IL6 and retinopathy of prematurity: The salivary levels of interleukin (IL)-6, IL-8, vascular endothelial growth factor (VEGF), and tumor necrosis factor (TNF)-α on D1 and D7 were significantly higher in the Moderate to Severe ROP group compared to the None to Mild ROP group (p = 0.005, 0.004, 0.026, 0.018, 0.001, 0.007, 0.025, and 0.002, respectively).