‘Let there be Light,’ and there was Light, but was it Enough? A Review of Modern Dental Light Curing

Over recent years, a plethora of new light-curable, resin-containing restorative materials and dental light-curing devices or units (LCU) has been brought to the market. It is not always clear whether the ‘new’ technology will improve practice and restoration longevity, or whether it is merely an incremental step, or, at worst, inferior to the products that have used before. Furthermore, the profit margins of dental resin composite material and light manufacturers are relatively small given the huge investment costs of research and development for these technologies. Slick marketing by manufacturers within a finite window of opportunity is often key to maximize small profit margins before the next ‘new’ version is designed and marketed. This often results in materials and related technologies that become quickly defunct before there is a full understanding of how they might perform clinically in the long term, which presents a challenge for the dental practitioner in terms of material and device selection. For each new product, the dental team must ensure that they are using the material as intended by the manufacturer and, in the case of light-curable dental materials, it is imperative that the clinician fully understands the process of dental light curing. This review summarizes key aspects that influence optimal photopolymerization, and how both a basic knowledge of chemistry and the properties of the light-curing device are essential to achieve optimal clinical performance of the material.