Proliferative activity in the juxtaradicular human periodontal ligament

The aim of the present study was to evaluate cell proliferation, assessed by MIB 1, with respect to the type and the distribution of proliferating cells in the healthy juxtaradicular periodontal ligament (PDL) from completely formed human teeth. Immunohistochemical markers against vimentin, CD68 and S-100 were used to characterize cell type. The applicability of the immunohistochemical method on explants of human PDL was also evaluated. The results indicated that under physiological conditions, the majority of the proliferating cells in the PDL were mesenchymal cells predominantly located paravascularly in the middle third of the PDL. Furthermore, MIB 1 reacting with the Ki-67 antigen together with the avidin-biotin-complex technique was proved to be an efficient marker of cell proliferation in explants of human PDL.