Physiologic root resorption is best described as which of the following?

• A. Resorption of permanent tooth roots during aging.
• B. Cementum deposition on erupting teeth.
• C. Normal resorption of deciduous tooth roots to allow eruption of permanent successors.
• D. Resorption of enamel during eruption.

Answer: (C)

Physiologic root resorption is the normal resorption of the roots of primary teeth to allow eruption of the permanent successors. Odontoclasts resorb cementum and dentin of the deciduous roots as the developing permanent tooth moves into position, and this resorption progresses until the primary tooth exfoliates and the permanent tooth is fully erupted. Enamel is not resorbed during eruption, so resorption of enamel isn’t involved. Cementum deposition on erupting teeth refers to cementogenesis, not resorption. And resorption of permanent tooth roots with aging isn’t a normal physiologic process; when root loss occurs in adults it’s typically pathologic rather than a normal part of aging.