visiblelightcured

Visible light cured refers to materials that harden or polymerize when exposed to visible light, typically in the blue-green range of about 400 to 500 nanometers. These materials contain photoinitiators that absorb light and generate reactive species, such as free radicals, to start polymerization of resin monomers.

The mechanism involves a photoinitiator absorbing light and initiating a chain reaction that converts liquid resin into a crosslinked solid. Camphorquinone is a common initiator in dental resins, often paired with a co-initiator. More recent initiators, such as TPO or Ivocerin, respond to different wavelengths and can improve curing performance in certain formulations.

Visible light curing has broad applications, especially in dentistry, where blue-light activated resin composites, bonding agents, sealants, and luting cements are common. It is also used in coatings, adhesives, and printing inks to achieve rapid, on-demand setting without heat.

Advantages include rapid curing, controllable set times, absence of thermal damage, and the ability to cure specific layers or sections. Limitations involve the need for adequate light exposure and material translucency; opacity, thickness of the layer, and light scattering can hinder depth of cure. Incomplete polymerization can affect mechanical properties and color stability. Some formulations may impart color to the material, influencing aesthetic outcomes.

Safety considerations include protecting eyes and skin from intense blue light. Proper curing lights (often LED) and recommended exposure times are important to achieve optimal polymerization and material performance.