Abstract

MIORANDO, Bruna et al. Bond strength of intra-canal posts cemented with different materials. RFO UPF [online]. 2011, vol.16, n.2, pp. 166-171. ISSN 1413-4012.

Objective: the objective of this paper is to evaluate the bond strength (σ) of intra-canal posts (P) cemented with resin cement (RC- RelyX ARC) and resin-modified glass ionomer cement (RMGIC- RelyX Luting 2), testing the hypothesis that glass fiber (GF) P produce greater σ  values than other types of P, regardless the cement used. Methods: one hundred anterior teeth were endodontically treated, prepared for a 12-mm post space and randomly divided into 5 groups according to P type: MPmetallic P; CFP- carbon fiber P; GFA- GFP; GFF- GFP; GFC- CFP coated with GF. The posts were cemented in prepared root canals, using either RC or RMGIC (n = 10). Teeth roots were cut into three 3-mm-thick slices. The central slice from each root was submitted to a push-out test and the maximum load (F) was recorded. The bonding area (A) was calculated and the σ (F/A) values were statistically analyzed, using Anova and Tukey (a = 0.05). Results: mean σ values (MPa) and statistical groupings of posts cemented with RC and RMGIC were, respectively: MP- 1.2 ± 0.4E and 2.2 ± 0.5B; CFP- 1.3 ± 0.4E and 1.4 ± 0.3E; GFA- 2.0 ± 0.6BC and 1.8 ± 0.5CD; GFF- 1.7 ± 0.4CD and 0.7 ± 0.3F; GFC- 2.5 ± 0.5B and 3.6 ± 0.7A. The MP and CFP showed the lowest mean σ values (p < 0.05) when cemented with RC, which can be explained by the chemical adhesion between the RC and silane treated GFP (GFA, GFF, GFC). The grooved P (GFC) cemented with RMGIC showed the greatest mean σ value. Conclusion: mechanical and chemical retentive methods are adhesion mechanisms that can synergistically work to cement posts using RMGIC and RC.

Keywords : Luting cement.; Posts.; Glass ionomer cement.; Resin cement..