Different surface treatments and adhesive monomers for zirconia-resin bonds: A systematic review and network meta-analysis

This review examined the efficacy of surface treatments and adhesive monomers for enhancing zirconia-resin bond strength. A comprehensive literature search in PubMed, Embase, Web of Science, Scopus, and the Cochrane Library yielded relevant in vitro studies. Employing pairwise and Bayesian network meta-analyses, 77 articles meeting inclusion criteria were analyzed. Gas plasma was found to be ineffective, while treatments including air abrasion, silica coating, laser, selective infiltration etching, hot etching showed varied effectiveness. Air abrasion with finer particles (25-53 µm) showed higher immediate bond strength than larger particles (110-150 µm), with no significant difference post-aging. The Rocatec silica coating system outperformed the CoJet system in both immediate and long-term bond strength. Adhesives containing 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) were superior to other acidic monomers. The application of 2-hydroxyethyl methacrylate and silane did not improve bonding performance. Notably, 91.2 % of bonds weakened after aging, but this effect was less pronounced with air abrasion or silica coating. The findings highlight the effectiveness of air abrasion, silica coating, selective infiltration etching, hot etching, and laser treatment in improving bond strength, with 10-MDP in bonding agents enhancing zirconia bonding efficacy.

Effects of Different Primers on the Bond Strength to Properly and Excessively Etched Ceramic-coated Zirconia

PURPOSE

To determine the effects of various primers on the immediate and long-term bond strength of ceramic-coated ultratranslucent zirconia that is properly or excessively etched.

METHODS AND MATERIALS

Ceramic-coated zirconia plates were etched with 9.5% hydrofluoric acid (HF) for 2 or 5 minutes, after which the surface morphology and elemental composition were examined. The etched specimens were treated with different primers including methacryloyloxydecyl dihydrogen phosphate (MDP)-only containing primer, silane-only containing primer, MDP and silane-containing ceramic primer as well as MDP and silane-containing adhesive system. For surface contact angle and shear bond strength (SBS) data, the difference between groups was evaluated by one-way analysis of variance (ANOVA) and three-way ANOVA factorial analysis, respectively. The statistical significance level of 0.05 was set and the Tukey test and the Dunnett-T3 test were used for post-hoc multiple comparisons.

RESULTS

Excessive etching (9.5% HF for 5 minutes) led to overconsumption of the glass layer and exposure of zirconia substrate compared to proper etching (9.5% HF for 2 minutes). Among different primers, the surface contact angle of the silane-only containing primer group was the lowest. The silane-only containing primer and MDP and silane-containing ceramic primer produced higher shear bond strength of properly and excessively etched ceramic-coated zirconia, respectively, both before and after thermal aging.

CONCLUSIONS

The silane-only containing primer and MDP and silane-containing primer can obtain better immediate and long-term shear bond strength for properly and excessively etched ceramic-coated zirconia, respectively.

Shear bond strength between gingival composite resin and glazed gingival porcelain for implant-supported prostheses

This study determined the shear bond strength (SBS) between an indirect gingival composite resin and glazed gingival porcelain after various surface treatments. A total of 176 porcelain disks with natural glazing were used and assigned to one of four groups: no surface treatment, airborne-particle abrasion, hydrofluoric acid etching, or a combination of airborne-particle abrasion followed by hydrofluoric acid etching. Each group was divided into two subgroups: one subgroup was unprimed, and the other was silanized. An indirect composite resin was then bonded to the porcelain disks. Half of the specimens in each group (n = 11) were exposed to 5000 thermocycles. SBSs were measured, and data were analyzed with the Kruskal-Wallis and Steel-Dwass tests. Among silanized specimens, those treated with the combination of airborne-particle abrasion and hydrofluoric acid etching exhibited the highest bond strengths both before and after thermocycling. However, the SBS values of the silanized and unprimed hydrofluoric acid etched specimens did not differ significantly. Airborne-particle abrasion followed by hydrofluoric acid etching with silane application yielded stronger, more durable bonds between the indirect gingival composite resin and glazed gingival porcelain.

High bonding strength between zirconia and composite resin based on combined surface treatment for dental restorations

Zirconia is the preferred material for dental restorations; however, dental restorations are usually affected by zirconia fractures due to chipping and delamination of the veneer ceramic. One effective solution for repairing chemically inert zirconia frameworks is to strongly chemically bond them with the composite resin via surface modification. Thus, the bonding strength between the zirconia and composite resin determines the performance of dental restoration. Herein, we investigate the shear bond strength between zirconia ceramic and two ceramic repair systems before and after thermal cycling based on different surface pretreatments, including air-abrasion and a novel silane coupling agent. When treated with combined sandblasting, novel silane and 10-methacryloyloxydecyl hydrogen phosphate act as a bonding agent for the zirconia surface, and the maximum shear bond strength achieves 27.5 MPa, as measured by a universal testing machine through the average of 16 separate measurements. The results show that the combined treatment resists the interface damage caused by expansion and contraction during thermal cycling. The long-term bond durability is due to the micro-mechanical bond force formed by resin and ceramic, and the chemical bonds of Zr-O-Si at the interface. Results indicate that selective pretreating the surface results in high bond strength between the zirconia and the composite resin, which is meaningful to optimize dental restoration.

Effect of glazing application side and mechanical cycling on the biaxial flexural strength and Weibull characteristics of a Y-TZP ceramic

Glaze application on monolithic zirconia (Y-TZP) can be a practical approach to improve the mechanical properties of this material.