Biomimetic coatings and negative pressure wound therapy independently limit epithelial downgrowth around percutaneous...

Biomimetic material coatings and negative pressure wound therapy (NPWT) have been shown independently to limit the epithelial downgrowth rates in percutaneous devices. It was therefore hypothesized that these techniques, in combination, could further limit the clinically observed epithelial downgrowth around these devices. In this study, we evaluated the efficacy of two biomimetic coatings, collagen and hydroxyapatite (HA), to prevent downgrowth when used with continuous NPWT. Using an established single-stage surgical protocol, collagen (n = 10) and HA (n = 10) coated devices were implanted subdermally on the back of hairless guinea pigs. Five animals from each group were subjected to continuous ~90 mmHg NPWT. Four weeks post-implantation, animals were sacrificed, and the devices and surrounding tissues were harvested, processed, and downgrowth was computed and compared to historical porous titanium coated controls. Data showed a significant reduction in downgrowth in NPWT treated animals (p ≤ 0.05) when compared to the untreated porous titanium controls. HA coated devices, without the NPWT treatment, also showed significantly decreased downgrowth compared to the untreated porous titanium controls.