Effect of loss of bite force on interleukin-1beta expression in rat periodontium.

OBJECTIVE: To study the expression of interleukin-1beta(IL-1beta) in the fibroblasts and osteoblasts in the periodontal ligament cells(PDLC) of normal rats and rats with loss of bite force, to explain the molecular mechanism of periodontium remodeling. METHODS: Rat models of lost bite force were established using Wistar rats. The changes in the histological morphology of the periodontium and the expression of IL-1beta in the PDLC and osteoblasts were observed in both normal rats and the rat models using HE staining and immunohistochemistry techniques. RESULTS: In rat models of lost bite force, the periodontal ligament structure appeared to be disorganized and absorption occurred in the alveolar bone. The expression level of IL-1beta in the PDLC and osteoblasts was significantly enhanced in comparison with that in the normal rats, as demonstrated by immunohistochemical study. CONCLUSION: Loss of bite force may induce structural disorganization of the periodontal ligament and absorption in the alveolar bone, and the expression level of IL-1beta in PDLC and osteoblasts show significant elevation, indicating that the changes in histological morphology is closely coordinated with the functional changes in the periodontium.