Effect of dentine conditioning with phytic acid or etidronic acid on growth factor release, dental pulp stem cell migration and viability

Abstract

Aim To investigate the effect of several chelating solutions on transforming growth factor (TGF-beta) release from dentine discs and their subsequent impact on cellular behaviour. Methodology Human dentine discs were prepared with a standardized diameter and disinfected using 1.5% NaOCl for 5 min. The dentine discs were then exposed to 17% ethylenediaminetetraacetic acid (EDTA), 1% phytic acid (IP6), 9% etidronic acid (HEDP) or distilled water (DW). The release of transforming growth factor (TGF-beta) was quantified using ELISA. The proliferation of dental pulp stem cells (DPSCs) on the conditioned dentine discs was analysed using an MTT assay, and the cell morphology was observed by SEM. Migration of DPSCs towards the conditioned dentine discs was measured using a Transwell assay. Data for cell proliferation and migration were analysed using two-way analysis of variance with a Bonferroni post hoc test; a Kruskal-Wallis test was used for analysing TGF-beta release. Results Both HEDP and IP6 treatment triggered TGF-beta release and cell migration. The greatest TGF-beta release was observed after HEDP treatment as compared with EDTA and DW but there was no significant difference between the groups. In terms of cell migration, HEDP was more effective than EDTA (P < 0.05) whilst IP6 was similar to EDTA. Cell proliferation significantly increased with time after EDTA, DW and IP6 treatment (P < 0.05), whereas HEDP treatment did not induce cell proliferation (P > 0.05). Conclusions IP6 and HEDP were effective chelating agents on TGF-beta release, and cell migration was as effective as EDTA.