Composite Material: A material is considered a composite when it is made of two or more constituent materials with significantly different physical or chemical properties, that when combined produce a material with characteristics different from the individual components. In dentistry the constituents are usually a resin matrix and small filler particles.
Flexural Strength: Also called bend strength or fracture strength, this measurement of how well a material resists breaking under a load is often measured in megapascals.
Nanoscale: The term used to refer to structures with a length smaller than 100 nanometers. A nanometer is one billionth of a meter.
Photoinitiator: A chemical compound added to dental composites to promote polymerization when exposed to the proper light wavelengths.
Shrinkage: The percentage the volume of dental composite material reduces in size following the curing process.