In vivo biocompatibility, vascularization, and incorporation of Integra® dermal regenerative template and flowable wound matrix.

Integra® matrix wound dressing (MWD) is used for the reconstruction of full-thickness skin defects. For the treatment of complex wounds, this dermal substitute is available as a flowable wound matrix (FWM) of identical composition. To clarify whether variations in sample preparation and consistency affect the biocompatibility and tissue incorporation, we herein compared MWD and FWM. The matrices were characterized using scanning electron microscopy and histology. Moreover, they were implanted in mouse dorsal skinfold chambers to analyze their in vivo performance over 2 weeks. Scanning electron microscopy showed a planar surface of MWD whereas FWM presented an irregular, fissured morphology. However, histology of the two matrices revealed an identical fiber thickness, fiber length, and interfiber distance. Repetitive stereo-microscopy and immunohistochemical analyses of MWD and FWM showed a comparable epithelialization of the implants in the dorsal skinfold chamber model. At day 14, both matrices exhibited a low collagen content and microvessel density. Moreover, they were infiltrated by a high number of myeloperoxidase (MPO)-positive neutrophilic granulocytes and a lower number of MAC387-positive macrophages and CD3-positive lymphocytes. These findings demonstrate that differences in preparation and consistency do not affect the tissue response to MWD and FWM, indicating a comparable regenerative capacity in wound healing.