot be immediately removed by injection of an enzyme. These potential drawbacks have yet to be described in the literature.

Aims

The author performed 1111 treatments between 2015 and 2018. This study aims to review and analyze these treatments to ascertain the complication rates of the PCL‐based filler. Suggestions for complication prevention and management are also discussed.

Methods

780 patients treated with the PCL‐based filler were reviewed by the physician between April 2015 and May 2018. During this period, 5595 syringes were used in 1111 treatments. All complication data were acquired by phone interviews, reports by patients, or observation at follow‐up visits. Complications were subdivided into early‐onset (occurring up to 2 weeks after treatment) and late‐onset events (occurring more than 2 weeks to years after treatment).

Results

Among the 1111 treatments, there were 50 cases (4.5%) of edema that lasted longer than 2 weeks, 30 cases (2.7%) of bruising, 8 cases (0.72%) of malar edema, 5 cases (0.45%) of temporarily palpable lumps and 2 cases (0.18%) of discoloration. There were no cases of intravascular injection, nodules/granulomas, or infection.

Conclusion

The complication rate of the PCL‐based filler was found to be low, and there were no cases of intravascular injection, nodules, and/or granulomas during the 3‐year observation. Longer‐lasting edema was associated with a higher injection volume and malar edema was related to lymphatic compression.

Minimally Invasive Aesthetic Treatment of the Face and Neck Using Combinations of a PCL-Based Collagen Stimulator, PLLA/PLGA Suspension Sutures, and Cross-Linked Hyaluronic Acid

Background

Combinations of minimally invasive procedures (MIPs) are often used in aesthetic treatments and are increasingly considered as the new standard of care. Three agents with specific properties are available in this perspective: a polycaprolactone (PCL)-based collagen stimulator, a poly-L-lactic acid (PLLA)- and a poly-glycolic acid (PLGA)-based resorbable suspension suture with a 3D-cone technology, and a cross-linked hyaluronic acid (HA).

Objective

To develop the first practice guidelines on rejuvenation treatment of the face and the neck using combinations of these agents, whether associated or not with other widely used MIPs such as botulinum neurotoxins or energy-based devices.

Methods

A multi-disciplinary, multi-national board of plastic surgeons and dermatologists convened to develop guidelines using a predefined consensus method. The consensus was defined as ≥83% agreement rate between participants.

Results

Practice guidelines and algorithms, describing optimal procedure sequence and spacing, are proposed for the treatment of upper-, mid-, lower-face and neck, combining the PCL collagen stimulator, the PLLA/PLGA suspension sutures, and the cross-linked HA, whether associated or not with other MIPs.

Conclusion

These new guidelines provide general support to optimal management strategies. Individual treatment plans should be adapted according to the physician’s individual competence and the patient’s preferences.

[Eruptive granuloma after injection of Ellansé® successfully treated using methotrexate]

BACKGROUND

Collagen stimulators such as Ellansé® are soft tissue fillers able to induce nucleogenesis. We describe a case of eruptive foreign body granulomas following injection of Ellansé® that were successfully treated using methotrexate.

CASE REPORT

A 47-year-old woman received injections of Ellansé® for the wrinkled aspect of her cheeks. She had previously undergone injections of hyaluronic acid on the nasolabial folds. Nine months after the Ellansé® injections, the patient consulted for the recent appearance of multiple nodules on her face. Histological analysis of one of these nodules confirmed the presence of foreign-body granulomas developed in contact with spherical gaps of a size substantially identical to the Ellansé® vacuoles. Methotrexate 10mg per week for 3 months followed by 20mg per week for 9 months resulted in complete regression of the nodules.

DISCUSSION

Ellansé® is composed of two biocompatible and bioabsorbable polymers: carboxymethylcellulose, responsible for immediate volume creation, and polycaprolactone, which promotes collagen synthesis. However, any injected product can cause varying degrees of granulomatous reaction. Hyaluronic acid was previously injected at several other sites on the patient's face. These lesions were not the result of poor injection technique.

CONCLUSION

Although collagen stimulators are biocompatible and bioabsorbable substances, the development of foreign-body granulomas, while rare, is still possible. Methotrexate resulted in significant regression of nodules as of the third month of treatment.

Signaling Molecule-Immobilized Porous Particles with a Leaf-Stacked Structure as a Bioactive Filler System

The ultimate purpose of this study was to develop a bioactive filler system that would allow volume restoration (passive property) and continuous release of signaling molecules to recruit soft tissues (bioactive property) and thus effectively correct facial aging. To achieve this, we prepared porous particles with a leaf-stacked structure throughout the entire particle volume (LSS particles) using a simple heating-cooling technique. LSS particles were loaded with insulin-like growth factor-1 (IGF-1) and vascular endothelial growth factor (VEGF) separately, by immersing the particles in signaling molecule-containing solutions for target tissue recruitment (adipose by IGF-1 and blood vessels by VEGF). IGF-1 and VEGF were continuously released from LSS particles for 28 and 21 days in vitro, respectively, even without additional chemical/physical modifications, because of the unique morphology of the particles. Signaling molecules preserved their bioactivity in vitro (induction of adipogenic and angiogenic differentiation) and in vivo (recruitment of fat and blood vessels) for a sufficient period. Moreover, it was observed that the LSS particles themselves have stable volume retention characteristics in the body. Thus, we suggest that the signaling molecule-loaded LSS particles can function as a bioactive filler system for volume retention and target tissue regeneration.

Polycaprolactone: How a Well-Known and Futuristic Polymer Has Become an Innovative Collagen-Stimulator in Esthetics

Compared to other domains, tissue engineering and esthetics have dramatically expanded in recent years, leading to both major biomedical advances and futuristic perspectives. The two share a common approach based on biomaterials, especially polymers. This paper illustrates this with the example of polycaprolactone (PCL), a polymer synthesized in the early 1930s, and one of its most recent applications, a PCL-based collagen stimulator, a filler used in esthetics. PCL is biocompatible and biodegradable. Its specific physicochemical and mechanical properties, viscoelasticity and ease of shaping led to the production of PCL-based products with various shapes and durations dependent on its biodegradation kinetics. PCL has been safely used in the biomedical field for more than 70 years, from sutures to tissue and organ replacement by 3D printing. The PCL-based collagen stimulator is composed of PCL microspheres suspended in a carboxymethyl-cellulose gel carrier providing immediate and sustained volumizing effects when injected; the morphology, the biocompatibility of the PCL microspheres embedded with the collagen fibers produced all contribute to the creation of a unique 3D scaffold for a sustained effect. Its safety has been investigated in clinical studies and vigilance surveys. Recently published experts' recommendations on injection modalities and techniques should help further optimize treatment outcome and safety. This paper also integrates reviews and recommendations on the prevention and management of adverse events related to dermal and subdermal fillers including the PCL-based collagen stimulator. In addition, in terms of efficacy and safety, this product benefits from its daily clinical use in esthetics worldwide and continuous extensive fundamental and clinical research, both on it and the PCL polymer. Forthcoming data from further investigations will reinforce knowledge of the product and procedures in the field.

New Frontiers in Skin Rejuvenation, Including Stem Cells and Autologous Therapies

One of the greatest challenges in the progression of aesthetic medicine lies in providing treatments with long-term results that are also minimally invasive and safe. Keeping up with this demand are developments in autologous therapies such as adipose-derived stem cells, stromal vascular fraction, microfat, nanofat, and platelet therapies, which are being shown to deliver satisfactory results. Innovations in more traditional cosmetic therapies, such as botulinum toxin, fillers, and thread lifts, are even more at the forefront of the advancement in aesthetics. Combining autologous therapies with traditional noninvasive methods can ultimately provide patients with more effective rejuvenation options.

Changes in Dermal Thickness in Biopsy Study of Histologic Findings After a Single Injection of Polycaprolactone-Based Filler into the Dermis

BACKGROUND

During aging, facial skin thins, atrophies, and loses elasticity. Subdermal filler injections can volumize and treat wrinkles but cannot directly change dermal thickness. Polycaprolactone (PCL) fillers can improve skin texture and quality through dermal thickening and inducing neocollagenesis. Through biopsy study, evidence of neocollagenesis will be introduced.

OBJECTIVES

In this single-clinic prospective study, 13 patients received a single injection of diluted 0.5 cc of PCL filler in the facial dermis except the right temple area for intra-individual control study.

METHODS

A biopsy was performed from temple skin at 1 year for all patients. An additional biopsy was performed at 2 weeks and 4 years posttreatment for 3 patients. Dermal thickness was measured with sonography after 1 year.

RESULTS

On average, the mean rate of temporal skin thickness in biopsy specimens (n = 117 points in 13 patients) at 1 year posttreatment increased by 26.74% ± 9.26% from 1412.41 μm ± 69 μm to 1781.11 μm ± 110 μm (P < 0.001). On average, the mean thickness of facial skin (n = 39 points in 13 patients) measured by ultrasound at 1 year increased by 21.31% ± 4.34%. Around PCL particles, many fibroblasts, giant cells, new capillaries, new collagen, and elastic fibers were found in various stains.

CONCLUSIONS

Facial dermal thickness increased after intradermal injection of PCL filler by neocollagenesis to treat skin atrophy. PCL filler may last more than 4 years in the dermis.

LEVEL OF EVIDENCE: 4

Biostimulatory effects of polydioxanone, poly-d, l lactic acid, and polycaprolactone fillers in mouse model

BACKGROUND

Numerous fillers are increasingly used for augmentation of volume loss and relaxation of facial wrinkles. Collagen stimulators are the latest next-generation dermal fillers that can induce neocollagenesis. To investigate biophysical characteristics, safety, and efficacy of newly developed polydioxanone (PDO) filler in comparison with poly-l lactic acid (PLLA) and polycaprolactone (PCL) fillers.

METHODS

In vitro assay, morphology of particles, and rheological property of fillers were measured. A total of 24 female hairless mice (SKH1-Hr^hr ) were randomly divided into three groups and injected with PDO, PLLA, or PCL fillers. Durability of fillers was assessed at 0, 3 days, and 1, 4, 8, 12 weeks after injection using folliscope and PRIMOS. To determine biocompatibility and neocollagenesis, histologic evaluation was performed at 1, 4, 8, and 12 weeks after injection. Efficacy was also evaluated based on skin surface roughness changes using PRIMOS in a hairless mouse photoaging model.

RESULTS

In the particle morphology test, PDO microspheres had an irregular surface and were spherical and uniformly sized. PDO filler demonstrated similar neocollagenesis and inflammatory response to other collagen stimulators. PDO filler showed better biodegradability than PLLA and PCL fillers. In the hairless mouse photoaging model, there was a statistically significant decrease in skin surface roughness after PDO filler injection.

CONCLUSIONS

Our data suggest that newly developed collagen stimulating PDO filler might be a safe and effective option for correction of volume loss and rejuvenation of photoaging skin.

Adverse effects of fillers

Filler injections belong to the most frequently performed noninvasive beautifying procedures. When done correctly they are generally well tolerated. However, a number of factors, such as poor filler quality, and particularly host as well as user dependent filler reactions may lead to unwanted effects. These may be early, late, or delayed events with characteristics for each of them. Temporary fillers almost invariably cause temporary side effects whereas those of permanent fillers may last forever. Some fillers are notorious for their poor safety profile; for example, silicone is banned in the European Union and the United States but nevertheless used by many practitioners and beauticians. Many fillers can be identified in histopathologic sections allowing specific measures to be instituted.

Granuloma as a complication of polycaprolactone-based dermal filler injection: ultrasound and histopathology studies

In aesthetic medicine, there has been an ongoing search for an ideal dermal filler to offer zero complication rate. Polycaprolactone-based dermal filler (PCL) has been available since 2009. The purpose of the paper was to present a case of granuloma as a complication of PCL injection, which has not been reported so far by other researchers. A 68-year-old female was injected with PCL. One year later, nodules accompanied by bluish skin discoloration developed within the injection site. Ultrasound and histopathology studies were performed. The examinations confirmed the presence of foreign body granuloma after PCL, which makes it the first reported case worldwide. The published data analyses showed general lack of studies and case reports to address this issue. The PCL, like an injection of any soft tissue filler, may lead to serious complications, such as granuloma formation. This makes further research legitimate and necessary.