Purpose: To evaluate the four-year performance of a highly filled resin composite in Class II and Class I cavities. Materials and Methods: Each of 63 participants received at least one pair of restorations of the same size: one resin composite (Tetric Ceram) and one calcium aluminate cement. Seventy-one pairs were placed. The restorations were evaluated clinically according to slightly modified USPHS criteria at baseline, after 6 months, 1, 2, 3, and 4 years. At 3 years, the calcium aluminate cement material showed an inacceptable clinical cumulative failure frequency of 57% and its evaluation was discontinued. Results: Postoperative sensitivity was reported for 5 restorations (2 resin composite, 3 calcium aluminate cement). At 4 years, a cumulative failure frequency of 7.5% was observed for the resin composite material. Reasons for failure were partial material fracture (2), cusp fracture (2) and endodontic treatment (1). Conclusion: An annual failure rate of 1.9% for the resin composite material provided a good clinical performance during the 4-year period, which fulfills the ADA criteria for posterior resin composite materials. Schlagwörter: dental restorations, cement, ceramic, clinical, composite resin