Cell proliferation in developing human dental pulp A combined flow cytometric and immunohistochemical study

Abstract

Information concerning cell proliferation and differentiation in dental pulp may be important to understand tooth response to exogenous stimuli. Since few data concerning human dental pulp are available, we have investigated the growth fraction and the localization of proliferating cells in pulp tissue of third molars of young adult human males and females, using flow cytometry and immunohistochemistry. Flow cytometric analysis demonstrates a low proliferative activity of pulp tissue that appears to be confined to radicular pulp, as revealed by immunohistochemical detection of proliferating cells. No polyploid or aneuploid cell populations could be identified, and G2-blocked cells, if any, represented a negligible cell population. Odontoblasts, cells of the sub-odontoblastic layer, and cells of coronal pulp were found to be not proliferating under normal conditions. These data provide the basis for future investigations on proliferative activity and regenerative potentiality of human pulp cells in experimental and clinical situations.

Direct Pulp Capping with Mineral Trioxide Aggregate: An Immunohistologic Comparison with Calcium Hydroxide in Rodents

“…Immunohistologic analysis revealed that the turnover rate of cells in healthy pulp tissue is low (20,21) because odontoblasts do not undergo mitosis (22,23). Cavity preparation alone leads to an increase of the mitosis rate, which results in a proliferation of cells in the direction toward the damaged pulp tissue (22).…”

The relationship between the termination of cell proliferation and expression of heat‐shock protein‐25 in the rat developing tooth germ

“…It has been suggested that anti‐Ki67 immunoglobulin is more appropriate for assessing the proliferative activity than anti‐PCNA immunoglobulin, because PCNA may be detected in cells at the G0 phase (14). In the field of tooth development, Ki67 monoclonal antibody (mAb) has been used to identify the proliferating cells of developing human pulpal cells and dental epithelial cells in mouse incisors (15, 16). Analysis of cell kinetics by BrdU labeling and Ki67 staining indicates that the number of Ki67‐positive cells is larger than that of BrdU‐labeled cells, although the number of both BrdU‐labeled and Ki67‐positive cells varies, depending on the interval between the intraperitoneal injection of BrdU and the sacrifice of animals (16).…”

Regenerative capability of dental pulp cells after crown fracture

“…Casasco et al. (28) reported that approximately 90% of dental pulp tissue is in the G0/G1 phase, although p57 mRNA expression in the experimental group was higher than in the control group, which means that the tooth fracture causes stem cells in the dental pulp to proliferate through the cell proliferation cycle.…”