The human periodontal membrane: focusing on the spatial interrelation between the epithelial layer of Malassez, fibers, and innervation.

The purpose of the present study was to map the spatial interrelation of fibers, peripheral nerves, and epithelial layer of Malassez in human periodontal membrane in areas close to the root surfaces.Four healthy permanent teeth extracted from four patients during puberty due to orthodontic treatment planning were analyzed. The extracted teeth, fixed in 4% neutral buffered formaldehyde for 5 days, were decalcified in 0.5 M EDTA. Paraffin blocks were sagittally cut in 5 microm thick serial sections and mounted on Superfrost Plus microscope slides. For survey, every fifth slide was stained with Alcian Blue/Van Gieson. Immunohistochemical reactions: Cytokeratin (wide spectrum screening) for epithelium, anti-vimentin for fibers, and anti-neuronal nuclei (NeuN) for innervation.The study indicates that the epithelial layer of Malassez is a border between different fiber morphologies and innervation patterns. Innervation is identified predominantly in the periodontal layer with tightly packed fibers close to the root surface.It is suggested that the genetic composition of the epithelial layer of Malassez in the periodontal membrane may be the key to understanding the different functions of the periodontal membrane and also the individual differences of these functions.