Occlusion and hydration of scars: moisturizers versus silicone gels.

BACKGROUND: The mainstay of non-invasive scar management, consists of pressure therapy with customized pressure garments often combined with inlays, hydration by means of silicones and/or moisturizers as well as UV protection. It is generally accepted that scar dehydration resulting from impaired barrier function of the stratum corneum and expressed by raised trans epidermal water loss (TEWL) values, can lead to increased fibroblast activity and thereby hypertrophic scar formation. However, we have reached no consensus on exactly what optimal scar hydration is nor on barrier function repair: by means of silicone sheets, liquid silicone gels or moisturizers. Occlusive silicone sheets almost completely prevent TEWL and have been shown to be effective. Nevertheless, many important disadvantages due to excessive occlusion such as difficulties in applying the sheets exceeding 10-12 h, pruritus, irritation, and maceration of the skin are limiting factors for its use. To avoid these complications and to facilitate the application, liquid silicone gels were developed. Despite a reduced occlusion, various studies have shown that the effects are comparable to these of the silicone sheets. However, major limiting factors for general use are the long drying time, the shiny aspect after application, and the high cost especially when used for larger scars. Based on excellent clinical results after using three specific moisturizers for scar treatment in our patients, we wanted to investigate whether these moisturizers induce comparable occlusion and hydration compared to both each other and the widely recognized liquid silicone gels. We wanted to provide a more scientific basis for the kind of moisturizers that can be used as a full-fledged and cost-effective alternative to silicone gel. METHODS: A total of 36 healthy volunteers participated in this study. Increased TEWL was created by inducing superficial abrasions by rigorous (20x) skin stripping with Corneofix® adhesive tape in squares of 4 cm². Three moisturizers and a fluid silicone gel were tested: DermaCress, Alhydran, Lipikar and BAP Scar Care silicone gel respectively. TEWL reducing capacities and both absolute (AAH) and cumulative (CAAH) absolute added hydration were assessed using a Tewameter® TM300 and a Corneometer® CM825 at different time points for up to 4 h after application. RESULTS: We found an immediate TEWL increase in all the zones that underwent superficial abrasions by stripping. Controls remained stable over time, relative to the ambient condition. The mean percentage reduction (MPR) in TEWL kept increasing over time with Alhydran and DermaCress, reaching a maximum effect 4 h after application. Silicone gel reached maximal MPR almost immediately after application and only declined thereafter. The silicone gel never reached the minimal MPR of Alhydran or DermaCress. Hydration capacity assessed through CAAH as measured by the Corneometer was significantly less with silicone gel compared to the moisturizers. Compared to silicone gel Lipikar provided similar occlusion and the improvement in hydration was highly significant 4 h after application. CONCLUSION: Based on the results of both our previous research and this study it is clearly demonstrated that the occlusive and hydrative effect of fluid silicone gel is inferior to the moisturizers used in our center. Lipikar hydrates well but is less suitable for scar treatment due to the lack of occlusion. A well-balanced occlusion and hydration, in this study only provided by Alhydran and DermaCress, suggests that moisturizers can be used as a scar hydration therapy that replaces silicone products, is more cost-effective and has a more patient-friendly application.

Enzymatic debridement: past, present, and future.

INTRODUCTION: Early surgical debridement of the deep second and third-degree burns is still the standard of care (SOC) to prepare the wound bed for skin grafting. However, this technique has some drawbacks that explain the growing interest in enzymatic debridement as an alternative. In this article, we provide a historic overview as well as the current state-of-the-art and future prospective of this type of non-surgical debridement. MATERIALS AND METHODS: A narrative review of the available literature was conducted using a systematic search. RESULTS: A total of 32 articles were included. The only enzyme mixture still used nowadays for burn eschar removal is bromelain-based. There is increasing evidence that this type of enzymatic debridement is a powerful tool to selectively remove the eschar in deep burns, thereby reducing the need for autologous skin grafting compared to surgical SOC. Moreover, off-label use of enzymatic debridement with NexoBrid® (facial, pediatric, and >15%TBSA burns) has proven to be effective and safe. CONCLUSION: There is increasing evidence that bedside administered NexoBrid®, preferably under regional anesthesia, is a powerful tool for selective burn eschar removal. However, the clinical wound bed evaluation post-NexoBrid® procedure in relation to the optimal treatment decision-conservative treatment vs. surgery-is not yet completely elucidated. More high-quality prospective clinical trials are necessary to compare enzymatic debridement of objectively confirmed deep burns with the current standard treatment and assess the effectiveness of the eschar removal, the need for surgery, the healing time of such wounds, and the long-term scar quality.

The use of fluid silicone gels in the prevention and treatment of hypertrophic scars: a systematic review and meta-analysis.

BACKGROUND: Silicone products, either as a sheet or in fluid form, are universally considered as the first line therapy in the prevention and treatment of hypertrophic scars and keloids. However, the study results have been questioned by different authors and there has never been a large systematic synopsis published on the efficacy of fluid silicone gels. This systematic review aims to elucidate the available evidence of the results obtained by fluid silicone gels and present a complete and comprehensive overview of the available literature as well as a meta-analysis of the pooled data. METHODS: A systematic search for articles concerning the use of silicone gel in the treatment and prevention of scars was performed on 3 different databases (Pubmed, Embase and Cochrane library) according to the PRISMA statement. Only RCT's were included. Qualitative assessment was done by 2 separate reviewers using the Cochrane risk of bias (RoB 2) assessment tool. Revman 5.4.1 software was used for meta-analysis. RESULTS: The search yielded 507 articles. Two articles were identified through other sources. After deduplication and removal of ineligible records, 340 records were screened on title and abstract. Full text screening was done for 23 articles and ultimately 18 articles were included. A meta-analysis comparing fluid silicone gel to no treatment or placebo gels was conducted. CONCLUSION: Studies on the effects of liquid silicone gels on hypertrophic scars are numerous and this systematic review shows that the use of liquid silicone gels is associated with both a prophylactic and a curative effect on scars. However, a considerable amount of the available 'high evidence' trials are at a high risk for bias and it is uncertain whether or not the effects of silicone gels are comparable to silicone sheets and if the additional components present in many silicone gels are partially responsible for their scar improving capacity.