The public opinion on restorations has changed significantly; patients are now aware that aesthetic alternatives are also possible, and metal restorations are unnecessary. Modern dental amalgam comprises mercury, silver, tin, and copper, an alloy with a dull metallic color that does not match well aesthetically with the natural teeth. The development of resin composite benefits aesthetics, being modified to match the color and clarity of the patient's teeth]. The common opinion on restorations was focused on their longevity in the past. Moreover, one reason why amalgam remains a popular form of treatment is that it is much easier to place than a resin composite. However, while the dentist is still concerned about longevity and technique sensitivity, patients are provided aesthetics.
Resins composite restorations
Amalgam has consistently been shown to have a lower wear rate than resin composite in the past. However, recent technology in current resin composite has improved, and current resin composite technologies have wear, very similar to those of human enamel structure. Resin composite restorations are more aesthetically pleasing and offer clinical advantages over amalgam.
Despite the aesthetic improvements of resin composite relative to amalgam, one of the disadvantages of resin composite is shrinkage from polymerization. The factors influencing polymerization shrinkage include volumetric shrinkage and viscoelastic behavior. Volumetric shrinkage refers to the reduced distance between two categories of atoms when a covalent bond is formed between monomers and the reduction in free volume . Three factors contributing to the magnitude of polymerization shrinkage stress include the resin composite's composition, conversion of the resin matrix, and its filler volume fraction.
Given that amalgam has a longer lifespan relative to resin composite, the patients probably care more for aesthetics than the length of time their restorative materials last. In addition to these benefits, resin composite has also been shown to offer clinical advantages such as enamel bonding, and it helps to strengthen the tooth.