AbstractStatement of ProblemComposite resins are still outperformed by amalgams in the clinical practice with secondary caries and fractures being their most common failures. A material that suffers less polymerization shrinkage might improve the clinical performance of composite resins.PurposeTo evaluate the clinical performance of a low‐shrink silorane‐based composite resin (Filtek LS Low Shrink Posterior Restorative, 3M ESPE, St. Paul, MN, USA) in comparison with a methacrylate‐based composite resin (Tetric EvoCeram, Ivoclar Vivadent, Schaan, Principality of Liechtenstein) over time.Materials and MethodsCandidates in need of Class II composite resin restorations participated in this randomized controlled clinical trial. Those were 25 female and six male subjects with average age of 44.3 ± 12.7 years. Participants received 82 restorations, being 54 in premolars and 28 in molars. Procedures, which included the restoration of primary caries lesions or replacement of failing restorations, were done using modified preparations with no bevels or additional retention. Restorations were placed using Filtek LS (and dedicated self‐etch adhesive) or Tetric EvoCeram (with AdheSE, Ivoclar Vivadent), following manufacturers' instructions. Incremental placement technique was applied and the restorations were immediately finished. Follow‐up evaluations occurred at six, 12, 24, and 36 months and were done using the Fédération Dentaire Internationale criteria. Statistical analysis was performed using generalized estimating equations.ResultsThe recall rate at 36 months was 89%. All interaction terms were not significant.ConclusionsFiltek LS performs as well as Tetric EvoCeram performs in the clinical setting at 36 months.Clinical SignificanceThe silorane‐based composite resin Filtek LS and the conventional methacrylate‐based composite resin Tetric EvoCeram performed similarly well in posterior restorations over at least 36 months of clinical service.