The effect of materials used in pulpal treatments in children on deciduous pulp stem cells

Objective: The aim of this study is to examine the cytotoxic, genotoxic, and cell migration effects of bioactive materials used in vital pulp treatments in children, such as MTA (Angelus, Brazil), Biodentine (Septodent, France), Bio-C Repair (Angelus, Brazil), Neoliner LC (Nusmile, USA), Theracal PT (Bisco, USA), and antibiotic pastes used in lesion sterilization and tissue repair (LSTR) and regenerative endodontic treatment on stem cells from human exfoliated deciduous teeth (SHED). Materials and Methods: The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was used to assess the cytotoxic effects of the materials on SHED cells, the Comet assay (single-cell gel electrophoresis) was performed to evaluate genotoxicity, and the Wound Healing scratch assay was applied to examine the effects on cell migration. For the MTT assay, test materials prepared according to the manufacturers' instructions were added to 96-well cell culture plates. The resulting extracts were diluted appropriately (1%, 5%, 10%) and applied to SHED cells for cytotoxicity testing. For the Comet assay, cells exposed to test materials were spread onto slides coated with agar and incubated in lysis solution. Electrophoresis was performed at 25 volts for 20 minutes. Slides were then analyzed under a fluorescent microscope for genotoxicity. For the Wound Healing assay, 3x10^5 cells per well were seeded into 6-well plates and allowed to grow. Once cells reached 100% confluence, a cell-free area was created in each well, and test groups were treated. Images were captured at 0 and 24 hours to evaluate cell migration. Statistical analysis was performed using the SPSS software. Results: According to the MTT test results, 1% Biodentine showed a statistically significant increase in cell viability compared to the control group (p<0.01). Other materials demonstrated similar cell viability to the control. At 5% dilutions, significantly higher cell viability compared to the control was observed with Theracal PT (p=0.01), NeoLiner LC (p=0.02), and Bio-C Repair (p=0.04). At 10% dilutions, Theracal PT (p=0.002) and NeoLiner LC (p=0.024) demonstrated significantly higher cell viability compared to the control group. There was no significant difference in cell viability between the control group and the other materials (p>0.05). In the MTT test for antibiotic pastes, the 5% dilution of triple antibiotic paste showed a significant reduction in cell viability compared to the control (p=0.001). In the 10% dilutions, a reduction in cell viability was observed in the double antibiotic paste compared to the control, but this was not statistically significant (p>0.05). The reduction in cell viability for the triple antibiotic paste was statistically significant (p=0.001). According to the Comet test results, MTA showed genotoxicity similar to the control group. Biodentine and NeoLiner LC showed similar results to each other but had higher damage rates compared to the control. The highest damage rates were observed with Bio-C Repair and Theracal PT (p<0.001). The Wound Healing assay indicated that all materials promoted cell migration, as evidenced by higher values compared to the control group. Conclusion: According to the MTT assay results, all bioactive materials promoted an increase in SHED cell proliferation. The highest proliferation was observed with 1% Biodentine. All concentrations of antibiotic pastes, except the 1% concentration, caused over 30% cell death, indicating cytotoxic effects. According to the Comet test results, Bio-C Repair and Theracal PT had significantly higher genotoxic indices and damaged cell counts compared to the other materials (p<0.05). More detailed studies are needed on these materials in the future. The Wound Healing assay indicated that all bioactive materials promoted cell migration. Keywords: Bioactive materials, Genotoxicity, Cytotoxicity, Stem cells from human exfoliated deciduous teeth (SHED).