Titanium implant surface etching has proven an effective method to enhance cell attachment. Despite the frequent use of hydrofluoric (HF) acid, many questions remain unresolved, including the optimal ...etching time and its effect on surface and biological properties. The objective of this study was to investigate the effect of HF acid etching time on Ti topography, surface chemistry, wettability, and cell adhesion. These data are useful to design improved acid treatment and obtain an improved cell response. The surface topography, chemistry, dynamic wetting, and cell adhesiveness of polished Ti surfaces were evaluated after treatment with HF acid solution for 0, 2; 3, 5, 7, or 10 min, revealing a time-dependent effect of HF acid on their topography, chemistry, and wetting. Roughness and wetting increased with longer etching time except at 10 min, when roughness increased but wetness decreased. Skewness became negative after etching and kurtosis tended to 3 with longer etching time. Highest cell adhesion was achieved after 5-7 min of etching time. Wetting and cell adhesion were reduced on the highly rough surfaces obtained after 10-min etching time.
Texturization of surfaces is usually advantageous in biomaterial engineering. However, the details of the textured surfaces can be more determining on cell adhesion and proliferation, rather than ...their roughness degree. Titanium is extensively used as a dental implant material in the human body. In this paper, the effect of four surface treatments on commercially pure titanium has been evaluated. These treatments were polishing (pTi); hydrofluoric acid (HF) etching (eTi); Al
2O
3 blasting (bTi); Al
2O
3 blasting
+
HF etching (beTi). Roughness and fractal dimensions were obtained from atomic force microscopy. Wettability was measured using water sessile drops. Morphology and surface chemical composition were analyzed with scanning electron microscopy and energy dispersive X-ray (EDX). MG-63 cell cultures were performed at different times (180
min, 24
h, 48
h, 72
h). Lowest roughness was found in pTi samples followed by eTi, bTi and beTi samples. Etching generated surfaces with the highest fractal dimension and negative skewness. Young contact angles were similar except for pTi and bTi surfaces. Silicon and aluminum traces were found in pTi and bTi samples, respectively. Cell adhesion (≤24
h) was greater on bTi and beTi surfaces. After 48
h, cell proliferation, mediated by specific morphologies, was improved in eTi samples followed by beTi surfaces. For the same surface chemistry, cell growth was driven by topography features.
To characterize the surface topography of several dental implants for commercial use.
Dental implants analyzed were Certain (Biomet 3i), Tissue Level (Straumann), Interna (BTI), MG-InHex (MozoGrau), ...SPI (Alphabio) and Hikelt (Bioner). Surface topography was ascertained using a confocal microscope with white light. Roughness parameters obtained were: Ra, Rq, Rv, Rp, Rt, Rsk and Rku. The results were analysed using single-factor ANOVA and Student-Neuman-Keuls (p<0.05) tests.
Certain and Hikelt obtained the highest Ra and Rq scores, followed by Tissue Level. Interna and SPI obtained lower scores, and MG-InHex obtained the lowest score. Rv scores followed the same trend. Certain obtained the highest Rp score, followed by SPI and Hikelt, then Interna and Tissue Level. MG-InHex obtained the lowest scores. Certain obtained the highest Rt score, followed by Interna and Hikelt, then SPI and Tissue Level. The lowest scores were for MG-InHex. Rsk was negative (punctured surface) in the MG-InHex, SPI and Tissue Level systems, and positive (pointed surface) in the other systems. Rku was higher than 3 (Leptokurtic) in Tissue Level, Interna, MG-InHex and SPI, and lower than 3 (Platykurtic) in Certain and Hikelt.
The type of implant determines surface topography, and there are differences in the roughness parameters of the various makes of implants for clinical use.
•SAFs chemically stabilized the biomimetic precipitates and guarantees higher cell adhesion.•The apatite nucleation and growth on Ti surfaces depended on the underlying SAF.•Carboxyl-SAF promotes the ...formation of the thickest biomimetic coating, with lower fluid retention and cell adhesion.
To evaluate the effect of different Self-Assembled Films (SAFs) on the development of calcium-phosphate (Ca/P) biomimetic layers on commercially pure titanium (cpTi) and the final cell adhesion on these coatings.
A total of five different surfaces were evaluated. Alkyl phosphonate Self-Assembled Films (SAFs) with three different ending groups (methyl –CH3, carboxyl –COOH, and phosphonate –PO(OH)2) were used to cover ultra-polished cpTi surfaces. These functionalized surfaces were compared with a hydroxylated ultra-polished cpTi surface. A biomimetic Ca/P layer was deposited on each surface by precipitation. A control cpTi sample with no precipitates was introduced in the study. Topography (AFM), morphology (ESEM), chemistry (XPS, EDX), crystallography (XRD), wettability (dynamic contact angle), layer thickness (WLCM), percolation (fluid retention) and cell response analysis were used for surface characterization.
XRD showed the formation of hydroxyapatite (HA) in the four biomimetic coatings. The Ca/P ratios obtained by XPS in the four biomimetic coatings showed similar values (≈1.40) corresponding to amorphous hydroxyapatite. The water wettability of the biomimetic coatings was similar but the surface morphology was different. The thickest biomimetic coating with lower percolation threshold and greater cell adhesion was obtained on the carboxyl-terminated SAF. The biomimetic coatings improved the cell adhesion but it was further improved by the presence of underlying SAFs that bond the coating to cpTi surface.
The use of SAFs chemically stabilizes the biomimetic precipitates and guarantees higher cell adhesion than in absence of SAFs. The apatite nucleation and growth depended on the underlying SAF. Biomimetic coatings on hydroxylated surface increases cell adhesion but on SAFs functionalized surfaces achieve higher cell response. The SAFs with carboxyl ending group promoted the formation of thick and interconnected biomimetic coatings, with low fluid retention and a very significant cell response.
Background and Objective
The root surface topography exerts a major influence on clinical attachment and bacterial recolonization after root planing. In‐vitro topographic studies have yielded ...variable results, and clinical studies are necessary to compare root surface topography after planing with current ultrasonic devices and with traditional manual instrumentation. The aim of this study was to compare the topography of untreated single‐rooted teeth planed in vivo with a curette, a piezoelectric ultrasonic (PU) scraper or a vertically oscillating ultrasonic (VOU) scraper.
Material and Methods
In a randomized experimental trial of 19 patients, 44 single‐rooted teeth were randomly assigned to one of four groups for: no treatment; manual root planing with a curette; root planing with a PU scraper; or root planing with a VOU scraper. Post‐treatment, the teeth were extracted and their topography was analyzed in 124 observations with white‐light confocal microscopy, measuring the roughness parameters arithmetic average height, root‐mean‐square roughness, maximum height of peaks, maximum depth of valleys, absolute height, skewness and kurtosis.
Results
The roughness values arithmetic average height and root‐mean‐square roughness were similar after each treatment and lower than after no treatment ( p < 0.05). Absolute height was lower in the VOU group than in the untreated ( p = 0.0026) and PU (p = 0.045) groups. Surface morphology was similar after the three treatments and was less irregular than in the untreated group. Values for the remaining roughness parameters were similar among all treatment groups ( p > 0.05).
Conclusion
Both ultrasonic devices reduce the roughness, producing a similar topography to that observed after manual instrumentation with a curette, to which they appear to represent a valid alternative.
To evaluate in vitro the effect of cavity preparation with microburs and diamond-coated ultrasonic tips on the microleakage and marginal fit of six end-root filling materials. STUDY DESIGN. The ...following materials were assessed: amalgam (Amalcap), zinc oxide eugenol (IRM), glass ionomer (Vitrebond), compomer (Cavalite), mineral particle aggregate (MTA) and composite (Clearfil). Cavity preparation was performed with microburs or diamond ultrasonic tips in single-root teeth. The seal was evaluated in two experiments: a microleakage assay on the passage of dye to the interface; and a scanning electron microscopy study and analysis of epoxy resin replicas, measuring the size of gaps in the interface between filling material and cavity walls. Multifactorial ANOVA, multiple comparison test and Student 's t test were used for statistical analyses of the data, considering p <0.05 to be significant.
Clearfil and MTA achieved a hermetic seal. Leakage and interface gap size was greater with Cavalite than with Clearfil and MTA, followed by Vitrebond and IRM. The worst seal was obtained with Amalcap. The use of diamond-coated ultrasonic tips improved the seal and reduced the gap when using materials that did not hermetically seal the cavity (Amalcap, IRM, Cavalite, Vitrebond). The preparation technique did not affect materials that achieved a hermetic seal (Clearfil, MTA).
Clearfil and MTA obtained a hermetic seal due to their excellent marginal fit and are the most recommended materials for clinical use, taking account of their sealing capacity. Ultrasonic cavity preparation is preferable because it improves the seal and marginal fit of materials that do not achieve a hermetic seal of the cavity (Amalcap, IRM, Cavalite, Vitrebond).
To evaluate the shear bond strength of resin-based composite to dentin and enamel using three adhesive systems, two of them containing self-etchant primers. Wettability (contact angle measurements) ...of the primers of these three adhesive systems was also evaluated on superficial and deep dentin.
Contact angle measurements were performed on 30 caries-free extracted human third molars; specimens were sectioned parallel to the occlusal surface to expose superficial and deep dentin. Dentin was ground flat (600-grit SiC) under water to provide uniform surfaces. Contact angle measurements were performed to assess wettability using the Axisymmetric Drop Shape Analysis technique. In order to test the enamel bond strength, 30 extracted bovine incisors were embedded in acrylic resin and ground flat to 800-grit. The adhesives and composite resins were applied following the manufacturers' instructions. All the specimens were stored in water for 24 hrs at 37 degrees C and thermocycled (500x). Shear bond strengths were determined using a universal testing machine and the Watanabe device. For dentin bond strength testing, superficial and deep dentin was exposed in 60 third molars, by sectioning the occlusal surface immediately under the enamel-dentin junction or close to the pulp chamber. After grinding (500 grit SiC), the dentin surfaces were assigned to three groups: (1) Clearfil SE Bond (CSEB)/Clearfil AP-X resin composite. (2) Etch & Prime (E&P)/Degufill mineral resin composite. (3) Scotchbond Multi-Purpose Plus (SBMP)/Z100 resin composite.
One-way ANOVA and Student-Newman-Keuls multiple comparisons tests showed that no differences were found between contact angles on superficial and deep dentin. CSEB and E&P, without significant differences between them, had greater mean contact angle than SBMP. On enamel, Etch & Prime resulted in the lowest bond strength, but no significant differences existed with Scotchbond Multi-Purpose were found. On dentin, Clearfil SE Bond resulted in the significantly highest bond strength; no significant differences exist between Etch & Prime and Scotchbond Multi-Purpose.
Nonlinear piezoelectric materials are raised as a great replacement for devices that require low power consumption, high sensitivity, and accurate transduction, fitting with the demanding ...requirements of new technologies such as the Fifth-Generation of telecommunications (5G), the Internet of Things (IoT), and modern radio frequency (RF) applications. In this work, the state equations that correctly predict the nonlinear piezoelectric phenomena observed experimentally are presented. Furthermore, we developed a fast methodology to implement the state equations in the main FEM simulation software, allowing an easy design and characterization of this type of device, as the symmetry structures for high-order tensors are shown and explained. The operation regime of each high-order tensor is discussed and connected with the main nonlinear phenomena reported in the literature. Finally, to demonstrate our theoretical deductions, we used the experimental measurements, which presented the nonlinear effects, which were reproduced through simulations, obtaining maximum percent errors for the effective elasticity constants, relative effective permittivity, and resonance frequencies of 0.79%, 2.9%, and 0.3%, respectively, giving a proof of the potential of the nonlinear state equations presented for the unifying of all nonlinear phenomena observed in the piezoelectric devices.
This research evaluated the effect of pulp pressure on the micropermeability and sealing ability of etch & rinse and self-etching adhesives. Two etch & rinse adhesives (Prime&Bond NT and Admira Bond) ...and one self-etching adhesive (Xeno III) were used. Adhesive layer micropermeability was evaluated by using confocal laser scanning microscopy (CLSM). Eighteen molars were connected to a pulp pressure device and divided into two groups. One group was restored with pulp pressure and the other group without. Each group was divided into three subgroups according to the adhesive used. The adhesives were rhodamine-labeled and Class V cavities were restored. After restoration, all specimens were kept under pulp pressure conditions for 24 hours with fluorescein-labeled pulp fluid. The specimens were sectioned and the axial wall was observed under CLSM. A microleakage test was performed to evaluate the sealing. Thirty molars were divided into two groups. One group was prepared with a pulp pressure device and the other group without. Each group was divided into three subgroups as a function of the adhesive used. Class V cavities were restored and the specimens were immersed in fuchsin and sectioned. Microleakage and dentin penetration were recorded in the occlusal and gingival walls. A CLSM study showed that the etch & rinse adhesives had higher micropermeability compared to the self-etching adhesives and pulp pressure made all the adhesives more permeable. In the occlusal wall, the best sealing (hermetic) was obtained when etch & rinse adhesives were used. Xeno obtained the lowest occlusal sealing values. In the gingival wall, Xeno obtained the best sealing, followed by Admira and Prime&Bond. Pulp fluid decreased gingival wall sealing when etch & rinse adhesives were used but not when self-etching adhesive was used.
Dentin wetting by four adhesive systems Rosales-Leal, Juan I; Osorio, Raquel; Holgado-Terriza, Juan A ...
Dental materials,
11/2001, Letnik:
17, Številka:
6
Journal Article
Recenzirano
Objectives: To evaluate the dentin wetting by four adhesive systems and to relate the wetting properties with the adhesive efficiency.
Methods: Scotch Bond Multipurpose Plus (3M), Syntac ...Single-Component (Vivadent), One-Step (Bisco) and Heliobond (Vivadent) were used. The substrate was superficial and deep human dentin. Roughness and water contact angle were measured before and after acid etching. Dentin wetting by resins was studied by contact angle measurements as a function of time to evaluate the spreading time. The shear bond strength was evaluated following a single plane method, and the microleakage was evaluated in Class V cavities.
Results: Acid etching increased dentin roughness and wettability and no differences were found between acids tested. Dentin wetting and roughness was higher on deep dentin. Dentin wetting and shear bond strength of resins was similar except for Heliobond that displayed the lowest value. Microleakage was higher on the gingival wall, and the leaking was lowest for Scotch Bond Multipurpose Plus, and maximum for Heliobond. The spreading time exceeded 30
s with water-based and hydrophobic adhesives, and was lower with an acetone-based adhesive. Dentin depth had some influence on contact angle and shear bond strength: contact angles obtained with SBMP and One-Step were higher on superficial dentin, and shear bond strength for One-Step was higher on superficial dentin. Dentin wetting by resins could be correlated to shear bond strength and microleakage.
Significance: Dentin acid etching with different conditioners promotes similar roughness and wetting changes. On a similar substrate, the adhesion depends on the chemical and wetting characteristics of resins.
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