ArteFill: A Third-Generation Permanent Dermal Filler and Tissue Stimulator

The technical and physiologic shortcomings associated with prior generations of polymethylmethacrylate (PMMA) dermal fillers have been reduced significantly since their original market introduction in 1989. For example, the PMMA microspheres in the third-generation product ArteFill meet the new limit set by the FDA of less than 1 particle below 20 micrometers per 100 microspheres (< 1% by the number). Therefore, it is expected that the already low granuloma rate following injections with second-generation product Artecoll (1:5000) will be reduced further with injections of ArteFill. In the authors' experience, both Artecoll and ArteFill have proven to be safe, predictable, and effective dermal fillers. It is anticipated that Artefill will receive FDA approval in late 2006 and will be marketed internationally.

Treatment options for dermal filler complications

The author contends that early adverse reactions to dermal fillers are caused by a superficial injection technique and that late adverse reactions result from unique patient responses. He has found all complications treatable with a correct dose of intralesional steroids or inconspicuous surgical entry. Here he provides guidelines for injection techniques and treatment for complications.

Migration studies and histology of injectable microspheres of different sizes in mice

Injectable dermal filler materials consist of either fluids, biological fragments, or suspensions of particles or microspheres. Particles and microspheres are said to "migrate," but migration can occur only when they are injected into blood vessels. To evaluate biocompatibility and transport, five nonresorbable polymethylmethacrylate microspheres of various sizes, suspended in different carriers, as well as resorbable polylactic acid and dextran microspheres were injected subcutaneously into mice. The five implantation sites were the right cheek, right axilla, right groin, urethra, and the right quadriceps muscle of the thigh. These sites were excised along with the local lymph nodes, lungs, liver, and spleen at 1, 3, 6, and 9 months after injection. Polymethylmethacrylate microspheres of 4 microm and 8 microm were phagocytosed but not transported to lymph nodes or distant organs. Larger microspheres of 20, 40, and 100 microm were encapsulated by connective tissue, macrophages, and giant cells. Polylactic acid microspheres caused a mild inflammatory response and had disappeared at 6 months. Dextran microspheres caused a pronounced foreign-body reaction and were phagocytosed at 9 months. The extremely large carbon-coated spheres of 200 to 500 microm in diameter "migrated" up to 1 cm from the implantation site. With the exception of an erroneous intravenous injection, no migration or transportation of any of the injected microspheres to lymph nodes or filter organs was seen. Obviously, the collagen glue released no microspheres. After subdermal injection, the collagen carrier substance kept the microspheres apart as a scaffold for tissue ingrowth, whereas all other carrier substances, such as gelatin, hyaluronic acid, or alginate, separated soon after injection, thereby causing agglomeration of the microspheres.

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 lack experimental 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.

Soft tissue augmentation with artecoll: 10-year history, indications, techniques, and complications

Most of the biologic filler materials that increase the thickness of the corium in a wrinkle line are phagocytosed within a certain time. Therefore, a lasting effect can only be achieved with nonresorbable synthetic substances. Artefill consists of 20 volume percent microspheres of polymethyl-methacrylate and 80 volume percent of bovine collagen. Beneath the crease, the microspheres with their exceptional surface smoothness stimulate fibroblasts to encapsulate each individual one of the 6-million microspheres contained in 1 mL of Artefill. Collagen is merely a carrier substance that prevents the microspheres from agglomerating during tissue ingrowth. The 20 volume percent of microspheres in Artefill provides the scaffold for the 80% volume of connective tissue deposition, a complete replacement of the injected collagen. The filler material beneath a crease acts like a splint and prevents the possibility of its further folding, thereby allowing the diminished thickness of the corium in a crease to recover. This recovery process is well known even in older patients with facial paralysis or after a stroke, whose facial wrinkles and furrows on the paralyzed side disappear over time.

Nail regeneration by elongation of the partially destroyed nail bed

Patients with partially destroyed fingernails tend to hide them, and such patients often do not find help because fingernails are considered of little functional value. To improve the aesthetic appearance of such nails, a simple excision of the destroyed nail matrix can stimulate the growth of the residual healthy matrix and regenerate the nail. Prerequisite is a healthy nail residue of at least the lunula. An excision of an en bloc, crescent-shaped, full-thickness scar, 5 mm at its greatest width and extending from one lateral nail fold to the other, increases the length of the nail plate. Together with the matrix, the nail will grow about 4 mm distally. A second crescent-shaped excision 1 to 2 months later will further lengthen the nail until it has gained full length. Normal nail growth was achieved in 11 patients who had partially scarred nail beds after mycosis or trauma.

Phagocytosis of different particulate dermal filler substances by human macrophages and skin cells

BACKGROUND

Foreign substances have been introduced into the human body with varying degrees of success. Polymethylmethacrylate (PMMA) microspheres of different sizes recently have been manufactured for use as a filler substances in the skin and other organs.

OBJECTIVE

To establish whether the size of PMMA microspheres determines whether various cell types initiate phagocytosis.

METHODS

The capacity of three different cell lines-U-937 cells, XS 106 and XS 52 Langerhans cells, and HaCaT keratinocytes-to phagocytose microspheres of varying sizes was examined using light and confocal microscopy as well as fluorescence-activated cell sorter (FACS) analysis. Tumor necrosis factor (TNF)-alpha secretion was also determined.

RESULTS

The U-937 cells, keratinocytes, and Langerhans cells could phagocytose PMMA particles of 20 microm or smaller. Microspheres larger than 20 microm were not ingested by any of the cells.

CONCLUSION

Microspheres larger than 20 microm have a lower likelihood of being phagocytosed. Thus this study suggests that microspheres 40-50 microm in diameter are less likely to initiate an inflammatory reaction when injected into the dermis and subdermis as a filler substance. On the other hand, microparticles made of silicone and polymethacrylate were phagocytosed, possibly because of their different structure.

International Task Force on Volunteer Cleft Missions

The International Task Force on Volunteer Cleft Missions was set up to provide a report to be presented at the Eighth International Congress of Cleft Palate and Associated Craniofacial Anomalies on September 12, 1997, in Singapore. The aim of the report was to provide data from a wide range of different international teams performing volunteer cleft missions and, thereafter, based on the collected data, to identify common goals and aims of such missions. Thirteen different groups actively participating in volunteer cleft missions worldwide were selected from the International Confederation of Plastic and Reconstructive Surgery's list of teams actively participating in volunteer cleft missions. Because of the time frame within which the committee had to work, three groups that did not respond by the stipulated deadline were omitted from the committee. The represented members and their respective institutions have undertaken more than 50 volunteer cleft missions to underdeveloped nations worldwide within the last 3 years. They have visited over 20 different countries, treating more than 3,500 patients worldwide. Based on the data collected and by consensus, the committee outlined recommendations for future volunteer cleft missions based on 1) mission objectives, 2) organization, 3) personal health and liability, 4) funding, 5) trainees in volunteer cleft missions, and 6) public relations. The task force believed that all volunteer cleft missions should have well-defined objectives, preferably with long-term plans. The task force also decided that it was impossible to achieve a successful mission without good organization and close coordination. All efforts should be made, and care taken, to ensure that there is minimal morbidity and no mortality. Finally, as ambassadors of goodwill and humanitarian aid, the participants must make every effort to understand and respect local customs and protocol. The main aims are to provide top-quality surgical service, train local doctors and staff, develop and nurture fledgling cleft programs, and, finally, make new friends.

A classification of facial wrinkles

An increasing number of injectable filler materials for facial wrinkles and folds points to the need for objective measurements of their effectiveness. Patient satisfaction is the goal, but proof of the value of a particular product requires objective measurement. A wrinkle assessment scale was developed as a simple tool for use by plastic surgeons, dermatologists, and aesthetic surgeons who want to assess the changes resulting from injecting filler materials in their patients. By correlating the grade of the wrinkle in the reference photographs with the wrinkle in a patient's face, a classification of 0 to 5 is assigned. Reliability of the scale was assessed by "live" judgment of 76 wrinkles by nine observers. The same rating was given to 92.7 percent of all wrinkles. In a second trial, photographs from 130 wrinkles were presented to eight observers who rated 89.4 percent of all wrinkles equally. A significant correlation of 87 percent was found between subjective ratings and objective wrinkle depth measured by profilometry on 40 silicone impressions. Manufacturers, monitors of clinical trials, health authorities, and most important, patients will benefit from objective data on current and new injectable materials.

[Reconstruction of severe facial defects due to noma]

Noma is an ulcerative-necrotizing gingivo-stomatitis eventually leading to severe destruction of the midface, including lips and cheek, maxilla/mandible, nose and rarely the orbit. The defects are usually unilateral. Children from economically underdeveloped countries are predominantly affected. Medically untreated the disease has a high mortality rate, which can be dramatically lowered by adequate antibiotic therapy started in time. Predisposing factors include malnourishment, immunosuppression, and poor oral hygiene. Forty-eight noma patients were surgically treated in Sokoto, Nigeria during October 1997 by an Interplast Germany team sponsored by AWD Stiftung Kinderhilfe. Interdisciplinary surgical strategies and results, e.g. ankylosis release, local flap coverage and 12 pedicled musculocutaneous latissimus dorsi island flaps, as well as a noma classification (NOMAC), are presented.

The resection of gastrocnemius muscles in aesthetically disturbing calf hypertrophy

In some patients, oversized calves lead to mental distress and avoidance of certain social activities. They hide their legs in pants and seek medical advice. If the thickness of the subcutaneous fat is normal and cannot be diminished by liposuction, the oversized calves are caused by pure muscle hypertrophy. Using the gastrocnemius for muscle flaps in covering knee defects does not impair the function of the patient's leg; therefore, resection of the total gastrocnemius muscle for aesthetic calf reduction was performed in 15 consecutive patients without any lasting impairment with stability or sports activities. The patient was placed in a prone position, and the muscles were bluntly freed and pulled through two incisions of 5-cm length in the hollow of the knee and above the Achilles tendon. The resected muscles weighed between 410 and 810 g each. In two patients, the sural nerve was stretched or cut during the operation. The consequent numbness of the lateral ankle and sole persisted for 9 and 13 months, respectively. All 15 patients were satisfied with the results; none complained of lack of stability or insecurity in walking; and all became active in sports or changed their dress habits.

PMMA-Microspheres (Artecoll) for long-lasting correction of wrinkles: refinements and statistical results

The corium is diminished to about half of its thickness in skin defects and wrinkles. All biological materials that increase the thickness of the corium are resorbed within a certain time. Therefore, a lasting effect can be achieved only with nonresorbable synthetic substances. Artecoll consists of microspheres of 30-40 microm in diameter, of exceptional surface smoothness, purity, and homogeneity related to PMMA. These microspheres are suspended in atelocollagen which serves as a vehicle for subdermal implantation. Due to its smooth surface and consequential lack of electrical charges, each single microsphere is immediately encapsulated with the patient's own collagen fibers, thus preventing dislocation. Within 3 months, collagen (making up 75% of Artecoll) is replaced by the body's own connective tissue. The microspheres (25% of Artecoll) serve merely as a stimulus to the fibroblasts. Indications for Artecoll are all facial folds, lip- and philtrum augmentation, chin- and malar augmentation, dark-shadowed eyelids, enophthalmos, bony defects in face and hands, nipple reconstruction and augmentation, and urinary incontinence. Questionnaires were sent to all patients who had received Artecoll in 1993 and 1994. Of a total of 950 questionnaires sent, 515 were returned by September 1995. Satisfaction was rated "very good" in 29%, "good" in 38%, "satisfactory" in 23%, and "no difference" in 8% of the patients. The question, "Would you repeat the treatment again?" was answered by 91% of the patients with "yes." The overall complication rate was 3%. Strictly subdermal implantation will prevent longer lasting redness or visibility of the Artecoll.

Elevated levels of testosterone receptors in keloid tissue: an experimental investigation

Testosterone-binding receptor protein analyses were performed in keloids of 24 patients. According to their clinical appearance (hyperemia, pain, rapid growth, etc.), the lesions were subdivided into regions of minor and major clinical keloid activity. Biopsies were taken from active and inactive parts of the keloids, respectively, as well as from normal adjacent skin. The mean receptor amount in femtomoles per milligrams of tissue was 0.046 for active (SD = 0.037), 0.038 for inactive keloidal lesions (SD = 0.032), and 0.012 for normal skin. The corresponding receptor amount per microgram of DNA was 3.356 fmol (SD = 2.171) for active, 2.077 fmol (SD = 1.427) for inactive keloidal, and 1.010 fmol (SD = 1.190) for normal tissue. Statistical evaluation was performed using a two-way analysis of variance, with the two factors being individual subject and type of tissue. When differences were found, then Tukey's comparison was done to assess where those differences were. Comparisons of the receptor amount per milligram of tissue significant at the 0.05 level revealed significant differences between active keloid tissue and normal skin tissue and inactive and normal tissue (p < 0.01) respectively, while different receptor amount per microgram of DNA was significant between active and inactive and active and normal tissue (p < 0.01). These data suggest that elevated androgen receptor levels exist in clinical active keloid tissue and that possible therapeutic means might include topical antiandrogen therapy.

The tuberous breast deformity: classification and treatment

To date there are many descriptive terms for the tuberous breast deformity but there is no widely accepted nomenclature. A retrospective study was undertaken of 68 tuberous breasts and the operative corrections performed. The deformities were classified into four types. Type I (hypoplasia of the lower medial quadrant), type II (hypoplasia of the lower medial and lateral quadrants, sufficient skin in the subareolar region), type III (hypoplasia of the lower medial and lateral quadrants, deficiency of skin in the subareolar region) and type IV (severe breast constriction, minimal breast base). Areolar prolapse, usually regarded as a major symptom, was only found in 30 (44%) deformed breasts. Postoperative review of 51 breasts in 31 patients showed that type I cases treated by reduction mammaplasty of adequately sized breasts or augmentation of hypoplastic breasts had excellent results. These procedures with additional spreading of the breast tissue in type II deformities give good results. Severe cases (types III and IV) treated by augmentation and tissue spreading procedures have an unsatisfactory shape and have a 'second crease' deformity. For types III and IV, additional skin in the subareolar region by tissue expansion or flap procedures is necessary. There is no one method to correct 'the' tuberous breast but there are many procedures which should be used according to the type of deformity. The classification developed could end the confusion in nomenclature.

[Treatment of wrinkles by Artecoll implant and resurfacing with the CO2 laser]

In general, all biological materials are resorbed in places where they do not belong. Therefore, artificial substances have to be implanted under deep skin folds and skin defects in order to achieve a permanent skin augmentation. Artecoll, a suspension of polymethylmetcrylate (PMMA)-microspheres in collagen solution, has been proven, for more than 5 years, to underlay wrinkles effectively without noticeable side-effects. Small wrinkles around the eyes, the mouth and cheeks, however, have to be treated by dermabrasion, chemical peel or vaporization by CO2-laser. Using all three methods, the effectiveness depends on the depth of skin traumatisation. Resurfacing using the CO2-laser has the advantage of absolute precision, no bleeding, less swelling and faster healing-but still high costs.

PMMA microspheres (Artecoll) for skin and soft-tissue augmentation. Part II: Clinical investigations

Artecoll is an injectable implant for long-lasting correction of wrinkles and other skin defects. Artecoll consists of fine polymethyl-methacrylate (PMMA) microspheres suspended 1:3 in a 3.5% collagen solution. The microspheres are characterized by exceptional surface smoothness, homogenicity, and purity. The size of the microspheres of 30-40 microns diameter is small enough to allow subdermal implantation using a 27-gauge needle. Phagocytosis and dislocation of the implant is prevented by fast encapsulation of each single microsphere with connective tissue. Increased scarring but no granuloma formation has been detected as is common with other injectable implants with irregular surfaces. The experience from more than 600 patients and a prospective study in 118 patients with 200 implantation sites were evaluated. The good early results have continued for 5 years. Of the patients evaluated, 89.5 percent were satisfied and would ask for the treatment again. The overall complication rate is very low, and prolonged redness or visible granules are due to implantations that are too superficial. Other applications in soft-tissue augmentation are discussed.

Free transplantation of fat autografts expanded by tissue expanders in rats

Inguinal fat pads of 28 rats were expanded by tissue expanders for 10 days and transplanted to the back of the same animal. The non-expanded contralateral inguinal fat pads were also transplanted and served as controls. Histology showed that adipocytes lose their lipid droplets under mechanical pressure; the expanded adipocytes have an elongated contour with a central nucleus. By the end of the expansion period, the thickness of the fat pads had decreased by 53%. One week after transplantation, expanded fat grafts had regained their previous volume with little sign of necrosis. Among normal adipocytes numerous smaller cells, containing multiple vacuoles, were seen. In contrast, about 25% of the substance of the non-expanded control fat graft consisted of necrotic oil cysts. These findings indicate that pre-expanded fat grafts survive better.