Effect Of Different Surface Treatments Research Articles

Effect of surface treatments and bonding type on elemental composition and bond strength of dentin

The objective of this study was to explore the effect of different surface treatments and bonding types on elemental composition and bond strength of dentin. Under water cooling, 1.5 mm of tooth structure containing just dentin was cut from 39 extracted human molars. Dentin surfaces were untreated (control) or treated by erbium: yttrium aluminum garnet or femtosecond laser (n = 13, each). One sample from each group underwent scanning electron microscopy. Then, dentin surfaces were bonded by Clearfil SE Bond or Clearfil SE Protect (n = 6, each). Energy dispersive X-ray spectroscopy was performed both after surface treatment and bonding application. The dual-polymerized resin cement was applied to dentin surfaces with a special teflon mold (diameter:3 mm × height:3 mm). After polymerization of the resin cement, shear force was applied at the resin cement-dentin interface. Elemental composition value (weight%) of dentin after surface treatment was analyzed by one-way analysis of variance (ANOVA), and the difference value in pre and post-bonding elemental composition by two-way ANOVA. Paired t-tests were executed to compare the weight% values of each element before and after each bonding application. Bond strength was analyzed by two-way ANOVA. The post-hoc test was Tukey’s honest significant difference test. Both laser treatments increased the mineral content of dentin, compared to the controls (P<0.05). Application of bonding agents decreased the mineral content of dentin compared to the surface treated dentin. Bond strength was unaffected by either surface treatment or bonding type (P>0.05). For resin cementation, either surface treatment is suitable. After laser treatment, Clearfil SE Bond is recommended over Clearfil SE Protect.

Effect of different surface treatments on retention and fracture strength of zirconia crowns over Ti-base zirconia abutments

BackgroundLimited evidence suggested different outcomes of surface treatment methods on zirconia abutments and crowns. Therefore, we investigated the effect of grooving, hot etching, and airborne particle abrasion (APA) methods on zirconia crowns over Ti-base zirconia abutments retention and fracture strength. Materials and methodsIn this in vitro study, 110 zirconia crowns and abutments were divided into five groups, including APA for crown and grooved zirconia abutment (APACr-GrAb), APA for crown and hot etching zirconia abutment (APACr-HtAb), grooved modified zirconia crown and APA for zirconia abutments (GrCr-APAAb), hot etching modified zirconia crown and APA for zirconia abutments (HtCr-APAAb), and APA for both crown and zirconia abutments (control group). The retention and fracture strength were measured. Data were analyzed by ANOVA, Tukey, Kruskal-Wallis, and Mann-Whitney with Bonferroni correction tests (α=0.05). ResultsHot etching and grooving on the crown or abutment significantly resulted in higher retention (P<0.001). The fracture strength significantly differed among the five groups (P=0.041), with the highest fracture strength observed in the GrCr-APAAb group and the lowest for the APACr-GrAb group; however, no significant differences were found in pairwise comparisons between groups (P>0.05). By considering both fracture strength and retention, grooving, hot etching, and APA were confirmed for better crown and abutment function, respectively. ConclusionGrooving surface treatment was the best method due to its high fracture strength and retention, followed by hot etching due to its high retention compared to APA, which can be considered a suitable method for cementing zirconia crown on zirconia abutments.

Effect of Surface Treatments on Shear-bond Strength of Glass Ionomer Cements to Silver Diamine Fluoride-treated Simulated Carious Dentin.

This study investigated the effect of different surface treatments on the shear bond strength (SBS) and failure modes of self-cured (SC) and light-cured (LC) high-viscosity glass ionomer cements (HVGICs) to silver diamine fluoride (SDF)-treated simulated carious dentin (SCD). Extracted human premolars were sectioned and pH cycled for 10 days to simulate carious dentin. The demineralized specimens were treated with 38% SDF (Riva Star) for 2 minutes, washed, stored in deionized distilled water at 37°C for 2 weeks, and subjected to the following surface treatments (n=14): T1 - no treatment (control); T2 - 10 seconds polyacrylic acid (PAA); T3 - 5 seconds phosphoric acid (PPA); T4 - 5 seconds PPA plus universal adhesive (Zipbond); and T5 - 5 seconds PPA plus resin-modified GIC adhesive (Riva bond LC). SC (Riva Self-cure HV) and LC (Riva Light-cure HV) HVGICs were applied to the conditioned specimens and stored in artificial saliva at 37°C for 1 week. SBS and failure modes were subsequently determined. Statistical analyses were performed using Kruskal-Wallis/post-hoc Mann-Whitney U and Chi-square tests (α=0.05). The highest SBS was observed when SC and LC were restored with T2 and T5, respectively. Significant differences in SBS were as follows: SC - T2, T1 > T5, T3; LC - T5, T4, T3 > T2. SC generally exhibited adhesive failures, while LC presented both adhesive and mixed failures. The preferred method for preparing SDF-treated carious dentin before restoration application is PAA for SC and PPA plus RMGIC adhesive for LC HVGICs.

The effect of different surface treatments on composite repair

The effect of different surface treatments on composite repair

Effect of Silane-Containing Adhesives on Repair Bond Strength between Fresh and Aged Composite Materials-A Pilot Study.

This study investigated the effects of different surface treatments and a silane-containing adhesive on the repair bond strength between fresh and aged resin composites. A total of 140 composite specimens were prepared and aged for 24 h or 4 months. Each group was subdivided into seven subgroups (n = 10) depending on the surface treatment (no surface treatment (NT), sandblasting (SAND), or Sof-lex coarse disc (DISC)) in combination with the use of the silane-containing adhesive ScotchBond Universal Plus (SBU) or an adhesive without silane Prime&Bond Universal (P&B). The same composite was used for the repair as for the primary specimen. Specimens were dark stored in distilled water at 37 °C for 28 days. Shear bond strength was tested at a crosshead speed of 0.5 mm/min. The Kruskal-Wallis test with Bonferroni's post-hoc adjustment (α = 0.05) and the Mann-Whitney U-test were used for the statistical analysis. The results are shown as the median with the interquartile range. The highest bond strength (MPa) was achieved after 24 h in the DISC+P&B (20.39(16.85-28.83)). In the fresh 24 h group, the SAND+P&B (12.25(8.28-15.05)) and DISC+SBU (18.37(15.16-21.29)) were statistically similar. In the 4-month groups, both adhesives and surface treatments performed similarly. The NT, SAND, and DISC groups without adhesives had the lowest bond strength. In the repair of fresh or aged composite, the silane-containing adhesive SBU was not superior to the adhesive without the silane (P&B).

Effect of different surface treatments and adhesive cementation on the surface topography and flexural strength of translucent and ultra-translucent monolithic zirconia.

To evaluate the effect of different surface treatments and adhesive cementation on the miniflexural strength (MFS) of monolithic zirconia. Two-hundred and forty (240) sintered bars of translucent zirconia (ZT) and ultra-translucent zirconia (ZUT) were obtained (8 mm ×2 mm ×1mm). The bars were divided into 16 groups (n = 15) according to the factors "Zirconia" (ZT and ZUT), "Cementation" (Cem) and "surface treatment" (Ctrl:Control, Al:Aluminum oxide/Al2O3 50 µm, Si:Silica/SiO2 coated alumina particles oxide 30 µm, Gl:Glazing+hydrofluoric acid). Half of the bars received an adhesive layer application, followed by application of resin cement and light curing. The surface roughness was measured in non-cemented groups. All the bars were subjected to the MFS test (1.0mm/min; 100 kgf). Scanning electron microscopy was used for qualitative analyses. MFS data (MPa) and roughness (µm) were statistically evaluated by three-way and two-way ANOVA respectively and Tukey's test (5%). The surface treatment and the interaction were significant for roughness. Glazing promoted less roughness compared to silicatization. Regarding MFS, only the zirconia and surface treatment factors were significant. For ZT, the sandblasted groups had an increase in MFS and glazing reduced it. There was no difference between the groups without cementation for the ZUT; however, ZUT.Si/Cem, and ZUT.Al/Cem obtained superior MFS among the cemented groups. Sandblasting increases the flexural strength for ZT, while glaze application tends to reduce it. Applying resin cement increases the flexural strength of ZUT when associated with sandblasting. Sandblasting protocols promote greater surface roughness.

Does the internal surface treatment technique for enhanced bonding affect the color, transparency, and surface roughness of ultra-transparent zirconia?

To investigate the effects of different surface treatments and thicknesses on the color, transparency, and surface roughness of ultra-transparent zirconia. A total of 120 Katana ultra-translucent multi-layered zirconia specimens were divided into 12 groups according to the thickness (0.3, 0.5, and 0.7mm) and surface treatment (control, airborne particle abrasion [APA], lithium disilicate coating, and glaze on). Color difference (ΔE00) and relative translucency parameter (RTP00) were calculated using a digital spectrophotometer. The surface roughness (Ra, Rq, Sa, and Sq) was measured using a non-contact profile scanner. The surface morphologies and microstructures of the samples were observed using a tungsten filament scanning electron microscope. Statistical analyses were performed by one-way and two-way analysis of variance (ANOVA) followed by post hoc multiple comparisons and Pearson's correlation (α = 0.05). The results showed that the surface treatment, ceramic thickness, and their interactions had significant effects on ΔE00 and RTP00 (p < 0.001). The surface treatment significantly altered the micromorphology and increased the surface roughness of the ceramic samples. APA exhibited the lowest transparency, largest color difference, and highest surface roughness. Zirconia with 0.3mm and 0.7mm thicknesses showed strong negative correlations between Sa and RTP00. The three internal surface treatments significantly altered the surface roughness, color difference, and transparency of ultra-transparent zirconia. As the thickness increased, the influence of the inner surface treatment on the color difference and transparency of zirconia decreased. For new zirconia internal surface treatment technologies, in addition to considering the enhancement effect on the bonding properties, the potential effects on the color and translucency of high-transparency zirconia should also be considered. Appropriately increasing the thickness of zirconia restorations helps minimize the effect of surface treatment on the optical properties.

The effect of surface treatment and thermal aging on the bonding of clear aligner attachments to provisional resin-based material: shear bond strength analysis.

The aim of this study is to evaluate the effect of different surface treatments on the shear bond strength (SBS) of clear aligner attachments bonded to Bis-acryl provisional crowns. 120 cylindrical bisacrylic composite material (ProTemp type) specimens were prepared and divided into six groups (n = 20) based on surface treatment, control: (no treatment); super coarse grit diamond bur, carbide bur, alumina-blasting, non-thermal plasma treatment, and Er:YAG laser treatment. The features of treated surfaces were examined using scanning electron microscopy (SEM). A flowable composite resin (Transbond XT; 3M Unitek) was bonded to the specimens forming the attachment. Half of specimens were subjected to thermal cycling (5,000 cycles). SBS was measured before and after thermal cycling. Each specimen was loaded at the attachment/resin interface at a speed of 0.5 mm/min until failure. The nature of the failure was analyzed using the composite remnants index (CRI). Two-way ANOVA and Tukey HSD were used for data analysis α = 0.5. For CRI scores analysis, Kruskal-Wallis test and Dunn's multiple comparison were used as post-hoc test. SEM analysis showed that all surface treatments altered surface properties and increase surface bonding area. The specimens treated with plasma, Er:YAG laser, and alumina-blasting had higher SBS values before and after thermal cycling. In comparison to control plasma, Er:YAG laser, and alumina-blasting showed a significant increase in SBS (P < 0.001) while carbide and diamond bur groups showed no significant differences (P > 0.05). Thermal cycling significantly decreased the SBS of control, carbide bur, diamond bur, and Er:YAG laser while no significant effect of alumina-blasting and plasma group. Er:YAG laser and plasma groups significantly exhibited more dominance for scores 2 and score 3 and the absence of score 0. Alumina-blasting, Er:YAG laser, or non-thermal plasma surface treatments increased the shear bond strength between clear aligner attachments and resin-based restorations.

Effect of Different Surface Treatments as Methods of Improving the Mechanical Properties after Repairs of PMMA for Dentures.

Denture fractures are a common problem in dental practice, and their repair is considered a first option to restore their functional properties. However, the inter-material resistance may become compromised. Typically, the bond between these materials weakens. Therefore, various surface treatment methods may be considered to enhance their mechanical properties. Poly(methyl methacrylate) (PMMA) heat-polymerized resin (HPR) was used as the repaired material, cold-polymerized material (CPR) for the repairs, and different variants of alumina abrasive blasting (AB), methyl methacrylate (M), ethyl acetate (EA), methylene chloride (CH), and isopropyl alcohol (IA) treatments were applied. Finally, combined surface treatments were chosen and analyzed. Surface morphologies after treatments were observed by scanning electron microscopy and the flexural, shear, and impact strengths were tested. AB and chemical treatment with CH, M, and EA was used to improve all mechanical properties, and further improvement of the properties could be achieved by combining both types of treatments. Varied changes in surface morphologies were observed. Treatment with IA yielded less favorable results due to the low impact strength. The best results were achieved for the combination of AB and CH, but during the application of CH it was necessary to strictly control the exposure time.

Effect of different surface treatments on the repair bond strength between aged and new alkasite based restorative material.

This study investigates various surface treatment methods to assess shear bond strength between set Cention N (alkasite-based restorative material) and new alkasite based restorative material. Assessing different surface treatments provide insights in optimizing repair procedure that enables durability of the restoration, thus potentially benefitting clinical outcomes. A total of 48 alkasite based restorative material blocks, measuring 4 mm in depth and 4 mm in diameter, were prepared. The samples were randomly divided into 8 groups (n = 6) according to the surface treatment done. Group I: Surface preparation by bur; Group II: Surface treatment by laser; Group III: Application of 2-step etch and rinse adhesive (Adper Single Bond 2 adhesive),Group IV: Application of single step self-etch adhesive (Scotchbond Universal adhesive); Group V: Bur preparation followed by application of 2-step etch and rinse adhesive; Group VI: Bur preparation followed by application of single step self-etch adhesive; Group VII: Laser preparation followed by application of 2-step etch and rinse adhesive; and Group VIII: Laser preparation followed by application of single step self-etch adhesive. Post-surface preparation, all the specimens were restored with newly mixed alkasite material. Repair bond strength measurements were assessed with universal testing machine. Shapiro-Wilk and Levene's tests were used to check normality and Homogeneity of variance. ANOVA with post-hoc Games-Howell test and two-way ANOVA with post-hoc Bonferroni test was performed to evaluate the influence of surface preparation on the repair bond strength. Using a 2-step etch and rinse adhesive resulted in a higher repair bond strength (26.05±2.12) compared to other surface treatments. In contrast, roughening of the surface with burs led to lowest repair bond strength (17.06±3.29) (P=0.02). Application of 2-step etch and rinse adhesive to the existing alkasite based restorative material provides superior bonding with the newly added alkasite based restorative material.

Effect of Different Surface Treatments on the Bonding Strength of Three Different Post Biomaterials to a Resin-Based Luting Agent.

The aim of this study was to evaluate how different post-surface treatments affect the ability of luting cement to bond three different dental post materials to a resinous surface. The study analyzed a total of 108 posts categorized into three main groups: stainless steel, cast, and fiber posts. Next, the core group was divided into four subgroups (n = 9) according to the type of surface treatment applied: no surface treatment (NS), silanization (SZ), sandblasting (SB), and sandblasting plus silanization (SBSZ). Stainless steel posts exhibited the lowest bond strength, whereas fiber posts demonstrated the highest shear bond strength. When it comes to surface treatments, dental post-surfaces treated with sandblasting have been found to exhibit the highest bond strength, outperforming other methods. Comparing all methods of surface modification, sandblasting with 50 um Al2O3 particles demonstrated the strongest connection.

Effect of different surface treatments on repair bond strength of alkasite based restorative material

Background This study investigates various surface treatment methods to assess shear bond strength between set Cention N (alkasite-based restorative material) and fresh alkasite based restorative material. Assessing different surface treatments provide insights in optimizing repair procedure that enables durability of the restoration, thus potentially benefitting clinical outcomes. Methods A total of 48 alkasite based restorative material blocks, measuring 4 mm in depth and 8 mm in diameter, were prepared. The samples were randomly divided into 8 groups (n = 6) according to the surface treatment done. Group I: Surface preparation by bur; Group II: Surface treatment by laser; Group III: Application of 2-step etch and rinse adhesive (Adper Single Bond 2 adhesive),Group IV: Application of single step self-etch adhesive (Scotchbond Universal adhesive); Group V: Bur preparation followed by application of 2-step etch and rinse adhesive; Group VI: Bur preparation followed by application of single step self-etch adhesive; Group VII: Laser preparation followed by application of 2-step etch and rinse adhesive; and Group VIII: Laser preparation followed by application of single step self-etch adhesive. Post-surface preparation, all the specimens were restored with freshly mixed alkasite material. All samples were then subjected to repair bond strength measurements using a universal testing machine. ANOVA with post-hoc Games-Howell test and two-way ANOVA with post-hoc Bonferroni test was performed to evaluate the influence of surface preparation on the repair bond strength. Results Among the various surface treatments, use of a 2-step etch and rinse adhesive resulted in a higher repair bond strength compared to other surface treatments, whereas roughening of the surface using burs resulted in the lowest repair bond strength (P=0.02). Conclusion Application of 2-step etch and rinse adhesive to the existing alkasite based restorative material provides superior bonding with the freshly added alkasite based restorative material.

Repair of bulk-fill composite after different surface treatments

Purpose To evaluate the effect of different surface treatments on the shear bond strength of repaired aged bulk-fill composites. Materials and method 60 cylindrical specimens of bulk-fill composite (X-tra fil) were prepared and stored in artificial saliva for 3 months. They were divided randomly into 2 groups according to the different repair material (n = 30), (I) X-tra fil and (II) Grandio. Then, they were further divided into 3 subgroups according to surface treatments (n = 10), (A) no surface treatment (B) diamond bur abrasion, and (C) air abrasion. Futurabond U adhesive was applied to all specimens, and then the repair composites were added. All specimens were subjected to thermo-cycling. They were tested for shear bond strength using a universal testing machine. Fractured samples were examined under a stereomicroscope to determine the mode of failure. An additional 30 specimens were made to evaluate the surface roughness. Representative SEM micrographs for each surface treatment were taken to assess the surface topography. All data was collected, tabulated and statistically analyzed. Results Group I: The highest mean shear bond strength was recorded in the group (IB) followed by (IC) and then (IA). Group (IA) was significantly different from groups (IB) and (IC) (P &lt; 0.05). Group II: The highest mean shear bond strength was recorded in the group (IIB) followed by (IIC) then (IIA). Group (IIB) was significantly different from group (IIA) (P &lt; 0.05). All surface treatments demonstrated significantly greater shear bond strength than not having any physical surface treatment. Repairing X-tra fil can be performed by either X-tra fil or Grandio with no statistically significant difference. Most of the specimens in all groups showed mixed and cohesive failures. Diamond bur abrasion showed the highest surface roughness values followed by air abrasion then control group. Conclusion The shear bond strength of repaired bulk-fill composite with bur or air abrasion was comparable and greater than no surface treatment. There was no significant difference between the two repair materials used.

The effect of different surface treatments of 310S austenitic stainless steel on the corrosion behavior in supercritical water using slow positron methods

AbstractThe corrosion behavior of 310S austenitic stainless steel, subjected to different surface treatments machined (MA), sandblasting (SB), and polishing (PO), was exposed to a 550°C supercritical water (SCW) environment. The aged samples were analyzed using variable‐energy slow positron beam techniques. The obtained results revealed that the plastic deformation of the near‐surface region of the MA and SB samples was substantially recovered in the SCW conditions. At least two distinct oxide layers formed, and the oxidation process created a Fe/Cr depletion zone in the inner layer. Various surface treatments, however, led to different corrosion profiles. The depth profile of slow positron beam characterization suggests that significant residual stress and deformation zones on the surfaces of the sandblasted samples probably provided a diffusion path for the oxidation of the 310S. Only the SB samples exhibited a negative weight change after SCW exposure. At the same time, the SB samples showed the highest concentration of the positron traps in this region, which was explained by open‐volume defects associated with the microcracks introduced by sandblasting.

Effects of different surface treatments on surface topography and bond strength in the repair of fiber-reinforced dentin composite.

This study aimed to evaluate the effects of different surface treatments on the repair bond strength between a fiber-reinforced dentin composite and a posterior composite. Forty fiber-reinforced dentin composite resin blocks (4 mm × 4 mm × 4 mm) were separated into eight groups (n = 5) according to the surface preparation methods: (G1) negative control group, (G2) adhesive application, (G3) 50% dimethylsulfoxide (DMSO) application, (G4) 50% DMSO + adhesive application, (G5) 37% phosphoric acid etch + adhesive application, (G6) air abrasion + adhesive application, (G7) 37% phosphoric acid etch + 50% DMSO application + adhesive application, and (G8) air abrasion +50% DMSO application + adhesive application group. The composite surfaces were repaired in two layers with a posterior composite. Composite sticks were subjected to a micro tensile bond strength (μTBS) test. Fractured surfaces were evaluated using a stereomicroscope (×25). Short fiber-reinforced composite samples' surfaces were investigated by scanning electron microscope (SEM). Shapiro Wilk, one-way ANOVA, and Tukey HSD tests were used for statistical evaluation. The highest average (μTBS) values were observed in G8, whereas the lowest mean μTBS values were evident in the G1 group. Statistically significant μTBS values were found in all adhesive-applied groups when compared with the negative control group. Notably, the application of 50% DMSO without adhesive did not lead to a statistically significant increase in μTBS values. SEM images demonstrated that acid etching partially eliminated residues on the composite surface, while air abrasion had a detrimental effect on the integrity of fiber structures. In the repair of fiber-reinforced dentin composite with a posterior composite, adhesive application is an effective approach. The treatment of 50% DMSO without adhesive did not confer a statistically significant advantage, and the supplemental use of acid etch or air abrasion did not show an additional benefit compared to adhesive-only repairs. Adhesive application emerges as a potent and effective strategy for the repair of bur-roughened fiber-reinforced dentin composites. With its limitations, the study highlights the efficacy of adhesive-only repairs without the necessity for additional surface treatments.

Evaluation of Shear Bond Strength Between Zirconia Core and E. Maxpress with Veneering Porcelain by Different Surface Treatment

This in vitro study was conducted to evaluate the effect of different surface treatment (sandblasting with 50µm of Al2O3, etching with 5% of hydrofluoric acid and a combination of 50 µm of Al2O3and 5% of hydrofluoric acid) on the shear bond strength of veneering ceramic to zirconia and e.max press substructures .&#x0D; Eighty rectangular specimens (9mm length ×4mm width×4mm height) were fabricated and divided into two major groups(zirconia and e.max press), Forty specimens for each group. Then, each group was subdivided into four subgroups according to surface treatment (control group, sandblasting by 50µm of Al2O3,etching with 5% of hydrofluoric acid and a combination of 50 µm of Al2O3 and 5% of hydrofluoric acid),10samples for each group. then, they veneered with their corresponding veneering ceramic material (Vita VM9 ,E.max ceram) according to manufacturer's instructions.&#x0D; The results of shear bond strength test revealed that the highest mean was for a combination treatment groups followed by sandblasting groups then etching with acid groups and finally untreated groups. One-way ANOVA test showed there is highly significant difference among each subgroups. While, LSD test for zirconia subgroups showed, there is no-significant difference between acid etching (ZHF) and untreated (ZC) groups. Also, LSD test for e.max press subgroups showed there was non-significant difference between acid etching (EHF) and sandblasting (ESB) groups. student's t-test between two major groups showed, higher significant difference among untreated groups and sandblasting groups. While, there was significant difference among acid etching groups and a combination treatment groups for each major group.&#x0D; A combination of two surface treatments represented an effective method on the bond strength due to the cumulative effect of these treatments

Effect of ZrO2 paste, surface treatments, and storage on Weibull characteristics and resin bond strength to zirconia.

The objective is to evaluate the effect of different surface treatments and storage on the shear strength of ultratranslucent zirconia. 36 blocks of ultra-translucent zirconia were fabricated (7x7x2mm) and sintered. Then, divided into 12 groups according to the "surface treatment" (C -Primer; Al -Sandblasting with Al2O3 + Primer; Si -Silicate + Primer; Gl -Glaze + HF + Primer; Z -Zirlink; Zp -Zirlink + Primer) and "storage" factors (ST-with 150 days/37º and without). After surface treatment, five cylinders (Ø=2mm; h=2.0mm) of resin cement (n=15) were constructed in each ceramic block; at the end, the shear strength test was performed (1mm/min, 50Kgf), and analysis of surface failures. 60 additional samples (2x2x2mm) were made for extras analysis (surface roughness, MEV, and EDS). Bond strength and surface roughness data were statistically evaluated by ANOVA (2 factors/1 factor), Tukey test (5%), and Weibull analysis, respectively. ANOVA (2-way) revealed that all factors were statistically significant for bond strength. The silicatization groups (SiST: 30.47AMPa; Si: 29.21AMPa) showed the highest bond strength values, regardless of storage (Tukey's test). While the groups treated with Zirlink (ZST: 2.76FMPa; Z: 5.27EFMPa) showed the lowest values, just similar to the GlST group (5.14EFMPa). The Weibull modulus (m) showed a statistical difference between groups (p=0.000). ANOVA (1 factor) revealed that the "surface treatment" factor (p=0.0000) was statistically significant for surface roughness. Therefore, the application of Zirlink and Glaze on pre-sintered zirconia did not promote efficient adhesion of the ultratranslucent zirconia to the resin cement, even when associated with a primer containing MDP.

A comparative study of the effect of various surface treatments on the fracture behavior of aluminum adhesive joints under mode I loading

This study investigates the effect of different surface treatments on the fracture behavior of epoxy-aluminum joints under mode-I loading. Six surface treatments including degreasing, abrasion with varying grit sizes, alkaline etching, acid etching, a combination of alkaline and acid etching, and a combination of abrasion and acid etching were applied to aluminum surfaces before bonding. Surface morphology, roughness parameters, total surface free energy, contact angle, and elemental composition were analyzed. Results showed that the ultimate fracture load and fracture energy initially increased and then decreased with increasing surface roughness. The most effective treatments were found to be acidic etching in combination with alkaline etching and abrasion due to their synergetic effects. These treatments removed the natural oxide layer and created a porous oxide layer, enhancing surface roughness, increasing adhesive-substrate contact areas, and providing more sites for mechanical interlocking. Compared to the degreased specimens, significant improvements were observed, including a 40% and 31% increase in maximum fracture load, a 74% and 53% increase in initiation fracture energy, and a 65% and 47% increase in propagation fracture energy, respectively. Etching treatments demonstrated superior effects on the fracture behavior of aluminum adhesive joints compared to abrasion methods, leading to cohesive failure after etching treatments.

Effect of Different Surface Treatments on Repair Micro-Shear Bond Strength of An Injectable Composite

Effect of Different Surface Treatments on Repair Micro-Shear Bond Strength of An Injectable Composite

Assessment of a highly-filled flowable composite for the repair of indirect composites.

To compare the shear-bond-strength (SBS) of a highly-filled-flowable composite (HFFC) and a paste-type composite for indirect composite repair and to evaluate the effect of different surface treatments (ST), concerning the composite repair protocol. Eighty-four 5 × 5 × 2 mm cylindrical specimens were prepared using Gradia Plus and SR Nexco indirect composite materials. The samples were thermocycled 5,000 times. According to the ST, the samples were divided into three groups (control, bur, and air-abrasion). After ST, the sample subgroups were divided into two sub-groups according to the repair material: paste-type composite and HFFC (n = 7). Another 5,000 cycles of aging were performed. SBS values were measured with a universal testing machine (Shimadzu, Japan). Shapiro-Wilk, 3-way ANOVA, and Tukey HSD test were used to evaluate data (P < 0.05). ST was considered significant for SBS (P < 0.001). The mean values were (13.9 ± 5.7), (17.0 ± 6.4), (20.4 ± 4.9) MPa for the control, bur and phosphoric acid, and air-abrasion groups, respectively. The surface treatment and repair material interaction was considered significant for SBS (P = 0.044). The highest mean bond strength (24.5 ± 4.5 MPa) was observed for the interaction of SR Nexco, air-abrasion ST, and HFFC repair. Repairing with HFFC following air abrasion might enhance the SBS for indirect composite restorations.