Correlations of the expression of fibroblast growth factor-2, vascular endothelial growth factor, and their receptors with angiogenesis in synovial tissues from patients with internal derangement of the temporomandibular joint.

Synovitis in internal derangement of the temporomandibular joint (TMJ) is accompanied by the growth of new blood vessels. Fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor (VEGF) are well-characterized angiogenic factors. The objective of this study was to elucidate the correlation between the expression of FGF-2, VEGF, and their receptors-FGF receptor-1 (FGFR-1) and VEGF receptor-1 (Flt-1)-with microvessel density in synovial tissues of the TMJ. Using an immunohistochemical technique, we examined 47 joints (45 patients) with internal derangement. Individual microvessel density was evaluated by means of the CD34 antibody, a specific endothelial marker. The correlation between the percentage of immuno-positive cells and microvessel density was evaluated. In multiple logistic regression analysis, the correlation between the percentage of Flt-1-positive cells and microvessel density was significant [p = 0.005, odds ratio = 1.071, 95% confidence interval = 1.021-1.124]. These results suggest that the expression of the VEGF/Flt-1 system is involved in angiogenesis in inflamed synovial tissue in the TMJ.