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Functional Appliance Growth Timing — NDEB AFK MCQ

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ModerateOrthodonticsFunctional Appliance Growth TimingNDEB AFK

Functional appliance therapy (e.g., twin block) is most effective during which growth period?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: D — During the pubertal growth spurt (CVM stage 2-3)

Functional appliances (twin block, Herbst, Fränkel, bionator) achieve their maximum skeletal effect during the pubertal growth spurt (CVM stages 2-3, approximately 11-14 years in males, 10-13 years in females). During this period, condylar growth is at its peak, and the mandible can be stimulated to grow forward (advancement of approximately 2-3 mm additional mandibular length compared to untreated controls). Treatment before or after the growth spurt produces primarily dental effects (proclination of lower incisors, retroclination of upper incisors) with minimal skeletal modification.

Reference: Proffit – Contemporary Orthodontics, 6th ed., 2019