Polymerization of Composite Resins: Dental Chemistry

A composite is defined as the combination of two or more chemically different materials that have properties better than when the compounds act alone. Resin composites, which are used in dentistry, are compounds composed of three separate agents that act together to form a rigid polymer. The three agents that act together to form the polymer include, an organic resin matrix, inorganic filler, and a coupling agent. The most important agent, the organic resin matrix, …

…very quick. This in fact happens so quickly that some polymer molecules have unreacted carbon double bonds at the terminal ends. Using a degree of conversion, they are able to determine the amount of material that reacted within the polymer matrix. This degree of conversion is directly affected by the amount of time exposed to the curing light. The longer exposed to the duration of exposure, the greater conversion rates will be within the matrix.