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LED Curing Light — NDEB AFK MCQ

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EasyDental MaterialsLED Curing LightNDEB AFK

Which type of light source is most commonly used in modern dental curing lights for polymerising composite resin?

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

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Correct answer: B — LED (light-emitting diode)

LED (light-emitting diode) curing lights have largely replaced halogen (QTH) lights as the standard in dental practice. LED units emit blue light at a peak wavelength of approximately 450-470 nm (matching the absorption spectrum of camphorquinone, the most common photoinitiator in composites). Advantages over halogen include: no heat filter needed, no bulb degradation over time, longer lifespan (>10,000 hours vs ~40-100 hours for halogen), cooler operation, cordless portability, and instant-on operation.

Reference: Anusavice – Phillips' Science of Dental Materials, 13th ed., 2022