Influence of resinous monomers on the differentiation in vitro of human pulp cells into odontoblasts

Abstract

Odontoblasts are highly differentiated postmitotic cells, which under pathological conditions such as carious lesions and dental injuries may degenerate and be replaced by other pulp cells. A recent work showed that this physiological event can be reproduced in an in vitro assay system. The purpose of the present study was to evaluate the effects of resinous monomers on odontoblast differentiation in vitro. Pulp cores from extracted human third molars were cultured with beta-glycerophosphate (2 mM) and used to evaluate the effects of TEGDMA, HEMA, UDMA, and Bis-GMA on the differentiation of pulp fibroblasts into odontoblasts. The effect of the monomers was studied by evaluating the expression of several odontoblast specific genes. In the absence of monomers, mineral nodule formation was observed. Pulp cells contributing to the nodule formation synthesized type I collagen, osteonectin, and dentin sialoprotein (DSP). In addition, Fourier transform infrared microspectroscopy showed that the mineral and organic composition of the nodules were characteristic of dentin. When the monomers were added at nontoxic concentrations, the effects of HEMA and Bis-GMA were more evident than that of TEGDMA and UDMA on collagen 1, osteonectin, and DSP expression. However, all monomers significantly decreased DSP expression and completely inhibited the mineral nodule formation.

TEGDMA Reduces Mineralization in Dental Pulp Cells

“…Moreover, concentrations as low as 10 µM of the monomers HEMA and TEGDMA reduced the protein levels of collagen I, osteonectin, and DSP in human pulp cells after 4 wks. Signs of acute cytotoxicity were not detected (About et al, 2002). Here, the levels of the internal standards GAPDH and betaactin slightly decreased at low TEGDMA concentrations after short exposure, and cell viability and proliferation remained stable up to 14 days.…”

N-acetylcysteine protects dental pulp stromal cells from HEMA-induced apoptosis by inducing differentiation of the cells

“…Human dental pulp stromal cells were obtained from freshly extracted third molars and were cultured as described above [5].…”

“…However, the mechanisms by which these materials cause adverse effects in patients have not been completely elucidated. Resin monomers such as HEMA (2-hydroxyethyl methacrylate) and TEGDMA (triethyleneglycol dimethacrylate) are shown to influence the differentiation of human pulp cells into odontoblasts [5]. We have shown previously that HEMA induces apoptosis in different cell types [6] and also in DPSCs and in odontoblast like cells.…”

An Overview to the Cytotoxicity of Resin Based Dental Materials

“…54 Ayrıca rezin monomerlerin kök hücrelerin de dahil olduğu pulpa kaynaklı hücrelerin odontojenik farklılaşma ve mineralizasyon süreçlerinde gecikmeye neden olduğu bildirilmiştir. [55][56][57][58] Rezin monomerler çevresel stres kaynağı oluşturarak kompleks hücresel iletişimi ve sinyal iletim yolağını bozmaktadır. 59 Normal koşullarda hücrede oksidatif stres oluşturan, hidrojen peroksit, süperoksit anyonları ve hidroksil radikalleri içeren reaktif oksijen türleri (ROS) ile bunların salım ve kontrolünü sağlayan antioksidan sistemleri arası denge mevcuttur.…”