Amalgam (dentistry) on Mercury) general opinion on its safety is unlikely to change. These are some of the reasons why amalgam has remained a superior restorative material over resin-base composites. The New England Children's Amalgam Trial (NECAT), a randomized controlled trial, yielded results "consistent with previous reports suggesting that the longevity of amalgam is higher than that of resin-based compomer in primary teeth and composites in permanent teeth. Compomers were seven times as likely to require replacement and composites were seven times as likely to require repair. There are circumstances in which composite serves better than amalgam. For example, when a more
Amalgam (dentistry) or longer to reach a reasonably high value. At the time when the patient is dismissed from the surgery, typically some 15–20 minutes after placing the filling, the amalgam is relatively weak. Therefore, dentists need to instruct patients not to apply undue stress to their freshly placed amalgam fillings. In addition, amalgam restorations are brittle and susceptible to corrosion. The alloys are broadly classified as low-copper (5% or less copper) and high-copper alloys (13% to 30% copper). The solid particles of the alloy are either spherical or irregularly shaped microspheres of various sizes or a combination of the two. The