Experimental Model of Ligature-Induced Periodontitis in C57BL/6 Mice

Periodontitis is a chronic inflammatory disease that leads to the destruction of the supporting structures of teeth, primarily due to bacterial infection and immune response. The ligature-induced periodontitis (LIP) model is commonly used to replicate this condition in experimental settings, facilitating the study of inflammation and bone loss as well as testing therapeutic strategies. In this study, we aimed to establish an experimental ligature-induced periodontitis model in mice and evaluate the extent of alveolar bone loss over a 10-day period and discuss advantages and limitations. Eight 10-week-old pathogen-free C57BL/6 male mice were divided into two groups: an experimental group (n=4) with ligature placement and a control group (n=4) without ligature. Under sedation, a silk suture (6-0) ligature was placed around the maxillary second molar (M2) of the experimental group to induce bacterial accumulation, gingival inflammation, and bone resorption over 10 days. Bone resorption was confirmed through microscopic analysis. The experimental group demonstrated a significant increase in alveolar bone loss compared to the control group. The average distance from the cemento-enamel junction (CEJ) to the alveolar bone crest (ABC) was greater in the ligature group, while no bone loss was observed in the control group (P < 0.05). These results demonstrated a clear correlation between the experimental conditions and outcomes, highlighting the murine periodontitis model as a valuable tool for studying inflammatory conditions. These findings offer insights into bone loss mechanisms and may aid in developing targeted therapies for bone resorption in periodontitis.