What is exposed when a fractured crown is painful?

When a fractured crown is painful, it indicates that the pulp cavity is likely exposed. The pulp cavity contains nerves and blood vessels, which are sensitive to trauma, infection, and other stimuli. When the crown of a tooth is fractured, if the fracture extends deep enough, it can breach the protective outer layers of the tooth—specifically the enamel and dentin—allowing the sensitive pulp to become exposed. This exposure can lead to pain, as the nerves within the pulp react to environmental changes and potential irritants, such as temperature changes or microbial invasion.

The health of the pulp is crucial because it not only provides sensation but also nourishment to the tooth. If not treated promptly, an exposed pulp can lead to more severe conditions, such as pulpitis or even tooth loss. Therefore, identifying exposure of the pulp cavity in the context of dental health is essential for proper diagnosis and treatment planning.