Mandibular lateral shift induces the increased expression of TGF-β, VEGF, and Col-II in the condyle of rat temporomandibular joints

Abstract

The present study evaluates histologic changes to and expression of angiogenic factors in rats with mandibular functional shift (MFS). After 1, 2, and 4 weeks of MFS, rats in the experimental and control groups were killed. Histologic micrographs of the ipsilateral condyle cartilage were obtained. The localization and expression of vascular endothelial growth factor (VEGF), transforming growth factor beta (TGF-β), and type-II collagen (Col-II) in temporomandibular joints (TMJs) were evaluated through immunohistochemical staining. The results showed that structural changes in the condyle cartilage could be observed 2 weeks after MFS. TGF-β expression reached its peak 2 weeks post-MFS, whereas VEGF and Col-II reached their peaks 4 weeks posttreatment. Compressive forces applied to the TMJ could enhance the expressions of VEGF, TGF-β, and Col-II, and activate angiogenesis. The proteins appear to play important roles in the remodeling of the TMJ.