Shows the reaction of Human Periodontal Ligament Fibroblasts to AHPlus and GuttaFlow stained with Phallacidin/DAPI and Calcein-homodimer. DAPI-stains the cell core blue and Phallacidin counterstains the cytoplasm green. The intact membrane of live cells is not permeable for Ethidium homodimer. a) In the AHPlus group cells were altered in shape and appeared round without cytoplasm brances, Phallacidin/DAPI-staininig 100 ×, magnification, scale bar = 100 μm. b) shows damaged cells in close proximity to AHPlus indicated by the presence of red color in cell cytoplasm, Calcein-homodimer-staininig, 100× magnification, scale bar = 100 μm. c) cells in the GuttalFlow group were found to built a three dimensional network, reaching to deeper regions of the material. Phallacidin/DAPI-staininig 200 × magnification, scale bar = 100 μm. d) shows cells on the surface of GuttaFlow displaying a brightly luminating green color as a sign of an intact metabolism and intact cell cytoplasm Calcein-homodimer-staininig, 200 × magnification, scale bar = 100 μm.