Impact of Gluma Desensitizer on the tensile strength of zirconia crowns bonded to dentin: an in vitro study

Abstract

This study tested the impact of Gluma Desensitizer on the tensile strength of zirconia crowns bonded to dentin. Human teeth were prepared and randomly divided into six groups (N = 144, n = 24 per group). For each tooth, a zirconia crown was manufactured. The zirconia crowns were cemented with: (1) Panavia21 (PAN), (2) Panavia21 combined with Gluma Desensitizer (PAN-G), (3) RelyX Unicem (RXU), (4) RelyX Unicem combined with Gluma Desensitizer (RXU-G), (5) G-Cem (GCM) and (6) GCem combined with Gluma Desensitizer (GCM-G). The initial tensile strength was measured in half (n = 12) of each group and the other half (n = 12) subjected to a chewing machine (1.2 Mio, 49 N, 5°C/50°C). The cemented crowns were pulled in a Universal Testing Machine (1 mm/min, Zwick Z010) until failure occurred and tensile strength was calculated. Data were analyzed with one-way and two-way ANOVA followed by a post hoc Scheffé test, t test and Kaplan-Meier analysis with a Breslow-Gehan analysis test ( = 0.05). After the chewing simulation, the self-adhesive resin cements combined with Gluma Desensitizer showed significantly higher tensile strength (RXU-G, 12.8 ± 4.3 MPa; GCM-G, 13.4 ± 6.2 MPa) than PAN (7.3 ± 1.7 MPa) and PAN-G (0.9 ± 0.6). Within the groups, PAN, PAN-G and RXU resulted in significantly lower values when compared to the initial tensile strength; the values of all other test groups were stable. In this study, self-adhesive resin cements combined with Gluma Desensitizer reached better long-term stability compared to PAN and PAN-G after chewing simulation.

The effect of dentin desensitizers and Nd:YAG laser pre-treatment on microtensile bond strength of self-adhesive resin cement to dentin

“…Additionally, Sailer et al28 showed statistically increased shear bond strength values when glutaraldehyde/HEMA containing desensitizer was applied before self-adhesive cement luting. Moreover, Stawarczyk et al23 showed increased shear bond strength values even after aging procedures and also it has been revealed that Gluma had a positive effect on the tensile bond strength of self adhesive resin cements even with chewing simulations 30. These results are in agreement with the findings of the current study.…”

“…Hitz18 et al showed the negative impact of thermocycling on bond strength of dentin and self-adhesive resin cement interface. Contrary to these findings, Sailer et al28 showed predominantly cohesive failure despite the absence of the thermocycling process; indicating the cement itself was the weakest link and Stawarczyk et al30 also showed cohesive failure before and after aging procedures.…”

“…A limited number of studies have evaluated the impact of Gluma on the self-adhesive resin-dentin interface 23,28,29,30. Sailer et al29 showed that glutaraldehyde-containing dentin desensitizer and bonding agent (Gluma and Syntac) tended to positively influence the shear bond strength of the self-adhesive resin cement (RelyX U200) to dentin.…”

Effect of surface conditioning with airborne-particle abrasion on the tensile strength of polymeric CAD/CAM crowns luted with self-adhesive and conventional resin cements

“…The size of the specimen (n=12 per subgroup) was based on a previous study, which showed significant differences with a similar specimen size. 13 No formal power analysis was performed prior to initiation of the study. The cements were occlusal photopolymerized for 30 s (Elipar S10, 3M ESPE).…”

“…However, the teeth were prepared manually, and the water supply was not controlled with the handpiece as under clinical conditions. In a previous study, where the tensile strength of zirconia crowns cemented with selfadhesive resin cements on dentin were tested, 13 the results ranged between 7.3 MPa and 14.1…”