Which maxillary tooth tends to shed first, reflecting the exception to the general rule?

• A. Central incisor
• B. First molar
• C. Second molar
• D. Canine

Answer: (C)

The idea being tested is the pattern of shedding (exfoliation) of deciduous teeth and how eruption of the permanent teeth can change which primary tooth resorbs first.

In most cases, shedding begins with the mandibular central incisor, reflecting the general trend that anterior teeth in the mandible are lost earlier. But in the maxillary arch there’s an exception: the deciduous second molar tends to be the first maxillary tooth to shed. This happens because the eruption of the permanent first molar behind it accelerates resorption of the deciduous second molar’s roots, so that tooth is resorbed and shed earlier than the others. That’s why the upper second primary molar is often the first maxillary tooth to exfoliate.

The other maxillary teeth shed later because their roots resorb in the normal sequence as the permanent successors erupt.