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1.
J Esthet Restor Dent ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38963682

ABSTRACT

OBJECTIVE: To evaluate the effect of the deterioration of computer aided design/computer aided manufacturing (CAD/CAM) burs during zirconia milling, on surface roughness, contact angle, and fibroblast viability. MATERIALS AND METHODS: Ceramic blocks were milled and 75 ceramic disks (8 × 1.5 mm) made and allocated into three groups (n = 25): G1-brand new 2L and 1L burs, G2-2L bur at the end of lifetime and brand new 1L bur and G3-both burs at the end of their lifetimes. Roughness (Ra, Rq, and Rz) was evaluated using a 3D optical profilometer, the contact angle by the sessile drop method and the cell viability of the mouse NIH/3T3 fibroblast, using the Alamar Blue assay at intervals of 24, 48, and 72 h (ISO 10993-5). Data were analyzed by one-way ANOVA and Kruskal-Wallis tests (p ≤ 0.05). RESULTS: Roughness increased as the burs deteriorated and G3 (0.27 ± 0.04) presented a higher value for Ra (p < 0.001). The highest contact angle was observed in G3 (86.2 ± 2.66) when compared with G1 (63.7 ± 12.49) and G2 (75.3 ± 6.36) (p < 0.001). Alamar Blue indicated an increase in cell proliferation, with no significant differences among the groups at 24 and 72 h (p > 0.05). CONCLUSIONS: The deterioration of the burs increased the surface roughness and decreased the wettability, but did not interfere in cell viability and proliferation. CLINICAL SIGNIFICANCE: The use of custom zirconia abutments represents an effective strategy for single crowns restorations. Our findings suggest that these abutments can be efficiently milled using CAD/CAM burs within their recommended lifetime.

2.
Sci Rep ; 14(1): 15858, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38982227

ABSTRACT

Wear simulations of UHMWPE can economically and conveniently predict the performance of wear resistant bushings used for sealing or other reciprocating unidirectional sliding motion. In this study, pin on plate tribological experiments and microscopic analysis was done to obtained the wear profiles, wear volume and wear mechanism of UHMWPE against the counterface with different surface roughness of which Ra range is 0.03 ~ 2 µm. Meanwhile, the 3D wear simulation model of the pin on plate tribological experiments was established to discuss the adaptability of the energy and Archard wear model by analyzing the difference of wear profiles and wear volume between the experiment and simulation. The results indicate that with an increase in the counterface roughness, the wear simulation of UHMWPE estimated by the energy model were more accurate in reciprocating unidirectional sliding motion.

3.
Eur Oral Res ; 58(2): 76-82, 2024 May 05.
Article in English | MEDLINE | ID: mdl-39011171

ABSTRACT

Purpose: The purpose of the study was to evaluate and compare the effect of beverages, denture cleanser and chlorhexidine gluconate solution on surface roughness of flexible denture base material. Materials and methods: Fifty flexible denture base resin specimens measuring 50±1mm in diameter and 0.5±0.05 mm in thickness were fabricated. The specimens were divided into five groups each containing ten specimens. The specimens were immersed in distilled water (Control group A); hot coffee (Group B); cold beverage (Group C); sodium perborate containing denture cleanser (Group D) and 2% chlorhexidine gluconate solution (Group E). The specimens were immersed for 10 min daily in mentioned solutions for up to 60 days. Surface roughness (Ra) was evaluated on the 1st, 20th and 60th day with the help of atomic force microscope. The statistical analysis was done using two-way ANOVA and Tukey's Post hoc test. Results: The two- way ANOVA revealed that the average Ra values varied significantly depending on the type of solution used for immersion (p<0.001) and the duration of immersion (p<0.001). Variation in surface roughness with cold beverage was highest (p=0.001). On the 60th day the surface roughness of flexible denture base resin material was higher with cold beverage (0.184 µm) and denture cleanser (0.203 µm) than that of distilled water (0.052 µm) hot coffee (0.030 µm) and 2% chlorhexidine gluconate (0.068 µm). Conclusion: Exposure to cold beverage, which was acidic in nature and peroxide containing denture cleanser, produces much rougher surface in the thermoplastic polyamide flexible denture base resin specimens.

4.
Heliyon ; 10(11): e32162, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38947461

ABSTRACT

The primary purpose of this study was to evaluate the hydraulic coefficient of coarse aggregate grain size beds and hydraulic parameters under random and perpendicular bed configurations, as well as to explore the discharge coefficient for rectangular weirs. The research objectives were to compare flow resistance coefficients, evaluate the discharge coefficient for rectangular weirs, investigate the relationship between roughness coefficient and hydraulic parameters, and validate the theoretical hydraulic equation for the rectangular weir. This was achieved by analysing different bed configurations, bed slopes, and 20 and 30-mm bed materials. Sieve analysis was conducted on bed materials using American-standard sieves to determine their particle size distribution. The experiment was performed in a rectangular flume measuring 12 m in length, 0.31 m in width, and 0.45 m in depth. In a laboratory experiment, water was pumped into a flume using centrifugal pumps, and a rectangular weir was attached downstream for discharge measurement. The experiment investigated factors such as Manning roughness coefficient, bed material geometry, bed slope, and weir shapes. Approximately 1680 tests were conducted to analysed the impact of these factors on discharge and the coefficient of discharge. The average Manning's roughness coefficients for a grain size of 20 mm were 0.019 (with weir) and 0.019 (without weir) in a random bed configuration, and 0.028 (with weir) and 0.027 (without weir) in a perpendicular flow bed configuration. For a grain size of 30 mm, the coefficients were 0.023 (with weir) and 0.022 (without weir) in a random bed configuration, and 0.033 (with weir) and 0.026 (without weir) in a perpendicular flow bed configuration. The presence of a weir has affected Manning's roughness coefficients and discharge coefficients. With a weir, the roughness coefficients have generally been higher compared to without a weir, indicating increased roughness in the channel. The discharge coefficient for a rectangular weir with a grain size of 20 mm ranged from 0.39 to 0.84 (random bed) and 0.27 to 0.68 (perpendicular flow bed), while for a grain size of 30 mm it ranged from 0.31 to 0.81 (random bed) and 0.23 to 0.48 (perpendicular flow bed). The discharge coefficients have varied depending on the grain size and bed configuration, reflecting different flow efficiencies over the weir. Rough particles influenced flow and Manning's roughness coefficient value, then reduced discharge and velocity values. Under two bed configurations and slopes, beds with a grain size of 30 mm have higher roughness coefficients compared to those with a grain size of 20 mm. The models have shown that the roughness coefficient is inversely proportional to the discharge and directly proportional to the tailgate water levels. The coefficient of roughness and discharge coefficient are mainly influenced by the channel slopes, bed roughness, bed grain size, and bed configuration. A randomly configured bed with a 20 mm grain size gravel bed is preferred over a perpendicular bed configuration to handle high discharges. Using a 20 mm grain-size gravel bed in open-channel flow is more suitable than a 30 mm grain-size bed. Relying on the constant friction factor, Manning's n, is not recommended as it may result in design errors. These findings have the potential to improve hydraulic engineering design practices, enhancing the accuracy and efficiency of open-channel flow systems.

5.
J Mech Behav Biomed Mater ; 157: 106645, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38963999

ABSTRACT

In a technological context where, thanks to the additive manufacturing techniques, even sophisticated geometries as well as surfaces with specific micrometric features can be realized, we propose a mechano-regulation algorithm to determine the optimal microgeometric parameters of the surface of textured titanium devices for biomedical applications. A poroelastic finite element model was developed including a portion of bone, a portion of a textured titanium device and a layer of granulation tissue separating the bone from the device and occupying the space between them. The algorithm, implemented in the Matlab environment, determines the optimal values of the root mean square and the correlation length that the device surface must possess to maximize bone formation in the gap between the bone and the device. For low levels of compression load acting on the bone, the algorithm predicts low values of root mean square and high values of correlation length. Conversely, high levels of load require high values of root mean square and low values of correlation length. The optimal microgeometrical parameters were determined for various thickness values of the granulation tissue layer. Interestingly, the predictions of the proposed computational model are consistent with the experimental results reported in the literature. The proposed algorithm shows promise as a valuable tool for addressing the demands of precision medicine. In this approach, the device or prosthesis is no longer designed solely based on statistical averages but is tailored to each patient's unique anthropometric characteristics, as well as considerations related to their metabolism, sex, age, and more.

6.
Biofouling ; 40(7): 402-414, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38991845

ABSTRACT

Microbial fouling involves the physicochemical interactions between microorganisms and solid surfaces. An electromagnetic field (EMF) may change the diffusion rates of microbial cells and the electrical double layer around the cells and contacting surfaces. In the current study, polycardanol exhibiting antibiofouling activity was modified with ferromagnetic iron oxide (IO) to investigate the EMF effects on bacterial adhesion. When there was a flow of electrolyte that contained bacterial cells, flow-induced EMF was generated according to Faraday's principle. It was observed that the IO-ionic solution (IS)-modified surfaces, with an induced current of 44, 53, 66 nA, showed decreases in the adhesion of bacteria cells more than the unmodified (polycardanol) and IO-nanoparticles-modified ones. In addition to the EMF effects, the nano-scale uniform roughness of the modified surfaces appeared to play an important role in the reduction of cell adhesion. The results demonstrated that the IOIS-modified surface (3.2 × 10-6 mM IO) had the highest antibiofouling activity.


Subject(s)
Bacterial Adhesion , Biofouling , Electromagnetic Fields , Phenols , Surface Properties , Biofouling/prevention & control , Bacterial Adhesion/drug effects , Phenols/chemistry , Phenols/pharmacology , Ferric Compounds/chemistry , Biofilms/drug effects
7.
Materials (Basel) ; 17(13)2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38998404

ABSTRACT

This study investigates the effects of process parameters in the powder bed fusion-laser beam (PBF-LB) process on IN939 samples. The parameters examined include laser power (160, 180, and 200 W), laser scanning speed (400, 800, and 1200 mm/s), and hatch distance (50, 80, and 110 µm). The study focuses on how these parameters affect surface roughness, relative density, defect formation, and the microstructure of the samples. Surface roughness analysis revealed that the average surface roughness (Sa) values of the sample ranged from 4.6 µm to 9.5 µm, while the average height difference (Sz) varied from 78.7 µm to 176.7 µm. Furthermore, increasing the hatch distance from 50 µm to 110 µm while maintaining constant laser power and scanning speed led to a decrease in surface roughness. Relative density analysis indicated that the highest relative density was 99.35%, and the lowest was 93.56%. Additionally, the average porosity values were calculated, with the lowest being 0.06% and the highest reaching 9.18%. Although some samples had identical average porosity values, they differed in porosity/mm2 and average Feret size. Variations in relative density and average porosity were noted in samples with the same volumetric energy density (VED) due to different process parameters. High VED led to large, irregular pores in several samples. Microcracks, less than 50 µm in length, were present, indicating solidification cracks. The microstructural analysis of the XZ planes revealed arc-shaped melt pools, columnar elongated grains aligned with the build direction, and cellular structures with columnar dendrites. This study provides insights for optimizing PBF-LB process parameters to enhance the quality of IN939 components.

8.
Sci Rep ; 14(1): 16494, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39019987

ABSTRACT

TC21 alloy is a high-strength titanium alloy that has been gaining attention in various industries for its excellent combination of strength, toughness, and corrosion resistance. Given that this alloy is hard to cut material, therefore this study aims to optimize the process parameters of Turing this alloy under different conditions (i.e. as-received alloy, and heat-treated alloy). The L9 Taguchi approach-base orthogonal array is used to determine the optimum cutting parameters and the least number of experimental trials required. The achievement of this target, three different cutting parameters are used in the experimental work; each cutting parameter has three levels. The cutting speeds are chosen as 120, 100, and 80 m/min. The feed rates' values are 0.15, 0.1, and 0.05, mm/rev, and the depth of cut values are 0.6, 0.4, and 0.2 mm. After applying three steps of heat treatment (First step: is heating the sample to 920 °C for 1 h then decreasing to 820 °C also for 1 h, second step: cooling the sample to room temperature by water quenching (WQ), the third step: holding the sample at 600 °C for 4 h (Aging process)). The results revealed that the triple heat treatment led to the change in the microstructure from (α + ß) to (α + ß) with secondary α platelets (αs) formed in residual ß matrix leading to a decreased surface roughness by 56.25% and tool wear by 24.18%. The two most critical factors that affect the tool insert wear and surface roughness are the death of cut and cutting speed, which contribute 46.6% and 46.7% of the total, respectively. Feed rate, on the other hand, has the least importance, contributing 20.2% and 31.9% respectively.

9.
Rev Cient Odontol (Lima) ; 12(1): e185, 2024.
Article in Spanish | MEDLINE | ID: mdl-39015313

ABSTRACT

Objective: Compare the surface roughness of two composite resins after immersion in carbonated beverages. Materials and methods: 160 resin discs (6 x 2 mm) were divided into 8 groups (n=20 per group) according to type of resin (Filtek™ Z350 XT® and Palfique LX5®) and type of immersion in beverages (distilled water, Coca Cola®, Inca Kola® and Kola Escocesa®. The immersions were carried out under a structured cycle: 4 immersions a day for 5 days, intermediate storage in distilled water and overnight incubation for 8 h at 37°C. The measurements with the roughness meter were evaluated in three times: baseline, 7 and 14 days. The three-way Anova test was used at P<0.05. Results: Roughness showed differences only for the individual factors of time (P<0.000) and resin (P=0.000), and for the interaction time*drink (P=0.000) and resin*drink (P=0.003). Roughness was higher with Filtek Z350 XT® immersed with Inca Kola® (0.85 ± 0.37) than 14 days compared to other times (P=0.035) and with Palfique LX5 immersed in Coca Cola® at 7 days (1.61 ± 0.42) and in Inca Kola® at 14 days (1.66 ± 0.56) compared to distilled water (P<0,05). Conclusion: Surface roughness was affected by the type of resin, the type of soft drink and the immersion time. The roughness was greater with the Palfique LX5® nanohybrid resin, the Inca Kola® drink and after 14 days of immersion.

10.
Environ Monit Assess ; 196(8): 743, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39017951

ABSTRACT

This research bears significant implications for river management, flood forecasting, and ecosystem preservation in the Lower Narmada Basin. A more precise estimation of Manning's Roughness Coefficeint (n) will enhance the accuracy of hydraulic models and facilitate informed decision-making regarding flood risk management, water resource allocation, and environmental conservation efforts. Ultimately, this study aspires to contribute to the sustainable management of perennial river systems in India and beyond by offering a robust methodology for optimizing Manning's n tailored to the complex hydrological dynamics of the Lower Narmada Basin. Through a synthesis of empirical evidence and computational modelling, it seeks to empower stakeholders with actionable insights toward preserving and enhancing these invaluable natural resources. Using the new HEC-RAS v 6.0, a one-dimensional hydrodynamic model was developed to predict overbank discharge at different points along the basin. The study analyzes water levels, stream discharges, and river stage, optimizing Manning's n and required flood risk management. The model predicted a strong output agreement with R2, NSE, and RMSE for the 2020 event as 0.83, 0.81, and 0.36, respectively, with an optimum Manning's n of 0.03. The lower Narmada Basin part near the coastal zone (validation point) appears inundated frequently. The paper aims to provide insights into optimizing Manning's coefficient, which can ultimately lead to better water flow predictions and more efficient water management in the region.


Subject(s)
Environmental Monitoring , Floods , Hydrodynamics , Rivers , Rivers/chemistry , India , Environmental Monitoring/methods , Models, Theoretical , Hydrology , Conservation of Natural Resources/methods , Ecosystem , Water Movements
11.
BMC Oral Health ; 24(1): 765, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38970080

ABSTRACT

OBJECTIVE: To determine the effects of conventional cigarette smoking (CS) and recent heated tobacco products (HTPs) on the surface roughness and color stability of different indirect restorative materials. MATERIALS AND METHODS: One hundred disc-shaped samples were constructed of three different restorative CAD/CAM materials: lithium disilicate glass-ceramic (IPS e.max CAD; Ivoclar Vivadent, Liechtenstein), zirconia (BruxZir® Zirconia, Glidewell, USA) and polyetheretherketone (BioHPP® bredent GmbH, Germany). Of the IPS e.max CAD and the Bruxzir samples, 20 samples were glazed, and 20 samples were polished, while the BioHPP samples were all polished according to the manufacturer's instructions. Fifty samples were subjected to conventional cigarette smoking (LM, Philip Morris International Inc., Egypt) (Groups: IPS e.max CAD_Glazed exposed to CS (LD_G_Cig), IPS e.max CAD_Polished exposed to CS (LD_P_Cig), Bruxzir_Glazed exposed to CS (Zr_G_Cig), Bruxzir _Polished exposed to CS (Zr_P_Cig) and BioHPP exposed to CS (PEEK_Cig) and fifty samples were exposed to heated tobacco product smoking (Heets, Russet selection, Philip Morris International Inc., Italy) (Groups: IPS e.max CAD_Glazed exposed to HTP (LD_G_HTP), IPS e.max CAD_Polished exposed to HTP (LD_P_HTP), Bruxzir_Glazed exposed to HTP (Zr_G_HTP), Bruxzir CAD_Polished exposed to HTP (Zr_P_HTP) and BioHPP exposed to HTP (PEEK_HTP).. Six hundred cigarettes/heets representing 30 days of medium smoking behavior (20 cigarettes/day) were used. Before and after exposure to smoke, the surface roughness of all the samples was measured using JITAI8101 surface roughness tester (Beijing Jitai Tech Detection Device Co., Ltd, China, and the color parameters were assessed using VITA Easyshade Advance 4.01 (VITA shade, VITA made, VITA). The data were analyzed using One-way ANOVA, paired sample t-test and independent sample t-test. The significance level was set at α < 0.05. The surface topography was evaluated by scanning electron microscopy (SEM) and analyzed using energy-dispersive X-ray (EDX) spectroscopy to determine changes in the surface chemical composition. RESULTS: Both types of smoking caused significant increases in the surface roughness of all the samples. There was a significant difference in color change between CS and HTP for all materials with different surface finish (P < 0.01) and zirconia had the greatest effect on color change (P < 0.001). In contrast, polyetheretherketone (PEEK) "BioHPP" had the least effect (P < 0.001). CONCLUSION: Exposure to different types of smoking induce changes in the surface topography and color of different esthetic restorative materials. Compared with HTP, conventional cigarette smoke has a greater effect on the surface roughness and color stability of esthetic restorative materials. The glazed surfaces showed less change in surface topography than did the polished surfaces. Zirconia showed better color stability when compared to polyetheretherketone (PEEK).


Subject(s)
Ceramics , Cigarette Smoking , Computer-Aided Design , Dental Materials , Dental Porcelain , Ketones , Polyethylene Glycols , Polymers , Surface Properties , Tobacco Products , Zirconium , Polyethylene Glycols/chemistry , Zirconium/chemistry , Tobacco Products/adverse effects , Ceramics/chemistry , Ketones/chemistry , Dental Porcelain/chemistry , Cigarette Smoking/adverse effects , Dental Materials/chemistry , Benzophenones , Materials Testing , Hot Temperature , Humans , Color , Dental Restoration, Permanent
12.
Sci Rep ; 14(1): 15439, 2024 07 04.
Article in English | MEDLINE | ID: mdl-38965301

ABSTRACT

Replacing the conventional endodontic irrigants with herbal agents could avoid complications associated with using sodium hypochlorite (NaOCl). Endodontic irrigants alter the surface roughness of the dentinal wall surface, which affects sealer mechanical retention. This study aimed to assess the effect of experimental herbal Moringa oleifera and orange peel extract irrigant on intraradicular dentin (IRD) surface roughness using quantitative 3D surface analysis by scanning electron microscopy (SEM) regarding the smear layer assessment. Sixty human root sections were divided into four groups (n = 15): NaOCl combined with 17% ethylenediaminetetraacetic acid (EDTA); negative control (saline); moringa extract (MO); and orange oil (OO). SEM images were assessed quantitatively for surface roughness (Ra) in the coronal, middle, and apical IRD. The data were analysed by Kruskal-Wallis, Friedman, and Dunn's tests. All groups showed statistically significant differences (P = 0.007). MO exhibited significantly greater Ra values at the coronal, middle, and apical root levels than OO (P = 0.007, 0.009, and 0.046, respectively). There was no significant change in Ra values at various root levels within each group at P = 0.091, 0.819, 0.819, and 0.549 for the EDTA, saline, MO, and OO groups. Considerable (IRD) surface roughness analysis makes Moringa extract a promising herbal endodontic irrigant alternative to the NaOCl plus EDTA regimen.


Subject(s)
Dentin , Microscopy, Electron, Scanning , Plant Extracts , Root Canal Irrigants , Sodium Hypochlorite , Surface Properties , Humans , Root Canal Irrigants/pharmacology , Dentin/drug effects , Surface Properties/drug effects , Plant Extracts/pharmacology , Plant Extracts/chemistry , Sodium Hypochlorite/pharmacology , Sodium Hypochlorite/chemistry , Moringa oleifera/chemistry , Edetic Acid/pharmacology , Edetic Acid/chemistry , Citrus sinensis/chemistry , Tooth Root/drug effects
13.
J Dent ; 148: 105222, 2024 Jun 29.
Article in English | MEDLINE | ID: mdl-38950766

ABSTRACT

OBJECTIVES: To assess the impact of various organic and inorganic acids on the roughness, demineralization, and collagen secondary structures of human dentin and to compare these effects with those of traditional agents, specifically phosphoric acid (PA) and ethylenediaminetetraacetic acid (EDTA). METHODS: Coronal dentin discs (n = 10) were examined by optical profilometry (roughness) and ATR-FTIR before and after conditioning with 32 % PA, 3 % nitric acid (NA), 20 % citric acid (CA), 20 % phytic acid (IP6) or 17 % EDTA. Spectra data were processed to quantify dentin demineralization (DM%) and percentage area of amide I curve-fitted components of ß-turns, 310-helix, α-helix, random coils, ß-sheets, and collagen maturation index. Statistical analysis was performed by one-way ANOVA or Kruskal-Wallis for DM% and roughness parameters, and paired t-test/Wilcoxon test for amide I components at significance level set at α = 0.05. RESULTS: All treatments resulted in increased roughness parameters, with the most significant changes occurring primarily with PA, while EDTA exhibited the least changes. DM% was NA>PA>IP6>CA>EDTA in a descending order. Regarding amide I components, NA demonstrated a significant reduction in ß-turns, 310-helices, and α-helices and it increased ß-sheets and random coils. PA resulted in reduction in ß-turns and α-helices while it increased ß-sheets. CA and EDTA did not cause significant changes. The collagen maturation index significantly increased only after IP6 treatment. CONCLUSIONS: The effect on dentin roughness parameters, demineralization, and collagen secondary structures varied based on the type of dentin surface treatment. CLINICAL SIGNIFICANCE: Understanding the impact of acids on the intrinsic properties of dentin is clinically essential for gaining insights into how these effects influence adhesion to dentin, the long-term stability of resin-based restorations, and the success of remineralization therapies.

14.
Sci Rep ; 14(1): 15911, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38987571

ABSTRACT

In order to develop a method for the production of crack-free cladding layers, we combined surface texturing technology with laser cladding, establishing a multi-field coupled numerical simulation model. A separate investigation was conducted into the temperature, stress, and fluid fields in laser cladding processes with and without texturing, seeking optimal cladding parameters, and conducted experiments. The results of the numerical simulations indicate that pre-set texturing effectively reduces the temperature gradient during the cladding process, thereby making the thermal cycle curve smoother. The residual stresses in the X, Y, and Z directions are reduced by 34.84%, 3.94%, and 50.22%, respectively. The introduction of texturing reduces the internal flow velocity of the melt pool, preventing the occurrence of a double vortex effect. Experimental results show that the residual stresses in the X, Y, and Z directions of the predefined textured cladding layer are reduced by approximately 41%, 8%, and 47%, respectively, compared to the non-textured cladding layer. This effectively improves the surface roughness and internal grain size of the cladding layer, with no significant defects at the metallurgical bonding positions, providing a reference for future improvements in cladding layer quality.

15.
Cureus ; 16(7): e64500, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39007016

ABSTRACT

Objective This study aimed to investigate the longevity and effectiveness of bioactive glass (BAG)-based dental resin infiltrants. Materials and methods The three types of BAG - 45S5 bioglass (RIS), boron-substituted (RIB), and fluoride-substituted (RIF) - were incorporated with photoinitiated dimethacrylate monomers to create experimental resin infiltrants. ICON® (CN; DMG-America, Ridgefield Park, NJ) and pure resin (PR) were used as control groups in this study. Disc-shaped samples were prepared for the experimental and control groups. The samples were challenged with the pH cycle and immersed in the artificial saliva for 30 days. On Day 0 and Day 30, the pH cycle and artificial saliva immersion, Vicker's microhardness, surface roughness, and surface morphology were investigated. Results The RIF group's disc samples showed the highest Vicker's microhardness values (78.20 ±0.06) on Day 30 of artificial saliva immersion, whereas the CN group's values were the lowest (55.99 ±0.24). Following the pH cycling, the RIF displayed the highest hardness (64.15 ±1.89) whereas the CN group's values were the lowest (33.47 ±1.28). Regarding surface roughness, on Day 30, the RIB resin group exhibited the highest (1.14 ±0.001 µm). In contrast, the CN resin showed the lowest (1.07 ±0.06 µm) values, while immersed in the artificial saliva solution. In the same duration of time, in the pH cycling solution, PR showed the least (0.85 ±0.89 µm), while RIF showed the highest roughness value (0.94 ±0.54 µm). Morphological analysis revealed that following the artificial saliva immersion, the RIB, CN, and PR exhibited smoother surfaces compared to the RIS and RIF groups. However, when immersed in the pH cycling solution, RIB and RIF showed more resistance against acid attack. Conclusions Our results revealed that the experimental resin groups performed much better than the commercial resin infiltrants following artificial saliva and pH cycling challenges.

16.
Polymers (Basel) ; 16(13)2024 Jun 25.
Article in English | MEDLINE | ID: mdl-39000647

ABSTRACT

High-density polyethylene (HDPE) waste poses a significant environmental challenge due to its non-biodegradable nature and the vast quantities generated annually. However, conventional recycling methods are energy-intensive and often yield low-quality products. Herein, HDPE waste is upcycled into anti-aging, superhydrophobic thin films suitable for outdoor applications. A two-layer spin-casting method combined with heating-induced crosslinking is utilized to produce an exceptionally rough superhydrophobic surface, featuring a root mean square (RMS) roughness of 50 nm, an average crest height of 222 nm, an average trough depth of -264 nm, and a contact angle (CA) of 148°. To assess durability, weathering tests were conducted, revealing the films' susceptibility to degradation under harsh conditions. The films' resistance to environmental factors is improved by incorporating a UV absorber, maintaining their hydrophobic properties and mechanical strength. Our research demonstrates a sustainable method for upcycling waste into high-performance, weather-resistant, superhydrophobic films.

17.
Polymers (Basel) ; 16(13)2024 Jun 26.
Article in English | MEDLINE | ID: mdl-39000666

ABSTRACT

Oral film (OF) research has intensified due to the effortless administration and advantages related to absorption in systemic circulation. Chitosan is one of the polymers widely used in the production of OFs; however, studies evaluating the maintenance of the active principles' activity are incipient. Propolis has been widely used as an active compound due to its different actions. Printing techniques to incorporate propolis in OFs prove to be efficient. The objective of the present study is to develop and characterize oral films based on chitosan and propolis using printing techniques and to evaluate the main activities of the extract incorporated into the polymeric matrix. The OFs were characterized in relation to the structure using scanning and atomic force electron microscopy; the mechanical properties, disintegration time, wettability, and stability of antioxidant activity were evaluated. The ethanolic extract of green propolis (GPEE) concentration influenced the properties of the OFs. The stability (phenolic compounds and antioxidant activity) was reduced in the first 20 days, and after this period, it remained constant.

18.
Nanomaterials (Basel) ; 14(13)2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38998681

ABSTRACT

Surface roughness measurement is an integral part of the characterization of microtextured surfaces. Multiple established software packages offer the calculation of roughness parameters according to ISO 25178. However, these packages lack a specific set of features, which we hope to address in this work. Firstly, they often lack or have limited capabilities for automated and batch analysis, making it hard to integrate into other applications. Secondly, they are often proprietary and therefore restrict access to some potential users. Lastly, they lack some capabilities when it comes to the analysis of periodic microtextured surfaces. Namely, common parameters such as the peak-to-valley depth, spatial period and homogeneity cannot be calculated automatically. This work aims to address these challenges by introducing a novel Python library, Surfalize, which intends to fill in the gaps regarding this functionality. The functionality is described and the algorithms are validated against established software packages or manual measurements.

19.
BMC Oral Health ; 24(1): 789, 2024 Jul 13.
Article in English | MEDLINE | ID: mdl-39003474

ABSTRACT

BACKGROUND: Currently, the advantages of monochromatic universal composite resin restorative materials have increased their use in dentistry. Accordingly, the optical, surface and mechanical properties of these materials have become more important. This study aimed to evaluate the effect of detox solution on discoloration, surface roughness (SR), and microhardness of different monochromatic universal composite resins (Omnichroma [O], Zenchroma [Z], Vittra [V], and Charisma Diamond One [CDO]). Another aim of this study was to evaluate the monomer conversion degree (DC) of the materials. METHODS: A total of 80 specimens were prepared to evaluate the materials (n = 10). After the initial measurements, the specimens were immersed in a red detox solution for 21 days. Statistical data analysis was performed using one-way ANOVA and Tukey's multiple comparisons. RESULTS: The ∆E values of Z were highest on the 21st day. There was an increase in the SR values of the materials immersed in the detox solution. On the 21st day, top surface microhardness of O was lower than the other materials. There was no statistically significant difference at DC values among material groups. CONCLUSIONS: The use of detox solutions for a commercially recommended period of 21 days is suggested. However, this usage period can cause discoloration in restorative materials. Furthermore, especially in the initial one-week period, detox solution may have a negative impact on the microhardness of the materials. In light of all these data, we recommend the cautious use of detox solutions to prevent adverse effects on restorative materials.


Subject(s)
Color , Composite Resins , Hardness , Materials Testing , Surface Properties , Composite Resins/chemistry , Dental Materials/chemistry
20.
J Pharm Bioallied Sci ; 16(Suppl 2): S1566-S1573, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38882736

ABSTRACT

Aim of the Study: The aim of this in vitro study was to evaluate the effect of the resin infiltration technique and remineralization of induced enamel caries with fluoride solution on the color masking of white spot lesions and surface roughness. Materials and Methods: A total of 45 sound teeth were used in this study. All the teeth were sectioned along the long axes into two halves, lingual and buccal to get 90 specimens. All specimens were immersed in a demineralized solution for 7 days. The specimens were divided randomly into three equal groups (n = 30) according to the type of treatment; Group 1 (n = 30) was treated with fluoride varnish (Clinpro); Group 2 (n = 30) was treated by resin infiltration (Icon); and Group 3 (n = 30) was used as a control group with no treatment. The color and surface roughness were measured three times at baseline (T1), directly after induction of artificial white spot lesions (WSLs) (T2), and directly after application of the treatment options (T3). The colors were measured using a portable reflective spectrophotometer and the 3D surface roughness was measured using a Light Sectioning Vision System. Data were collected and statistically analyzed using T test and Mann-Whitney U test. The Results: Surface roughness was almost equal in the study groups with no statistically significant differences reported. Icon showed slightly higher color scores than that of ClinPro. Conclusions: The Icon produced favorable esthetic results compared to the fluoride therapy while no significant differences were reported regarding the surface roughness.

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