Mode of cell death of co-cultured dental mesenchymal stem cells following exposure to endodontic irrigating solutions


  • Eshagh Ali Saberi Department of Endodontics, Faculty of Dentistry, Oral and Dental Diseases Research Center, Zahedan University of Medical Sciences, Zahedan, Iran
  • Narges Farhad Mollashahi Department of Endodontics, Faculty of Dentistry, Oral and Dental Diseases Research Center, Zahedan University of Medical Sciences, Zahedan, Iran
  • Mahboobe Ahmadi post graduate student, Zahedan University of Medical Sciences, Zahedan, Iran
  • Arezoo Pirhaji assistant Professor, Department of Endodontics, Faculty of Dentistry, Zahedan University of Medical Sciences, Zahedan, Iran



Co-culture, Apoptosis, Necrosis, Irrigants, Cells, Cultured.


Aims:  This in vitro study aimed to determine the mode of cell death of co-cultured  dental mesenchymal stem cells following exposure to different irrigating solutions.

Methods and Material: Mesenchymal stem cells of the apical papilla (SCAPs) and periodontal ligament stem cells (PDLSCs) were isolated from the periapical region of a third molar of an 18-year-old patient and cultured.  Adequate number of cells in each well, 6-well plate inserts were placed over the wells. The cells were then randomly exposed to 17% ethylenediaminetetraacetic acid (EDTA), 1.5% sodium hypochlorite (NaOCL), 2% chlorhexidine (CHX) and saline. After 1, 5, and 10 minutes cells were trypsinized and underwent flow cytometry. Apoptotic and necrotic cells were quantified. Data were analyzed using the One-way ANOVA and Tukey’s post-hoc test. 

Results: With increasing exposure time, cell viability is decrease and the mode of cells death was necrosis in CHX and NaOCL groups and necrosis plus late apoptosis in 1 and 10 minutes  in EDTA group.

Conclusion: Maximum cell death occurred following exposure to EDTA while minimum cell death occurred following exposure to CHX. Necrosis was the dominant mode of cell death in all groups. 



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Mechanisms of Oral Disease