Clinical evaluation of posterior composite restorations: 6-year results

Purpose To evaluate the wear resistance of resin restorations (Z100; Tetric ; Charisma) in posterior teeth (Class I and II) after 6 years. Material and Methods: One operator placed 103 restorations in 13 patients. Each patient had at least three restorations with three different resin-based composite s. All restorations were made using rubber dam isolation and the cavity des ign was restricted to the elimination of carious tissue. Deeper cavities we re covered with calcium hydroxide and/or glass ionomer cement and in shallo w and medium cavities, only an adhesive system was used. Each composite was placed according to the manufacturer's instructions. In Class II cavities the resin placement followed the Krejci et al or Opdam et al technique, acc ording to the cavity size. One week later, the restorations were fin-ished/ polished and stone:dies were immediately built from the impressions. Eleven patients attended the 6-year recall, and 90 restorations were evaluated ba sed on new stone dies. The 6-year stone dies were compared with-the baselin e ones by two examiners. The evaluation was based on the modified Mahler et al. criteria and Busato et al, using six different scores. The scores were statistically analyzed. Results: A total of 87% of the restorations were a nalyzed after 6 years. Only 15% (6 for Tetric. and 7 for Charisma) of the 9 0 evaluated restorations had been already replaced. No statistical differen ce was found in the wear rate of the composites used in this study. None of the patients complained of any symptom after the placement of the composit e (baseline data) nor after 6 years.