Microtensile Bond strength of glass-fiber posts with self-adhesive resin cements

Purpose: This study evaluated the microtensile bond strength (”TBS) of two glass fiber posts to intraradicular dentin cemented with two self-adhesive resin cements and two self-etching resin cements (control). Methods: Forty-eight single-rooted human teeth were decoronated, endodontically-treated, post-space prepared and divided into 8 groups. Glass fiber posts used were: Exacto/Angelus, Brazil (EA) and EverStich/StichTech, Finland (ES), which were cemented with self-adhesive resin cement BisCem/Bisco (BIS), RelyX Unicem/3M ESPE (UNI) and self-etching adhesive resin cements NAC100/Kuraray (NAC) and Panavia F/Kuraray (PAN) as a control. Specimens were thermocycled for 1000 cycles in water baths 5șC - 55șC and then stored in water at 37șC for 1 month. Specimens were then horizontally-sectioned into 4 slices, 1.0mm thick, from cervical root region. This resulted in 24 sticks/group (n=24). These were subjected to tensile testing in a special testing machine (BISCO). Mean ”TBS and SDs were calculated and data statistically-analyzed by ANOVA and Tukey's. Results: Means and SDs of ”TBS (MPa) were: EA/PAN: 10.18 (4.16), EA/NAC: 13.95 (5.04), EA/BIS: 16.36 (4.82), EA/UNI: 19.75 (5.11), ES/PAN: 25.86 (6.13), ES/NAC: 29.05 (6.98), ES/BIS: 28.84 (5.95), ES/UNI: 30.51 (6.55). ANOVA indicated significant differences among the groups (P<0.0001). Mean ”TBS values obtained with ES post were significantly higher than those obtained with EA. Bond strength of Panavia F (control) was consistently lower than other cements, however, without statistical significance (P>0.05), except when compared with Rely-X Unicem, which showed significant difference (p<0.001). Conclusions: Everstich posts resulted in highest mean ”TBS values with all cements. One self-adhesive cement (Rely-X Unicem) showed higher bond strength than the other as well as the two control cements. Acknowledgments: Materials provided by Sticktech, Finland; Angelus, Brazil; Kuraray, Japan; 3M-ESPE, Bisco.