Roughness and wettability of aligner materials

2020 ◽  
Vol 47 (3) ◽  
pp. 223-231 ◽  
Author(s):  
Fabienne Suter ◽  
Spiros Zinelis ◽  
Raphael Patcas ◽  
Marc Schätzle ◽  
George Eliades ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Surface Energy ◽  
Work Of Adhesion ◽  
Critical Surface ◽  
Roughness Parameters ◽  
Critical Surface Tension ◽  
Energy Parameters ◽  
Intermediate Group ◽  
Significant Difference

Objective: The characterisation of surface roughness and energy of contemporary thermoplastic materials used in manufacturing of orthodontic aligners. Design: In vitro, laboratory study. Materials and methods: Four commercially available thermoplastic materials were selected (CA-medium/CAM, Essix-copopyester/COP, Duran/DUR and Erkodur/ERK). Five disks from each, as received, material were tested and subjected to: (1) reflected light microscopy; (2) optical profilometry for the estimation of Sa, Sz, Sq, Sdr, Sc, Sv surface roughness parameters (n = 5); and (3) contact angle measurements with a Zisman series of liquids for the estimation of critical surface tension (γC), total work of adhesion (WA), as well as the work of adhesion due to polar (WP) and dispersion (WD) components employing the Zisman method (n = 5/liquid). Thermoformed disks were prepared against a dental stone model and the roughness parameters were calculated again Statistical analysis was performed by one-way ANOVA/ Tukey multiple comparison test and t-test (a = 0.05). Results: Microscopic and profilometric analyses revealed a smooth surface texture in the as-received materials, but a very rough texture after thermoforming, with insignificant differences within each state. Significant differences in the as-received state were found in the surface energy parameters; CAM showed the lowest γC and the highest WA, WP, WD, whereas ERK with the highest γC demonstrated lower WA. COP and DUR were ranked in an intermediate group regarding γC, with a statistically significant difference in WA between them, mainly attributed to the lower WP of the former. Conclusion: Given the differences in surface energy parameters and the lack of roughness differences within the as received or thermoformed groups, it may be concluded that variations in the plaque retaining capacity are anticipated, determined by γC, WA and the WP, WD components.

Durability of Coatings Based on Sol Silicate Paint

2019 ◽  
Vol 394 ◽  
pp. 1-4
Author(s):  
Valentina Ivanovna Loganina ◽  
Yerkebulan Bisengalievich Mazhitov ◽  
Yuri Petrovich Skachkov
Keyword(s):  
Surface Tension ◽  
Surface Energy ◽  
Intermolecular Interaction ◽  
Frost Resistance ◽  
Hamaker Constant ◽  
Critical Surface ◽  
Freezing And Thawing ◽  
Critical Surface Tension

The results of the study provide information on the resistance of coatings based on the solof silicate paint in the process of freezing and thawing. It was found, that coatings based on sol silicatepaints are characterized by a higher resistance compared of silicate coatings. It is shown, that thecoatings withstood 50 cycles of alternate freezing and thawing. The surface energy of the coatingswas calculated using the critical surface tension of the fluid at the interface with the solid. Thedispersion contribution in the intermolecular interaction between the particles of the coatings wasestimated. The values of the surface tension of the coatings and the values of the dispersioncomponent of the surface energy of the coatings — the complex Hamaker constant — are calculated.It was revealed, that after testing a decrease in the values of the Hamaker constant is observed. It wasestablished, that after testing for frost resistance, the values of the Hamaker constant for coatingsbased on sol of silicate paint are higher compared to coatings based on silicate paint.

scholarly journals Enamel Surface Roughness after Lingual Bracket Debonding: An In Vitro Study

Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4196
Author(s):  
Martina Eichenberger ◽  
Anna Iliadi ◽  
Despina Koletsi ◽  
George Eliades ◽  
Carlalberta Verna ◽  
...  
Keyword(s):  
Surface Roughness ◽  
In Vitro Study ◽  
Rank Test ◽  
Roughness Parameters ◽  
Signed Rank ◽  
Fine Diamond ◽  
Before And After ◽  
Signed Rank Test ◽  
Lingual Brackets

The aim of the present study was to quantitatively assess changes in enamel roughness parameters before and after lingual bracket debonding. The lingual surface of 25 sound premolars extracted for orthodontic reasons was studied by 3D optical interferometric profilometry before and after debonding of lingual brackets following enamel finishing (with fine diamond) and polishing (with 12- and 20-fluted carbide burs). The roughness parameters tested were the amplitude parameters Sa and Sz, the hybrid parameter Sdr, and the functional parameters Sc and Sv. The parameter differences (after debonding-reference) were calculated, and statistical analysis was performed via a Wilcoxon signed-rank test. Statistically significantly higher values were observed in all the surface roughness parameters of enamel surfaces after finishing and polishing, with the mostly affected parameter being the Sdr. Under the conditions of the present study, the finishing and polishing instruments used after debonding of lingual noncustomized brackets created a surface texture rougher than the control in all the tested roughness parameters.

scholarly journals Predictability of Microbial Adhesion to Dental Materials by Roughness Parameters

Coatings ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 456 ◽  
Author(s):  
Andrea Schubert ◽  
Torsten Wassmann ◽  
Mareike Holtappels ◽  
Oliver Kurbad ◽  
Sebastian Krohn ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Titanium Alloy ◽  
Biofilm Formation ◽  
Dental Materials ◽  
Roughness Parameter ◽  
In Vitro Study ◽  
Mean Deviation ◽  
Roughness Parameters ◽  
Microbial Adhesion

Microbial adhesion to intraoral biomaterials is associated with surface roughness. For the prevention of oral pathologies, smooth surfaces with little biofilm formation are required. Ideally, appropriate roughness parameters make microbial adhesion predictable. Although a multitude of parameters are available, surface roughness is commonly described by the arithmetical mean roughness value (Ra). The present study investigates whether Ra is the most appropriate roughness parameter in terms of prediction for microbial adhesion to dental biomaterials. After four surface roughness modifications using standardized polishing protocols, zirconia, polymethylmethacrylate, polyetheretherketone, and titanium alloy specimens were characterized by Ra as well as 17 other parameters using confocal microscopy. Specimens of the tested materials were colonized by C. albicans or S. sanguinis for 2 h; the adhesion was measured via luminescence assays and correlated with the roughness parameters. The adhesion of C. albicans showed a tendency to increase with increasing the surface roughness—the adhesion of S. sanguinis showed no such tendency. Although Sa, that is, the arithmetical mean deviation of surface roughness, and Rdc, that is, the profile section height between two material ratios, showed higher correlations with the microbial adhesion than Ra, these differences were not significant. Within the limitations of this in-vitro study, we conclude that Ra is a sufficient roughness parameter in terms of prediction for initial microbial adhesion to dental biomaterials with polished surfaces.

scholarly journals Influence of Remineralizing Dentifrice in the Treatment of Erosive Enamel Lesions

2018 ◽  
Vol 20 (4) ◽  
pp. 238
Author(s):  
Júlia Bazaga Ferreira ◽  
Gabriella Rodovalho Paiva ◽  
Vinícius Rangel Geraldo-Martins ◽  
Juliana Jendiroba Faraoni ◽  
Regina Guenka Palma Dibb ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Laser Scanning ◽  
Tooth Enamel ◽  
In Vitro Study ◽  
Positive Control ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Significant Difference ◽  
Kolmogorov Smirnov

O objetivo deste trabalho in vitro foi avaliar a influência de diferentes agentes remineralizantes no tratamento de lesões erosivas em esmalte. Foram confeccionados espécimes de 4mmx4mm e 3 mm de espessura a partir da superfície vestibular de incisivos bovinos (n=10) e divididos aleatoriamente em 4 grupos. G1=aplicação do dentifrício remineralizante, G2= aplicação do agente potencializador remineralizante, G3= dentifrício remineralizante + agente potencializador remineralizante, G4=aplicação de verniz fluoretado (controle positivo), G5=nenhum tratamento (controle negativo). Os espécimes foram imersos em refrigerante durante um período de 10 dias. A rugosidade superficial foi analisada por meio de microscopia confocal de varredura a laser. Os dados foram analisados quanto à homogeneidade (Levene’s) e normalidade (Kolmogorov- Smirnov). Foram realizados testes paramétricos com análise de variância a dois critérios: fator tempo e fator tratamento, e pós-teste de Tukey para diferenciação das médias. Todos os testes estatísticos tiveram nível de significância de 5% (α=0,05). Os resultados obtidos mostraram diferenças estatisticamente significantes, demonstrando a redução da rugosidade da superfície do esmalte logo após o primeiro tratamento (G3) e para os demais grupos (G1, G2 e G4) somente após o segundo tratamento. Concluiu-se que a utilização de dentifrício composto por silicato de cálcio e fosfato de sódio influenciou na rugosidade do esmalte erodido do dente bovino.Palavras-chave: Dentifrícios. Erosão Dentária. Esmalte Dentário.Abstract The objective of this in vitro study was to evaluate the influence of different remineralizing agents in the treatment of enamel erosive lesions. Specimens of 4mmx4mm and 3mm thickness were made from the buccal surface of bovine incisors (n=10) and randomly divided into 4 groups. G1 = application of the remineralizing dentifrice, G2 = application of the remineralizing agent, G3 = remineralizing dentifrice + remineralizing agente, G4 = application of fluoride varnish (positive control), G5 = no treatment Specimens were immersed in refrigerant solution during a period of 10 days. The surface roughness was analyzed by means of confocal laser scanning microscopy. The data were analyzed for homogeneity (Levene's) and normality (Kolmogorov-Smirnov). Parametric tests with analysis of variance were performed on two criteria: time factor and treatment factor, and Tukey post-test for differentiation of means. All tests were statistically significant at 5% (α = 0.05). The results showed statistically significant difference, demonstrating the reduction of surface roughness after the first treatment (G3) and the other groups (G1, G2 and G4) only after the second treatment. It was concluded that the use of dentifrice composed of calcium silicate and sodium phosphate influenced the roughness of the eroded tooth enamel of the bovine tooth.Keywords: Dentifrices. Tooth Erosion. Tooth Enamel.

scholarly journals Antimicrobial and mechanical acrylic resin properties with silver particles obtained from Fusarium oxysporum

2018 ◽  
Vol 21 (1) ◽  
pp. 96 ◽  
Author(s):  
Tabata Prado Sato ◽  
Celio Ilidio Conjo ◽  
Rodnei Dennis Rossoni ◽  
Juliana Campos Junqueira ◽  
Renata Marques de Melo ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Fusarium Oxysporum ◽  
Biofilm Formation ◽  
Antimicrobial Agents ◽  
Acrylic Resin ◽  
Control Group ◽  
Significant Difference ◽  
Color Alteration ◽  
Cie Lab

<p><strong>Objective: </strong>This study evaluated the effects of the incorporation of silver nanoparticles (AgNPs) obtained from <em>Fusarium oxysporum</em> on heat-activated acrylic resin (HAAR) and their influence on resin’s surface roughness, hardness, color alteration and antimicrobial capacity against <em>Candida albicans</em>. <strong>Material and Methods:</strong> For this, 50 discs of HAAR (2x5 mm) were produced and divided into three groups, Control: HAAR; Ag1: HAAR plus 0.539 mg of AgNPs; and Ag2: HAAR plus 1.1 mg of AgNPs. Knopp hardness (HK), surface roughness (Ra and Rz) and color alteration according to the CIE Lab were measured. Specimens were then evaluated <em>in vitro</em> with regard to <em>C. albicans</em> biofilm formation through formed colony count (CFU/mL). Scanning Electron Microscopy (SEM) and Atomic force microscopy (AFM) analyses were performed. <strong>Results:<em> </em></strong>The addition of AgNPs of both concentrations changed Ra, Rz and HK significantly. There was statistically significant difference for L (p=0.00); a*(p=0.00) and b*(p=0.00) parameters. There were no differences between Ag1 and Ag2 biofilm formation, but the comparison of both with the control group presented a significant reduction (p=0.0091) on biofilm formation. SEM and AFM images showed no signs of NPs clustering. <strong>Conclusion:</strong> It can be concluded tha AgNPs incorporation in HAAR was effective in reducing <em>C. albicans</em> activity, with a slight change in color and hardness of the material, being effective therefore, in regions such as the dental prostheses palate, which have lesser aesthetic appeal.</p><p><strong>Keywords</strong></p><p>Acrylic resins; Silver; Antimicrobial agents.</p>

Influence of Polishing Systems on Surface Roughness of Composite Resins: Polishability of Composite Resins

2019 ◽  
Vol 44 (3) ◽  
pp. E122-E132 ◽  
Author(s):  
L St-Pierre ◽  
C Martel ◽  
H Crépeau ◽  
MA Vargas
Keyword(s):  
Surface Roughness ◽  
In Vitro Study ◽  
Threshold Value ◽  
Lower Surface ◽  
Composite Resins ◽  
Initial Surface ◽  
Final Surface ◽  
Significant Difference ◽  
One Step

SUMMARY Objectives: The objective of this in vitro study was to compare, with a threshold value of 200 nm, the surface roughness obtained when using 12 different polishing systems on four different composite resins (microfill, nanofill, and two nanohybrids). Methods and Materials: A total of 384 convex specimens were made using Durafill VS, Filtek Supreme Ultra, Grandio SO, and Venus Pearl. After sandblasting and finishing with a medium-grit finishing disc, initial surface roughness was measured using a surface roughness tester. Specimens were polished using 12 different polishing systems: Astropol, HiLuster Plus, D♦Fine, Diacomp, ET Illustra, Sof-Lex Wheels, Sof-Lex XT discs, Super-Snap, Enhance/Pogo, Optrapol, OneGloss and ComposiPro Brush (n=8). The final surface roughness was measured, and data were analyzed using two-way analysis of variance. Pairwise comparisons were made using protected Fisher least significant difference. Results: There were statistical differences in the final surface roughness between polishing systems and between composite resins (p&lt;0.05). The highest surface roughness was observed for all composite resins polished with OneGloss and ComposiPro Brush. Enhance/Pogo and Sof-Lex Wheels produced a mean surface roughness greater than the 200-nm threshold on Filtek Supreme Ultra, Grandio SO, and Venus Pearl. Data showed that there was an interaction between the composite resins and the polishing systems. Conclusions: A single polishing system does not perform equally with all composite resins. Except for Optrapol, multi-step polishing systems performed generally better than one-step systems. Excluding Enhance/Pogo, diamond-impregnated polishers led to lower surface roughness. Durafill VS, a microfill composite resin, may be polished more predictably with different polishers.

Effectiveness Evaluation Criteria of Using Fine Powders of Secondary Concrete as a Component of Composite Binder

2021 ◽  
Vol 1017 ◽  
pp. 163-171
Author(s):  
Tatiana Drozdyuk ◽  
Arkady Ayzenshtadt ◽  
Sergey Aksenov
Keyword(s):  
Free Surface ◽  
Surface Energy ◽  
Surface Activity ◽  
Free Surface Energy ◽  
Hydration Reaction ◽  
Critical Surface ◽  
Critical Surface Tension ◽  
Composite Binder ◽  
Fine Powders ◽  
Highly Dispersed

The paper considers the possibility of using energy criteria (surface activity, free surface energy) to quantify the efficiency of a highly dispersed system consisting of fine particles of secondary concrete as a component of composite binder of the hydration type of hardening. Using the G.A. Zisman method, the value of the critical surface tension was determined for secondary concrete fractions with different degrees of dispersion, which gives an idea of the free surface energy of a surface area unit. Based on the experimental data for determining the specific surface area and critical surface tension, the free surface energy and surface activity of the studied concrete powder were calculated, which can serve as criteria for quantitative energy characteristics of raw materials for the production of composite binders. Calorimetric studies related to measurements of the thermal effects of the hydration reaction of highly dispersed samples of secondary concrete have shown that this process is exothermic, the enthalpy of hydration of which is comparable to a similar parameter for cement. It was experimentally shown that fine powders of secondary concrete are effective as components of a composite binder, but they need to be pre-activated to optimal parameters, one of which is surface activity. In addition, the symbasis of changes in surface activity, the specific heat of the hydration reaction of highly dispersed concrete fractions and the compressive strength of fine-grained concrete samples made by using a composite binder containing a highly dispersed fraction of secondary concrete was established.

scholarly journals Influence of Toothbrush Abrasion and Surface Treatments on Roughness and Gloss of Polymer-Infiltrated Ceramics

Polymers ◽  
2021 ◽  
Vol 13 (21) ◽  
pp. 3694
Author(s):  
Nawaf Labban ◽  
Mohammad D. Al Al Amri ◽  
Sarah M Alnafaiy ◽  
Saleh M. Alhijji ◽  
Mohammad A. Alenizy ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Mean Value ◽  
Control Group ◽  
P Value ◽  
Distilled Water ◽  
Storage Medium ◽  
Significant Difference ◽  
Toothbrush Abrasion ◽  
Surface Gloss

The aim of this study was to compare the surface roughness and gloss of polymer-infiltrated ceramics after simulated in vitro toothbrushing in different storage mediums. Four polymer- infiltrated ceramics were evaluated, Lava ultimate (LU), Vita enamic (EN), Shofu (SH), and Crystal ultra (CU). The control group was a feldspathic ceramic, Vita Mark II (VM). One hundred and twenty specimens (12 × 14 × 2.5 mm) were prepared using a precision saw. For each material (n = 24), the specimens were allocated into two groups, polished and stained. The specimens of each group were stored (for 7 days) in either citric acid (0.2N) or distilled water. Data for surface gloss (ΔE*SCE-SCI) and roughness (Ra) were evaluated before (baseline) and after simulated toothbrushing. For toothbrushing simulation, a toothpaste slurry containing a toothpaste of 100 relative dentin abrasion (RDA) and 0.3 mL distilled water was used for 3650 cycles (7300 strokes) for each specimen. Data were analyzed using t-test and ANOVA. A p-value of ≤ to 0.05 was considered significant. The highest mean value of surface gloss was identified in CU (stained—water) (4.3 (0.47)) (ΔE*) and EN (stained—acid) (4.3 (1.00)) (ΔE*) specimens, whereas the lowest mean value was shown by SH (stained—acid) (2.04 (0.42)) (ΔE*) samples. The highest mean value of surface roughness was observed in SH (0.40 (0.99)) Ra (stained—acid) whereas the lowest in VM (0.13 (0.039)) Ra (polished—water). A significant difference (p < 0.05) was observed in surface roughness and gloss between the materials with simulated toothbrushing, except in VM and LU, respectively. Therefore, it can be concluded that simulated toothbrushing impacts on surface roughness and gloss, irrespective of the storage medium.

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