Which teeth undergo physiologic root resorption?

• A. All teeth equally.
• B. Deciduous teeth.
• C. Permanent incisors.
• D. Permanent molars.

Answer: (B)

Physiologic root resorption is the natural process by which the roots of deciduous teeth are dissolved to make way for the eruption of permanent successors. Odontoclasts chip away at the cementum and dentin of the deciduous roots, usually starting at the apex and moving coronally. As the roots shorten, the deciduous tooth loosens and is shed, while the crown remains in the mouth until shedding completes. This resorption is driven by signals from the erupting permanent tooth and surrounding tissues, and it stops once the permanent tooth has erupted and taken its place. Permanent teeth don’t shed through this normal resorption process; they can undergo root resorption only due to pathology or other factors, not as a routine developmental step. So the deciduous teeth are the ones that undergo physiologic root resorption to be replaced by their permanent successors.