Shear Bond Strength Evaluation of Different Veneering Systems on Ni-Cr Alloys

Evaluation and comparison of shear bond strength of porcelain to a beryllium-free alloy of nickel-chromium, nickel and beryllium free alloy of cobalt-chromium, and titanium: An in vitro study

Aims:

The aim of this study was to evaluate and compare the shear bond strength of porcelain to the alloys of nickel-chromium (Ni-Cr), cobalt-chromium (Co-Cr), and titanium.

Materials and Methods:

A total of 40 samples (25 mm × 3 mm × 0.5 mm) were fabricated using smooth casting wax and cast using Ni-Cr, Co-Cr, and titanium alloys followed by porcelain buildup. The samples were divided into four groups with each group containing 10 samples (Group A1–10: sandblasted Ni-Cr alloy, Group B1–10: sandblasted Co-Cr alloy, Group C1–10: nonsandblasted titanium alloy, and Group D1–10: sandblasted titanium alloy). Shear bond strength was measured using a Universal Testing Machine.

Statistical Analysis Used:

ANOVA test and Tukey's honestly significance difference post hoc test for multiple comparisons.

Results:

The mean shear bond strength values for these groups were 22.8960, 27.4400, 13.2560, and 25.3440 MPa, respectively, with sandblasted Co-Cr alloy having the highest and nonsandblasted titanium alloy having the lowest value.

Conclusion:

It could be concluded that newer nickel and beryllium free Co-Cr alloys and titanium alloys with improved strength to weight ratio could prove to be good alternatives to the conventional nickel-based alloys when biocompatibility was a concern.

Shear Bond Strength of Different Repair Systems to Titanium After Water Aging

This study evaluated the shear bond strength (SBS) and stability of commercially pure titanium (CP Ti)/repair material interfaces promoted by different repair systems. One hundred CP Ti cast discs were divided into five repair system groups: 1) Epricord (EP); 2) Bistite II DC (BT); 3) Cojet (CJ); 4) Scotchbond Multi-Purpose Plus (SB) (control group); and 5) Cojet Sand plus Scotchbond Multi-Purpose Plus (CJSB). The specimens were stored in distilled water for 24 hours at 37°C, thermal cycled (5000 cycles, 5°-55°C) and stored under the same conditions for either 24 hours or six months (n=10). SBS was tested and the data were analyzed by two-way analysis of variance (ANOVA) and Tukey test (α=.05). Failure mode was determined with a stereomicroscope (20×). The repair system, storage time, and their interaction significantly affected the SBS (p<0.001). At 24 hours, CJSB exhibited the highest SBS value, followed by CJ. At six months, these two groups had similar mean SBS (p>0.05) and higher means in comparison to the other groups. For both storage times, BT presented the lowest SBS, while the EP and SB groups did not differ significantly from one another (p>0.05). There were no significant differences in SBS between the storage times for the groups EP and CJ (p>0.05). The groups BT, SB, and CJSB showed 100% adhesive failure, irrespective of storage time. The CJSB group showed the highest SBS at both storage times. At six months, the CJ group exhibited a similar SBS mean value when compared to the CJSB group. Water storage adversely affected the groups BT, SB (control group), and CJSB. Considering SBS values, stability, and the failure mode simultaneously, the CJ group showed the best CP Ti repair performance.

Reparability of Aged Silorane With Methacrylate-Based Resin Composite: Micro-Shear Bond Strength and Scanning Electron Microscopy Evaluation

Aged silorane composite restorations can be repaired with a methacrylate-based resin composite by using a phosphate-methacrylate–based adhesive as the intermediate layer.

The effect of surface treatment on bond strength of layering porcelain and hybrid composite bonded to zirconium dioxide ceramics

PURPOSE

The purpose of this study was to investigate the differences between Rocatec (as surface treatment) and #600 polishing (as control) on shear bond strength of layering porcelain and hybrid composite to zirconium dioxide ceramics.

METHODS

Manufactured zirconia blocks used in this study were yttrium partially stabilized zirconia (YTZ(®)), and veneering materials were NobelRondo Zirconia Dentin A2 High Value (NZR) and Estenia C&B (ES). Total 48 zirconia blocks were fabricated (10 mm × 10 mm × 20 mm). The blocks of 24 each were treated by Rocatec and #600 paper, respectively. Surface treated zirconia blocks were divided into two groups, according to veneering materials of NZR and ES. NZR was fired and ES was polymerized to zirconia. The fabricated specimen was fixed to mounting jig and applied shear force using the universal testing machine at a crosshead speed of 0.5 mm/min. All results were statistically analyzed by two-way ANOVA and Tukey's test. EPMA analysis and SPM analysis of specimen interface were carried out.

RESULTS

Mean shear bond strength of each condition was: NZR/#600; 23.3 (S.D. ±7.0) MPa, NZR/Rocatec; 26.9 (S.D. ±7.0) MPa, ES/#600; 10.7 (S.D.±2.4) MPa, ES/Rocatec; 12.5 (S.D.±0.8) MPa.

CONCLUSIONS

From the results of this study, shear bond strength of layering porcelain to zirconia was higher than that of restorative hybrid resin. However the more study will be needed, the appropriate choice of materials became the gides to the expansion of the applied cases of metal-free prothesis.

Adhesive bonding of resin composite to various Ni-Cr alloy surfaces using different metal conditioners and a surface modification system

PURPOSE

This study evaluated the effect of three metal conditioners [Metal Photo Primer (MPP), Cesead II Opaque Primer (OP), Targis Link (TL)], and one surface modification system [Siloc (S)] on the shear bond strength (SBS) of a prosthetic composite material to Ni-Cr alloy.

MATERIALS AND METHODS

Rivet-shaped specimens were cast, and three surface treatments were evaluated: Polishing (P); sandblasting with either 50 microm (50SB) or 250 microm (250SB) Al(2)O(3). All products were applied to half of the specimens, while the other half remained without the materials. Veneering resin composite (8-mm diameter, 2-mm thick) was applied and light-exposed for 90 seconds in a laboratory light-curing unit. The specimens were stored in water at 37 degrees C for 24 hours, and half were subjected to 500 thermal cycles consisting of water baths at 4 degrees C and 60 degrees C. All specimens were submitted to SBS test (0.5 mm/min) until failure. Failure patterns were determined using optical and scanning electron microscope (SEM) analysis. Data were analyzed by ANOVA and post hoc Tukey's test (preset alpha of 5%).

RESULTS

The SBS values of OP and TL groups were higher than those of MPP and S within the 50SB treatment (p < 0.05). No significant difference in SBS was noted between OP and TL as well as between MPP and S. On the other hand, no significant differences were found among conditioners within the 250SB group (p > 0.05). The SBS values of MPP, OP, and S from the 250SB group were higher than those from 50SB (p < 0.05). No significant difference in SBS was noted among most groups with conditioners after thermocycling. The only exception was observed for MPP, which showed an increase in SBS after thermocycling (p < 0.05). Differences in SBS were noted among the groups with conditioners (p < 0.05), and no significant difference in SBS was noted between TL and OP groups, which showed the highest values among all within the P group. No significant difference was noted between MPP and S. Debonded surfaces showed adhesive failures predominantly located between metal surface and opaque resin.

CONCLUSIONS

The OP and TL conditioners and surface sandblasting with 250 microm Al(2)O(3) promoted the highest SBS between resin and the Ni-Cr metal surface.

Comparative study of chemical and mechanical retentive systems for bonding of indirect composite resin to commercially pure titanium

This study evaluated the effect of chemical and mechanical surface treatments for cast metal alloys on the bond strength of an indirect composite resin (Artglass) to commercially pure titanium (cpTi). Thirty cylindrical metal rods (3 mm diameter x 60 mm long) were cast in grade-1 cpTi and randomly assigned to 6 groups (n=5) according to the received surface treatment: sandblasting; chemical treatment; mechanical treatment - 0.4 mm beads; mechanical treatment - 0.6 mm beads; chemical/mechanical treatment - 0.4 mm; and chemical/mechanical treatment - 0.6 mm beads. Artglass rings (6.0 mm diameter x 2.0 mm thick) were light cured around the cpTi rods, according manufacturer's specifications. The specimens were invested in hard gypsum and their bond strength (in MPa) to the rods was measured at fracture with a universal testing machine at a crosshead speed of 2.0 mm/min and 500 kgf load cell. Data were analyzed statistically by one-way ANOVA and Tukey test (alpha=5%). The surface treatments differed significantly from each other (p<0.05) regarding the recorded bond strengths. Chemical retention and sandblasting showed statistically similar results to each other (p=0.139) and both had significantly lower bond strengths (p<0.05) than the other treatments. In conclusion, mechanical retention, either associated or not to chemical treatment, provided higher bond strength of the indirect composite resin to cpTi.