effect of type of adhesive system on bond strength of repaired bulkfill composite

Abstract

Background and Aim: In most cases, the repair of existing oral restoration is preferred to change the whole restoration. Recently, the usage of bulk-fill composites in posterior restorations is on the progress. Consequently, number of patients with old restorations that be needed to be repaired are increased. In addition the eighth generation and universal generation of dental bondings are recently introduced, and there aren’t any studies about bulk-fill composites repairing with new adhesive systems up to now. Accordingly, we designed a study in order to evaluate the effect of elective bonding system on the result of bulk-fill composite repairs, seems to be essential. Materials and methods: Fifty four samples of two types of bulk-fill composites (X-tra fil dental Bulk Fill composite (VOCO/Germany)) and (Tetric EvoCeram Bulk Fill composite (Ivoclar Vivadent)) and three types of adhesive bonding: Scotchbond universal adhesive (3M ESPE), G-Premio Bond (GC) and ClearFil SE Bond (Kuraray) were prepared and used. The composite samples were placed in the mold and be flatted by glass slab and then, were light cured. The samples were stored in distilled water. Then, they were thermocycled. The samples were divided into 6 groups (n=9) and each composite was repaired with the same composite and deferent adhesive systems. Prepared samples were stored in distilled water once more. Then, the shear bond strength test was established using the universal test machine with loading speed of 0.5 mm/min. The statistical data analysis was done with SPSS 17 software. (p<0.05) Results and conclusion: The results of samples Independent T Test showed that there is no statistical significant difference between mean of bond strength of two types of BulkFill composites (p-value>0.05). In addition, the results of one way ANOVA test showed that there is no statistical significant difference between mean of bond strength of three types of adhesive systems (p-value>0.05). In conclusion, the type of adhesive doesn’t have significant effect on the bond strength of repaired bulk fill composites. Also, the type of bulk-fill composite doesn’t have significant effect on the bond strength.