Mechanical and Surface Properties of Resilient Denture Liners Modified with Chitosan Salts

Chitosan (CS) and its derivatives show antibacterial and antifungal properties and could help treat and prevent denture stomatitis (DS). Mechanical and surface properties of resilient denture liners were evaluated when modified with CS salts. CS-hydrochloride (CS-HCl) and CS-glutamate (CS-G) were added to resilient denture liners Ufi Gel P and Coe-Soft at four different concentrations (0.1%, 0.2%, 0.4%, 1% w/w) from which specimens were produced, as well as a control group of each material with no added CS salt. Ten specimens per group (Ø 35 mm, height 6 mm) were manufactured. They were stored in distilled water at 37 °C for a total of 30 days (d). Shore A hardness (SHA) and surface roughness (Ra) were evaluated after 24 h (T1), 7 d (T2), 14 d (T3) and 30 d (T4). Kruskal–Wallis and U-test (Bonferroni-Holm adjusted) were used for statistical analysis (p ≤ 0.05). Ra increased significantly once CS salts were added. SHA increased significantly for some groups, but all specimens fulfilled requirements set by ISO 10139-2:2016. Modification with CS salts does not influence the mechanical properties of the modified resilient denture liners in a clinically relevant manner. Despite the increased roughness, the concept is suitable for further studies. Especially antimicrobial/antibiofilm studies are needed.

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Effect of thermomechanical densification of pine wood (Pinus sylvestris L.) on cutting forces and roughness during milling

Annals of WULS, Forestry and Wood Technology ◽

10.5604/01.3001.0015.2330 ◽

2021 ◽

Vol 113 ◽

pp. 36-42

Author(s):

Barbara Białowąs ◽

Karol Szymanowski

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Statistical Analysis ◽

Pinus Sylvestris ◽

Cutting Forces ◽

Physical And Mechanical Properties ◽

Milling Process ◽

Pine Wood ◽

Roughness Index ◽

Modified Wood

Effect of thermomechanical densification of pine wood (Pinus sylvestris L.) on cutting forces and roughness during milling. The paper presents the results of research concerning the assessment of machinability of pine wood thermomechanically compacted. The assessment was made on the basis of the cutting forces and surface roughness after the milling process. Selected properties of native and modified wood were examined. Based on the research, it was found that compacted wood is characterized by higher cutting forces during milling. The surface quality after milling was examined and the roughness index Ra values were determined. The research shows that the modified wood is characterized by a lower Ra value both along and across the grain. Statistical analysis showed that the modification had a statistically significant effect on the values of cutting forces and the physical and mechanical properties of the tested wood.

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Effects of Hydrothermal Treatment on the Phase Transformation, Surface Roughness, and Mechanical Properties of Monolithic Translucent Zirconia

Operative Dentistry ◽

10.2341/20-270-l ◽

2022 ◽

Author(s):

CY Zhang ◽

C Agingu ◽

H Yang ◽

H Cheng ◽

H Yu

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Phase Transformation ◽

Flexural Strength ◽

Hydrothermal Treatment ◽

Cross Sections ◽

Monoclinic Phase ◽

Control Group ◽

Hydrothermal Aging ◽

Characteristic Strength

SUMMARY Objectives: This study aimed to investigate the effects of hydrothermal treatment on four types of monolithic, translucent, yttria-stabilized, tetragonal zirconia polycrystals (Y-TZPs). Methods and Materials: Two commercially available Y-TZP brands—SuperfectZir High Translucency (Aidite Technology Co, China) and Katana HT (Kuraray Noritake Dental, Japan) were assessed. For each brand of Y-TZP, materials of four coloring types, including noncolored (NC), colored by staining (CS), precolored (PC), and multilayered (ML) specimens were investigated after hydrothermal aging in an autoclave at 134°C/0.2 MPa for 0 (control group), 5, 10, and 20 hours. The tetragonal-to-monoclinic phase transformation, surface roughness, flexural strength, and structural reliability (Weibull analysis) were measured and statistically analyzed (α=0.05). The subsurface microstructure was analyzed with scanning electron microscopy. Results: The group ML exhibited the lowest flexural strength and Weibull characteristic strength among the four coloring types (p<0.05). Slight increases in the monoclinic phase volume, flexural strength, and Weibull characteristic strength were observed after hydrothermal aging (pall<0.05). Regardless of coloring type, no significant effects of aging on the Weibull modulus or surface roughness were found for the tested materials. Compared with the Katana HT cross-sections, the SuperfectZir High Translucency cross-sections exhibited a similar but thicker transformation zone. Conclusions: The coloring procedure and material type were found to affect the mechanical properties and aging resistance of translucent monolithic Y-TZP ceramics. Regardless of the aging time, the surface roughness of the tested Y-TZP ceramics remained unchanged.

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Surface Roughness Changes in Denture Liners in Denture Stomatitis Patients

The International Journal of Prosthodontics ◽

10.11607/ijp.5108 ◽

2017 ◽

Vol 30 (6) ◽

pp. 561-564 ◽

Cited By ~ 4

Author(s):

Fernanda Valentini ◽

Murilo Luz ◽

Noéli Boscato ◽

Tatiana Pereira-Cenci

Keyword(s):

Surface Roughness ◽

Denture Stomatitis ◽

Denture Liners

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Evaluation of Some Mechanical Properties of a Maxillofacial Silicon Elastomer Reinforced with Polyester Powder

International Journal of Dentistry ◽

10.1155/2019/2948457 ◽

2019 ◽

Vol 2019 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Yagthan Mohammed Haider ◽

Zainab Salih Abdullah ◽

Ghasak H. Jani ◽

Norehan Mokhtar

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Tensile Strength ◽

Hardness Test ◽

Silicone Elastomer ◽

Control Group ◽

Silicone Elastomers ◽

Tear Strength ◽

To Come ◽

Post Hoc

Maxillofacial silicone elastomers are used to replace and reconstruct missing facial parts for patients with trauma or a certain disease. Although commonly favorable silicone elastomers are not ideal in properties, many studies have been carried out to improve their mechanical properties and to come out with ideal maxillofacial prosthetic materials, so as to render patients with the best maxillofacial prostheses. The aim of the current study is to evaluate the effect of addition of different concentrations of polyester powder on hardness, tear strength, surface roughness, and tensile strength of maxillofacial A-2186 RTV silicone elastomers. Polyester powder was added to the silicone elastomer in the concentrations of 1%, 3% and 5% by using an electronic digital balance, compared with the control group of 0% polyester filler. The shore A hardness test was done according to ASTM D 2240 standards. The tear test was done according to ASTM D624 type C standards. The tensile test was done according to ISO specification number 37:2011. The surface roughness test was performed according to ISO 7619-1 2010 specifications. The data collected were then analyzed using one-way analysis of variance (ANOVA) and post hoc and Fisher’s LSD tests. All three groups showed a highly significant increase in tear strength, tensile strength, hardness, and roughness, compared to the control group. Reinforcement of A-2186 Platinum RTV Silicone Elastomer with 5% polyester significantly improved the mechanical properties tested in this study.

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Evaluating the Influence of Fiber Composition and Structure of Knitting Fabrics on Total Hand Value (THV)

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.848.211 ◽

2016 ◽

Vol 848 ◽

pp. 211-215

Author(s):

Nareerut Jariyapunya ◽

Blažena Musilová ◽

Marie Koldinská

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Surface Properties ◽

Evaluation System ◽

Tensile Shear ◽

Knitted Fabrics ◽

Fiber Composition ◽

Composition And Structure ◽

Different Types ◽

Shear Bending

This paper presents analytical and experimental procedures to evaluate the influence of knitted fabrics on the total hand value (THV) for women’s winter thin dress. We examined and compared its mechanical properties, such as tensile, shear, bending, compression, surface roughness and friction properties, measured by the Kawabata Evaluation System for Fabrics (KES FB-Auto), of knitted fabrics with different fiber compositions and different types of knitted structures. The obtained results showed that the knitted structures have significantly influenced on the total hand value (THV) whereas the fiber compositions have shown a less effect on (THV). The existing results prove that the evaluation by KES FB-Auto system has been more beneficial for its basic of mechanical and surface properties. Moreover, the results could be analyzed for its new designing patterns for a refined, comfortable stretch fit.

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Antibiofilm and Protein-Repellent Polymethylmethacrylate Denture Base Acrylic Resin for Treatment of Denture Stomatitis

Materials ◽

10.3390/ma14051067 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1067

Author(s):

Salwa O. Bajunaid ◽

Bashayer H. Baras ◽

Abdulrahman A. Balhaddad ◽

Michael D. Weir ◽

Hockin H. K. Xu

Keyword(s):

Surface Roughness ◽

Acrylic Resin ◽

Control Group ◽

Solution Ph ◽

Biofilm Growth ◽

Denture Base ◽

Denture Stomatitis ◽

Colony Forming Unit ◽

Microbial Infections ◽

Unit Reduction

Candida albicans (C. albicans) biofilm is a common etiological factor in denture stomatitis. The purpose of this study was to investigate the effects of incorporating 2-methacryloyloxyethyl phosphorylcholine (MPC) as a protein repellent into a new high-impact denture acrylic (HIPA) resin on the surface roughness, solution pH, and C. albicans biofilm adhesion to the denture base. The new acrylic denture resin base was formulated by mixing MPC into HIPA resin at mass fractions of 1.5%, 3%, and 4.5%. Surface roughness was measured using a Mitutoyo surface roughness tester. C. albicans biofilm growth and viability were assessed via colony forming unit counts. The pH of the biofilm growth medium was measured using a digital pH meter. Adding MPC to the HIPA resin at percentages of 1.5% and 3% increased the roughness values significantly (p < 0.05), while adding 4.5% MPC resulted in no difference in roughness values to that of the control group (p > 0.05). All experimental groups demonstrated neutral pH values (pH ≅ 7) and were not significantly different from each other (p > 0.05). Incorporating 2-methacryloyloxyethyl phosphorylcholine at 4.5% resulted in a significant (≅1 log) colony-forming unit reduction compared with the control group with 0% MPC (p < 0.05). A fungal-retarding denture acrylic resin was developed through the incorporation of MPC for its protein-repelling properties. This newly developed denture acrylic material has the potential to prevent oral microbial infections, such as denture stomatitis.

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Effect of Different Dentifrices on the Surface Roughness of Acrylic Resins: An in vitro Study

The Journal of Contemporary Dental Practice ◽

10.5005/jp-journals-10024-2106 ◽

2017 ◽

Vol 18 (8) ◽

pp. 679-682

Author(s):

Nitin Gautam ◽

Aditi Sharma ◽

Unjum Bashir ◽

Sisir Rapolu ◽

Nallamilli Mamatha ◽

...

Keyword(s):

Surface Roughness ◽

In Vitro Study ◽

Positive Association ◽

Acrylic Resin ◽

Control Group ◽

Distilled Water ◽

Acrylic Resins ◽

Type Size ◽

Utmost Care

ABSTRACT Aim This study was undertaken to study the effect of three most commonly used dentifrices for denture cleaning and to find out any positive association between number of strokes by toothbrush and surface roughness of acrylic resin. Materials and methods About 40 acrylic rectangular blocks with high finish were polished until surface roughness was calculated as 0 µm. The materials tested were distilled water as a control group, Patanjali Dant Kanti, Colgate Total Cream, and Cleansodent as dentifrices. Stroking was done with dentifrices, and surface roughness readings were recorded at 1,000, 9,000, and 18,000 strokes. Results Patanjali Dant Kanti was found to have maximum abrasive potential followed by Colgate Total Cream, followed by Cleansodent and least by distilled water. Conclusion Surface roughness was found to be directly proportional to the type, size, and fineness of the abrasive component used; the professional denture cleanser (Cleansodent) has less abrasive potential than the regular toothpastes. Among those tested, the highest abrasive potential was found in Patanjali Dant Kanti and lowest by Cleansodent (denture cleanser). Clinical significance The patient as well as dentist should choose the dentifrice with utmost care noting the size and type of abrasives used. Washing the dentures normally with water without toothbrush daily and cleaning of dentures once in 10 to 15 days with a soft toothbrush and professional denture cleanser should be the line of maintenance of dentures. How to cite this article Gautam N, Sharma A, Bashir U, Rapolu S, Mamatha N, Sravani S. Effect of Different Dentifrices on the Surface Roughness of Acrylic Resins: An in vitro Study. J Contemp Dent Pract 2017;18(8):679-682.

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

Polymers ◽

10.3390/polym13213694 ◽

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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Effect of Natural and Industrial Juices on Surface Microhardness of Microhybrid and Nanohybrid Composites

Journal of Dentistry Indonesia ◽

10.14693/jdi.v28i2.1173 ◽

2021 ◽

Vol 28 (2) ◽

Author(s):

Razieh Meshki ◽

◽

Hanieh Hoseini ◽

Keyword(s):

Mechanical Properties ◽

Orange Juice ◽

Immersion Time ◽

Pomegranate Juice ◽

Repeated Measure ◽

Control Group ◽

Distilled Water ◽

Surface Microhardness ◽

Water Control ◽

Significant Difference

Numerous studies have been conducted on the effect of various beverages on the mechanical properties of toothcolored materials, however, little is known about the effects of these materials on composites, particularly newer types such as nanocomposites. Objectives: This study aimed to evaluate the surface microhardness of two types of composites, micro-hybrid (point 4) and nanohybrid (premise), after exposure to natural and industrial juices. Methods: In this experimental study, 90 disc-shaped specimens with a thickness of 2 mm and a diameter of 10 mm were taken from two composites, micro-hybrid Point4 (Kerr) and nanohybrid premise (kerr) (two groups of 45). Then, the specimens of each group were divided into 5 subgroups of 9 and were immersed for 7 days for 6 hours in 5 solutions of industrial orange juice, natural orange juice, industrial pomegranate juice, natural pomegranate juice, and distilled water (control group). Surface microhardness of specimens was measured by Vickers device at baseline, one day and one week after immersing. Data was measured by ANOVA, repeated measure test, and independent t-test. A significant level of α was 0.05. Results: The surface microhardness of two types of composites exposed to beverages was reduced significantly. However, no significant difference was found between natural and industrial juices in none of the composites. Conclusions: Natural and industrial juices can affect the surface microhardness of composites, which varies depending on the type of composite and the type of juice and immersion time.

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Effect of Sanding Processes on the Surface Properties of Modified Poplar Coated by Primer Compared with Mahogany

Coatings ◽

10.3390/coatings10090856 ◽

2020 ◽

Vol 10 (9) ◽

pp. 856 ◽

Cited By ~ 5

Author(s):

Qingqing Liu ◽

Di Gao ◽

Wei Xu

Keyword(s):

Surface Roughness ◽

Contact Angle ◽

Surface Treatment ◽

Surface Properties ◽

Equilibrium Contact Angle ◽

Density Parameter ◽

Distilled Water ◽

Poplar Wood ◽

Surface Pretreatment ◽

Average Spacing

The surface roughness, static and dynamic liquid wettability of modified poplar wood were measured by different surface treatment of brushing primer and sanding. With the increase of the number of grinding paper, the depth parameters Ra, Ry, Rz and Rp of surface roughness of modified poplar decreased, and the density parameter Sm (the average spacing of micro unevenness of contour) decreased at first and then increased. With the increase of number of the grinding paper, the contact angle of water and glycerol for modified poplar wood decreased at first and then increased. After the modified poplar wood was brushed with the primer and sanded with 240# sandpaper, the density parameter Sm was 0.307, the equilibrium contact angle of distilled water was 34.88, and the equilibrium contact angle of glycerin was 36.46, all of which were the lowest number. At this time, the surface roughness was improved, and the modified poplar has the good wettability that is greater than the mahogany wood wettability. Compared with mahogany, the rough depth parameters of the modified poplar are smaller to those of mahogany, but the Sm of modified poplar wood is greater than that of the mahogany. After the same surface pretreatment, the wetting speed of glycerol on the surface of mahogany is higher than that of the modified poplar.

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