Method: The GPM was produced via electrospinning. The gelatine fibres of the GPM were in situ crosslinked during the spinning process. Interactive organotypic cell systems were established by cultivating human gingival keratinocytes (HGK) on the denser side of the GPM and human gingival fibroblast (HGF) on the less dense side. The cell compartments were analysed by immunohistochemistry and scanning electron microscopy (SEM). Additionally, the GPM was applied in a pilot minipig study, where the clinical wound healing was evaluated for a period of 4 weeks after operative procedure.
Results: SEM and actin / integrin fluorescence showed a typical morphology of HGF and HGK and visualised in addition cell adhesion to the fibres network. Deposited extracellular matrix was observed on HGF membrane that migrated into the fibre network. The HGK formed a stratified epithelial equivalent. Immunohistological analysis revealed tissue-specific distribution of vimentin in the connective tissue compartment and an increase of keratin 1/10 and involucrin expression over time in the epithelial equivalent. In addition, the suitability of this novel membrane for oral soft tissue regeneration was encouraged by a pilot study in the minipig model, where an almost complete epithelial wound closure was observed following a surgically-induced dehiscence.
Conclusion: Preclinical validation of the novel GPM by using organotypic interactive cell systems and the pilot minipig study suggested this membrane as promising and versatile medical device for treatment of oral soft tissue defects.