A child lost the primary mandibular second molar before the permanent first molar has erupted. Which space maintainer is indicated?

Correct answer: D. Distal shoe space maintainer

• A. ❌ Lower lingual holding arch is used after permanent first molars have erupted to prevent mesial drift.
• B. ❌ Nance holding arch is a maxillary appliance, not for mandibular second molar loss.
• C. ❌ Band and loop is used when adjacent permanent teeth have already erupted.
• D. ✅ Correct. The distal shoe is specifically designed for early loss of primary second molar BEFORE the permanent first molar has erupted. A metal extension goes subgingivally to guide the permanent first molar into correct position.

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