PDLCS Bioactivity Evaluation for Instantaneous High Temperature in Thermo-plasticized Obturation.

There has been great interest in the application of thermo-plasticized obturation in endodontic treatment. During practical clinical application, the curative effect of root canal therapy seriously depends on the heating time and temperature. Herein, we comprehensively analyze the instantaneous high temperature induced by long time heating. The in vitro effect of temperature on periodontal ligament stem cells (PDLSCs) is detailed investigated and the safe heating time is confirmed. Our results indicate that 6 s of heating treatment at 200°C causes evident damage to the osteogenic differentiation, proliferation and migration ability of PDLSCs, while 4 s of heating treatment at 200 °C is uninjurious to the above mentioned biological behavior of PDLSCs compared to the control group in vitro. To apply thermo-plasticized obturation in clinical, we recommend that when the heat source is fixed at 200 °C, 4 s of activation will be safe, while 6 s of activation is risky for both doctor and the patient.