This document discusses different types of pulpitis, inflammation of the dental pulp. It defines reversible pulpitis as a mild inflammation where the pulp can return to normal after stimulus removal. Irreversible pulpitis is a persistent inflammation where pain lasts for minutes to hours after stimulus removal. Pulp necrosis occurs when the pulp has died, either partially or totally. The document provides details on causes, symptoms, diagnosis, and treatment for each type of pulpitis.