Methods: Materials used were RelyX Luting Plus cement (RLP, 3M ESPE), FujiCEM (FC, GC), and Nexus RMGI (NX-R, Kerr). Cements were dispensed per IFU and applied to Ti and bovine dentin substrates thru PTFE molds. Samples were cured at 37oC and relative humidity of 95% for 1hr followed by storage in 37oC DI water for 23 hrs. Notched edge shear bond strength was tested on Instron. Also, fluoride release from three cured discs (20 x 1 mm) of each product in 37C deionized water was measured after 1, 7, 14, 28, 59 days using fluoride selective electrode and TISAB buffer solution.
Results: The mean values for Ti and bovine dentin adhesion and cumulative fluoride release, including their standard deviations, are summarized in the following table:
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|
|
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Cumulative Fluoride Release after Days (μg F/g sample) |
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Material |
Delivery System |
Adhesion to titanium, MPa |
Adhesion to Dentin, MPa |
1 |
7 |
14 |
28 |
59 |
RLP |
Automix Paste/Paste |
10.2 (0.7) |
6.7 (1.0) |
765+31 |
1592+51 |
2143+57 |
2808+68 |
3602+69 |
FC |
Automix Paste/Paste |
8.8 (1.4) |
2.2 (1.8) |
1040+101 |
1982+129 |
2610+135 |
3368+144 |
4417+173 |
NX- R |
Automix Paste/Paste |
9.0 (2.0) |
8.7 (1.6) |
247+7 |
531+10 |
699+11 |
905+12 |
1195+13 |
Conclusion: ANOVA analysis was performed at p < 0.05 per Tukey’s pair wise comparison test. FC showed statistically lower bond strength to dentin compared to other cements. There was no significant difference in bond strength to Ti for all cements. RLP and FC released significantly higher amounts of fluoride than NX-R at all measurement times.