The Cytotoxic Effect of Cysteamine and its Combinations with Various Endodontic Intracanal Medications on Fibroblast Cells; in Vitro Study

Abstract

Abstract Objective: This study was established to assess cysteamine’s cytotoxic effect alone and in combination with various intracanal medications on fibroblast cells. Because the biocompatibility of intracanal medication is considered one of the main factors that affect the selection of specific medication for usage near vital periodontal tissues. Materials and Methods: All tested medications were prepared in a solution form. Cysteamine preparation was prepared at 200mg/ml concentration in distilled water. Chlorhexidine Cysteamine combination was prepared by dissolving 10 mg/ml of Cysteamine in CHX. Calcium hydroxide Cysteamine combination was prepared by dissolving 10 mg/mL of Cysteamine in a saturated solution of CaOH. TAP Cysteamine combination was prepared by dissolving 10 mg/mL of Cysteamine in TAP. BHK cells were seeded in well-microtiter plates. The testing materials were filtrated using a 0.22 μm syringe filter. BHK-21 cells precultured well plates were treated with descending 12-fold serially diluted medications at 37 °C for 24 h. Residual living cells were treated with 25 μl of MTT dye. MTT was discarded, then Dimethyl sulfoxide was added as 50 μl/well. The absorbance was conducted at 570nm. The mean optical density and 50 % cell growth inhibition (IC50) were calculated. The significance level was set at p≤0.05. Results: Viability % and IC50 results showed that TAP Cysteamine combination had the lowest cytotoxicity level compared to other intracanal combinations followed by Cysteamine and the highest cytotoxicity was with Chlorhexidine Cysteamine combination. Conclusion: TAP Cysteamine combination was the safest drug compared to other drug combinations with cysteamine, so it needs more research to detect its acceptance with stem cells and its effect on defense mechanisms during healing.