AbstractThe periodontal ligament is a crucial tissue that provides support to the periodontium. Situated between the alveolar bone and the tooth root, it consists primarily of fibroblasts, cementoblasts, osteoblasts, osteoclasts, periodontal ligament stem cells (PDLSCs), and epithelial cell rests of Malassez. Fibroblasts, cementoblasts, osteoblasts, and osteoclasts are functionally differentiated cells, whereas PDLSCs are undifferentiated mesenchymal stem cells. The dynamic development of these cells is intricately linked to periodontal changes and homeostasis. Notably, the regulation of programmed cell death facilitates the clearance of necrotic tissue and plays a pivotal role in immune response. However, it also potentially contributes to the loss of periodontal supporting tissues and root resorption. These findings have significant implications for understanding the occurrence and progression of periodontitis, as well as the mechanisms underlying orthodontic root resorption. Further, the regulation of periodontal ligament cell (PDLC) death is influenced by both systemic and local factors. This comprehensive review focuses on recent studies reporting the mechanisms of PDLC death and related factors.