bcl-2, p53, and MIB-1 in human adult dental pulp

Little is known about the renewal of some groups of cells in dental pulp, a nd the occurrence and significance of physiological cell death in dental pu lp is not yet understood. The possibility of odontoblast disappearance by a poptosis has been proposed, and the presence of apoptotic cells in the rat and human odontoblastic and subodontoblastic layers has been recently descr ibed. bcl-2 and p53 are proteins involved in the apoptotic pathway, whereas MIB-1 is a proliferating cell marker. The aim of our study was an immunohi stochemical evaluation of bcl-2, p53, and MIB-1 in healthy normal pulps of young human subjects. With bcl-2 immunostaining, some positive cells were f ound in the odontoblastic and subodontoblastic layers, whereas with MIB-1, only a few stromal cells were positive, and all odontoblasts were consisten tly negative. No cells were positive to p53. The bcl-2 immunoreactivity of the cells of the odontoblastic and subodontoblastic layers could help to ex plain the presence of apoptotic cells found in these regions.