What characterizes Internal Tooth Resorption?

Internal tooth resorption is characterized primarily by pulp overgrowth. This condition occurs when the dental pulp, which is the innermost part of the tooth containing nerves and blood vessels, begins to resorb the surrounding tooth structure. In this process, the body's own immune response can inadvertently attack the tooth from the inside, leading to an increase in pulp tissue and potential damage to the tooth's structure if left untreated.

While other options describe various dental issues, they do not accurately depict internal tooth resorption. The decay of the enamel layer refers to external carious lesions, which is not related to the internal processes occurring in resorption. Loss of tooth structure can happen with many dental diseases, but it is more general and does not highlight the unique characteristic of pulp involvement found in internal resorption. Similarly, the development of cavities in dentin is typically associated with external caries and decay, which also does not encompass the internal changes that occur during internal resorption. Thus, the defining feature of internal tooth resorption is indeed the overgrowth or alteration of the pulp, leading to the specific resorptive changes within the tooth.