Immunocytochemical detection of apoptosis in human odontoblasts

Abstract

Eur J Oral Sci /998. 106 (supp/1 ). 384 387 P,.inted in UK. All rights resen ed Immunocytochemical detection of apoptosis in human odontoblasts Franquin J-C. Remusal M, Abou Hashieh I, Dejou J: lmmunocylochemical detection of apoptosis in human odontoblasts. Eur J Oral Sci 1998: 106 (suppl 1): 384 387. Eur J Oral Sci , 1998Pulpal chamber ize decrea es on ageing due to primary and secondary dentin deposition . This work was designed to find out the con equences of thi pulp chamber reduction on odontobla t number and distribution . Twenty-one healthy human premolars were equally divided into three groups from II-, 12.5-and 14-yr-old adolescents, respectively). The external and the internal perimeters of dentin were recorded on vestibulo-lingual sections, from buccal to lingual cemento-enamel junction using an image analysis system . Nuclei of the odontoblasts were recorded on 12 automatically selected fields. On nine erupted premolars (3 teeth from each II-, 12.5-and 14-yr-old patients) , apoptosis wa detected by confocal micro copy u ing a modification of the original TUNEL method . Apoptotic cell were labeled in central pulp fibroblasts , perivascular endothelial cells, and in odontoblasts. When the pulp volume decreases due to primary dentin production, the decrease of the surface available for odontobla t is compen a ted for by a multilayer distribution of cells. Secondary dentin deposition, associated with odontoblasts reorganization in a single layer, results in a hyperbolic decrease of the odontoblasts number. This decrease seems to result from a programmed cell death, which eliminates half of the odontoblasts over a 4-yr period .

Apoptosis in developmental and repair-related human tooth remodeling: A view from the inside

“…Continuous dentin deposition progressively decreases both the volume occupied by the pulp fibroblasts and the dentin/odontoblast interface. The only study dealing with this physiological event has shown that massive odontoblast apoptosis occurs during a 4-year period [15]. To confirm these previous studies we have measured the number of odontoblasts in a given surface of 10, 11, 12.5 and 14 year-old premolars.…”

“…In another experimental set, cavity preparations were performed as previously described in 17 premolars of 11 to 12 year-old patients [15], while 4 intact premolars were used as a control. A dental product (IRM) was used to restore the cavities, in conjunction with a calcium hydroxide lining material (Dycal, Dentsply, Milford, DE, USA).…”

“…The external and internal dentin perimeters were measured as described previously [15]. On the same sections, nuclei of the odontoblasts per 100 μm were recorded in 12 automatically pre-selected fields at the cement-enamel junction area.…”

“…On the same sections, nuclei of the odontoblasts per 100 μm were recorded in 12 automatically pre-selected fields at the cement-enamel junction area. Statistic analysis was performed as described previously [15].…”

“…However, the dental pulp volume decreases gradually on ageing due to the continuous production of dentin matrix by odontoblasts. This age-related pulp chamber reduction is associated with the elimination of a certain number of odontoblasts by apoptosis [14,15]. In pathological conditions involving mild carious lesions, odontoblast activity is stimulated to elaborate a reactionary dentin [16][17][18][19][20].…”