In vitro evaluation of the retention of zirconia-based ceramic posts luted with glass ionomer and resin cements

Abstract

The retention of zirconia-based ceramic posts (CosmoPost system) luted with glass ionomer and resin cements was evaluated. Thirtytwo extracted, caries-free, unrestored teeth were selected and stored in chlorhexidine and water solution. The teeth were endodontically treated and randomly assigned to two groups (n=16). Each tooth was decoronated and prepared to a depth of 10.0 mm from root surface to receive a 1.4 mm diameter zirconium dioxide post. Each group had posts cemented with either glass ionomer cement (Fuji I) or resin cement (Variolink II). The post/teeth specimens were embedded in resin blocks and subjected to tensile testing. The tensile force required to dislodge the cemented posts in a tensile testing machine was recorded. The mean stress values of both groups were analyzed for statistical differences using ANOVA and Student's t-test. Significance level was set at 5%. Mean peak forces at failure (N) and standard deviation for the tested cements were the following: Fuji I = 121.8 (±17.4) and Variolink II = 228.1 (±36.8). Posts luted with the resin cement presented statistically significant higher tensile bond strength than those retained with glass ionomer (p<0.05). It may be concluded that zirconia posts cemented with resin-based cement (Variolink II) failed at statistically significant higher values compared to those cemented with glass ionomer cement (Fuji I). Regardless of the cement type, the posts failed adhesively at the cement/post interface when subjected to a tensile force.

Zirconia ceramic post systems: a literature review and a case report

“…With regard to the reduction in bond strength values when push-out testing was used, it was caused by internal stresses at the dentin-post interface 72) . On the influence of luting agents upon retentive strength, Table 3 also shows that zirconia posts bonded to teeth with resin cements exhibited higher retentive strengths than with glass ionomer (GI) cements 70,71) .…”

“…2. Retentive strength of zirconia posts The retentive strength of zirconia posts was examined using natural teeth in 11 studies 63,65,66,[70][71][72][73]77,[80][81][82] (Table 3) and in artificial post spaces using different luting agents in five studies 68,[74][75][76]79) (Table 4). The bond strength of zirconia posts to different core materials was also examined in six studies 64,67,69,78,81,83) (Table 5), thus making it a total of 21 studies .…”

“…The bond strength of zirconia posts to different core materials was also examined in six studies 64,67,69,78,81,83) (Table 5), thus making it a total of 21 studies . On the influence of bond strength evaluation method, Table 3 shows that the bond strength of zirconia posts to natural teeth ranged between 123 N and 436 N with tensile testing 70,71,73,81) . With push-out tests, lower values in the range of 1.4−7.7 MPa were obtained instead 63,66,72) .…”

Effect of Surface Treatments on Leakage of Zirconium Oxide Ceramics

“…In addition to that, in resin cementation, the possibility of fracture of the restoration and the supportive tooth is decreased compared to the conventional bisphenol-A-glycidyl dimethacrylate (Bis-GMA) containing cements. Therefore, many investigators recommended the usage of adhesive resin-based cement in the regions where adhesion is important because of the strong occlusal forces (10,(31)(32)(33)(34). In their study which focused on alumina disks infiltrated with glass, Kern and Thompson (35), have reported that the adhesive resistance of samples cemented with Bis-GMA composite resin had lower bond strength than the samples bonded with MDP-containing composite resin.…”

Fatigue Behavior of the Resinous Cement to Zirconia Bond

“…Resinous cements have stronger tensile and shear bond strengths to zirconia than other cement types, making them the preferred choice for clinical use . However, several bond strength studies have reported that adhesive failures have occurred at the resin/zirconia interface, rather than at the cement/dentin interface .…”