How can you differentiate physiologic root resorption associated with eruption from pathologic external resorption on radiographs?

Study for the Pediatric Dentistry II Exam. Utilize flashcards and multiple choice questions with hints and explanations. Prepare thoroughly for your exam!

The key idea is pattern and timing. Physiologic root resorption related to eruption is a normal, predictable process that accompanies the eruption of the permanent successor. On radiographs it tends to be symmetric and progress at a rate that matches the eruption schedule, with smooth, uniform margins along the roots that are being resorbed.

Pathologic external resorption, on the other hand, is abnormal. It usually presents as irregular, ragged resorption with irregular margins, can occur more rapidly, and is often localized to a tooth or area rather than showing the orderly, symmetric pattern seen with eruption. It may also be accompanied by symptoms or signs of underlying pathology, such as infection, trauma, or pressure from an adjacent erupting tooth or lesion.

So, when radiographs show resorption that is symmetric and occurring in step with expected eruption timing, that aligns with physiologic eruption-related resorption. Irregular, accelerated, and potentially symptomatic resorption points toward a pathologic process.