Objectives: Today self-adhesive resin cements are used universally to cement indirect restorations of all types. Apart from adhesion to tooth, adhesion to various restoration materials is a prerequisite and investigated in this study.
Methods: Materials tested were Maxcem™Elite (Kerr), Clearfil™SA Cement (Kuraray), RelyX Unicem Clicker and experimental handmix self-adhesive resin cement (both 3M ESPE).
For shear bond strength (SBS) testing, gold, titanium, glass ceramics (ParadigmC, 3M ESPE) and alumina blocks were pre-treated as recommended by cement manufacturers. Stainless steel rods (diameter 4mm) were cemented under pressure (20 g/mm2) onto restoration material discs. After light-curing following the manufacturers' instructions, specimens were stored for 24h at 36°C and 100% relative humidity. Half of the specimen were artificially aged (5.000 thermocycles, 5°C-55°C, 30sec dwell time). SBS was measured using a universal testing machine (Zwick Z010, crosshead speed: 0.75 mm/min).
Data obtained were analyzed using Multiple Range Test (Fisher's LSD; p<0.05).
Results: see table. Values in one column marked with the same superscript characters are not statistically different
| Gold sc | Titanium sc | ParadigmC lc | Al2O3 sc | Al2O3 lc | ||||||
24h | +TC | 24h | +TC | 24h | +TC | 24h | +TC | 24h | +TC | ||
Clearfil SA Cem. | 22,0±5,9c | 20,4±3,1b,c | 35,6±1,7b | 38,2±4,1a | 27,0±10,7b | 31,0±6,2b | 28,2±5,3a,b | 30,2±3,4a | 31,0±4,0b | 24,8±2,3b | |
Maxcem Elite | 20,6±1,1c | 16,7±2,1c | 29,1±2,3c | 29,5±4,2b | 33,9±6,7a,b | 32,0±2,4b | 23,5±2,6b,c | 9,4±11,6c | 20,1±5,8c | 15,8±6,1c | |
EXP | 39,8±3,8a | 30,5±6,2a | 45,3±7,3a | 40,7±1,5a | 40,5±6,5a | 43,6±9,5a | 29,9±6,0a | 35,6±3,6a | 38,7±6,1a | 36,6±5,7a | |
RXU Clicker | 27,6±4,1b | 23,9±2,2b | 32,6±4,3b,c | 32,4±3,5b | 40,7±3,0a | 34,4±5,6b | 21,9±4,6c | 21,4±4,0b | 24,7±2,1c | 25,6±4,8b | |
Conclusion: Experimental handmix self-adhesive cement showed highest adhesion to all restoration materials both after 24h and after artificial aging, followed by RelyX Unicem Clicker and Clearfil SA cement.