Table 1.
Surface treatments and tensile bond strength (TBS) results (MPa).
| Group | Surface Treatment | TBS (SD) |
|---|---|---|
| Group 1 Negative Reference | Red code diamond bur (grain size 27–76 µm) | 4.86 a (±1.06) |
| Group 2 | Etching with 35% phosphoric acid (Scotchbond Etchant, 3M ESPE, St. Paul, MN, USA) for 15 s | 6.75 b (±1.40) |
| Group 3 | Blue code diamond bur (grain size 64–126 µm) | 7.15 b (±1.85) |
| Group 4 | Sandblasting (CoJet-System, 3M ESPE, Seefeld, Germany) with 35 µm Al2O3 particles (2.8 bar for 4 s at 20 mm distance) | 7.9 b (±1.64) |
| Group 5 | Silane application for 60 s | 6.62 b (±1.59) |
| Group 6 | Sandblasting with 30 µm CoJet Sand (2.8 bar for 4 s at 20 mm distance) and subsequent silane application for 60 s | 7.75 b (±1.87) |
| Group 7 | Application of Syntac Primer for 15 s and careful drying with compressed air | 9.82 c,d (±1.76) |
| Group 8 | Application of Syntac Adhesive for 10 s and careful drying with compressed air | 10.03 c,d (±1.51) |
| Group 9 | Application of Heliobond for 60 s, careful drying with compressed air and light polymerization for 40 s | 9.35 c (±2.05) |
| Group 10 | Application of Syntac Primer + Adhesive and subsequent application of Heliobond | 9.67 c,d (±1.88) |
| Group 11 | Etching with 35% phosphoric acid followed by Syntac Primer + Adhesive and Heliobond | 11.33 d (±2.03) |
| Positive reference | No surface treatment, no aging after repair | 10.07 c,d (±1.54) |
| Positive reference | No surface treatment. After repair, aged in distilled water for 30 days | 10.54 c,d (±2.04) |
Means followed by the same superscript letters are not statistically different (at p < 0.05).