“…A wide range of immune and non-immune cells in the pulp produce and secrete chemokines and cytokines, such as chemokine (C-C Motif) Ligand 2 (CCL2), CXCL1, CXCL2, CXCL8 (IL-8), CXCL10 IL-1α, IL-1β, IL-4, IL-6, IL-10, transforming growth factor (TGF)-1β, and tumor necrosis factor (TNF)-α, which are small glycoproteins (10 to 15 kD) that act as paracrine and autocrine molecular key agents because they regulate the recruitment, extravasation, activation, and differentiation of the immune cells of the pulp tissue [21][22][23]. During these inflammatory events, the nerve fibers of the peripheral nervous system are stimulated, which secrete many molecules, such as classical neurotransmitters (acetylcholine, glutamate, catecholamines), neuropeptides (substance P, calcitonin gene-related peptide, neuropeptide Y, neurokinin A), and excitatory amino acids, which contribute to the induction, sensitization, and maintenance of dental pain [24].…”