IADR Abstract Archives
Effect of Different Surface Preparations on Aged Resin-Composite Repairs' Bond-Strength
Objectives: This study investigated the effect of different surface treatments on the repair shear bond strength (SBS) of aged resin-based composites (RBCs).
Methods: Forty-eight surface-polished cylindrical composite samples (2x8mm) were fabricated using a custom-made cylindrical metal mold made of Filtek Ultimate (shade A2, 3M ESPE). The samples were stored in distilled water at 37 °C for one year. The samples were divided into four groups according to surface treatment: Orthophosphoric acid (O), air abrasion (27µ aluminum oxide particles) (A), fine-grained diamond abrasive (D) and Katana Cleaner (Kuraray Noritake) (K). After treatment, Clearfil Ceramic Primer Plus (Kuraray Noritake) and Clearfil Universal Bond Quick (Kuraray Noritake) were applied according to the manufacturer's instructions. The specimens were placed on an Ultradent template (Ultradent Products Inc.) to build up the RBC (Clearfil Performance Pro, shade A2, Kuraray Noritake). The samples were then stored in distilled water at 37 °C for 24 hours and subjected to SBS testing.
The samples were loaded with a shear force at a crosshead speed of 0.5 mm/min. The loads were then converted to MPa. The fractured surfaces were examined at 50x magnification to assess the failure modes. They were classified as adhesive, cohesive or mixed failure modes. The data were analyzed using Kruskal-Wallis and the post-hoc Bonferroni test (p<0.05).
Results: The highest value of SBS was obtained in group A (21.14±9.52 MPa), followed by group D (15.50 ±5.61 MPa). The SBS values of group A were significantly higher than those of the other groups (p<0.05). Group K showed the lowest SBS values (12.36±6.46 MPa) and exhibited the greatest variation in bond strength measurements. The failure modes of group A were predominantly cohesive fractures of the composite surfaces.
Conclusions: The results of this study indicate that air blasting old RBCs surfaces increases the repair bond strength of new RBCs.
Methods: Forty-eight surface-polished cylindrical composite samples (2x8mm) were fabricated using a custom-made cylindrical metal mold made of Filtek Ultimate (shade A2, 3M ESPE). The samples were stored in distilled water at 37 °C for one year. The samples were divided into four groups according to surface treatment: Orthophosphoric acid (O), air abrasion (27µ aluminum oxide particles) (A), fine-grained diamond abrasive (D) and Katana Cleaner (Kuraray Noritake) (K). After treatment, Clearfil Ceramic Primer Plus (Kuraray Noritake) and Clearfil Universal Bond Quick (Kuraray Noritake) were applied according to the manufacturer's instructions. The specimens were placed on an Ultradent template (Ultradent Products Inc.) to build up the RBC (Clearfil Performance Pro, shade A2, Kuraray Noritake). The samples were then stored in distilled water at 37 °C for 24 hours and subjected to SBS testing.
The samples were loaded with a shear force at a crosshead speed of 0.5 mm/min. The loads were then converted to MPa. The fractured surfaces were examined at 50x magnification to assess the failure modes. They were classified as adhesive, cohesive or mixed failure modes. The data were analyzed using Kruskal-Wallis and the post-hoc Bonferroni test (p<0.05).
Results: The highest value of SBS was obtained in group A (21.14±9.52 MPa), followed by group D (15.50 ±5.61 MPa). The SBS values of group A were significantly higher than those of the other groups (p<0.05). Group K showed the lowest SBS values (12.36±6.46 MPa) and exhibited the greatest variation in bond strength measurements. The failure modes of group A were predominantly cohesive fractures of the composite surfaces.
Conclusions: The results of this study indicate that air blasting old RBCs surfaces increases the repair bond strength of new RBCs.