Characterization of a new degradable polymer scaffold for regeneration of the dermis

Abstract

Full thickness skin wounds in humans heal with scars, but without regeneration of the dermis. A degradable poly(urethane urea) scaffold (PUUR), Artelon(R) is already used to reinforce soft tissues in orthopaedics, and for treatment of osteoarthritis of the hand, wrist and foot. In this paper we have done in vitro experiments followed by in vivo studies to find out whether the PUUR is biocompatible and usable as a template for dermal regeneration. Human dermal fibroblasts were cultured on discs of PUUR, with different macrostructures (fibrous and porous). They adhered to and migrated into the scaffolds, and produced collagen. The porous scaffold was judged more suitable for clinical applications and 4 mm Ø, 2 mm-thick discs of porous scaffold (12% w/w or 9% w/w polymer solution) were inserted intradermally in four healthy human volunteers. The implants were well tolerated and increasing ingrowth of fibroblasts was seen over time in all subjects. The fibroblasts stained immunohistochemically for procollagen and von Willebrand factor, indicating neocollagenesis and angiogenesis within the scaffolds. The PUUR scaffold may be a suitable material to use as a template for dermal regeneration.

Use of Artelon^® Cosmetic in soft tissue augmentation in dentistry

“…25 Swelling and warmth were noted when the Artelon scaffold was used for regeneration of the dermis, and low-grade inflammation with minor turbid secretion and itching were also noted. 12 It was also seen that the skin covering the scaffolds partly contracted, resulting in protrusion of the scaffold at all study sites. 12 Most of the total tissue volume gained was lost at 3 months in one case when an Artelon graft was use for soft tissue augmentation in dental implant treatment.…”

“…20 Ideally, materials should be slowly biodegraded to elicit a minimal host response as well as provide long-term support during the tissue remodeling process. 12 The Artelon graft is reported to be degraded by hydrolysis, and this material may have a degradation time in vitro of more than 4 years. 11 …”

“…11,12 Scaffolds of the various urethanes are prepared either by packing of fibers or by a solvent casting/particle leaching process. 12 Fibers are formed by extrusion of a 30% w/w polymer solution through a spinneret submerged in a coagulating bath containing hot water. Artelon may be made into different macroscopic structures, such as porous and fibrous forms, and the porous scaffold was reported to be more promising for clinical application.…”

“…12 Smaller numbers of inflammatory cells are seen after 8 weeks when compared with 2 weeks. The biocompatibility of polyurethane has been compared with that of polystyrene and titanium, and polyurethane induced the lowest capsule formation after both 7 and 21 days.…”

“…15 Long-term clinical data, animal data, and biopsy specimens have shown excellent biocompatibility with surrounding tissue without any chronic inflammatory response or multinuclear giant cell formation over a follow-up period of up to 2 years. 12 However, it has been reported that foreign body multinuclear giant cells were seen at histologic evaluation, and it was suggested that slowly degrading polyurethane may present a large unphagocytosable object, and a rough surface topography may favor multinuclear giant cell attachment to the surface. 8 Artelon is reported to assist the building of new tissue by supporting volume and providing a scaffold for tissue ingrowth.…”