However, there is low-quality evidence to suggest that resin composites lead to higher failure rates and risk of secondary caries than amalgam restorations. Several reviews have been made by using database in the Cochrane Library where randomized controlled trials of few studies comparing dental resin composite with dental amalgams in permanent posterior teeth were compared. This review supports the fact that amalgam restorations are particularly useful and successful in parts of the world where amalgam is still the material of choice to restore posterior teeth with proximal caries. Though, there is insufficient evidence to support or refute any adverse effects amalgam may have on patients, new research is unlikely to change opinion on its safety and due to the decision for a global phase-down of amalgam (Minamata Convention on Mercury) general opinion on its safety is unlikely to change.