IADR Abstract Archives
Calcium-titanates Increase In Vitro Dental Pulp Cell Viability
Objectives: Titanates are water insoluble ceramic particles (1-20 μm) of titanium oxide that bind multivalent cations. In vitro biocompatibility studies have reported varying degrees of cellular toxicity to titanates depending on the cell type. In addition, toxicity has been augmented by titanate-complexed cations. The aim of this study was to measure the toxicity of titanate-calcium complexes to dental pulp cells (DPCs).
Methods: DPCs were plated in 96-well format (n=8) at cell densities of 5,000 (low) or 30,000 (high) cells/cm2 for 24 h prior to treatment with monosodium titanates (MST, 0-200 mg/L) without ('native', control) or complexed with calcium (MST-Ca(II)). Cellular metabolic activity was used to estimate cellular viability with the commercially available CellTiter-Blue® assay (resorufin fluorescence, 560nm excitation/590nm emission). Differences in metabolic activity were identified using two-sided Student's t-tests with a p-value < 0.05 considered significant.
Results: At a low initial cell density, native MST treatment resulted in 67% viability compared to untreated controls (100%, p<0.05). The decrease in viability was significant at an MST concentration of 25 mg/L and reached a plateau at 50 mg/L, congruent with previously reported studies using other cell types. The addition of calcium complexed with MST increased cell viability such that there was no statistical significance between untreated cells and cultures treated with 200 mg/L MST-Ca(II). At high initial cell density, cell viability decreased to 76% compared to controls (p<0.05) and was not significant until 100 mg/L MST. The addition of Ca(II) complexed with the MST increased cell viability and stimulated cell proliferation, with a statistically significant increase in viability (116%, p<0.05) at an MST-Ca(II) concentration of 25 mg/L; viability returned to control levels at 200 mg/L.
Conclusions: MST is slightly toxic to DPCs but can be used to deliver Ca(II) to cultures, increasing cell viability.
Methods: DPCs were plated in 96-well format (n=8) at cell densities of 5,000 (low) or 30,000 (high) cells/cm2 for 24 h prior to treatment with monosodium titanates (MST, 0-200 mg/L) without ('native', control) or complexed with calcium (MST-Ca(II)). Cellular metabolic activity was used to estimate cellular viability with the commercially available CellTiter-Blue® assay (resorufin fluorescence, 560nm excitation/590nm emission). Differences in metabolic activity were identified using two-sided Student's t-tests with a p-value < 0.05 considered significant.
Results: At a low initial cell density, native MST treatment resulted in 67% viability compared to untreated controls (100%, p<0.05). The decrease in viability was significant at an MST concentration of 25 mg/L and reached a plateau at 50 mg/L, congruent with previously reported studies using other cell types. The addition of calcium complexed with MST increased cell viability such that there was no statistical significance between untreated cells and cultures treated with 200 mg/L MST-Ca(II). At high initial cell density, cell viability decreased to 76% compared to controls (p<0.05) and was not significant until 100 mg/L MST. The addition of Ca(II) complexed with the MST increased cell viability and stimulated cell proliferation, with a statistically significant increase in viability (116%, p<0.05) at an MST-Ca(II) concentration of 25 mg/L; viability returned to control levels at 200 mg/L.
Conclusions: MST is slightly toxic to DPCs but can be used to deliver Ca(II) to cultures, increasing cell viability.