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1.
Braz. arch. biol. technol ; 63: e20190118, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132178

ABSTRACT

Abstract Aquaponics is a system that integrates aquaculture with plant production in which two species are benefited, and there is water saving. In this study was carried out with an aquaponic system to verify the interaction between the growth of the halophytes Batis maritime, Sarcocornia neei, and Sporobolus virginicus associated with white shrimp Litopenaeus vannamei rearing. We also investigated if there were different responses of physicochemical variables of the water in the experimental shrimp culture ponds integrated into the growth of plants and control ponds, without plants, throughout a 56-day period. The treatment experiment and control presented a statistically significant difference in total dissolved solids, salinity, total suspended solids, ammonia, orthophosphate, and nitrite. In the experimental treatment, with the presence of plants and recirculating water, a reduction of total suspended solids, ammonia and orthophosphate was observed. The rate of shrimp production was not significantly different between treatments, and the performance was similar to that of other studies. The biomass gain of the halophyte B. maritima was 876.6 grams in 0.5 m² and of S. neei was 48.8 grams in 0.16 m². All plants of the species S. virginicus died during the experiment.


Subject(s)
Animals , Water/chemistry , Chenopodiaceae/growth & development , Penaeidae/growth & development , Salt-Tolerant Plants/growth & development , Phosphates , Aquaculture , Hydroponics , Biomass , Chenopodiaceae/metabolism , Ammonia , Nitrites
2.
J. appl. oral sci ; 28: e20190039, 2020. tab, graf
Article in English | LILACS, BBO | ID: biblio-1090769

ABSTRACT

Abstract This study aimed to evaluate the physical properties and antifungal activities of polymethyl methacrylate (PMMA) acrylic resins after the incorporation of chlorhexidine diacetate salt (CDA). Methodology: First, acrylic resin specimens were fabricated with Vipi Cor® and DuraLay® resins with and without the incorporation of 0.5%, 1.0% or 2.0% CDA. The residual monomer and CDA release were measured at intervals ranging from 2 hours to 28 days using ultraviolet spectrometry combined with high-performance liquid chromatography. The antifungal activity against C. albicans was evaluated with the agar diffusion method. Fourier transform infrared spectroscopy was used to analyze the degree of resin conversion. Finally, the water sorption values of the resins were also measured. Results: The incorporated CDA concentration significantly changed the rate of CDA release (p<0.0001); however, the brand of the material appeared to have no significant influence on drug release. Subsequently, the inhibition zones were compared between the tested groups and within the same brand, and only the comparisons between the CDA 2% and CDA 1% groups and between the CDA 1% and CDA 0.5% groups failed to yield significant differences. Regarding the degrees of conversion, the differences were not significant and were lower only in the CDA 2% groups. Water sorption was significantly increased at the 1.0% and 2.0% concentrations. Conclusions: We concluded that the incorporation of CDA into PMMA-based resins enabled the inhibition of C. albicans growth rate, did not alter the degrees of conversion of the tested resins and did not change the release of residual monomers.


Subject(s)
Chlorhexidine/analogs & derivatives , Polymethyl Methacrylate/chemistry , Antifungal Agents/chemistry , Reference Values , Time Factors , Acrylic Resins/chemistry , Materials Testing , Candida albicans/drug effects , Water/chemistry , Chlorhexidine/pharmacology , Reproducibility of Results , Chromatography, High Pressure Liquid , Spectroscopy, Fourier Transform Infrared , Polymethyl Methacrylate/pharmacology , Antifungal Agents/pharmacology
3.
Int. j. high dilution res ; 19(1/2): 26-35, 2020.
Article in English | LILACS, HomeoIndex | ID: biblio-1146514

ABSTRACT

We have carried out systematic studies to investigate the effect on supercontinuumgeneration in water using 40 fs laser pulses when doped with Homeopathic medicines. We perform these studies using five series of medications with different levels of dilution (10-30 to 10-100000). We measure supercontinuum spectra that span from 400-1050nm. We monitor the area under the curve in the range 450-750 nm for each sample at a fixed incident laser energy. Our observations indicate that the yield of supercontinuum generation, in water containing Homeopathic medicine is significantly different from that obtained in water containing plain ethanol. The measurement for different dilutions shows up to 7 times standard deviation variation in the yield of supercontinuum generationEven though linear absorption in the UV-visible region does not show any significant difference for different Homeopathic medicines, the supercontinuum yield which depends on the effective nonlinear refractive index changes with different samples. (AU)


Subject(s)
Water/chemistry , High Potencies , Homeopathy
4.
J. oral res. (Impresa) ; 8(4): 337-342, nov. 5, 2019. tab
Article in English | LILACS | ID: biblio-1145363

ABSTRACT

Aims: Residual peroxide on the enamel surface and in the interprismatic spaces decreases the shear bond strength (SBS) of composite to bleached enamel. Evidence shows that 10% sodium ascorbate can efficiently neutralize the singlet oxygen generated by the bleaching agents. This study aimed to assess the effect of duration of application of sodium ascorbate on SBS of composite to bleached enamel. Materials and Methods: This in vitro experimental study was conducted on 30 sound human third molars, which were randomly divided into three groups (n=10). In group 1, the teeth were bleached for 45 minutes and were then subjected to immediate bonding and restoration with composite resin. In groups 2 and 3, the teeth were bleached, immersed in 10% sodium ascorbate solution for 5 (group 2) and 10 (group 3) minutes and were then bonded and restored with composite, and the SBS was then measured. Results: The highest SBS (14.02±8.6MPa) was noted in group 3 (immersion in 10% sodium ascorbate for 10 minutes before bonding). The lowest SBS was noted in group 1 (immediate bonding after bleaching) (p<0.05). The difference in SBS of groups 1 and 2 was not significant (p=0.4). Conclusion: Application of 10% sodium ascorbate for 10 minutes increases the SBS of composite to bleached enamel.


Objetivos: el peróxido residual en la superficie del esmalte dental y en los espacios interprismáticos disminuye la resistencia al cizallamiento (R AC) de la resina compuesta al esmalte dental blanqueado. La evidencia muestra que el 10% de ascorbato de sodio puede neutralizar eficientemente el oxígeno singlete generado por los agentes blanqueadores. Este estudio tuvo como objetivo evaluar el efecto de la duración de la aplicación de ascorbato de sodio en la R AC de la resina compuesta al esmalte dental blanqueado. Materiales y Metodos: Este estudio experimental in vitro se realizó en 30 terceros molares humanos sanos, que se dividieron aleatoriamente en tres grupos (n=10). En el grupo 1, los dientes se blanquearon durante 45 minutos y luego se sometieron a una unión y restauración inmediata con resina compuesta. En los grupos 2 y 3, los dientes se blanquearon, se sumergieron en una solución de ascorbato de sodio al 10% durante 5 (grupo 2) y 10 (grupo 3) minutos y luego se unieron y restauraron con resina compuesta; luego se midió la R AC. Resultados: La R AC más alta (14,02 ± 8,6 MPa) se observó en el grupo 3 (inmersión en ascorbato de sodio al 10% durante 10 minutos antes de la unión). El valor de R AC más bajo se observó en el grupo 1 (unión inmediata después del blanqueo) (p<0,05). La diferencia en R AC de los grupos 1 y 2 no fue significativa (p=0,40). Conclusión: la aplicación de ascorbato de sodio al 10% durante 10 minutos aumenta la R AC de la resina compuesta al esmalte dental blanqueado.


Subject(s)
Humans , Tooth Bleaching , Dental Bonding , Dentin-Bonding Agents/chemistry , Ascorbic Acid , In Vitro Techniques , Water/chemistry , Composite Resins/chemistry , Dental Enamel , Molar, Third , Antioxidants/chemistry
5.
J. appl. oral sci ; 27: e20180663, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-1040224

ABSTRACT

Abstract Objective: To investigate the use of polymethyl methacrylate (PMMA) electrospun fiber mats containing different amounts of polyethylene oxide (PEO) as a doxycycline delivery system and to test antibacterial activity against an oral pathogen. Methodology: PMMA powders or PEO (mol wt 200 Kd) (10,20,30% w/w/) were dissolved in N, N-dimethylformamide (DMF) to obtain a final polymer concentration of 15% in DMF (w/v). 2% Doxycycline monohydrate was added to the solutions and submitted to vortex mixing. The solution was transferred to a plastic syringe and fit into a nanofiber electrospinning unit. The parameters applied were: voltage at 17.2 kV; distance of 20 cm between the needle tip and the collector plate; target speed at 2 m/min; and transverse speed at 1cm/min. Syringe pump speed was 0.15 mm/min. The drug release analysis was performed by removing aliquots of the drug-containing solution (in PBS) at specific periods. Doxycycline release was quantified using RP-HPLC. Fiber mats from all groups had their antibacterial action tested against S. mutans based on inhibition halos formed around the specimens. The experiments were performed in triplicate. Gravimetric analysis at specific periods was performed to determine any polymer loss. Morphological characterization of the electrospun fibers was completed under an optical microscope followed by SEM analysis. Results: The addition of PEO to the PMMA fibers did not affect the appearance and diameter of fibers. However, increasing the %PEO caused higher doxycycline release in the first 24 h. Fibers containing 30% PEO showed statistically significant higher release when compared with the other groups. Doxycycline released from the fibers containing 20% or 30% of PEO showed effective against S. mutans. Conclusion: The incorporation of PEO at 20% and 30% into PMMA fiber mat resulted in effective drug release systems, with detected antibacterial activity against S. mutans.


Subject(s)
Polyethylene Glycols/pharmacokinetics , Doxycycline/pharmacokinetics , Polymethyl Methacrylate/pharmacokinetics , Nanofibers/chemistry , Anti-Bacterial Agents/pharmacokinetics , Polyethylene Glycols/chemistry , Streptococcus mutans/drug effects , Time Factors , Water/chemistry , Microscopy, Electron, Scanning , Reproducibility of Results , Analysis of Variance , Chromatography, High Pressure Liquid/methods , Doxycycline/chemistry , Polymethyl Methacrylate/chemistry , Immersion , Anti-Bacterial Agents/chemistry , Molecular Weight
6.
Neotrop. ichthyol ; 17(4): e190032, 2019. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1056797

ABSTRACT

This study aimed to assess the effects of low and high water hardness in interaction with different water pH in pacu (Piaractus mesopotamicus). Pacu juveniles were subjected to low (50 mg CaCO3 L-1 - LWH) or high water hardness (120 mg CaCO3 L-1 - HWH) at water pH of 5.5 (acidic), 7.5 (circumneutral) or 9.0 (alkaline) for 15 days. Gills and kidneys were collected (days 1, 5 and 15). Gill Na+/K+-ATPase (NKA) and vacuolar-type H+-ATPase (V-ATPase) activities were higher in alkaline pH with HWH on day 1. Gill and kidney NKA and V-ATPase activities were higher in acidic pH with LWH on day 15. Gill NKA activity of pacus under alkaline pH with LWH was higher than those exposed to HWH. Reduced antioxidant capacity in the gills and kidney and enhanced thiobarbituric acid reactive substances (TBARS) levels were demonstrated in fish exposed to acidic or alkaline pH, mainly with LWH. HWH increased glutathione-S-transferase (GST) activity and reduced TBARS levels in the gills and kidney. On day 15, GST activity was increased at acidic pH with LWH. In conclusion, circumneutral pH presents less oxidative stress and fewer variations in ATPases and HWH reduced deleterious effects in fish exposed to acidic or alkaline pH.(AU)


Este estudo objetivou analisar o efeito de baixa e alta dureza da água em interação com diferentes pH da água em pacu (Piaractus mesopotamicus). Juvenis de pacu foram submetidos a baixa (50 mg CaCO3 L-1 - BDA) ou alta dureza da água (120 mg CaCO3 L-1 - ADA) em pH da água de 5.5 ácido), 7.5 (circum-neutro) ou 9.0 (alcalino) por 15 dias. Foram coletados brânquias e rim (dias 1, 5 e 15). Atividade de Na+/K+-ATPase (NKA) e H+-ATPase do tipo vacuolar (V-ATPase) branquial foram maiores em pH alcalino com ADA no dia 1. Atividade de NKA e V-ATPase branquial e renal foram maiores em pH ácido com BDA no dia 15. Atividade de NKA branquial de pacus submetidos a pH alcalino com BDA foi maior que aqueles expostos para ADA. Em peixes expostos a pH ácido ou alcalino com BDA houve redução da capacidade antioxidante nas brânquias e rim e aumento dos níveis de "substâncias reativas ao ácido tiobarbitúrico" (TBARS). Em ADA aumentou a atividade da "glutationa-S-transferase" (GST) e reduziu níveis de TBARS nas brânquias e rim. No dia 15, a atividade da GST foi maior em pH ácido com BDA. Em conclusão, pH circum-neutro apresentou menor estresse oxidativo e poucas variações na atividade de ATPases e ADA reduziu efeitos deletérios em peixes expostos a pH ácido ou alcalino.(AU)


Subject(s)
Animals , Water/chemistry , Characiformes/anatomy & histology , Characiformes/physiology , Oxidative Stress , Hydrogen-Ion Concentration
7.
J. appl. oral sci ; 27: e20180230, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-984573

ABSTRACT

Abstract Objectives To study the fluoride uptake and release properties of glass carbomer dental cements and compare them with those of conventional and resin-modified glass ionomers. Materials and Methods Three materials were used, as follows: glass carbomer (Glass Fill), conventional glass ionomer (Chemfil Rock) and resin-modified glass ionomer (Fuji II LC). For all materials, specimens (sets of six) were matured at room temperature for time intervals of 10 minutes, 1 hour and 6 weeks, then exposed to either deionized water or sodium fluoride solution (1000 ppm in fluoride) for 24 hours. Following this, all specimens were placed in deionized water for additional 24 hours and fluoride release was measured. Results Storage in water led to increase in mass in all cases due to water uptake, with uptake varying with maturing time and material type. Storage in aqueous NaF led to variable results. Glass carbomer showed mass losses at all maturing times, whereas the conventional glass ionomer gained mass for some maturing times, and the resin-modified glass ionomer gained mass for all maturing times. All materials released fluoride into deionized water, with glass carbomer showing the highest release. For both types of glass ionomer, uptake of fluoride led to enhanced fluoride release into deionized water. In contrast, uptake by glass carbomer did not lead to increased fluoride release, although it was substantially higher than the uptake by both types of glass ionomer. Conclusions Glass carbomer resembles glass ionomer cements in its fluoride uptake behavior but differs when considering that its fluoride uptake does not lead to increased fluoride release.


Subject(s)
Apatites/chemistry , Resin Cements/chemistry , Fluorides/chemistry , Glass Ionomer Cements/chemistry , Reference Values , Resins, Synthetic/chemistry , Sodium Fluoride/chemistry , Time Factors , Materials Testing , Water/chemistry , Analysis of Variance , Aluminum Silicates/chemistry
8.
J. appl. oral sci ; 27: e20180093, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-975896

ABSTRACT

Abstract Surface changes in biological environments are critical for the evaluation of physical and biological activity of biomaterials. Objective: This study investigated surface alterations of calcium silicate-based cements after exposure to different environments. Material and Methods: Forty-eight cylindrical cavities were prepared on root surfaces. The cavities were filled using ProRoot MTA or Biodentine and assigned to four subgroups (n=6): dry, wet, acidic, and blood. Surface topographies were evaluated using an optical profilometer for 28 days, and the roughness of the material surfaces was quantified. Vertical dimensional change was measured by determining the height difference between the material surface and the flat tooth surface. Data were compared with a two-way repeated measures ANOVA and Bonferroni tests. Results: In dry condition, the surface roughness of MTA or Biodentine was constant up to 3 days (p>0.05) but decreased after 28 days (p<0.05). In dry condition, ProRoot MTA presented constant surface level through time, while Biodentine showed decreased surface level after 28 days. In wet condition, the roughness and the surface levels of both materials increased after 1 day (p<0.05). Neither the surface roughness nor the levels of the materials showed significant changes in acidic conditions (p>0.05). Both materials showed the highest roughness in blood conditions on the 1st day (p<0.05), while the surface roughness in blood decreased dramatically after 28 days. The roughness of Biodentine was higher in wet conditions up to 3 days compared with ProRoot MTA (p<0.05). Likewise, in blood condition, Biodentine showed higher roughness on the 28th day than ProRoot MTA (p<0.05). Conclusions: Dry, wet, and blood conditions had a time-dependent effect on the surface roughness and vertical dimensional changes of the materials. However, acidic conditions did not affect the roughness and the surface level of the materials.


Subject(s)
Humans , Oxides/chemistry , Root Canal Filling Materials/chemistry , Water/chemistry , Silicates/chemistry , Calcium Compounds/chemistry , Aluminum Compounds/chemistry , Reference Values , Surface Properties , Time Factors , Materials Testing , Reproducibility of Results , Analysis of Variance , Drug Combinations
9.
J. appl. oral sci ; 27: e20170449, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-975886

ABSTRACT

Abstract The stable long-term performance of resin cement under oral environmental conditions is a crucial factor to obtain a satisfactory success of the allceramic dental restoration. Objective: This study aimed at evaluating and comparing the surface morphology and mechanical property of conventional and self-adhesive resin cement after aqueous aging. Materials and Methods: Disc-shaped specimens of 3 conventional (C1: Multilink N, C2: Duolink, C3: Nexus 3) and 3 self-adhesive (S1: Multilink Speed, S2: Biscem, S3: Maxcem) types of resin cements were subjected to irradiation. After 24 h, the Knoop microhardness of each resin cement was evaluated. The specimens were immersed separately in distilled water and maintained at 37°C. A total of 5 specimens of each resin cement were collected at the following time intervals of immersion: 1, 6, 12 and 18 months. The samples were used to evaluate the Knoop parameters of microhardness, sorption and solubility. The surface morphology of the specimens after 18 months of immersion was observed by scanning electron microscopy. The sorption and solubility data were analyzed by two-way ANOVA. The Knoop microhardness was tested by the ANOVA repeated measures (P<0.05). Results: The sorption and solubility parameters of C1 and S1 exhibited significant fluctuations during the aqueous aging. The hardness of the S1 and S2 specimens decreased significantly after an 18-month water immersion. The S1, S2 and S3 specimens indicated higher filler exposure and stripping and apparent pores and cracks compared to specimens C1, C2 and C3, respectively. Conclusion: The surface of selfadhesive resin cements is more susceptible to aqueous damage than that of the conventional resin cements.


Subject(s)
Water/chemistry , Composite Resins/chemistry , Resin Cements/chemistry , Solubility , Surface Properties , Time Factors , Materials Testing , Microscopy, Electron, Scanning , Reproducibility of Results , Analysis of Variance , Hardness Tests , Immersion
10.
J. appl. oral sci ; 27: e20180126, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-975877

ABSTRACT

Abstract Objectives: The aim of this in vitro study was to evaluate the bonding strength of non-simplified dentin bonding systems (DBS) to dentin irradiated with a diode laser (970 nm) immediately and after 12 months of water storage following either primer or bond application. Material and methods: The experimental design included three different factors: DBS type [AdperTM Scotchbond Multipurpose (MP) and Clearfil™ SE Bond (CSE)], irradiation [without irradiation - control (C), irradiation after primer application (AP), and irradiation after bond application (AB)], and time [initial (I) and after 12 months of water storage (12 m)]. Sixty sound human third molars (n = 10) were obtained, and their flat occlusal dentin areas were prepared and standardized. Laser irradiation was performed in the contact mode perpendicular to the dental surface over an automatically selected scanning area at a pulse energy of 0.8 W, frequency of 10 Hz, and energy density of 66.67 J/cm2. After 7 days of treatment, the specimens were cut, and half of them were subjected to microtensile testing (500 N/0.05 mm/min), whereas the remaining sticks were examined after 12 months of water storage. The obtained data were analyzed by three-way analysis of variance (ANOVA) followed by a Tukey test (p<0.05). The observed fracture modes were investigated using a portable digital microscope with a magnification of 40x. Results: Among the utilized DBS, MP generally exhibited higher bond strengths, but did not always differ from CSE under similar conditions. The irradiation factor was statistically significant only for the MP/AB groups. After 12 months of storage, all groups demonstrated a significant reduction in the bond strength, whereas the results of fracture analysis showed a predominance of the adhesive type. Conclusions: The laser treatment of non-simplified DBS was not able to stabilize their bonding characteristics after 12 months.


Subject(s)
Humans , Dental Bonding/methods , Dentin-Bonding Agents/radiation effects , Resin Cements/radiation effects , Dentin/radiation effects , Lasers, Semiconductor , Reference Values , Surface Properties/radiation effects , Tensile Strength , Time Factors , Materials Testing , Water/chemistry , Reproducibility of Results , Analysis of Variance , Dentin-Bonding Agents/chemistry , Microscopy, Atomic Force , Resin Cements/chemistry , Dentin/drug effects , Polymerization/radiation effects
11.
J. appl. oral sci ; 27: e20180075, 2019. graf
Article in English | LILACS, BBO | ID: biblio-975874

ABSTRACT

Abstract Currently, there is no consensus in terms of defining the minimum radiant exposure values necessary for achieving adequate properties of composite resin. In addition, the long-term influence that radiant exposure has on the properties of composite resins is still questionable. Objective: The objective of this study was to evaluate the effect of radiant exposure and UV accelerated aging on the physico-chemical and mechanical properties of micro-hybrid and nanofilled composite resins. Material and Methods: A nanofilled (Filtek Supreme; 3M ESPE) and a micro-hybrid composite resin (Filtek Z250; 3M ESPE) were investigated under different radiant exposures (3.75, 9, and 24 J/cm2) and UV accelerated aging protocols (0, 500, 1000, and 1500 aging hours). The degree of conversion (DC), flexural strength (FS), modulus (M), water sorption (WS), and solubility (WL) were evaluated. The results obtained were analyzed using two-way ANOVA and Tukey's test. Comparisons were performed using a significance level of α=0.05. Results: The DC, FS, and M were found to be significantly influenced by both radiant exposure and accelerated aging time. The DC and EM increased with radiant exposure in the no-aging group (0-hour aging) for both micro-hybrid and nanofilled composites, whereas no correlation was found after accelerated aging protocols. WS and WL of micro-hybrid and nanofilled composite resins were scarcely affected by radiant exposure (p>0.05), whereas they were significantly reduced by accelerated aging (p<0.001). Conclusions: Although increasing radiant exposure affected the degree of conversion and mechanical properties of micro-hybrid and nanofilled composites, no influence on the hydrolytic degradation of the material was observed. In contrast, UV accelerated aging affected both the physico-chemical and mechanical properties of the composites.


Subject(s)
Ultraviolet Rays , Composite Resins/radiation effects , Composite Resins/chemistry , Radiation Dosage , Reference Values , Solubility , Surface Properties/radiation effects , Time Factors , Materials Testing , Water/chemistry , Microscopy, Electron, Scanning , Analysis of Variance , Spectroscopy, Fourier Transform Infrared , Phase Transition/radiation effects , Curing Lights, Dental , Photochemical Processes/radiation effects , Polymerization/drug effects , Flexural Strength/radiation effects
12.
J. appl. oral sci ; 27: e20180111, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-975872

ABSTRACT

Abstract Several anti-proteolytic dentin therapies are being exhaustively studied in an attempt to reduce dentin bond degradation and improve clinical performance and longevity of adhesive restorations. Objectives This study assessed the effect of epigallocatechin-3-gallate (EGCG) on long-term bond strength when incorporated into adhesives. Material and Methods Adhesive systems were formulated with EGCG concentrations of 0 wt%: (no EGCG; control); 0.5 wt% EGCG; 1.0 wt% EGCG, and 1.5 wt% EGCG. Flexural strength (FS), modulus of elasticity (ME), modulus of resilience (MR), compressive strength (CS), degree of conversion (DC), polymerization shrinkage (PS), percentage of water sorption (%WS), percentage of water solubility (%WL) and cytotoxicity properties were tested. Dentin microtensile bond strength (µTBS) was evaluated after 24 h and again after 6 months of water storage. The adhesive interface was analyzed using scanning electron microscopy (SEM). Results No significant differences were found among the groups in terms of FS, ME, MR, CS and PS. EGCG-doped adhesives increased the DC relative to the control group. EGCG concentrations of 1.0 wt% and 0.5 wt% decreased the WS of adhesives. WL decreased in all cases in which EGCG was added to adhesives, regardless of the concentration. EGCG concentrations of 1.0 wt% and 0.5 wt% reduced cytotoxicity. EGCG concentrations of 1.0 wt% and 0.5 wt% preserved µTBS after 6 months of storage, while 1.5 wt% EGCG significantly decreased µTBS. SEM: the integrity of the hybrid layer was maintained in the 0.5 wt% and 1.0 wt% EGCG groups. Conclusion EGCG concentrations of 1.0 wt% and 0.5 wt% showed better biological and mechanical performance, preserved bond strength and adhesive interface, and reduced cytotoxicity.


Subject(s)
Humans , Catechin/analogs & derivatives , Dentin-Bonding Agents/chemistry , Bisphenol A-Glycidyl Methacrylate/chemistry , Methacrylates/chemistry , Reference Values , Solubility , Surface Properties , Tensile Strength , Time Factors , Materials Testing , Camphor/analogs & derivatives , Camphor/chemistry , Water/chemistry , Microscopy, Electron, Scanning , Catechin/toxicity , Catechin/chemistry , Cell Line , Cell Survival/drug effects , Reproducibility of Results , Analysis of Variance , Dentin-Bonding Agents/toxicity , Bisphenol A-Glycidyl Methacrylate/toxicity , Compressive Strength , Dentin/drug effects , Dentin/chemistry , Elastic Modulus , Polymerization , Fibroblasts/drug effects , Flexural Strength , Methacrylates/toxicity
13.
Braz. oral res. (Online) ; 33: e024, 2019. tab, graf
Article in English | LILACS | ID: biblio-1001615

ABSTRACT

Abstract: The aim of this study is to evaluate the effect of chitosan or nanodiamond incorporation on the color stability and surface roughness of a bisacrylic resin subjected to artificial aging. Four bisacrylic resins were evaluated, namely, control, chitosan-modified material, nanodiamond-modified material, and chitosan-nanodiamond-modified material. Twenty-four specimens were prepared for each material. The surface roughness was determined using a profilometer with a cut-off of 0.25 mm. The baseline color was measured according to the CIE L*a*b* system using a reflectance spectrophotometer. After these tests, the specimens were individually immersed in cola soft drink, red wine, or distilled water (n = 8) for 28 days. After the aging, the surface roughness and final color were re-evaluated. The color stability was determined using the difference between the coordinates obtained before and after the aging process. The data on roughness and color change were evaluated using ANOVA and the Tukey test (α = 0.05). The results show that the incorporation of nanodiamonds and chitosan into a bisacrylic resin provided a better color stability to the materials (p = 0.007). The storage in red wine resulted in a higher variation in the surface roughness values, especially when only the nanodiamond was incorporated to the material (p < 0.05). The incorporation of both chitosan and nanodiamonds are promising in providing an improvement in the properties of the bisacrylic resin when they are simultaneously incorporated in the product.


Subject(s)
Acrylic Resins/chemistry , Color , Composite Resins/chemistry , Chitosan/chemistry , Nanodiamonds/chemistry , Reference Values , Spectrophotometry , Surface Properties , Time Factors , Wine , Materials Testing , Carbonated Beverages , Water/chemistry , Microscopy, Electron, Scanning , Reproducibility of Results , Analysis of Variance , Statistics, Nonparametric
14.
Int. braz. j. urol ; 44(5): 906-913, Sept.-Oct. 2018. graf
Article in English | LILACS | ID: biblio-975620

ABSTRACT

ABSTRACT In approximately 50% of cases of bladder carcinoma, an associated predisposing factor can be established. The main factors are exposure to tobacco, arsenic (As) ore and aromatic compounds. Arsenic is a metalloid with a low average concentration in the earth's crust, and one of the most dangerous substances for human health. The present study aims to evaluate the incidence of hospitalization and mortality from bladder neoplasia and its possible association with As concentration in water and soil in two of the most critical regions of Brazil: the states of São Paulo and Minas Gerais. We have investigated bladder cancer hospitalization and mortality in the states of Sao Paulo and Minas Gerais during 2010-2014. Water and soil samples were analyzed and As concentrations were established. Data were obtained through the Department of Informatics of the Brazilian Unified Health System. Correlation was made with water samples from São Paulo and with data on soil analysis from Minas Gerais. The results revealed no direct association in the distinctive municipalities. Areas with high environmental As concentration had a low bladder cancer rate, while areas with normal as levels had similar cancer rates. The quantitative variables did not present a normal distribution (p < 0.05). In conclusion, we did not observe a correlation between as concentration in water or soil and bladder cancer's hospitalization and mortality rates in the states of São Paulo and Minas Gerais.


Subject(s)
Humans , Male , Female , Aged , Arsenic/adverse effects , Soil/chemistry , Urinary Bladder Neoplasms/chemically induced , Water/chemistry , Environmental Exposure/adverse effects , Arsenic/analysis , Urinary Bladder Neoplasms/mortality , Brazil/epidemiology , Environmental Exposure/analysis , Middle Aged
15.
Braz. oral res. (Online) ; 32: e40, 2018. tab, graf
Article in English | LILACS | ID: biblio-889471

ABSTRACT

Abstract This research explored the potential of Camellia sinensis-derived teas and active compounds to be used as treatments to prevent dentin wear. Human root dentin slabs were randomly assigned to 5 groups (n = 10) as follows: distilled water (DW, control), epigallocatechin-3-gallate (EGCG), theaflavin gallate derivatives (TF), commercial green tea (GT), and commercial black tea (BT). The samples were submitted to a pellicle formation and an erosive cycling model (5x/day, demineralization using 0.01 M hydrochloric acid/60 s) followed by remineralization (human stimulated saliva/60 min) for three days. The samples were treated for 5 min using the test group solutions between the erosive cycles. Dentin changes were assessed with profilometry analysis and FT-Raman spectroscopy. The data regarding wear were analyzed by ANOVA followed by Tukey's test (p < 0.05). EGCG, TF derivatives, and both regular teas significantly suppressed erosive dentin loss (38-47%, p < 0.05). No obvious changes in the Raman spectra were detected in the specimens; however, the DW group had a minor relationship of 2880/2940 cm−1. The phenolic contents in both green and black tea and the important catechins appear to have protective effects on dentin loss.


Subject(s)
Humans , Biflavonoids/pharmacology , Camellia sinensis/chemistry , Catechin/analogs & derivatives , Dentin/drug effects , Gallic Acid/analogs & derivatives , Tea/chemistry , Tooth Erosion/prevention & control , Catechin/pharmacology , Fluorides/analysis , Fluorides/pharmacology , Gallic Acid/pharmacology , Water/chemistry
16.
J. appl. oral sci ; 26: e20170536, 2018. tab, graf
Article in English | LILACS, BBO | ID: biblio-954512

ABSTRACT

Abstract While the combined effect of microwave irradiation with cleansing solutions on denture base materials has been investigated, the effects of only using microwave irradiation and, more importantly, in a long-term basis, was not studied yet. Objective The purpose of this study was to evaluate the effect of a long-term repeated microwaving on the dimensional, color and translucency stability of acrylic and polyamide denture base materials. Material and Methods Thirty two specimens (32 mm x 10 mm x 2.5 mm) from polyamide (Valplast) and PMMA (Vertex Rapid Simplified) denture base materials were made. Eight specimens from each material were immersed in distilled water (control) and 8 were subjected to microwave exposure at 450 W for 3 minutes for a period simulating 224 days of daily disinfection. Linear dimension, color change (ΔE*) and translucency parameter (TP) were measured at baseline and after certain intervals up to 224 cycles of immersion, using a digital calliper and a portable colorimeter. The results were analysed using two-way repeated measures ANOVA to estimate possible differences among predetermined cycles and material type. Regression analysis was also performed to estimate the trend of changes with time. Statistical evaluations performed at a significance level of 5%. Results Data analysis showed significant changes in length at baseline with an increasing number of cycles (p<0.05) and a significant interaction of cycle-material (p<0.001). The ΔΕ* parameter was significantly higher with a higher number of cycles (p<0.001), but it did not vary between materials (p>0.05). TP decreased similarly in both materials following microwave action but in a significantly higher level for Valplast (p<0.001). Conclusions The results indicated that long-term repeated microwaving affects linear dimensional, color and translucency changes of both materials. Differences between PMMA and polyamide material were noted only in dimension and translucency changes.


Subject(s)
Prosthesis Coloring , Polymethyl Methacrylate/radiation effects , Denture Bases , Microwaves , Nylons/radiation effects , Reference Values , Surface Properties , Time Factors , Materials Testing , Water/chemistry , Disinfection/instrumentation , Disinfection/methods , Reproducibility of Results , Analysis of Variance , Color , Colorimetry/methods , Polymethyl Methacrylate/chemistry , Interferometry/methods , Nylons/chemistry
17.
J. appl. oral sci ; 26: e20170374, 2018. tab
Article in English | LILACS, BBO | ID: biblio-893735

ABSTRACT

Abstract Objectives To determine the concentration of calcium, iron, manganese and zinc ions after the application of chelator to Enterococcus faecalis biofilms. Material and Methods Fifty bovine maxillary central incisors were prepared and inoculated with E. faecalis for 60 days. The following were used as irrigation solutions: 17% EDTA (pH 3, 7 and 10), 2.5% sodium hypochlorite (NaOCl) combined with 17% EDTA (pH 3, 7 and 10), distilled water (pH 3, 7 and 10), and 2.5% NaOCl. Each solution was kept in the root canal for five minutes. Fifteen uncontaminated root canals were irrigated with 17% EDTA (pH 3, 7 and 10). Six teeth were used as bacterial control. The number of calcium, iron, manganese and zinc ions was determined using flame atomic absorption spectrometry. Mean ± standard deviation (SD) values were used for descriptive statistics. Results Calcium chelation using 17% EDTA at pH 7 was higher than at pH 3 and 10, regardless of whether bacterial biofilm was present. The highest concentration of iron occurred at pH 3 in the presence of bacterial biofilm. The highest concentration of manganese found was 2.5% NaOCl and 17% EDTA at pH 7 in the presence of bacterial biofilm. Zinc levels were not detectable. Conclusions The pH of chelating agents affected the removal of calcium, iron, and manganese ions. The concentration of iron ions in root canals with bacterial biofilm was higher after the use of 17% EDTA at pH 3 than after the use of the other solutions at all pH levels.


Subject(s)
Animals , Cattle , Chelating Agents/pharmacology , Enterococcus faecalis/drug effects , Biofilms/drug effects , Dental Pulp Cavity/drug effects , Dental Pulp Cavity/microbiology , Root Canal Irrigants/pharmacology , Root Canal Irrigants/chemistry , Sodium Hypochlorite/pharmacology , Sodium Hypochlorite/chemistry , Spectrophotometry, Atomic , Materials Testing , Water/chemistry , Chelating Agents/chemistry , Calcium/analysis , Edetic Acid/pharmacology , Edetic Acid/chemistry , Enterococcus faecalis/chemistry , Dental Pulp Cavity/chemistry , Hydrogen-Ion Concentration , Ions , Iron/analysis , Manganese/analysis
18.
J. appl. oral sci ; 26: e20170465, 2018. tab, graf
Article in English | LILACS, BBO | ID: biblio-893724

ABSTRACT

Abstract Objective: To evaluate the absorption/fluid uptake, solubility and porosity of White mineral trioxide aggregate (MTA) Angelus, Biodentine (BIO), and zinc oxide-eugenol (ZOE). Material and Methods: Solubility was evaluated after immersion in distilled water for 7 and 30 days. Porosity was evaluated using digital inverted microscope, scanning electron microscope (SEM) and micro-computed tomography (micro-CT). For the fluid uptake test, specimens were immersed in Hank's balanced salt solution (HBSS) for 1, 7, 14 and 28 days. Fluid absorption, solubility and porosity of the materials were measured after each period. Statistical evaluation was performed using one-way analysis of variance (ANOVA) and Tukey tests, with a significance level at 5%. Results: After 7 and 30 days, BIO showed the highest solubility (p<0.05). All methods demonstrated that MTA had total porosity higher than BIO and ZOE (p<0.05). Micro-CT analysis showed that MTA had the highest porosity at the initial period, after its setting time (p<0.05). After 7 and 30 days, ZOE had porosity lower than MTA and BIO (p<0.05). Absorption was similar among the materials (p>0.05), and higher fluid uptake and solubility were observed for MTA in the fluid uptake test (p<0.05). Conclusions: BIO had the highest solubility in the conventional test and MTA had higher porosity and fluid uptake. ZOE had lower values of solubility, porosity and fluid uptake. Solubility, porosity and fluid uptake are related, and the tests used provided complementary data.


Subject(s)
Oxides/chemistry , Zinc Oxide-Eugenol Cement/chemistry , Silicates/chemistry , Calcium Compounds/chemistry , Aluminum Compounds/chemistry , Solubility , Surface Properties , Time Factors , Materials Testing , Water/chemistry , Microscopy, Electron, Scanning , Reproducibility of Results , Analysis of Variance , Porosity , Drug Combinations , X-Ray Microtomography , Immersion
19.
J. appl. oral sci ; 26: e20170270, 2018. tab, graf
Article in English | LILACS, BBO | ID: biblio-893712

ABSTRACT

Abstract Although resin composites are widely used in the clinical practice, the development of recurrent caries at composite-tooth interface still remains as one of the principal shortcomings to be overcome in this field. Objectives To evaluate the activity against S. mutans biofilm of model resin composites incorporating different concentrations of ZnO-nanoparticles (ZnO-NP) and characterize their physicochemical properties. Materials and Methods Different concentrations of ZnO-NP (wt.%): E1=0, E2=0.5, E3=1, E4=2, E5=5 and E6=10 were incorporated into a model resin composite consisting of Bis-GMA-TEGDMA and barium borosilicate particles. The activity against S. mutans biofilm was evaluated by metabolic activity and lactic acid production. The following physicochemical properties were characterized: degree of conversion (DC%), flexural strength (FS), elastic modulus (EM), hardness (KHN), water sorption (Wsp), water solubility (Wsl) and translucency (TP). Results E3, E4, E5 and E6 decreased the biofilm metabolic activity and E5 and E6 decreased the lactic acid production (p<0.05). E6 presented the lowest DC% (p<0.05). No significant difference in FS and EM was found for all resin composites (p>0.05). E5 and E6 presented the lowest values of KHN (p<0.05). E6 presented a higher Wsp than E1 (p<0.05) and the highest Wsl (p<0.05). The translucency significantly decreased as the ZnO- NP concentration increased (p<0.05). Conclusions The incorporation of 2 - 5 wt.% of ZnO-NP could endow antibacterial activity to resin composites, without jeopardizing their physicochemical properties.


Subject(s)
Streptococcus mutans/drug effects , Zinc Oxide/pharmacology , Zinc Oxide/chemistry , Composite Resins/pharmacology , Composite Resins/chemistry , Nanoparticles/chemistry , Polyethylene Glycols/pharmacology , Polyethylene Glycols/chemistry , Polymethacrylic Acids/pharmacology , Polymethacrylic Acids/chemistry , Reference Values , Solubility , Streptococcus mutans/growth & development , Surface Properties , Materials Testing , Water/chemistry , Microscopy, Electron, Scanning , Linear Models , Reproducibility of Results , Analysis of Variance , Bisphenol A-Glycidyl Methacrylate/pharmacology , Bisphenol A-Glycidyl Methacrylate/chemistry , Silicates/pharmacology , Silicates/chemistry , Barium Compounds/pharmacology , Barium Compounds/chemistry , Pliability , Biofilms/growth & development , Biofilms/drug effects , Elastic Modulus , Hardness Tests
20.
J. appl. oral sci ; 26: e20170383, 2018. graf
Article in English | LILACS, BBO | ID: biblio-893710

ABSTRACT

Abstract The proper selection of polymerization cycle is important to prevent overheating of the monomer that could cause degradation, porosity and, consequently, deleterious effects on the denture base properties. Objective This study evaluated the porosity, water sorption and solubility of acrylic resins (Vipi Cril-VC and Vipi Wave-VW) after conventional or microwave polymerization cycles. Material and Methods Specimens (n = 10) were made and cured: 1-WB = 65°C during 90 min + boiling during 90 min (VC cycle - control group); 2-M25 = 10 min at 270 W + 5 min at 0 W + 10 min at 360 W (VW cycle); 3-M3 = 3 min at 550 W; and 4-M5 = 5 min at 650 W. Afterward, they were polished and dried in a dessicator until a constant mass was reached. Specimens were then immersed in distilled water at 37°C and weighed regularly until a constant mass was achieved. For porosity, an additional weight was made with the specimen immediately immersed in distilled water. For water sorption and solubility, the specimens were dried again until equilibrium was reached. Data were submitted to 2 way-ANOVA and Tukey HSD (α=0.05). Results Porosity mean values below 1.52% with no significant difference among groups for both materials were observed. Resins showed water sorption and solubility values without a significant difference. However, there was a significant difference among groups for these both properties (P<0.013). The highest sorption (2.43%) and solubility (0.13%) values were obtained for WB and M3, respectively. Conclusions The conventional acrylic resin could be polymerized in a microwave since both the materials showed similar performance in the evaluated properties. Shorter microwave cycles could be used for both the materials without any detectable increase in volume porosity.


Subject(s)
Acrylic Resins/chemistry , Water/chemistry , Denture Bases , Polymerization , Solubility , Time Factors , Materials Testing , Reproducibility of Results , Analysis of Variance , Porosity , Microwaves
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