PTH and periodontal disorder: Among the main mediators against periodontal disease, various factors can be counted, e.g., hormones (parathyroid hormone, vitamin D3, and proteins related to parathyroid hormones), TNF-α, IL-1, -6, -11, and -17, growth factors (bone-2 morphogenetic protein, BMP) and other mediators such as prostaglandin E2, CD40 ligand activating T (CD40L), and glucocorticoid cells [101].