Currently, the exact pathomechanism

Currently, the exact pathomechanisms which lead to hypertrophic scarring are not yet completely understood. Various studies, like from Butzelaar et al. [1] or Sarrazy et al. [3]investigating the background of pathological scarring, observed several differences in the genesis of HS compared to the normal wound healing process. To summarize studyresults briefly, hypertrophic scarring is related to an prolonged inflammatory phasefollowed by pathological modifications of wound healing process such ashypercellularity, augmented neovascularization and excessive collagen production.Specific hypertrophic scar fibroblasts found in HS tissue show a greater expression ofTGF-β1, causing an overproduction of collagen. Furthermore, an imbalance of collagenproduction and collagenases (like matrix metalloproteinases, MMP) also occurs, leadingto a dysfunctional remodeling of granulation tissue and resultant hypertrophicscarring[1–4]. The complexity of the wound healing process may explain the currentPage 4 of 18Wound Repair and RegenerationManuscript under review - CONFIDENTIALThis article is protected by copyright. All rights reserved.5variety of treatment methods for hypertrophic scarring. Silicone products are an earlytreatment modality which have been used since 1980 [2]. Silicone products mayinfluence hypertrophic scarring by enabling constant hydration of the scar tissue as aconsequence of the applied silicone membrane. Another treatment method is theapplication of mechanical pressure to the scar surface via pressure garments todecrease blood and oxygen flow into the scar tissue, which may reduce cellularproliferation and prevent excessive scarring[4–6]. Other studies recommend the use ofmore invasive methods such as intralesional injections of corticosteroids,