Signs and symptoms of pulpitis - Increased sensitivity to hot and cold stimuli - Prolonged throbbing pain - Reversible pulpitis: intermittent, brief discomfort with no lingering pain - Positive pulp vitality tests - Irreversible pulpitis: constant severe pain with sharp and lingering thermal pain

Causes of pulpitis - Bacterial infection from dental caries - Mechanical trauma or physical damage to the tooth - Inflammation from repetitive trauma or periodontitis - Opportunistic infection of the pulp by oral microorganisms - Penetrating decay leading to exposure of the pulp chamber

Responses to pulpitis - Inflammatory response in the pulp - Innate immune response using receptors to recognize microbial patterns - Odontoblasts attracting immature dendritic cells - Accumulation of pulpal dendritic cells in response to infection - Transition to adaptive immune response with antigen recognition and antibody production

Inflammatory mediators in pulpitis - Cytokines, including IL-8, increased in symptomatic and asymptomatic irreversible pulpitis - Interaction of cytokines in the pulp - B cells and T cells involved in lymphocyte response - Macrophages as class II antigen-presenting cells - Activation of macrophages by priming and activating stimuli

Role of macrophages in pulpitis - Macrophages as professional phagocytes in innate immune responses - Activation of macrophages by T-helper cells and chemical mediators - Elimination of pathogens in both innate and adaptive immune responses - Importance in tissue homeostasis and repair after inflammation - Increased number of macrophages with progression of caries