Purpose: This prospective clinical trial evaluated the clinical acceptability of a new material, ceromer, used for inlay and onlay restorations in single- or multisurface cavities of posterior teeth. Materials and Methods: Forty-three Targis inlay and onlay restorations were placed in 25 patients and evaluated using the United States Public Health Service criteria. The laboratory work was conducted by three dental technicians according to the manufacturers recommendations. Twenty-five restorations were luted with Syntac bonding system and Variolink II, and 18 were luted with Scotchbond Multi Purpose and Opal Luting Composite. The recalls were done at 6, 12, and 18 months. Restorations were evaluated for six parameters and scored as ideal (A), clinically acceptable (B), or clinically unacceptable (C). Results: Indirect restorations received, after 18 months, scores of A at the following rates: color match 77%; marginal discoloration 93%; secondary caries 100%; anatomic form 93%; and marginal integrity 95%. For these parameters, statistical analysis indicated no significant differences at baseline and after 18 months. Postoperative hypersensitivity was reported by seven patients at baseline, but it decreased and there was no hypersensitivity at 12- and 18-month follow-ups. Conclusion: Over an 18-month period the Targis restorative system yielded good clinical service.