In 1978, various microfilled systems were introduced into the European market. These composite resins were appealing, in that they were capable of having an extremely smooth surface when finished. These microfilled composite resins also showed a better clinical colour stability and higher resistance to wear than conventional composites, which favoured their tooth tissue-like appearance as well as clinical effectiveness. However, further research showed a progressive weakness in the material over time, leading to micro-cracks and step-like material loss around the composite margin. In 1981, microfilled composites were improved remarkably with regard to marginal retention and adaptation. It was decided, after further research, that this type of composite could be used for most restorations provided the acid etch technique was used and a bonding agent was applied.