Dermal filler materials and botulin toxin

Human Histology and Persistence of Various Injectable Filler Substances for Soft Tissue Augmentation

An increasing number of soft tissue filler substances have been introduced to the beauty market outside the U.S. which lackexperimental and clinical data in support of their claim. Ten commercially available filler substances were examined for biocompatibility and durability: 0.1 cc of each substance was injected deep intradermally into the volar forearm of one of the authors and observed for clinical reaction and permanence. At 1, 3, 6, and 9 months the test sites were excised, histologically examined, and graded according to foreign body reactions classification. Collagen (Zyplast) was phagocytosed at 6 months and hyaluronic acid (Restylane) at 9 months. PMMA microspheres (Artecoll) had encapsulated with connective tissue, macrophages, and sporadic giant cells. Silicone oil (PMS 350) was clinically inconspicuous but dissipated into the tissue, causing a chronic foreign body reaction. Polylactic acid microspheres (New-Fill) induced a mild inflammatory response and had disappeared clinically at 4 months. Dextran microspheres (Reviderm intra) induced a pronounced foreign body reaction and had disappeared at 6 months. Polymethylacrylate particles (Dermalive) induced the lowest cellular reaction but had disappeared clinically at 6 months. Polyacrylamide (Aquamid) was well tolerated and remained palpable to a lessening degree over the entire testing period. Histologically, it dissipated more slowly and was kept in place through fine fibrous capsules. Polyvinylhydroxide microspheres suspended in acrylamide (Evolution) were well tolerated, slowly diminishing over 9 months. Calcium hydroxylapatite microspheres (Radiance FN) induced almost no foreign body reaction but were absorbed by the skin at 12 months.Host defense mechanisms react differently to the various filler materials, but all substances- resorbable or nonresorbable-appeared to be clinically and histologically safe, although all exhibit undesirable side effects. Since the mechanism of late inflammation or granuloma formation is still unknown, early histological findings are not useful in predicting possible late reactions to filler substances.

In Vitro Biocompatibility Evaluation of Nine Dermal Fillers on L929 Cell Line

Objective

Biomaterial research for soft tissue augmentation is an increasing topic in aesthetic medicine. Hyaluronic acid (HA) fillers are widely used for their low invasiveness and easy application to correct aesthetic defects or traumatic injuries. Some complications as acute or chronic inflammation can occur in patients following the injection. Biocompatibility assays are required for medical devices intended for human use, in order to prevent damages or injuries in the host. In this study, nine HA fillers were tested in order to evaluate their cytotoxicity and their effects on L929 cell line, according to the UNI EN ISO 10993 regulation.

Methods

Extracts were prepared from nine HA fillers, and MTS viability assay was performed after 24 h, 48 h, and 72 h of exposure of cells to extracts. Cells cultured with HA filler extracts were monitored for up to 72 h, counted, and stained with haematoxylin/eosin in order to evaluate the cell proliferation rate and morphology.

Results

None of the filler tested showed a cytotoxic effect. Two samples showed a higher vitality percentage and higher cell number while two samples showed a lower vitality percentage and lower cell number at 72 h.

Conclusion

Data obtained suggest that although examined fillers are not cytotoxic, they show different effects on the in vitro cell proliferation rate. In vitro studies of medical devices could lead to important implications since these could aid to predict effects about their in vivo application. These easy and rapid assays could be useful to test new materials intended for human use avoiding animal tests.

Inflammatory nodules following soft tissue filler use: a review of causative agents, pathology and treatment options

Nodule development is a common complication following the use of fillers for soft tissue augmentation and is commonly categorized as inflammatory or non-inflammatory in nature. Inflammatory nodules may appear anywhere from days to years after treatment, whereas non-inflammatory nodules are typically seen immediately following implantation and are usually secondary to improper placement of the filler. Although inflammatory nodules are more common with permanent fillers such as silicone, inflammatory nodule development following administration of temporary fillers such as hyaluronic acid and collagen has also been reported. Treated many times with corticosteroids due to their anti-inflammatory properties, inflammatory nodules may be secondary to infection or biofilm formation, warranting the use of alternative agents. Appropriate and prompt diagnosis is important in avoiding delay of treatment or long-term complications for the patient. This paper addresses the etiology, development, and studied treatment options available for inflammatory nodules secondary to each of the major classes of fillers. With this knowledge, practitioners may expeditiously recognize and manage this common side effect and thus maximize functional and aesthetic benefit.

Clinical comparison of two hyaluronic acid-derived fillers in the treatment of nasolabial folds: Mesoglow® and IAL System®

Hyaluronic acid (HA) dermal fillers are widely used to reduce the appearance of aging. However, comparative research on the efficacy and safety of products of similar composition is limited. We compared outcomes achieved with two non-cross-linked HA fillers of almost identical composition, Mesoglow® and IAL System® . Forty subjects with visible nasolabial folds (NLFs) were enrolled in a randomized study. Wrinkle severity was rated using the 5-point Wrinkle Severity Rating Scale (WSRS). Each subject was injected with Mesoglow® in one NLF and IAL System® in the other. An optimal cosmetic result was established at two weeks after a second treatment. Participants were then reassessed at 2, 6, and 12 weeks, respectively, post-optimal cosmetic result using the WSRS. The degree of improvement was also assessed by subjects and investigators using the Global Aesthetic Improvement Scale (GAIS). At baseline, the mean WSRS score was 3.20 ± 0.41. At the optimal cosmetic result, 98% of subjects showed a 1- or 2-point change in WSRS score with either treatment. All subsequent WSRS scores were significantly improved over baseline for both treatments. There was no significant difference between treatments or improvement in WSRS score at any point in time. Investigator GAIS scores at weeks 4 and 6 were slightly but not significantly higher for Mesoglow®-treated skin. There was no significant difference in the frequency of local adverse responses. No serious systemic adverse events occurred. This study indicates that Mesoglow® and IAL System® are equally effective in achieving short-term correction of NLFs, but the longevity of their effects is limited.

Short-term nanostructural effects of high radiofrequency treatment on the skin tissues of rabbits

The aim of this study is to quantitatively investigate the short-term effects of RF tissue-tightening treatment in in vivo rabbit dermal collagen fibrils. These effects were measured at different energy levels and at varying pass procedures on the nanostructural response level using histology and AFM analysis. Each rabbit was divided into one of seven experimental groups, which included the following: control group, and six RF group according to RF energy (20 W and 40 W) and three RF pass procedures. The progressive changes in the diameter and D-periodicity of rabbit dermal collagen fibrils were investigated in detail over a 7-day post-treatment period. The dermal tissues treated with the RF tissue-tightening device showed more prominent inflammatory responses with inflammatory cell ingrowth compared to the control. This effect showed more prominent with the passage of day after treatment. Although an increase in the diameter and D-periodicity of dermal collagen fibrils was identified immediately after the RF treatment, a decrease in the morphology of dermal collagen fibrils continued until post-operative day 7. Furthermore, RF treatment led to the loss of distinct borders. Increases in RF energy with the same pass procedure, as well as an increase in the number of RF passes, increased the occurrence of irreversible collagen fibril injury. A multiple-pass treatment at low energy rather than a single-pass treatment at high energy showed a large amount of collagen fibrils contraction at the nanostructural level.

Dermal Fillers: Do's and Dont's

Dermal fillers are an important tool in the armamentarium of an aesthetic dermatologist in the management of ageing skin. A surge in the use of fillers has been witnessed due to increasing awareness among people, easy availability of fillers and increased enthusiasm amongst the dermatologists and plastic surgeons to use this modality. In this era of evidence-based medicine and litigations against doctors, Dermatologists should be vigilant about different acts of omission and commission in the use of fillers. This article briefly discusses the dos and don'ts with respect to dermal fillers.

Dermal fillers: tips to achieve successful outcomes

Fillers have become a common aesthetic treatment for several cosmetic problems. Several types of fillers are available from different sources and of different longevities. It is important that the treating physician be aware of the different techniques of administration and their possible side effects. This article reviews the available literature on the subject.

Bio‐AlcamidTMin drug‐induced lipodystrophy

The development of new drugs to counter human immunodeficiency virus (HIV) infection has led to an increase in lipodystrophic syndrome among HIV-infected individuals receiving combination therapy. Bio-Alcamid(TM) is a recently developed polymeric substance that can be implanted to compensate for adipose effects. We have implanted this substance in 73 patients with up to three years' follow-up. The aesthetic results were deemed excellent by both physicians and patients. No implant dislocation, implant migration, granuloma, allergic reaction or intolerance were recorded.

[Fillers. An overview]

The demand for minimally invasive cosmetic procedures is increasing rapidly every year. In addition to botulinum toxin and laser treatments, the injection of dermal fillers is one of the most relevant methods. Dermal fillers can be used for a multitude of indications: wrinkles (fine to deep), lip augmentation, facial deformities, sunken scars, and HIV-related lipoatrophy in hands, neck and décolleté. There are currently 160 dermal fillers on the market. They differ greatly in terms of origin (own or cadaveric-derived, animal, bacterial fermentation or synthesis), duration of the effect and breakdown properties (temporary, semi-permanent, permanent), injection depth (dermal, subcutaneous, supraperiosteal), and risk profile. Physicians who administer dermal fillers should have a thorough knowledge of their characteristics and of the anatomy of the area to be treated. This is essential for correct administration and optimal aesthetic results. Prior to any treatment, details of the procedure, the desired effects, durability, and potential risks of the filler to be injected should be discussed with the patient. The choice of dermal filler, the injection technique, and the volume to be administered are determined according to the anatomic site, the type of defect, the desired effect, and physician experience.

[Treatment of wrinkles with botulinum toxin]

The use of botulinum toxin A for the treatment of wrinkles is increasing. Botulinum toxin A inhibits exocytosis of acetylcholine from 3 to 12 months, depending on the target tissue. Low-dose botulinum toxin A is used to smooth hyperkinetic facial lines. This is especially successful in the upper facial parts, since the target muscles (procerus, corrugator supracilii, frontalis, orbicularis oculi) all directly overlie the osseous structures of the face. This is not the case for the lower facial parts, and more side effects are encountered when treating, for example, wrinkles around the mouth. Contraindications to the use of botulinum toxin A are diseases affecting neuromuscular signal transduction, allergic reactions to components of the solution, therapy with aminoglycosides or acetylsalicylic acid prior to treatment, infections in the planned treatment area, and pregnancy and lactation. Alternative and complementary treatments include erbium-YAG or CO2 laser, as well as augmentation and surgical plastic procedures.

Combination therapy with BOTOXtm and fillers: the new rejuvnation paradigm

Until relatively recently, restoration of appearance by replacement of lost facial volume and muscular relaxation has been an illusory goal. With advances in the commercial availability of newer filling agents and a better understanding of the clinical esthetic effects of botulinum toxin A, remarkably sophisticated and refined results can now be achieved by using these noninvasive techniques. The combined use of BTX-A and filling agents, such as collagen and hyaluronic acid, can restore facial appearance by the dual mechanisms of reflation and relaxation. In addition, their combined use appears to increase the longevity of tissue dwell time of the filling agent. Current practices now strive to correct wrinkles by restoring volume and also relaxing the pull of muscles that create negative facial expressions such as glabellar folds, mouth frown, crow's feet, horizontal forehead lines, and perioral and cervical rhytides. As with any of the new technological innovations currently available, understanding of the differing properties of the agents used and education in optimal technique is essential to clinical and esthetic success.

In vitro andin vivo biocompatibility evaluation of a polyalkylimide hydrogel for soft tissue augmentation

Injectable fillers are commonly used in Plastic and Reconstructive Surgery to correct serious and slight aesthetic defects due to their low invasiveness and an easy implant technique procedure. Synthetic hydrogels are proposed as filler materials for their similarity with soft tissue and to avoid many disadvantages of naturally derived materials such as short persistence, allergenicity, and immunogenicity. Our studies are focused on the biocompatibility evaluation of a polyacrylic hydrogel containing alkylimide-amide groups and pyrogen free water (96%) (Bio-Alcamid by means of the in vitro cytotoxicity and mutagenicity assays and the in vivo skin irritation, sensitization test, and subcutaneous implant. All tests conducted on Bio-Alcamid showed no toxicity. It is a substance easy to inject and remove; it does not migrate, and its safety allows it to be a suitable filler for the correction of slight and also very serious aesthetic defects.

[Botulinum toxin and wrinkles: few side effects and effective combining procedures with other treatments]

Chemical denervation, through the biologic effect of botulinum toxin, provides a very effective, low risk, lasting treatment for hyperkinetic wrinkles, mainly of the upper face. Patients with such rhytides, when treated with surgical myotomies or other alternative medical treatments, are at greater risk and with potentially less lasting results. Botulinum toxin has been widely used for the last 20 years in many areas of medicine. It has been used for 13 years in dermatology and plastic surgery, without important complications or sequellae. Any complications appear to be reversible. In these two specialties, with the minute quantities (units) and volume of material injected, complications are infrequent; some of them are now anecdotal. The only main complication from a cosmetic point of view is blepharoptosis, which is more and more rare. Because of a better anatomical knowledge of the affected muscles, and our improved technique, risks are greatly reduced. In our two latest multicenter studies on glabellar wrinkles, between 2002 and 2004, we saw no blepharoptosis. Conversely, in case of dynamic wrinkles associated with muscle, fat, and skin relapse, and/or deep furrows, only surgical procedures and/or other surface treatments are effective. Botulinum toxin injections are not meant to replace upper, mid, or mandibular face and neck lifts; indeed, botulinum toxin injections may optimize results from these surgical procedures. These injections play a fundamental process in producing long lasting results. The current and future evolution, in cosmetic surgery, is toward full achieved, but focused, natural, and minimally invasive surgical procedures in combination with effective and minimal risk techniques such as the botulinum toxin injections. To optimize the effect of the medical procedures, botulinum toxin should be injected three weeks before surgery. In addition botulinum toxin injections may optimize and prolong the effect of the surface procedures, as lasers, peels and fillers. This medicosurgical combination is one of the examples that best describes the evolution of plastic and aesthetic surgery in 2004.

Non-ablative skin tightening with radiofrequency in Asian skin

BACKGROUND AND OBJECTIVES

The recent successful application of radiofrequency (RF) in non-ablative skin tightening for skin laxity has attracted attention worldwide. The efficacy and clinical effect of RF were assessed in Asian skin, with additional study on the duration of the effect and any complications.

STUDY DESIGN/MATERIALS AND METHODS

Eighty-five Japanese females were enrolled in the study for treatment of nasolabial folds, marionette lines, and sagging jowls with 6-month follow-up.

RESULTS

RF treatment was effective for nasolabial folds, marionette lines, and jowls. Objective physician evaluation found relatively good improvement at 3 months post-treatment, and even better improvement at the 6-month evaluation.

CONCLUSIONS

RF treatment was very satisfactory for skin tightening in Asian facial skin. When compared with published literature from the United States, the results suggested that there might be race-related differences in the treatment parameters.

[Aesthetic dermatology. Botulinumtoxin A and soft tissue augmentation]

Younger and younger patients are undergoing aesthetic procedures to achieve "wrinkle-free" aging. This has had great impact on the field of aesthetic dermatology. The rapid development of new indications and filler materials requires a critical approach to the available substances particularly concerning side effects and long-term effects. The quality of the chosen approach depends on the applied filler substance, clear indication the compliance of the patient and the experience of the physician. The growing expectations of patients require a critical analysis of the available therapy options. Botulinum toxin A is one of the preferred treatments for wrinkles secondary to facial expression. In addition there are a variety of biologically inert and completely resorbable filler materials such as collagen and hyaluronic acid and autologous materials such as fat implants or plasma gel available. This article gives an overview about the most common fillers and their use in aesthetic dermatology.

Type A botulinum toxin in the upper aspect of the face

The use of botulinum toxin type A (BTX-A) for facial rejuvenation was first systematically developed by Carruthers and Carruthers on the upper aspect of the face. In the early 1990s, the first studies of the cosmetic use of BTX-A were published. BTX-A was only approved in 2002, however, by the U.S. Food and Drug Administration when extensive cosmetic studies were evaluated. The treatment of facial wrinkles with BTX-A has truly changed the concepts held by physicians regarding facial rejuvenation, mainly on the upper aspect of the face. It is one of the most common cosmetic procedures currently performed by physicians.

[Skin, wrinkles and botulinum toxin]

OBJECTIVE

To present an up-to-date analysis about the use of botulinum toxin for treating facial lines and wrinkles.Method. - A systematic search of the literature was conducted to select the most recent or relevant publications on this topic, through Medline.

RESULTS

Out of the 583 articles retrieved, 90 were finally selected for the study.

DISCUSSION

Validity of using botulinum toxin for cosmetic use is demonstrated, together with contra-indications and different methods to objectivate the results. The different available types of toxin are presented and compared. Modalities of preparation, conservation, and waste disposal are detailed. Anatomical bases of muscular facial balance are reviewed, with techniques of injection presented for each site, and also with adjunctive procedures. Complications and side effects are described and analysed. Most complications can be prevented through: perfect knowledge of local anatomy;use of small volumes;orientation of the needle bevel towards the muscle body, injection within the muscle body if thick, more superficial if thin;application of ice on the skin pre- and post-injecting. Adding epinephrin or diluting with xylocaïne and epinephrin is not commonly used.

CONCLUSION

Botulinum toxin has found its way as a major component of the therapeutic armamentarium. Its efficacy for facial rejuvenation has made it extremely popular, but its use does follow strict rules, and should be restricted to soundly trained practitioners.