Promotive effects of a silk film on epidermal recovery from full-thicknessskin wounds

We examined the effects of the transparent fibroin film (silk film) on full -thickness skin wounds. Full-thickness dermatotomies (15 mm x 9 mm) were pr epared on the dorsal wall of CRJ:CD-1 nu/nu (ICR nu/nu) mice. The area of t he wounds dressed with silk film was reduced to 10% of that made by the der matotomy 14 days after the dermatotomy and were covered with regenerated ep idermis 21 days after the dermatotomy, In contrast, less recovery and epide rmal regeneration were found 14 days after dermatotomy in the wounds dresse d with a conventional hydrocolloid dressing (Duro Active). Furthermore, onl y partial incomplete epidemal growth was obtained 21 days after dermatotomy , Most importantly, the healing time of wounds dressed with silk film was 7 days shorter than those dressed with DuoActive dressing. The silk film sho wed an almost similar or slightly better promotive effect as the lyophilize d porcine dermis (Alloask D), which Is used as a dressing for burns, ulcers , and decubitis, Histologic findings revealed that there was greater collag en regeneration and less inflammation and neutrophil-lymphocyte infiltratio n of the wounds dressed with silk film than with DuoActive dressing. It is clear that regeneration of the epidermis and dermis of the wound beds cover ed with silk film was faster than with DuoActive dressing. Finally, silk fi lm is easily obtainable, sterilizable, and transparent, and it allows easy observation of tissue recovery. Therefore, silk film offers advantages over other dressings and may be clinically useful for wound treatment.