Rocatec Plus Research Articles

Effect of different surface treatments on the shear bond strength of PAEKs to composite resin

The present study aimed to evaluate the effects of surface treatment techniques on the shear bond strength (SBS) of Polyetheretherketone (PEEK) and Polyetherketoneketone (PEKK) polymers to composite resin. Eighty-eight rectangular (7 × 7×2 mm) specimens were prepared for each polymer and randomly divided into eight groups (n = 11): untreated (Cnt); treated with non-thermal plasma (Pls); etched with 98% sulfuric acid (Sa); tribochemical silica-coated with Cojet (Tb30); tribochemical silica-coated with Rocatec Plus (Tb110); 98% sulfuric acid + plasma (Sa_Pls); Cojet + plasma (Tb30_Pls); Rocatec Plus + plasma (Tb110_Pls). One specimen from each group was randomly selected for scanning electron microscope analysis. After the bonding agent and an opaquer were applied, composite resin cylinders were built on the specimens. SBS test was performed after water storage, and data were statistically analyzed by 2-way analysis of variance and Tukey’s multiple comparison tests (α = 0.05). The failure-modes were examined. 2-way ANOVA showed that the surface treatment and its interaction between polymer type were significant on SBS values (p < 0.001). Among the PEEK groups, Group Sa (22.55 ± 2.01 MPa) showed the highest SBS value, but no significant difference was observed between Group Tb30, Group Sa_Pls, and Group Tb30_Pls (p > 0.05). Within the PEKK groups, Group Tb30_Pls (22.33 ± 1.19 MPa) showed the highest SBS value, but no significant difference was observed between Group Tb30 and Group Tb110_Pls (p > 0.05). Surface treatments with non-thermal plasma, 98% sulfuric acid and tribochemical silica-coating on PEEK and PEKK increase the bond strength with composite resin. Between the PEEK and PEKK polymers, tested surface treatment effects were significantly different except for the tribochemical silica-coating.

Effect of airborne-particle abrasion of a titanium base abutment on the stability of the bonded interface and retention forces of crowns after artificial aging

Statement of problemPublished data have shown that a mechanical surface treatment of titanium surfaces increases bonding potential. However, most of the studies are based on shear or tensile tests performed on flat-surfaced specimens and do not take into consideration the retention given by the titanium base (ti-base) axial walls and the thermomechanical loading seen in a clinical setting. PurposeThe purpose of this in vitro study was to evaluate the influence of different airborne-particle abrasion (APA) methods of the ti-base surface on the stability of the bonded interface and retention forces between these titanium bases and lithium disilicate crowns after thermomechanical aging. Material and methodsSixty internal connection implants (Conelog) were restored with lithium disilicate crowns and bonded to the corresponding ti-bases (Conelog). The ti-bases were divided into 4 groups (n=15), 3 experimental groups applying different APA methods, 30-μm silica-modified Al2O3 particles (CoJet) (30-SiO-AlO), 50-μm Al2O3 (Cobra Aluoxyd) (50-AlO), 110-μm silica-modified Al2O3 particles (Rocatec Plus) (110-SiO-AlO), and 1 control group (NoT). Ti-bases were airborne-particle abraded (10 seconds, 0.25 MPa at a 10-mm distance) under standardized conditions in a custom-made APA device. All crowns were cemented with a resin cement (Multilink Hybrid Abutment). After aging (1 200 000 cycles, 49 N, 1.67 Hz; 5 °C-55 °C, 120 seconds), all specimens were assessed for the presence of bond failures by optical microscopy (×50). The retention forces (N) were tested by using a pull-off test (0.5mm/min). Modes of failure were classified (Type 1, 2, or 3). An additional ti-base representing each group was prepared for surface roughness (μm) calculation (Ra, Rc, Rz) with a noncontact laser profilometer, and representative scanning electron microscope (SEM) images were recorded (×1000). Chi-squared tests were performed to analyze the bonded interface failure and modes of failure, and a Kruskal-Wallis test was selected to evaluate retention force values (α=.05). ResultsThe percentages of bonding failure after aging were 73.3% (NoT), 40% (30-SiO-AlO), 6.7% (50-AlO), and 40% (110-SiO-AlO). The stability of the bonded interface was influenced by the APA method applied (P<.05). Mean ±standard deviation retention force values varied from 206.3 ±86.3 N (NoT) to 420 ±139.5 N (50-AlO), and the differences between these 2 groups were significant (P<.05). Modes of failure were predominantly Type 2 (30-SiO-AlO; 50-AlO; 110-SiO-AlO) and Type 3 (NoT). ConclusionsAirborne-particle abrasion of the titanium surface increased the bond stability and retention forces between the ti-base and the respective crown. The use of 50-μm Al2O3 provided the most stable bonded interface among the different treatments.

The effect of repeated surface treatment of zirconia on its bond strength to resin cement.

PURPOSEThe aim of this study is to evaluate the influence of repeated surface treatments on wettability and surface roughness for zirconia surface and bond strength of zirconia-based ceramics to resin cement.MATERIALS AND METHODSSeventy blocks (10 × 10 × 3 mm) of zirconia-based ceramics were fabricated and divided into two groups according to the surface treatments: (A) 110 µm Al2O3 airborne-particle abrasion and (R) 110 µm silica modified Al2O3 airborne-particle abrasion. At stage 2, each group was subdivided into 5 groups according to the surface retreatments: (a) 110 µm Al2O3 airborne-particle abrasion, (r) 110 µm silica modified Al2O3 airborne-particle abrasion, (D) diamond bur, (Da) diamond bur + 110 µm Al2O3 airborne-particle abrasion, and (Dr) diamond bur + 110 µm silica modified Al2O3 airborne-particle abrasion. Cylinders of self-adhesive resin cement were cemented onto each treated ceramic surface and subjected to micro-shear bond strength test. Additional specimens were prepared for roughness and wettability analyses. The data were subjected to t-test and One-way ANOVA followed by Tukey's post hoc test (α=.05).RESULTSAt stage 1, group R presented higher bond strength values than group A (P=.000). There was a statistically significant increase of bond strength at stage 2 for group A (P=.003). The diamond bur influenced the surface roughness, increasing the values (P=.023). Group R provided better wettability. Regardless of the applied surface treatment, most of failures were adhesive.CONCLUSIONThe combination of application and reapplication of Rocatec Plus showed the best results of bond strength. Surface retreatment and recementation might be an indicated clinical strategy.

Effect of different air-abrasion protocols on topography, surface wettability and adhesion of MDP monomer-based resin cement to zirconia

This study evaluated the effect of air-abrasion protocols on the topography, surface wettability and adhesion of resin cement to zirconia. Ceramic specimens (N = 49; n = 7) (15 mm × 2 mm) were randomly allocated to seven groups to be treated with: (1) Air-abrasion with 45 μm Al2O3 (A45), (2) 80 μm Al2O3 (A80), (3) 30 μm Al2O3 coated with SiO2 (CoJet) (C30), (4) 30 μm Al2O3 coated with SiO2 (Rocatec Soft) (R30), (5) 110 μm Al2O3 coated with SiO2 (Rocatec Plus) (R110); (6) R110R30 (Rocatec) (R110R30) and (7) control, no conditioning (NC). Air-abrasion was performed using a chairside air-abrasion device (2.5 bar, 10 mm, 90 s). Contact angle measurements were performed using goniometry (n = 5). MDP-based dual resin cement (Panavia F2.0) was bonded on four locations after air-abrasion protocols (n = 20 per group). Half of the specimens were tested after 24 h and the other half after thermal cycling (×3000, 5–55 °C). Data were analyzed using 1-, 2-way ANOVA and Tukey’s test (alpha = 0.05). Significantly lower contact angle values were observed for groups C30 (62.6 ± 0.91), R30 (61.91 ± 1.05) and R110R30 (61.54 ± 1.02) compared to those of other groups (65.5 ± 0.9–110.61 ± 0.9) (p < 0.05). In dry conditions, surface conditioning methods tested did not show significant effect on bond strength (MPa) (10.57 ± 1.42–16.86 ± 2.54) (p = 0.238). After thermocycling, bond strength results decreased significantly (p < 0.05) (12.6–51.2%). R110 (7.18 ± 1.34) and A80 (4.92 ± 1.53) showed significantly higher bond strength compared to other groups (2.13 ± 0.73–4.16 ± 1.34) (p < 0.05). The best wettability and adhesion results with MDP-based resin cement to zirconia was achieved with A80 and R110 air-abrasion.

The effects of surface treatments on tensile bond strength of polyether-ketone-ketone (PEKK) to veneering resin

ObjectivesTo test the different PEKK surface treatment methods on the tensile bond strength (TBS) of a resin composite to PEKK. MethodsTwo hundred and fifty polished PEKK specimens were fabricated, divided into 5 groups (n = 50) and underwent the following treatments: no pre-treatment (control group C), 110 µm Al2O3 gritblasting at 2 bar for 10 s (Group Al), 98 wt% sulfuric acid etching for 60 s (Group SA), tribochemical silica-coating through air-abrasion with Rocatec Plus 110 µm at 2 bar for 10 s (Group Trib), and sulfuric acid etching and subsequent tribochemical silica-coating (Group SATrib). Ten specimens in each group were taken out for surface characterization. On the samples of Groups Trib and SATrib, a silane coupling agent was applied. Then, for all groups, veneering resin stubs (diameter: 3 mm) were bonded on the treated surfaces. Half of the specimens (n = 20) in each group were submitted to thermo-cycling for 7000 cycles between 5 °C and 55 °C. The TBS of all groups was examined using a universal testing machine. Fracture analysis was performed. For statistical analyses, one-way ANOVA (post-hoc: Bonferroni) and t-test were used at α = 0.05. ResultsAlthough the surface treatment methods used in this study were able to increase PEKK surface roughness, none of them showed impact on TBS between PEKK and the resin composite before thermal cycling (p > 0.05). However, after thermo-cycling, significantly higher TBS was measured for Groups Trib and SATrib (p < 0.05). Furthermore, the TBS for the SATrib group was not significantly affected by thermal cycling. Groups SA, Trib and SATrib illustrated an increase of Weibull moduli after thermocycling, but decrease was observed in Groups C and Al. ConclusionDespite low tensile bond strengths were found in all groups in this study, Tribochemical silica-coating through air-abrasion with Rocatec Plus on polished or sulfuric-etched PEKK surface can significantly increase the tensile bonding stability as well as durability of resin composite to PEKK.

Influence of Particle and Air-Abrasion Moment on Y-TZP Surface Characterization and Bond Strength.

To evaluate the influence of particle and air-abrasion on the surface characterization and shear bond strength (SBS) of a Y-TZP ceramic with a resin cement. Y-TZP specimens were air-abraded with 50 μm alumina particles; 120 μm alumina particles; 30 μm silica-coated alumina particles (Rocatec Soft); 110 μm silica-coated alumina particles (Rocatec Plus). Air-abrasion was performed before (BS); after (AS); before and after (BAS) zirconia sintering. Surface characterization included roughness (n = 10), wettability (n = 10), morphology (n = 2), and elemental composition (n = 2). For SBS (n = 11), composite resin discs were bonded to the air-abraded and silane-treated zirconia surface, with the resin cement RelyX ARC. Failure mode was determined. Roughness, wettability, and SBS data were analyzed by two-way ANOVA with pairwise interaction and Tukey's test (α = 0.05). Air-abrasion performed with coarser particles at BS and BAS moments provided the highest roughness values, while the lowest roughness values were observed with particles combined with AS moment (p < 0.01). Rocatec Plus provided lower contact angle than the 120 μm alumina particles (p = 0.013), and BAS exhibited lower contact angle than BS (p = 0.002). The combinations 120 μm/BS and the silica-coated alumina particles/AS and /BAS showed the highest SBS (p < 0.05). The combination of each particle/BAS was statistically similar to the same particle/AS. Failure mode was 100% adhesive for all groups. The interaction particle size/air-abrasion moment determined the morphological pattern. Silicon was observed only in the Rocatec groups. Roughness was influenced by the particle size and was higher when the zirconia was air-abraded in its green stage. The particle composition played an important role in the wettability and both studied air-abrasion moments provided similar wettability than the one in which air-abrasion is usually performed. The highest SBS values were observed in the three moments, by using certain particles for each moment.

Effect of Alumina Particle Size on the Bond Strength between Autopolymerized Acrylic Resin and Commercially Pure Titanium.

To address the following null hypothesis: when the Rocatec bonding system is used, the various sizes of aluminum oxide particles used to roughen the surface area of the commercially pure (CP) titanium prior to bonding to autopolymerized resin have no effect on the average shear bond strength. One hundred specimens were randomly allocated to five equally sized groups: Ti-no air abrasion (group A), Ti-air-abraded with 50 μm (group B), Ti-110 μm (group C), Ti-250 μm (group D), and Co-Cr-50 μm (group E) grain-size aluminum oxide. Rocatec Plus tribochemical coating was applied to all of the specimens, followed by a RelyX primer and Sinfonyopaquer. Autopolymerized denture base resin was then bonded to the treated titanium surfaces. All specimens underwent thermocycling (10,000 cycles), shear bond testing, and mode of failure examination under stereoscopic microscopy. The average bond strength of group D (250 μm) was significantly different compared to all other groups, except group C (p = 0.057, trending significance). The average bond strength of group D was substantially higher than that in the other groups (p < 0.01). The weakest bond was observed when the specimens did not receive any air abrasion (group A). Maximum load (N) showed the same significant results as the shear bond strength at maximum load (MPa). The average extension at maximum load (mm) and the time at maximum load(s) for group A were significantly different than that of all other groups. Group A had lower average values than any other group (p = 0.003). More cohesive and mixed, rather than adhesive, modes of failure were observed as the size of the aluminum oxide particles increased. When the Rocatec system is used, using a combination of chemical and micromechanical adhesion is essential for the success of the bond between the autopolymerized acrylic resin and CP Ti. The micromechanical interlock can be improved significantly when the Ti surface is air abraded with larger particles (250 μm) than the currently used alumina particle size.

Bond Strenght of Zirconia Submitted to Different Surface Treatments

Objective: To evaluate the shear bond strength of a recent adhesive system used in the cementation of zirconia. Material and Methods: Overall, 72 zirconia specimens (Zirconzhan) were divided and randomized into 3 groups according to the type of surface treatment: G1 no treatment + adhesive system; G2 blasted with aluminum oxide + adhesive system and G3 tribochemical treatment (Rocatec Plus) + adhesive system. Half of each group (n = 12) had bond strength evaluated on two occasions: 24 hours after cementation, kept stored in distilled water at 37 ° C without thermal cycling, and after thermal cycling (5000 cycles, 5°C-55°C). Data were analyzed by ANOVA with Tukey's post-test (α≤0.05). Results: At first moment, G1 and G3 showed higher bond strength (8.64 ± 3.43 MPa and 6.55 ± 2.27 MPa) compared to G2, with no statistically significant difference between them. After thermal cycling, G3 showed higher bond strength (7.70 ± 1.82 MPa). Conclusion: Initially, only the adhesive system promoted higher bond strength, but after thermal cycling,bond strength decreased. The best treatment to promote high bond strength to zirconia is to associate tribochemical treatment with the adhesive system; most failures observed after thermal cycling were mixed and cohesive, showing a mechanical imbrication of the adhesive system, suggesting that there is no chemical bond; and the surface of the group with greater bond strength after thermal cycling showed more surface irregularities compared to the other groups.

Effect of surface treatments on the shear bond strength of luting cements to Y-TZP ceramic

Statement of problemBecause zirconia is a glass-free material, alternative surface treatments such as airborne-particle abrasion or silica coating should be used for long-term bonding. However, these surface treatments in combination with different bonding agents and luting cements have not yet been studied. PurposeThe purpose of the study was to evaluate the effect of surface treatments on the shear bond strength (SBS) of luting cements to Y-TZP ceramic. Material and methodsZirconia disks (N=240) were airborne-particle abraded with the following particles (n=48): 50 μm Al2O3; 120 μm Al2O3; 30 μm silica-coated Al2O3 (Rocatec Soft); 120 μm Al2O3+110 μm silica-coated Al2O3 (Rocatec Plus); and Rocatec Plus. After silanization of the zirconia surface, composite resin disks were bonded with (n=12) RelyX Luting 2; RelyX ARC; RelyX U100; and Panavia F. The bonded specimens were thermocycled (10 000 cycles) and tested for SBS. Failure mode was determined with a stereomicroscope (×20). The morphology and elemental composition of airborne-particle abraded surfaces were evaluated with scanning electron microscopy (×500) and energy-dispersive x-ray spectroscopy (×50). ResultsSurface treatments, cements, and their interaction were significant (P<.001). For RelyX ARC, Rocatec Soft and Rocatec Plus provided the highest SBS. In general, surface treatments did not influence the SBS of RelyX U100 and Panavia F. Regardless of the cement, no significant difference was found between 50 μm and 120 μm Al2O3 particles, between Rocatec Soft and Rocatec Plus, or between Rocatec Plus and 120 μm Al2O3 particles+Rocatec Plus. All groups showed adhesive failures. Different particle sizes provided differences in morphological patterns. The elemental composition comprised Al and Al/Si for alumina and silica-abraded zirconia. ConclusionsParticle size did not influence the SBS of the groups abraded exclusively with alumina or silica-coated particles. RelyX ARC was more surface-treatment dependent than RelyX U100 or Panavia F.

Effect of surface and heat treatments on the biaxial flexural strength and phase transformation of a Y-TZP ceramic.

To evaluate the effect of grinding and airborne-particle abrasion on the biaxial flexural strength (BFS) and phase transformation of a Y-TZP ceramic, and examine whether sintering the veneering porcelain renders the previous heat treatment recommended by the manufacturer unnecessary. Lava zirconia specimens (N = 108) were obtained with the following dimensions: 14.0 mm diameter × 1.3 mm thickness (n = 36) and 14.0 mm × 1.6 mm (n = 72). The thicker specimens were ground with diamond burs under irrigation and received (heat-treated groups) or not (non-heat-treated groups) a heat treatment (1000°C for 30 min) prior to the four firing cycles applied to simulate the sintering of the veneering porcelain. All specimens were air abraded as follows (n = 12): 1) 30-μm silica-modified Al₂O₃particles (Rocatec Soft); 2) 110-μm silica-modified Al₂O₃particles (Rocatec Plus); and 3) 120-μm Al₂O₃particles, followed by Rocatec Plus. Three specimens of each group were analyzed by x-ray diffraction (XRD) to assess the monoclinic phase content (%). The BFS test was performed in a mechanical testing machine (Instron 8874). Data (MPa) were analyzed by two-way ANOVA (grinding × airborne-particle abrasion and heat treatment × airborne-particle abrasion) and Tukey's post-hoc test (α = 0.05). The strength reliability was analyzed using the Weibull distribution. Grinding significantly decreased the BFS of the non-heat-treated groups (p < 0.01). Within the ground groups, the previous heat treatment did not influence the BFS (p > 0.05). Air abrasion only influenced the BFS of the ground/heat-treated groups (p < 0.01). For the non-heat-treated groups, the grinding did not decrease the Weibull modulus (m), but it did decrease the characteristic strength (σ0). For Rocatec Soft and 120-μm Al₂O₃particles + Rocatec Plus, the heat-treated groups presented lower m and higher σ0 than the ground/non-heat-treated groups. The independent variables did not seem to influence phase transformation. Air-abraded surfaces presented higher monoclinic zirconia content than the as-sintered and ground surfaces, which exhibited similar content. Even under irrigation, grinding compromised the Y-TZP ceramic strength. The sintering of the veneering porcelain rendered the previous heat treatment recommended by the manufacturer unnecessary. Airborneparticle abrasion influenced the strength of heat-treated zirconia.

Evaluation of roughness, wettability, and morphology of an yttria-stabilized tetragonal zirconia polycrystal ceramic after different airborne-particle abrasion protocols

Airborne-particle abrasion is an effective method of roughening a zirconia surface and promoting micromechanical interlocks with luting cements. However, the effect of different airborne-particle abrasion protocols on the micromechanical retention mechanism has been poorly investigated. The purpose of the study was to evaluate the effect of airborne-particle abrasion protocols on the surface roughness, wettability, and morphology of an yttria-stabilized tetragonal zirconia polycrystal ceramic. A total of 140 zirconia specimens (14 × 14 × 1.4 mm) were made from Lava and divided into 7 groups. Their surfaces were treated as follows (n = 20): as-sintered (control); airborne-particle abraded with 50-μm Al2O3 particles; 120-μm Al2O3 particles; 250-μm Al2O3 particles; 30-μm silica-coated Al2O3 particles (Rocatec Soft); 110-μm silica-coated Al2O3 particles (Rocatec Plus); and 120-μm Al2O3 particles followed by Rocatec Plus. The surface roughness (Ra) and wettability analyses were performed on the same specimens of each group. The test liquid used for the wettability analysis was the silane RelyX Ceramic Primer. Two additional specimens (6.0 × 6.0 × 1.0 mm) per group were prepared to evaluate the surface morphology with scanning electron microscopy. The roughness (Ra) data were analyzed by 1-way ANOVA and the Dunnett C test (α = .05), and the wettability data with 1-way ANOVA (α = .05). The Spearman correlation analysis was applied to test for a possible correlation between roughness and wettability. The control group (0.35 μm) exhibited the lowest mean roughness value (Ra), which was followed by Rocatec Soft (0.40 μm), 50-μm Al2O3 particles (0.52 μm), Rocatec Plus (0.69 μm), 120-μm Al2O3 particles (0.80 μm)/120-μm Al2O3 particles + Rocatec Plus (0.79 μm), and 250-μm Al2O3 particles (1.13 μm). No significant difference was found among the groups concerning wettability. No correlation (rs = -0.09; P = .27) was found between the 2 dependent variables. The scanning electron microscopy analysis indicated that the different airborne-particle abrasion protocols produced differences in the morphologic patterns. Although roughness and morphology of the zirconia surface varied according to the airborne-particle abrasion protocol, no close relationship was found between them. The roughness increase seemed to have followed the size of the particles.

Effect of particle size on the flexural strength and phase transformation of an airborne-particle abraded yttria-stabilized tetragonal zirconia polycrystal ceramic

Because airborne-particle abrasion is an efficient method of improving the bond at the zirconia-cement interface, understanding its effect on the strength of yttria-stabilized tetragonal zirconia polycrystal is important. The purpose of this study was to evaluate the effect of the particle size used for airborne-particle abrasion on the flexural strength and phase transformation of a commercially available yttria-stabilized tetragonal zirconia polycrystal ceramic. For both flexural strength (20.0× 4.0× 1.2 mm) (n=14) and phase transformation (14.0-mm diameter× 1.3-mm thickness) (n=4), the zirconia specimens were made from Lava, and their surfaces were treated in the following ways: as-sintered (control); with 50-μm aluminum oxide (Al2O3) particles; with 120-μm Al2O3 particles; with 250-μm Al2O3 particles; with 30-μm silica-modified Al2O3 particles (Cojet Sand); with 120-μm Al2O3 particles, followed by 110-μm silica-modified Al2O3 particles (Rocatec Plus); and with Rocatec Plus. The phase transformation (%) was assessed by x-ray diffraction analysis. The 3-point flexural strength test was conducted in artificial saliva at 37°C in a mechanical testing machine. The data were analyzed by 1-way ANOVA and the Tukey honestly significant difference post hoc test (α=.05). Except for the Cojet Sand group, which exhibited statistically similar flexural strength to that of the as-sintered group and for the group abraded with 250-μm Al2O3 particles, which presented the lowest strength, airborne-particle abrasion with the other particle sizes provided the highest values, with no significant difference among them. The as-sintered specimens presented no monoclinic phase. The groups abraded with smaller particles (30 μm and 50 μm) and those treated with the larger ones (110 μm and/or 120 μm particles and 250 μm) exhibited percentages of monoclinic phase that varied from 4% to 5% and from 8.7% to 10%. Except for abrasion with Cojet Sand, depending on the particle size, zirconia exhibited an increase or a decrease in its flexural strength. Airborne-particle abrasion promoted phase transformation (tetragonal to monoclinic), and the percentage of monoclinic phase varied according to the particle size.

Does rinsing following particle deposition methods have a negative effect on adhesion to titanium

This study evaluated whether air blasting or rinsing particle remnants with water would impair adhesion of resin composite to metal. Commercially pure titanium plates (1 mm x 25 mm x 50 mm) were wet polished down to 1200-grit silicone carbide abrasive and ultrasonically cleaned. They were then embedded in auto-polymerizing acrylic with the bonding surfaces exposed. Specimens were randomly assigned to one of the following particle deposition protocols (N = 60, n = 10 per group): group 1: particle deposition with aluminum trioxide (50 µm Al2O3) (AL) + air blasting + silane (ESPE-Sil); group 2: particle deposition with 30 µm SiO2 (CoJet) (CSC) + air blasting + silane; group 3: particle deposition with Rocatec Pre 110 µm Al2O3+Rocatec Plus 110 µm SiO2 (LSC) + air blasting + silane. In groups 4 (AL-W), 5 (CSC-W) and 6 (LSC-W), the same protocols were used, but instead of air blasting only, particle-deposited specimen surfaces were rinsed with water and air blasted. Adhesive resin (VisioBond) was applied and resin composite (Quadrant Posterior, Cavex) was bonded using polyethylene molds and photopolymerized. The specimens were then submitted to thermocycling (6000 cycles, 5°C-55°C, dwell time: 30 s, transfer time: 5 s). Pre-test failures during thermocycling were assigned a value of 0 MPa. Failure modes were identified using an optical microscope. SEM images of particles were obtained. Bond strength data (MPa) were statistically analyzed using two-way ANOVA and Tukey's post-hoc tests (a = 0.05). Particle type significantly affected the bond results (p < 0.001). AL groups presented significantly lower results (air blasting: 4.3 ± 3.3, rinsing: 11.8 ± 6.5) compared to those of CSC (air blasting: 27.7 ± 6.6, rinsing: 30.4 ± 9.3) and LSC (air blasting: 31.4 ± 8.7, rinsing: 28.7 ± 7.0). AL groups presented 5 spontaneous debondings during thermocycling in the air-blasted group. Rinsing with water as opposed to air blasting only did not decrease the results with any of the particle types (p > 0.05). While AL groups showed exclusively adhesive failure between the resin composite and the substrate, the incidence of cohesive failures in the composite was more frequent in groups CSC and LSC after either air blasting or rinsing. SEM images of particles showed sharp morphology of the particles in AL compared to CSC and LSC. Rinsing and air blasting following particle deposition methods did not impair adhesion of resin composite to titanium. Particle deposition with silica particles provided better adhesion of resin composite to this substrate compared to the use of alumina particles.

Air–particle abrasion on zirconia ceramic using different protocols: Effects on biaxial flexural strength after cyclic loading, phase transformation and surface topography

This study evaluated the effect of different air–particle abrasion protocols on the biaxial flexural strength and structural stability of zirconia ceramics. Zirconia ceramic specimens (ISO 6872) (Lava, 3M ESPE) were obtained (N=336). The specimens (N=118, n=20 per group) were randomly assigned to one of the air-abrasion protocols: Gr1: Control (as-sintered); Gr2: 50 µm Al2O3 (2.5 bar); Gr3: 50 µm Al2O3 (3.5 bar); Gr4: 110 µm Al2O3(2.5 bar); Gr5: 110 µm Al2O3 (3.5 bar); Gr6: 30 µm SiO2 (2.5 bar) (CoJet); Gr7: 30 µm SiO2(3.5 bar); Gr8: 110 µm SiO2 (2.5 bar) (Rocatec Plus); and Gr9: 110 µm SiO2 (3.5 bar) (duration: 20 s, distance: 10 mm). While half of the specimens were tested immediately, the other half was subjected to cyclic loading in water (100,000 cycles; 50 N, 4 Hz, 37 °°C) prior to biaxial flexural strength test (ISO 6872). Phase transformation (t→m), relative amount of transformed monoclinic zirconia (FM), transformed zone depth (TZD) and surface roughness were measured. Particle type (p=0.2746), pressure (p=0.5084) and cyclic loading (p=0.1610) did not influence the flexural strength. Except for the air-abraded group with 110 µm Al2O3 at 3.5 bar, all air-abrasion protocols increased the biaxial flexural strength (MPa) (Controlnon-aged: 1030±153, Controlaged: 1138±138; Experimentalnon-aged: 1307±184–1554±124; Experimentalaged: 1308±118–1451±135) in both non-aged and aged conditions, respectively. Surface roughness (Ra) was the highest with 110 µm Al2O3(0.84 µm. FM values ranged from 0% to 27.21%, higher value for the Rocatec Plus (110 µm SiO2) and 110 µm Al2O3 groups at 3.5 bar pressure. TZD ranged between 0 and 1.43 µm, with the highest values for Rocatec Plus and 110 µm Al2O3 groups at 3.5 bar pressure.

Effect of air-particle abrasion protocols on the biaxial flexural strength, surface characteristics and phase transformation of zirconia after cyclic loading

This study evaluated the effect of air-particle abrasion protocols on the biaxial flexural strength, surface characteristics and phase transformation of zirconia after cyclic loading. Disc-shaped zirconia specimens (Ø: 15mm, thickness: 1.2mm) (N=32) were submitted to one of the air-particle abrasion protocols (n=8 per group): (a) 50μm Al2O3 particles, (b) 110μm Al2O3 particles coated with silica (Rocatec Plus), (c) 30μm Al2O3 particles coated with silica (CoJet Sand) for 20s at 2.8bar pressure. Control group received no air-abrasion. All specimens were initially cyclic loaded (×20,000, 50N, 1Hz) in water at 37°C and then subjected to biaxial flexural strength testing where the conditioned surface was under tension. Zirconia surfaces were characterized and roughness was measured with 3D surface profilometer. Phase transformation from tetragonal to monoclinic was determined by Raman spectroscopy. The relative amount of transformed monoclinic zirconia (FM) and transformed zone depth (TZD) were measured using XRD. The data (MPa) were analyzed using ANOVA, Tukey's tests and Weibull modulus (m) were calculated for each group (95% CI). The biaxial flexural strength (MPa) of CoJet treated group (1266.3±158A) was not significantly different than that of Rocatec Plus group (1179±216.4A,B) but was significantly higher than the other groups (Control: 942.3±74.6C; 50μm Al2O3: 915.2±185.7B,C). Weibull modulus was higher for control (m=13.79) than those of other groups (m=4.95, m=5.64, m=9.13 for group a, b and c, respectively). Surface roughness (Ra) was the highest with 50μm Al2O3 (0.261μm) than those of other groups (0.15–0.195μm). After all air-abrasion protocols, FM increased (15.02%–19.25%) compared to control group (11.12%). TZD also showed increase after air-abrasion protocols (0.83–1.07μm) compared to control group (0.59μm). Air-abrasion protocols increased the roughness and monoclinic phase but in turn abrasion with 30μm Al2O3 particles coated with silica has increased the biaxial flexural strength of the tested zirconia.

Influence of surface conditioning on bonding to polyetheretherketon (PEEK)

ObjectiveThe purpose of the study was the evaluation of the bond strength of a provisional resin to a polyetheretherketon (PEEK) using different surface treatments and conditioning methods. MethodsPEEK disks were polished with 600grit rotating silicon carbide papers. Plexiglas tubes were filled and bonded with a provisional resin (Luxatemp Fluorescence) to the PEEK disks which were air-abraded either with 110μm alumina particles (Rocatec Pre) and conditioned with the primers Ecusit Composite Repair, Luxatemp Glaze & Bond or Clearfil Ceramic Primer or they were tribochemically silica-coated (Rocatec Plus) and silanated with Espe Sil or Clearfil Ceramic Primer. Air-abraded PEEK disks without priming served as control. Subgroups of 8 specimens each were stored in distilled water at 37°C either for 3 days without thermal cycling (TC) or for 150 days with additional 37,500 thermal cycles between 5 and 55°C (dwell time 30s). Following storage tensile bond strength (TBS) was tested at a crosshead speed of 2mm/min in a universal testing machine. Statistical analysis was conducted with Kruskal–Wallis test followed by Wilcoxon rank sum test adjusted by Bonferroni–Holm. ResultsAfter 3 days TBS ranged from 0 to 15.0MPa. After artificial aging over 150 days TBS ranged from 0 to 12.9MPa. Using air-abrasion and priming with Luxatemp Glaze & Bond resulted in significantly higher TBS than all other methods, which was also durable over time. ConclusionThe use of the methylmethacrylate containing primer Luxatemp Glaze & Bond after air-abrasion of PEEK surfaces can be recommended clinically as promising bonding method to PEEK.

Efficacy of air-abrasion technique and additional surface treatment at titanium/resin cement interface.

To evaluate the effect of surface treatments on the shear bond strength (SBS) of a resin cement to commercially pure titanium (CP Ti). Two hundred cast CP Ti disks were divided into 5 groups (n = 40), which were treated with one of the following air-abrasion techniques: (1) 50-µm Al2O3 particles; (2) 120-µm Al2O3 particles; (3) 250-µm Al2O3 particles; (4) 30-µm silica-modified Al2O3 particles (Cojet Sand); (5) 50-µm Al2O3 particles followed by 110-µm silica-modified Al2O3 particles (Rocatec Plus). For each air-abrasion technique, the following additional surface treatments were used (n = 10): (1) none; (2) adhesive Adper Single Bond 2; (3) silane RelyX Ceramic Primer; (4) silane plus adhesive. RelyX ARC resin cement was bonded to CP Ti surfaces. All specimens were thermocycled (5,000 cycles) before being tested in shear mode. Data (MPa) were analyzed using two-way ANOVA and Tukey's test (α = 0.05). Failure mode was determined with a stereomicroscope (20X). The results revealed that the air-abrasion technique (p < 0.001), additional surface treatment (p < 0.001) and their interaction were significant (p < 0.001). Except for the 50-µm Al2O3 + adhesive group, 250-µm Al2O3 particles promoted significantly higher SBS than 50-µm Al2O3 particles (p < 0.001), while Rocatec Plus provided bond strengths that were similar to or higher than those of Cojet Sand. Of the additional surface treatments, the adhesive provided the best results in combination with the 3 air-abrasion techniques (50-µm, 120-µm, and 250-µm Al2O3), whereas in the groups abraded with silica-modified Al2O3 particles (Cojet Sand and Rocatec Plus), the best results were obtained with additional silane. The two combinations that promoted the highest SBS were 250-µm Al2O3 + adhesive and Rocatec Plus + silane. All groups showed 100% adhesive failure. The selection of the best additional surface treatment varied according to the air-abrasion technique. Particle size was the decisive factor in determining the bond strength when micromechanical retention was the only bonding mechanism. When both mechanisms were present, in addition to particle size, the material applied as the additional surface treatment also contributed to determining the bond strength.

Surface Modification of In-Ceram Zirconia Ceramic by Nd:YAG Laser, Rocatec System, or Aluminum Oxide Sandblasting and Its Bond Strength to a Resin Cement

The purpose of this study was to evaluate the effect of different surface treatments on bond strength between In-Ceram Zirconia ceramic and Panavia Fluoro Cement. Although several surface treatments have been used on In-Ceram Zirconia, no study has been conducted to investigate the effect of the Nd:YAG laser. Nine In-Ceram Zirconia blocks (10 x 10 x 6 mm) received three different surface treatments (n = 3 per group): group 1-Al2O3 sandblasting + silane; group 2-Al2O3 sandblasting + Rocatec Plus + silane; and group 3-Al2O3 sandblasting + Nd:YAG laser + silane. Resin cement was applied and light-cured, followed by the application of composite resin. The blocks were sectioned to obtain square rods with a cross-sectional dimension of 1.0 mm2 (n = 12 per group). Microtensile bond strength (muTBS) was recorded using a universal testing machine at a cross-head speed of 0.5 mm/min and expressed in megapascals (MPa). All groups yielded statistically significantly different muTBS mean values: group 1 (11.81 +/- 3.12 MPa); group 2 (15.75 +/- 4.45 MPa); group 3 (18.70 +/- 5.14 MPa) (ANOVA and Tukey's test; alpha = 0.05). Nd:YAG laser irradiation is an effective surface treatment for bonding between In-Ceram Zirconia and Panavia Fluoro Cement.

Micro-Tensile Bond Strength Between a Resin Cement and an Aluminous Ceramic Treated with Nd:YAG Laser, Rocatec System, or Aluminum Oxide Sandblasting

The aim of this study was to evaluate the effect of different surface treatments on bond strength between In-Ceram Alumina (VITA) and Panavia Fluoro Cement (Kuraray), and to verify the association between bond strength values and the percentage of remaining cement on the ceramic surface. Although several conventional surface treatments have been used on aluminous ceramic, no study investigated the effect of the Nd:YAG laser. Nine In-Ceram Alumina blocks (10 x 10 x 6 mm) received three surface treatments: group 1, Al(2)O(3) sandblasting + silane; group 2, Al(2)O(3) sandblasting + Rocatec Plus + silane; and group 3, Al(2)O(3) sandblasting + Nd:YAG Laser + silane. Resin cement was applied and light cured, followed by the application of composite. Blocks were sectioned to obtain sticks with a cross-sectional area of 1.0 mm(2). Microtensile bond strength (microTBS) was recorded in a universal testing machine at a crosshead speed of 0.5 mm/min. Scanning electron microscopy images of the fractured areas were used to calculate the amount of remaining cement on the ceramic substrate. All treatments yielded statistically different microTBS values (MPa): group 1, 14.38(A); group 2, 20.09(B); and group 3, 23.21(C) (ANOVAand Tukey's test, alpha = 0.05). Pearson's correlation coefficient for microTBS x percentage of remaining cement was r = 0.92 (p < 0.05). The Nd:YAG laser was the most effective surface treatment, followed by Rocatec and Al(2)O(3) sandblasting. A strong positive association was found between bond strength values and percentage of remaining cement.

Weibull parameters of composite resin bond strengths to porcelain and noble alloy using the Rocatec system

Objective: The aim of the study was to determine the Weibull distribution parameters S 0 and m of the tensile bond strength of a composite resin sandwiched between a noble metal alloy and a feldspathic porcelain using the Rocatec system. Methods: Specimens were prepared either as Au-Pt-Pd alloy cylinders alone or as alloy cylinders and a feldspathic porcelain. Surface treatments included 110 μm Al 2O 3 sandblasting (Rocatec Pre), tribochemical silica coating (Rocatec Plus) and silane application (ESPE-Sil) prior to composite bonding. The tensile bond strengths of ceramic-resin-ceramic and metal-resin-metal specimens were determined before and after thermocycling at 5–60°C for 1000 cycles. Statistical analyses were conducted using two parameter Weibull distributions determined by the characteristic strength ( S 0) at the 63% probability of failure, the Weibull modulus ( m) and the 95% confidence intervals. Results: With respect to the control group (no Rocatec) (7.5 MPa), the Rocatec system significantly augmented the characteristic tensile bond strength S 0 of metal (17–18 MPa) and porcelain (20–28 MPa) groups. Thermocycling had no effect on the tensile bond strength of the metal samples and increased (not significant) the bond of the porcelain group. The Weibull modulus m for all groups ranged from 2.8 to 3.7. Significance: This study confirmed the efficacy of the Rocatec system for bonding composite resin to metal or ceramic substrates. However, the variability of the strength of the bond is shown in the low Weibull modulus values obtained. This reflect the difficulties in controlling flaw formation and warrants research for future improvement.