Abstract: Objective: To analyze the expression of interleukin-1β and matrix metalloproteinase-2 in the periodontal tissues of rat during root resorption. Methods: Thirty Wistar rats were randomly divided into three groups, each with ten rats. Group A was the blank control group, and no treatment was done. Group B was applied 40g force on the right upper incisor and the first molar, and group C was applied 100g force at the same position. The degree of root absorption of the teeth was observed by histologically. Before and after 1, 7, 14, 21, and 28 days, interleukin-1β and matrix metalloproteinase-2 of gingival crevicular fluid were detected by enzyme-linked immunoassay. Results: HE staining showed no obvious root absorption in group A, with dense periodontal membrane fibers and regular arrangement and bone resorption in group B, and the osteoblasts were cubic arranged at the margin of alveolar bone. In group C, periodontal fibers were disordered, and the root was absorbed at the bifurcation point and absorbed to the dentin layer. Before applying the force, there was no statistically significant difference in expression of interleukin-1β and matrix metalloproteinase-2 among three groups (P>0.05). After 1 day of force application, interleukin-1β and matrix metalloproteinase-2 levels in group A were (108.7±7.25)mg/L and(658.3±28.9)μg/L, (165.2±12.4)mg/L, and (702.3±30.4)μg/L in group B,(225.7±16.4)mg/L and(845.7±46.4)μg/L in group C. The differences were statistically significant (P<0.05), and group C was significantly higher than group B and group A, reaching peak on the 7th day. Conclusion: The levels of nterleukin-1β and matrix metalloproteinase-2 are involved in root resorption, and monitoring them can provide new ideas for root resorption diagnosis and prevention.

Key words: Root absorption, Animal models Interleukin-1β , Matrix metalloproteinase-2