Effects of silicone-based gels containing allantoin, dexpanthenol and heparin on hypertrophic scarring in the rabbit ear model

Silicone-based formulations are extensively used for the management of hypertrophic scars. Although the exact mechanism of action is still unknown, it has been postulated that some occlusion and hydration of the stratum corneum with subsequent cytokine-mediated signaling from keratinocytes to dermal fibroblasts is involved in its antiscarring effects. In this study, the effectiveness of silicone-based gels containing allantoin, dexpanthenol, and heparin was evaluated for improving the healing of hypertrophic scars. It was found that silicone-based gels showed remarkable improvements in hypertrophic scar healing and low amounts of skin pigmentation in the rabbit ear model compared with the nontreated control or base alone. Furthermore, the histopathological and histomorphometrical profiles of three different formulations containing 1%, 5%, and 20% silicone contents exhibited marked or significant decreases in the scar elevation index, anterior skin and epithelial thicknesses, inflammatory cells, vessels, collagen disorganization, and fibroblasts compared with nontreated control hypertrophic scars. Therefore, these results indicate that silicone-based gels containing heparin, allantoin, and dexpanthenol could be promising formulations for the healing of hypertrophic scars.