Which compound commonly serves as the photoinitiator in many light-cured dental composites?

Which compound commonly serves as the photoinitiator in many light-cured dental composites?

• A. Camphorquinone
• B. Tertiary amine
• C. HEMA
• D. Bis-GMA

Answer: (A)

In light-cured dental composites, polymerization begins when a photoinitiator absorbs blue light and generates free radicals to start the methacrylate polymer network. Camphorquinone is the most commonly used photoinitiator because it strongly absorbs blue light around 468 nm and, with a tertiary amine co-initiator, efficiently forms the radicals needed to kick off polymerization. This pairing provides reliable curing with typical dental blue-light sources and good esthetic properties. The other substances listed are not initiators: HEMA and Bis-GMA are resin monomers that form the matrix, while a tertiary amine acts as a co-initiator rather than the primary initiator itself.

In light-cured dental composites, polymerization begins when a photoinitiator absorbs blue light and generates free radicals to start the methacrylate polymer network. Camphorquinone is the most commonly used photoinitiator because it strongly absorbs blue light around 468 nm and, with a tertiary amine co-initiator, efficiently forms the radicals needed to kick off polymerization. This pairing provides reliable curing with typical dental blue-light sources and good esthetic properties. The other substances listed are not initiators: HEMA and Bis-GMA are resin monomers that form the matrix, while a tertiary amine acts as a co-initiator rather than the primary initiator itself.