The article describes studies aimed at investigating factors that can influence composite restoration survival in posterior teeth, focusing on the main reasons for failure of direct restorations - fracture and secondary-caries. Since direct composite resin restaurations seem to be more prone to secondary caries when compared to amalgam, one study was performed to evaluate the influence of materials on secondary caries lesion formation in situ. Also, in most clinical studies evaluating restoration survival, there is a tendency to focus on materials factors. Two retrospective clinical investigations, a meta-analysis with primary data of clinical studies and a systematic review were performed to assess the influence of patient-, materials-, and tooth-related variables in posterior composite restoration survival. Composite resins were not related with higher mineral loss when compared to amalgam. Tooth type, number of restored surfaces and patient-related factors like a high caries risk and occlusal wear were consistently found to influence composite resin restoration survival in posterior teeth, whereas materials factors were not consistently implicated with the survivalrate.