Topical Silicone Research Articles

O5.4 Topical silicone gel versus placebo in promoting the maturation of burn scars; a randomized controlled trial

O5.4 Topical silicone gel versus placebo in promoting the maturation of burn scars; a randomized controlled trial

Topical Silicone Gel versus Placebo in Promoting the Maturation of Burn Scars: A Randomized Controlled Trial—The Pivotal Role of Statistics

Topical Silicone Gel versus Placebo in Promoting the Maturation of Burn Scars: A Randomized Controlled Trial—The Pivotal Role of Statistics

Reply: Topical Silicone Gel versus Placebo in Promoting the Maturation of Burn Scars: A Randomized Controlled Trial—The Pivotal Role of Statistics

Sir: We agree with Dr. Mangano that an accurate experimental design is essential for drawing valid conclusions from any clinical trial and that the required sample size should be calculated and fixed before starting a trial. We did perform an a priori sample size calculation but unfortunately this was not mentioned in the article. Based on data from previous studies, a difference in redness scores at follow-up of approximately the size of the score's standard deviation was anticipated. Comparing the follow-up measurements under the two conditions using a standard t test would then require 36 scars to be treated and evaluated (18 per treatment) to achieve 80 percent power when tested two-sided at a significance level 5 percent. To further increase power, an intraindividual comparison design was used in which subjects with two comparable scars were included. One of these scars was treated with silicone gel and the other was treated with the placebo cream. Based on the power analyses, the aim was to include 25 patients (50 scars) to correct for possible dropout. At the end of the inclusion period, 23 patients were included, which was considered to be sufficient. Martijn B. A. van der Wal, M.D. Burn Center Red Cross Hospital Beverwijk, The Netherlands Association of Dutch Burn Centers Beverwijk, The Netherlands Department of Plastic, Reconstructive, and Hand Surgery, VU University Medical Center Amsterdam, The Netherlands Paul P. van Zuijlen, M.D., Ph.D. Burn Center and Department of Plastic, Reconstructive, and Hand Surgery Red Cross Hospital Beverwijk, The Netherlands Association of Dutch Burn Centers Beverwijk, The Netherlands Department of Plastic, Reconstructive, and Hand Surgery, VU University Medical Center Amsterdam, The Netherlands Peter van de Ven, Ph.D. Department of Epidemiology and Biostatistics VU University Medical Center Amsterdam, The Netherlands Esther Middelkoop, Ph.D. Association of Dutch Burn Centers Beverwijk, The Netherlands Department of Plastic, Reconstructive, and Hand Surgery VU University Medical Center Amsterdam, The Netherlands

Positive response of a recurrent keloid scar to topical methyl aminolevulinate-photodynamic therapy

A 36-year-old Caucasian female of Iranian origin presented with a persistently raised dermal lesion under her chin, confirmed histologically to be a keloid scar. There was a 4-year history of a negative response to a range of conventional treatments including topical silicone gel sheets, steroid creams, steroid injections and surgical excision. In view of treatment failure and an in vitro study indicating a positive effect of photodynamic therapy (PDT)on keloid fibroblasts, we treated our patient's lesion with five sessions of methyl aminolevulinate photodynamic therapy (MAL-PDT) over a period of 5 months. Following this treatment regime, her keloid scar had considerably reduced in size and become flattened.The surface of the keloid also became smooth, with attenuation in erythema at the margin as well as an improvement in the colour of the scar, which was better matched to the surrounding skin. There was no recurrence at 1-year follow-up and this treatment resulted in an overall acceptable cosmetic outcome. This case report presents PDT as a potential treatment option for persistent keloid lesions unresponsive to conventional scar modulation therapies and suggests a need for further research in this area.

Phase 2 Cross-Over Multicenter Trial on the Efficacy and Safety of Topical Cyanoacrylates Compared with Topical Silicone Gel in the Prevention of Pathologic Scars

Many clinical studies on scar therapy are reported in the literature, but only silicone gel sheeting and corticosteroid injections are supported by accurate prospective controlled studies. This prospective multicenter cross-over phase 2 study tested the effectiveness of a topical cyanoacrylate compared with silicone gel in improving postsurgical scars Patients presenting with symmetric breast scars after augmentation or reduction mammaplasty were enrolled in the study. From the same day as stitch removal, the cyanoacrylate was applied on one side every 3 to 5 days and the silicone gel on the other side twice a day for 3 months. Assessments of patients and external observers using a visual analog scale were recorded at scheduled visits during 1 year, and scars were photographed. Objective evaluations included measurements of scar width, length, and elevation. The statistical significance of objective parameter modifications was analyzed using the Wilcoxon test Positive effects of both tested products were observed during the scar maturation process, and final scars of good quality were achieved without any major adverse effect. The topical cyanoacrylate proved to be more efficacious in preventing scar widening, and this result was statistically significant The tested topical cyanoacrylate had a positive effect on the scar maturation process at least comparable with that of topical silicone gel.

Enhanced Enlargement of Silicone Ocular Prostheses Achieved by Silicone Gel (MED-361)

Recently, silicone prostheses have been used instead of acrylic ocular prostheses. The authors sought to assess the ability of silicone gel to facilitate the growth of an ocular silicone prosthesis and to determine the best application modality to achieve maximal possible growth. Two ocular prostheses with similar baseline dimensions and contour were used for comparison of growth environment. One prosthesis was placed in an eyelid mold, while the other was placed in an open Petri dish. Silicone gel drops (MED-361; NuSil Technology, Carpinteria, CA, USA) were administered 3 times daily to both prostheses. Over the course of 41 days, an equal amount of enlargement occurred in all dimensions in both prostheses. Enlargement of a silicone prosthesis can be achieved by various modes of application of topical silicone gel.

Topical Silicone Gel versus Placebo in Promoting the Maturation of Burn Scars: A Randomized Controlled Trial

Silicone sheets are widely used in the treatment of hypertrophic scars, although application around joints may cause limited adherence and reduced movement. To approach these problems, a topical silicone gel was developed that can be applied easily in a thin layer, and that is nonrestrictive and less apparent. The objective of this study was to investigate the effectiveness of topical silicone gel in promoting the maturation of burn scars. Forty-six scars on 23 patients were included in a randomized, placebo-controlled, within-subject comparative, double-blinded, clinical trial and followed for 1 year. The mean age of the scars at inclusion was 4 months. Effectiveness on scar quality was evaluated using the Patient and Observer Scar Assessment Scale and the DermaSpectrometer. Significance was tested using repeated measures analyses and Wilcoxon paired-sample signed rank tests. Over all visits, the benefit on surface roughness was statistically significant (p = 0.012). At individual time points, the surface of the topical silicone gel-treated scars showed significantly less roughness (p = 0.014) at 3 months after start of the treatment, and the topical silicone gel-treated scars were significantly less itchy (p = 0.018 and p = 0.013, respectively) at 3 and 6 months. Topical silicone gel significantly improves the surface roughness of burn scars, and patients experience significantly less itching in the first half year after application.

Silicone-Based Scar Therapy: A Review of the Literature

Hypertrophic and keloid scars still are among the banes of plastic surgery. In the treatment arsenal at the disposal of the plastic surgeon, topical silicone therapy usually is considered the first line of treatment or as an adjuvant to other treatment methods. Yet, knowledge concerning its mechanisms of action, clinical efficacy, and possible adverse effects is rather obscure and sometimes conflicting. This review briefly summarizes the existing literature regarding the silicone elastomer's mechanism of action on scars, the clinical trials regarding its efficacy, a description of some controversial points and contradicting evidence, and possible adverse effects of this treatment method. Topical silicone therapy probably will continue to be the preferred first-line treatment for hypertrophic scars due to its availability, price, ease of application, lack of serious adverse effects, and relative efficacy. Hopefully, future randomized clinical trials will help to clarify its exact clinical efficacy and appropriate treatment protocols to optimize treatment results.

The Efficacy of Topical Silicone Gel Elastomers in the Treatment of Hypertrophic Scars, Keloid Scars, and Post–Laser Exfoliation Erythema

The Efficacy of Topical Silicone Gel Elastomers in the Treatment of Hypertrophic Scars, Keloid Scars, and Post–Laser Exfoliation Erythema

The efficacy of silicone gel for the treatment of hypertrophic scars and keloids.

Topical self drying silicone gel is a relatively recent treatment modality promoted as an alternative to topical silicone gel sheeting. Thirty patients with scars of different types including superficial scars, hypertrophic scars, and keloids were treated with silicon gel application. The results of the self-drying silicone gel have been satisfactory.

LBF®‘no-sting’ barrier wipes: skin care using advanced silicone technology

The past decade has seen a huge growth in the application of silicone-based products to the healthcare market, with this technology finding its way into diverse areas ranging from the manufacture of disposable contact lenses to urinary catheters, and the development of a new generation of wound and skin care products. However, the current development of topical silicone treatments to protect the skin is not a new idea, but rather a renaissance, with the first of these products being developed in the 1940s as a substance known as 'water glass' or sodium silicate. Although the years have past, the challenges for nursing remain the same, with the need to protect vulnerable areas of the skin and the prevention of skin breakdown forming one of the cornerstones of professional care across all spheres of practice. This article considers the role that silicone-based barrier films, such as CliniMed's LBF, can play in the prevention and management of skin breakdown.

The Efficacy of Topical Silicone Gel Elastomers in the Treatment of Hypertrophic Scars, Keloid Scars, and Post–Laser Exfoliation Erythema

Dermatix is a Food and Drug Administration (FDA)-registered substantial equivalent to silicone gel sheeting for the prevention and management of hypertrophic scars and keloids. A 90-day prospective study evaluated the efficacy of Dermatix, silicone gel sheeting, and a combination of these treatments in improving scars for 30 patients. Each patient had a bilateral scar that served as an untreated control. The outcome measures included profilometry analysis of scar topography before and after punch biopsies of the control and treated scars, symptoms associated with the scars, and patient evaluations of the ease of treatment. The results showed better resolution and improvement of scars with Dermatix treatment or the combined use of Dermatix and silicone gel sheeting than with silicone gel sheeting alone. Wound erythema was reduced, and collagen architectural reorientation was demonstrated histologically. Patients rated Dermatix as easier to use than silicone gel sheeting. Both Dermatix and silicone gel sheeting reduced symptoms of itching, irritation, and skin maceration. The results of this study indicate that Dermatix is a useful treatment for the management of abnormal scarring.

Clinical Evaluation of a New Self-Drying Silicone Gel in the Treatment of Scars: A Preliminary Report

Topical silicone gel sheeting and intralesional steroids are the only evidence-based recommendable forms of treatment to control the quality of a scar. The advantages and disadvantages of both are well known. This study was undertaken to verify the efficacy of a new topical silicone treatment: a self-drying spreadable gel that needs no means of fixation and cannot be seen because of complete transparency. Fresh surgical scars treated with the tested product showed significantly better outcomes than those untreated in a prospective trial involving a group of 160 patients. Patient compliance was particularly good, especially for scars on exposed areas such as the face, where the traditional gel sheeting is frequently discontinued at an early stage by patients who object to its visibility. The results of the self-drying silicone gel have indeed been satisfactory. Considering the effective results obtained and the good patient compliance, the authors currently rate this concept of treatment as the first choice for preventing hypertrophy of recent scars.

The Efficacy of Magnetic Disks for the Treatment of Earlobe Hypertrophic Scar

Ear piercing has been widely performed for various reasons, but it may cause hypertrophic scarring and its attendant cosmetic problems and/or subjective symptoms, such as pruritus or pain. Many treatment methods have been applied alone or in combination, including surgical excision, steroid injection, compression, radiation, topical silicone application, and so on. Although each modality or combined therapy has its advantages and disadvantages, in the authors' opinion, compressive therapy combined with surgical excision is the most effective method in many respects. However, the peculiar shape of the earlobe does not allow for easy compression. Thus, many compressive devices have been developed that are not wholly satisfactory in terms of effectiveness, appearance, size, or convenience. The authors describe a newly developed method for the treatment of hypertrophic scarring of the earlobe that uses magnetic disks. They treated 47 patients (91 auricles) with a hypertrophic scar on the earlobe that underwent compressive therapy using magnetic disks after surgical excision from April to December 2002. The use of magnetic disks proved effective, and they believe that it offers many advantages as a compressive device.

The Effect of Silicone Gel on Basic Fibroblast Growth Factor Levels in Fibroblast Cell Culture

Topical silicone gel has shown promise in the treatment of hypertrophic and keloid scars. However, its mechanism of action remains undetermined. To investigate whether the presence of silicone alters the secretion of basic fibroblast growth factor (bFGF), a key cytokine involved in the scar formation process. Serum-free fibroblast cell cultures were established from normal, keloid, and fetal skin, which heals without scarring, and exposed to silicone gel. Serial cell counts were performed, and supernatants were collected for bFGF quantification by enzyme-linked immunosorbent assay at 4, 24, 72, and 120 hours. Growth curves were similar and no statistically significant differences in population doubling times were observed between treated and untreated specimens. Statistically significant differences in bFGF levels between treated and untreated normal fibroblasts were observed at 24, 72, and 120 hours after cell culture initiation. Differences in bFGF levels between treated and untreated fetal fibroblasts that approached statistical significance were observed at 72 and 120 hours. These results suggest that silicone gel is responsible for increased bFGF levels in normal and fetal dermal fibroblasts. We postulate that silicone gel treats and prevents hypertrophic scar tissue, which contains histologically normal fibroblasts, by modulating expression of growth factors such as bFGF. Our data support the hypothesis that substances that favorably influence wound healing do so by correcting a deficiency or overabundance of the growth factors that orchestrate the tissue repair process.

Hypertrophic scars and keloids: etiology and management.

Keloid and hypertrophic scars have affected patients and frustrated physicians for centuries. Keloid and hypertrophic scars result from excessive collagen deposition, the cause of which remains elusive. Clinically, these scars can be disfiguring functionally, aesthetically, or both. A thorough understanding of the pathophysiology and clinical nature of the scar can help define the most appropriate treatment strategy. Although many articles have been published on the management of hypertrophic and keloid scars, there is no universally accepted treatment protocol. Prevention of keloid and hypertrophic scars remains the best strategy; therefore, those patients with a predisposition to develop excessive scar formation should avoid nonessential surgery. Once a scar is present, there are many treatments from which to choose. Hypertrophic scars and keloids have been shown to respond to radiation, pressure therapy, cryotherapy, intralesional injections of corticosteroid, interferon and fluorouracil, topical silicone or other dressings, and pulsed-dye laser treatment. Simple surgical excision is usually followed by recurrence unless adjunct therapies are employed. Biologic agents that are directed towards the aberrant collagen proliferation that characterizes keloid and hypertrophic scars might be an important addition to the current armamentarium of modalities in the near future.

The effect of silicone gel sheets on perfusion of hypertrophic burn scars.

The mechanism of action of topical silicone gel sheets on hypertrophic scars is not well understood and their effect on the blood flow within hypertrophic scars has not been investigated. The purpose of this study was to examine whether application of silicone gel sheets produced any acute effects on blood flow in hypertrophic burn scars. Perfusion of hypertrophic scars and adjacent normal skin was measured using a laser Doppler with and without application of silicone gel sheets. Continuous measurements were made for 5 minutes before gel application, for 30 minutes during gel application and for 5 minutes following gel removal. Surface temperature of the scar was continuously monitored. An occupational therapist, blinded to the perfusion level, rated each scar using the Vancouver Scar Scale. Eighteen scars and adjacent control sites in sixteen adult burn patients (11 male, 5 female; mean age: 42 +/- 14 years) were evaluated. The mean scar age was 5.4 +/- 3.7 months. The mean Vancouver Scar Scale was 5.5 +/- 2.4. Hypertrophic scars demonstrated higher perfusion measurements at baseline compared to control areas (58.5 +/- 19.3 flux units vs 25.0 +/- 8.4 flux units; P < 0.001). Application of silicone sheeting gel did not significantly alter perfusion in either the hypertrophic scar or normal tissue from the baseline measurements. However, application of silicone gel sheeting did significantly increase the mean baseline surface temperature of the hypertrophic scar from 29 +/- 0.8 degrees C to 30.7 +/- 0.6 degrees C (P < 0.001). The mechanism of action of silicone gel sheeting probably does not involve an acute alteration in blood flow within the scar. However, surface temperature of the scar increased significantly following gel application, raising the possibility that temperature alteration is involved in the mechanism of action.

Prevention and Treatment of Keloids with Intralesional Verapamil

Background: The current treatment of keloids is based on surgery, medical therapy and physical treatment. The optimal treatment remains undefined. Objective: This clinical study determines the effectiveness of verapamil hydrochloride on the prevention and treatment of keloids. Methods: Two groups of patients with keloids were divided according to lesion site and age. The first group was treated by perilesional surgical excision of keloids and topical silicone, combined with adjuvant treatment of intralesional 2.5 mg/ml verapamil hydrochloride injections administered at timed intervals. The second group served as control, receiving the same treatment except the verapamil hydrochloride. Results: A periodical examination to check specific clinical parameters and an 18-month follow-up determined that keloids were cured in 54% of the cases in the first group, compared to 18% in the second group. Moreover, in the remaining 36% of patients in the first group in whom keloids recurred, there was an improvement in size and above all in consistence. Conclusion: These findings suggest that verapamil hydrochloride is an effective tool for the prevention and therapy of keloids.

Prevention of Hypertrophic Scars and Keloids by the Prophylactic Use of Topical Silicone Gel Sheets Following a Surgical Procedure in an Office Setting

Prevention of Hypertrophic Scars and Keloids by the Prophylactic Use of Topical Silicone Gel Sheets Following a Surgical Procedure in an Office Setting

Effects of silicone gel sheet on the stratum corneum hydration

Various groups have reported the efficacy of treatment with topical silicone gel sheet (SGS) for keloids and hypertrophic scars. Because its hydrating effect on the stratum corneum (SC) has been suggested as a mechanism underlying its therapeutic effectiveness, we evaluated it by comparing it with simple plastic film occlusion. With biophysical instruments we assessed the water content of the skin surface as well as its water evaporation on the flexor aspects of bilateral forearms of 10 healthy volunteers for 30min after removal of dressings of SGS or a plastic film that were applied either for 1 day or for 7 days. Occlusion with SGS or plastic film induced hydration of the skin surface, which was followed by an initial quick and later slow process of dehydration when the skin was exposed to the ambient atmosphere. The magnitude of the increase in hydration induced by SGS was always smaller than that of the plastic film occlusion and, unlike the latter treatment, hydration became less with repetition of SGS treatment. On day 7, the SC hydration quickly reduced to the level of non-treated control skin after removal of the dressings. An in vivo test demonstrated that the water-holding capacity of the SC normalised after 7 days of SGS treatment. SGS probably produces a favourable condition for the skin by protecting it from various environmental stimuli, while keeping the SC in an adequately but not over-hydrated condition.