[Effect of experimentally created disordered occlusion on the expression of IL-1β, IL-6 and TNF-α in condylar cartilage of rats].

PURPOSE: To investigate the effect of the experimentally created malocclusion (ECDO) on the expression of IL-1β, IL-6 and TNF-α in mandibular condylar cartilage of Sprague Dawley (SD) rats.

METHODS: In the experimental group, the malocclusion was created by moving the first and third molars 0.8 mm away. HE and immunohistochemical staining were performed on the mandibular condyle at the end of the 8th or 12th week. Gene expression was analyzed by real-time PCR. The data was processed using SPSS12.0 software package.

RESULTS: Degenerative changes were found in the experimental group, the level of IL-1β was not significantly different among the groups (P>0.05), while the expression of IL-6 in 8-week ECDO subgroup was significantly higher than that in 8-week control subgroup (P=0.009), and the expression of TNF-α in 8-week ECDO subgroup was significantly higher than that in 8-week control subgroup (P=0.001) and 12-week ECDO subgroup (P=0.004).

CONCLUSIONS: At the early period, IL-6 and TNF-α, but not IL-1β, play an important role in the degenerative remodeling procedure in rat condylar cartilage induced by ECDO.