Silicone gel sheeting for healing hypertrophic scars: a WHAM evidence summary

The exact mechanisms of action responsible for the effectiveness of silicone gel dressings are unknown, although it has been proposed that static electricity generated by friction could be the reason for their anti-scarring effects. We compared the efficacy of a cushion of silicone filled with liquid silicone gel reported to induce greater negative static-electric charge with silicone gel sheeting in the treatment of hypertrophic and keloid scars. The size, volume, symptoms (tenderness and itching), and signs (color and induration) of hypertrophic (10 patients) or keloid scars (22 patients) were measured at baseline at 16 weeks following use of either the silicone gel cushion or silicone gel sheeting, as determined by random assignment. Both the silicone gel cushion and the silicone gel sheeting treatments were effective in decreasing scar volume, 53.0% and 36.3%, respectively. The percentages of keloids and hypertrophic scars benefiting from the silicone cushion and the silicone sheeting were similar with respect to reduction in tenderness (36.3% vs 33.3%), itching (45.5% vs 33.3%), and redness (0.1% vs 0.1%), and in the degree of softening (45.5 vs 25.0%). Both the silicone gel cushion and the silicone gel sheeting treatments were effective in the treatment of keloids and hypertrophic scars, although no statistically significant differences were found between the two treatment modalities.

Background: Widespread hypertrophic scars usually resulting from burn injuries or extensive soft tissue trauma is a common problem presented to plastic OPD. Non-invasive treatment like Pressure/compression therapy and siliconee sheets and gels are well-accepted, evidence-based recommendations for a long time. Very few studies are there for their combined effect on hypertrophic widespread scars. Aims and objectives of the study was to see the outcome of hypertrophic scar management following application of combined therapy of silicone gel and pressure garment.Methods: In the present study we have taken patients, who were randomly allotted in two groups. In one group only silicone gel was used for scar management while other group we applied silicone gel along with customized pressure garment locally for 6 months. Patients are seen in OPD monthly and after 6 months final results were analyzed, to see the effect of combined therapy.Results: Although silicone gel is alone is effective in widespread post burn scar, pressure garment provides a synergistic effects when used together. There is no significant change in colour and vascularity, but changes in scar thickness and pliability are most significant in combined therapy group.Conclusions: For small linear scar silicone gel treatment is alone sufficient, but for widespread hypertrophic scar this should always be used along with pressure garment therapy.

Keloid and hypertrophic scars are common and are caused by a proliferation of dermal tissue following skin injury. They cause functional and psychological problems for patients, and their management can be difficult. The use of silicon gel sheeting to prevent and treat hypertrophic scarring is still relatively new, and started in 1981 with treatment of burn scars. To determine the effectiveness of silicon gel sheeting for: (1) prevention of hypertrophic or keloid scarring in people with newly healed wounds (e.g. post surgery); (2) treatment of established scarring in people with existing keloid or hypertrophic scars. Trials were identified from searches of the Cochrane Wounds Group Specialised Register (searched September 2005), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 3, 2005); MEDLINE (1989 to June 2002); EMBASE (1988 to May 2002); CINAHL (1982 to May 2002) and reference lists of articles and relevant reviews. The major supplier of silicon gel sheeting (Smith and Nephew) was approached for details of unpublished, ongoing and recently published trials. Any randomised or quasi-randomised controlled trials, or controlled clinical trials comparing silicon gel sheeting for prevention or treatment of hypertrophic or keloid scars against no treatment, placebo, or any other treatment type except surgery. All relevant trials were assessed for methodological quality. Data were extracted independently by both reviewers using a standardized form, and the results cross-checked. All trials, meeting the selection criteria were assessed for methodological quality. Thirteen trials, involving 559 people, ranging in age from 2 to 81 years, were included in the review. The trials compared adhesive silicon gel sheeting with control; non-silicon gel sheeting; silicon gel plates with added Vitamin E; laser therapy; triamcinolone acetonide injection, and non-adhesive silicon gel sheeting. In the prevention studies, when compared with a no treatment option; whilst silicon gel sheeting reduced the incidence of hypertrophic scarring in people prone to scarring, (RR 0.46, 95% CI 0.21 to 0.98) these studies were highly susceptible to bias. Silicon gel sheeting produced a statistically significant improvement in scar elasticity, (RR 8.60, 95% CI 2.55 to 29.02), but again these studies were highly susceptible to bias. Trials evaluating silicon gel sheeting as a treatment for hypertrophic and keloid scarring are of poor quality and highly susceptible to bias. There is weak evidence of a benefit of silicon gel sheeting as a prevention for abnormal scarring in high risk individuals but the poor quality of research means a great deal of uncertainty prevails.

The Use of Silicone Gel in the Control of Hypertrophic Scarring

There is currently limited rigorous RCT evidence available about the clinical effectiveness of SGS in the treatment of hypertrophic scars. None of the included studies provided evidence on severity of scarring validated by participants, health-related quality of life, or cost effectiveness. Reporting was poor, to the extent that we are not confident that most trials are free from risk of bias. The limitations in current RCT evidence suggest that further trials are required to reduce uncertainty around decision-making in the use of SGS to treat hypertrophic 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.

So what is a keloid scar?

Background:A single-center study assessing the efficacy of Nagor’s Silgel STC-SE silicone gel to reduce the appearance of hypertrophic and keloid scars.Methods:A 16-week controlled study of 36 patients with hypertrophic or keloid scars. The subjects were divided between 2 cohorts: one assessing recently healed scars (<6 mo) and other assessing older scars (6 mo to 2 y). The efficacy of Silgel STC-SE on the scar was evaluated by skin hydration, skin moisture evaporation, skin elasticity, basic scar measurements, subjective patient questionnaire data, and image analysis. All subjects had data collected at baseline and weeks 1, 4, 8, 12, and 16. Photographs were taken for image analysis at baseline, week 8, and week 16. Statistical analysis was conducted on all data.Results:Twenty-nine patients completed the study (27 presented with hypertrophic scars and 2 with keloid scars), and 90% reported a marked improvement in their scar appearance. Patient questionnaire data showed great satisfaction with the product. Image analysis showed visual improvement with a statistically significant reduction of the “red” color of scars. Overall, scar dimensions were significantly reduced. There was a significant decrease from baseline levels in average scar length. Skin elasticity, skin hydration, and skin moisture evaporation did not change significantly from baseline.Conclusions:The results of this study indicate that Silgel STC-SE is an effective treatment in reducing the appearance and red color of hypertrophic scars up to 2 years old. Further study is required to draw significant conclusion in regard to the treatment of keloid scars.

Pressure-garment therapy for preventing hypertrophic scarring a er burn injury (Protocol)

Keloid and hypertrophic scars are common and are caused by a proliferation of dermal tissue following skin injury. They cause functional and psychological problems for patients, and their management can be difficult. The use of silicone gel sheeting to prevent and treat hypertrophic scarring is still relatively new and started in 1981 with treatment of burn scars. To determine the effectiveness of silicone gel sheeting for:(1) prevention of hypertrophic or keloid scarring in people with newly healed wounds (e.g. post surgery);(2) treatment of established scarring in people with existing keloid or hypertrophic scars. In May 2013 we searched the Cochrane Wounds Group Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE; and EBSCO CINAHL for this second update. Any randomised or quasi-randomised controlled trials, or controlled clinical trials, comparing silicone gel sheeting for prevention or treatment of hypertrophic or keloid scars with any other non surgical treatment, no treatment or placebo. We assessed all relevant trials for methodological quality. Three review authors extracted data independently using a standardised form and cross-checked the results. We assessed all trials meeting the selection criteria for methodological quality. We included 20 trials involving 873 people, ranging in age from 1.5 to 81 years. The trials compared adhesive silicone gel sheeting with no treatment; non silicone dressing; other silicone products; laser therapy; triamcinolone acetonide injection; topical onion extract and pressure therapy. In the prevention studies, when compared with a no treatment option, whilst silicone gel sheeting reduced the incidence of hypertrophic scarring in people prone to scarring (risk ratio (RR) 0.46, 95% confidence interval (CI) 0.21 to 0.98) these studies were highly susceptible to bias. In treatment studies, silicone gel sheeting produced a statistically significant reduction in scar thickness (mean difference (MD) -2.00, 95% CI -2.14 to -1.85) and colour amelioration (RR 3.49, 95% CI 1.97 to 6.15) but again these studies were highly susceptible to bias. There is weak evidence of a benefit of silicone gel sheeting as a prevention for abnormal scarring in high-risk individuals but the poor quality of research means a great deal of uncertainty prevails. Trials evaluating silicone gel sheeting as a treatment for hypertrophic and keloid scarring showed improvements in scar thickness and scar colour but are of poor quality and highly susceptible to bias.

Sir, I read with great interest the report by Puri et al. on the usage of silicone gel for the treatment of hypertrophic scars.[1] Puri et al. mentioned that “The results of the self-drying silicone gel have been satisfactory.[1]” Indeed, silicone gel is proved to be an effective choice. de Giorgi et al. reported that “silicone gel is able to reduce the formation of keloid and hypertrophic scars and the signs/symptoms associated with the healing process (paraesthesia, pulling sensation, alterations in colour.[2]” However, there are some points that need to be discussed. There is no control group in this work. Hence, it cannot imply any comparative effectiveness to other alternative treatments. Karagoz et al. recently performed a comparative study among silicone gel, silicone gel sheeting and topical onion extract, including heparin and allantoin, for the treatment of postburn hypertrophic scars and concluded that “Silicone products, either in gel or sheet, are superior to Contractubex in the treatment of the hypertrophic scar.[3]” Karagoz et al. also mentioned that “The therapist should select the most appropriate agent according to the patient’s need and guidelines of these signs.[3]” Further, comparative cost-effectiveness studies among various alternative choices should also be performed to obtain the data for decision-making for selection of the most appropriate method.

Comparative effect of topical silicone gel and topical tretinoin cream for the prevention of hypertrophic scar and keloid formation and the improvement of scars

To evaluate the individual effectiveness of needling therapy using the Dermapen (Dermapen, Salt Lake City, Utah) and topical therapy with silicone gel (Kelo-cote, Sinclair Pharma, London, England), and their combined effectiveness for the treatment of linear surgical scars, hypertrophic scars, and keloids. Twenty patients were randomly selected and equally divided into 2 groups (A and B), with each group of 10 including 6 patients with keloids and 4 with hypertrophic scars. Treatment assignments were random. In group A, the entire scar was treated by skin needling, with silicone gel applied to half of the scar. Patients in group B were treated with silicone gel on the whole scar, with only half of the scar also treated with skin needling. During follow-up visits, clinical photographs, evaluation of the scars' thickness, skin ultrasound, and modified Vancouver Scar Scale were performed. Group A showed an average improvement of 68% (P < .01) on the half of the scar with the combination treatment (skin needling plus silicone gel) compared with a 52% improvement on the half of the scar that was treated with only skin needling. Group B showed an average improvement of 63% (P < .01) where the combination treatment was performed, compared with 47% improvement on the area treated with only the silicone gel. In conclusion, the combination of these 2 treatments is safe and effective for the treatment of hypertrophic scars and keloids. These modalities achieved favorable results with each patient adhering to the study paramenters.

This study aimed to investigate the side effects of silicone gel sheet (Lady Care®) and evaluate its prophylactic efficacy in preventing abnormal scarring. Sixty women who underwent caesarean section were recruited from September 2016 to September 2017 in this prospective study. Lady Care® was applied from the 2nd to the 6th postoperative months. Side effects of Lady Care® were evaluated through medical examinations and questionnaires. A plastic surgeon diagnosed abnormal scarring. Pruritus was diagnosed in 25 (47.2%) patients; folliculitis, four (7.5%); dry skin, four (7.5%); contact dermatitis, three (5.7%); wound infection, two (3.8%); and epidermolysis, one (1.9%), albeit with mild severity. Following Lady Care® application, no abnormal scarring and mild hypertrophic scarring was observed in 32 (64.0%) and 18 (36.0%) patients respectively. Of seven patients with pre-existing hypertrophic scars, only two showed hypertrophic scarring after Lady Care® application. Our findings support the safety and prophylactic efficacy of Lady Care®. Impact Statement What is already known on this subject? The incidence of abnormal scarring, i.e. keloid or hypertrophic scar formation after caesarean section (CS) is reported to be ∼41%. Abnormal or excessive scar formation can lead to functional limitations, pruritus, pain and cosmetic issues. Studies have also shown a prophylactic effect of the application of silicone materials against the development of hypertrophic and keloid scars, though prohibitive cost and lack of adhesiveness of such gel sheets are known factors limiting their usage. What the results of this study add? The new silicone gel sheet ‘Lady Care®’ has strong adhesive properties and is consequently not easily peeled off. Furthermore, it is easy to use and economically efficient. What the implications are of these findings for clinical practice and/or further research? This is the first clinical trial on the application of Lady Care® silicone gel sheet for the prevention of CS scarring. Our findings support the safety and prophylactic efficacy of Lady Care®.

The effects of topically applied silicone gel and its silver derivative on the prevention of hypertrophic scarring in two rabbit ear-scarring models