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1.
Braz. dent. sci ; 24(1): 1-9, 2021. tab, ilus
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-1145518

RESUMEN

Objective: To determine the force decay and discoloration in Generation I and Generation II elastomeric chain on artificial saliva immersion. Material and methods: Generation I and Generation II elastomeric chains stretched on an acrylic board and immersed in artificial saliva for 1, 7, 14, 21, and 28 days according to the group of days. On each specified day, the force of each sample measured by an orthodontic force gauge and the magnitude of the force obtained is entered to the formula to find out the force decay in percentage, whereas discoloration of each sample analyzed by the color reader with CIE Lab analysis. Results: The force decay between Generation I and Generation II elastomeric chains showed a statistically significant difference in every group of days, in which Generation II is more effective in maintaining stretch force. Similar to force decay, the discoloration in Generation I elastomeric chains on the 14th day showed significant value and Generation II elastomeric chains were more stable in maintaining color compared to Generation I. Conclusions: over the entire research period time, Generation II elastomeric chains are more stable in maintaining stretch forces and color compared to Generation I elastomeric chains. (AU)


Objetivo: Determinar a queda de força e descoloração nos elásticos ortodônticos tipo corrente de Geração I e Geração II na imersão em saliva artificial. Material e métodos: Elásticos Geração I e Geração II foram esticados em placas de acrílico e imersas em saliva artificial por 1, 7, 14, 21 e 28 dias, de acordo com o grupo de dias. Em cada dia especificado, a força de cada amostra medida por um medidor de força ortodôntica e a magnitude da força obtida são inseridos na fórmula para descobrir sua queda em porcentagem, enquanto a descoloração de cada amostra foi analisada pelo leitor de cores "CIE Lab". Resultados: A queda da força entre os elásticos Geração I e Geração II apresentou diferença estatisticamente significativa em todos os grupos de dias, sendo que a de Geração II foi mais efetiva na manutenção da força de alongamento. Semelhante à queda de força, a descoloração nos elásticos da Geração I mostrou um valor significativo no 14º dia, e elásticos da Geração II foram mais estáveis na manutenção da cor em comparação com a Geração I. Conclusões: durante todo o período de pesquisa, os elásticos tipo corrente da Geração II foram mais estáveis na manutenção das forças de alongamento e da cor em comparação com os elásticos da Geração I (AU)


Asunto(s)
Saliva Artificial , Técnicas de Movimiento Dental , Fuerza de la Mordida
2.
Oral Health Prev Dent ; 18(1): 713-718, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32895654

RESUMEN

PURPOSE: To investigate dentin abrasivity and cleaning efficacy of novel/alternative toothpastes containing diamond particles, active carbon, sea salt or organic oils. MATERIALS AND METHODS: Seventy-two bovine dentin samples (for measuring abrasivity) and 60 human dentin samples (for assessing cleaning efficacy) were used in this study. Samples were divided into six groups as follows: group 1: Elmex Kariesschutz (hydrated silica); group 2: Lavera Neutral Zahngel (sea salt); group 3: Curaprox Black is White (active carbon); group 4: Swiss Smile Diamond Glow (diamond powder); group 5: Ringana Fresh Tooth Oil (hydrated silica); and group 6: artificial saliva. Samples were brushed for a total of 26 min at 120 strokes/min, replacing slurries (1 part respective toothpaste and 2 parts artificial saliva) every 2 min. Finally, abrasive dentin wear was measured profilometrically and cleaning efficacy planimetrically. RESULTS: The highest abrasivity values were observed for Lavera Neutral Zahngel (sea salt 9.2 µm) and Elmex Kariesschutz group (hydrated silica 6.0 µm). The lowest abrasivity value was observed for Ringana Fresh Tooth Oil group (hydrated silica 1.3 µm). The highest cleaning efficacy was observed for Elmex Kariesschutz group (86.7%) and the lowest cleaning efficacy was observed for Ringana Fresh Tooth Oil group (31.3%). CONCLUSION: The addition of diamond powder or active carbon to toothpastes could offer high cleaning efficacy with low dentin abrasivity. The addition of sea salt to traditional abrasives might cause high abrasive dentin wear without adding further cleaning benefit.


Asunto(s)
Abrasión de los Dientes , Pastas de Dientes , Animales , Bovinos , Dentina , Humanos , Saliva Artificial , Cepillado Dental
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(4): 499-504, 2020 Jul.
Artículo en Chino | MEDLINE | ID: mdl-32691557

RESUMEN

Objective: The purpose of this study was to investigate the effect of G4.5 carboxyl-terminated poly dendrimer (PAMAM-COOH) on the dentin remineralization and the matrix metalloproteinases (MMPs) activity. Methods: The dentine samples were averagely divided into four groups: 100 mg/mL PAMAM-COOH group (A group), 10 mg/mL PAMAM-COOH group (B group), 2% (wt) chlorhexidine (CHX) group (C group) and deionized water group (Control group). MMP Activity Assay Kit was used to detect the activity of dentin endogenous MMPs in the four groups. The loss of dry mass of dentin after 30 d were measured. In situ zymography analysis was performed to detect the effects of PAMAM dendrimer in each group (except A group) on gelatinase activity in dentin. After incubation in artificial saliva for 7 and 14 d incubated, the remineralization of each group (except A group) in dentin surfaces were examined using a field emission-scanning electron microscope (FESEM). Results: Compared with the control group, the dentin endogenous MMPs activity in A, B and C groups were all decreased ( P<0.05). The activity of endogenous MMPs in C group was lower than that of A and B groups ( P<0.001), but the difference between A and B groups was not statistically significant. The loss of dry mass in A, B and C groups were lower than that in control group ( P<0.05), but there were no significant difference in A, B and C groups. The in situzymography analysis showed that 48 h later, the dentin gelatinase activity in B group was inhibited compared with the control group, but the inhibitory effect was weaker than that of CHX. After 7 d and 14 d, there were no obvious mineralization in the control group, while distinct mineralization were observed in B group. The mineralization effect in group B was better than group C. Conclusion: G4.5 PAMAM-COOH could introduce remineralizationin and demineralizeddentin by effectively inhibiting endogenous MMPs and gelatinase, thus contributes as novel material to enhancing durability of adhesion.


Asunto(s)
Dendrímeros , Dentina , Metaloproteinasas de la Matriz , Remineralización Dental , Dendrímeros/farmacología , Dentina/enzimología , Dentina/metabolismo , Activación Enzimática/efectos de los fármacos , Humanos , Metaloproteinasas de la Matriz/metabolismo , Saliva Artificial
4.
Emerg Microbes Infect ; 9(1): 1415-1417, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32496967

RESUMEN

SARS-CoV-2, the causative agent of the COVID-19 pandemic, may be transmitted via airborne droplets or contact with surfaces onto which droplets have deposited. In this study, the ability of SARS-CoV-2 to survive in the dark, at two different relative humidity values and within artificial saliva, a clinically relevant matrix, was investigated. SARS-CoV-2 was found to be stable, in the dark, in a dynamic small particle aerosol under the four experimental conditions we tested and viable virus could still be detected after 90 minutes. The decay rate and half-life was determined and decay rates ranged from 0.4 to 2.27 % per minute and the half lives ranged from 30 to 177 minutes for the different conditions. This information can be used for advice and modelling and potential mitigation strategies.


Asunto(s)
Aerosoles/química , Betacoronavirus/crecimiento & desarrollo , Infecciones por Coronavirus/virología , Medios de Cultivo/química , Neumonía Viral/virología , Saliva Artificial/química , Salvia/virología , Microbiología del Aire , Betacoronavirus/química , Betacoronavirus/genética , Betacoronavirus/efectos de la radiación , Infecciones por Coronavirus/transmisión , Oscuridad , Humanos , Humedad , Cinética , Pandemias , Neumonía Viral/transmisión
5.
Clin Oral Investig ; 24(6): 1889-1908, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32385655

RESUMEN

BACKGROUND: Taste disorder is a frequent drug-induced or disease-related oral trouble. Various pharmacological, surgical, or physical treatments have previously been proposed for taste function recovery. OBJECTIVES: The aim of the present systematic review was to assess the effects of palliative and curative interventions on taste recovery in light of recent literature. MATERIALS AND METHODS: In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, a search of the literature published up to June 2019 was conducted using MEDLINE via PubMed, EMBASE, and The US National Institutes of Health Trials Register (PROSPERO registration reference: CRD 42019139315). The methodological quality of the included trials was rated with the "Delphi list For Quality Assessment of Randomized Clinical Trials" and the Newcastle-Ottawa scale. RESULTS: From the 1842 titles first identified, 28 articles met the inclusion criteria. Interventions included zinc (aspartate, sulfate, gluconate, acetate, picolinate, and Polaprezinc®), esomeprazole, L-thyroxin, bethanechol, oral glutamine, delta-9-tetrahydrocannabinol, alpha-lipoic acid, Ginkgo biloba, artificial saliva, pilocarpine, local anesthesia, and improved oral hygiene. The quality of evidence ranged from poor to high. CONCLUSION: Improving oral hygiene may promote taste ability. Zinc may prevent and alleviate taste disorder in patients undergoing head and neck radiotherapy. CLINICAL RELEVANCE: The systematic review provided evidence about the clinical efficacy of oral procedures, zinc supplementation, and palliative cares in dysgeusic patients. Further research is needed to find effective treatments with low adverse effects.


Asunto(s)
Higiene Bucal , Trastornos del Gusto , Humanos , Saliva Artificial , Trastornos del Gusto/etiología , Trastornos del Gusto/terapia , Resultado del Tratamiento
6.
Biomed Res Int ; 2020: 2920804, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32185200

RESUMEN

Aim: This study aims to evaluate the accuracy of scanned images of 4 clinically used intraoral scanners (CS3600, i500, Trios3, Omnicam) when scanning the surface of full arch models with various kinds of orthodontic brackets in the presence of artificial saliva. Materials and Methods. Four study models were prepared; bonded with ceramic, metal, and resin brackets, respectively, and without brackets. Reference images were taken by scanning the models with an industrial scanner. Study models were then applied with an artificial saliva and scanned 10 times, respectively, with the above 4 intraoral scanners. All images were converted to STL file format and analyzed with 3D analysis software. By superimposing with the reference images, mean maximum discrepancy values and mean discrepancy values were collected and compared. For statistical analysis, two-way ANOVA was used. Results: Omnicam (1.247 ± 0.255) showed higher mean maximum discrepancy values. CS3600 (0.758 ± 0.170), Trios3 (0.854 ± 0.166), and i500 (0.975 ± 0.172) performed relatively favourably. Resin (1.119 ± 0.255) and metal (1.086 ± 0.132) brackets showed higher mean maximum discrepancy values. Nonbracket (0.776 ± 0.250) and ceramic bracket (0.853 ± 0.269) models generally showed lower mean maximum discrepancy values in studied scanners. In mean discrepancy values, the difference between scanners was not statistically significant whereas among brackets, resin bracketed models (0.093 ± 0.142) showed the highest value. Conclusion: Intraoral scanners and brackets had significant influences on the scanned images with application of artificial saliva on the study models. It may be expected to have similar outcomes in an intraoral environment. Some data showed the discrepancy values up to about 1.5 mm that would require more caution in using intraoral scanners for production of detailed appliances and records.


Asunto(s)
Arco Dental/diagnóstico por imagen , Técnica de Impresión Dental/instrumentación , Modelos Dentales , Cerámica/farmacología , Diseño Asistido por Computadora/instrumentación , Humanos , Imagenología Tridimensional/métodos , Modelos Anatómicos , Soportes Ortodóncicos , Resinas Sintéticas/farmacología , Saliva Artificial/farmacología , Programas Informáticos
7.
Int J Mol Sci ; 21(6)2020 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-32183193

RESUMEN

Saliva plays a crucial role in oral cavity. In addition to its buffering and moisturizing properties, saliva fulfills many biofunctional requirements, including antibacterial activity that is essential to assure proper oral microbiota growth. Due to numerous extra- and intra-systemic factors, there are many disorders of its secretion, leading to oral dryness. Saliva substitutes used in such situations must meet many demands. This study was design to evaluate the effect of core-shell magnetic nanoparticles (MNPs) adding (gold-coated and aminosilane-coated nanoparticles NPs) on antimicrobial (microorganism adhesion, biofilm formation), rheological (viscosity, viscoelasticity) and physicochemical (pH, surface tension, conductivity) properties of three commercially available saliva formulations. Upon the addition of NPs (20 µg/mL), antibacterial activity of artificial saliva was found to increase against tested microorganisms by 20% to 50%. NPs, especially gold-coated ones, decrease the adhesion of Gram-positive and fungal cells by 65% and Gram-negative bacteria cells by 45%. Moreover, the addition of NPs strengthened the antimicrobial properties of tested artificial saliva, without influencing their rheological and physicochemical properties, which stay within the range characterizing the natural saliva collected from healthy subjects.


Asunto(s)
Antiinfecciosos/química , Nanopartículas de Magnetita/química , Saliva Artificial/química , Antiinfecciosos/farmacología , Adhesión Bacteriana/efectos de los fármacos , Biopelículas/efectos de los fármacos , Candida/efectos de los fármacos , Elasticidad , Conductividad Eléctrica , Oro/química , Pseudomonas/efectos de los fármacos , Saliva Artificial/farmacología , Silanos/química , Streptococcus/efectos de los fármacos , Tensión Superficial , Viscosidad
9.
Oper Dent ; 45(3): E114-E123, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32053454

RESUMEN

OBJECTIVE: The objective of this study was to evaluate the effect of erosion or erosion-abrasion on bioactive materials and adjacent enamel/dentin areas. METHODS AND MATERIALS: Enamel and dentin blocks (4×4×2 mm) were embedded side by side in acrylic resin, and a standardized cavity (1.2×4×1.5 mm) was prepared between them. Preparations were restored with the following materials: composite resin (Filtek Z350, control); experimental composite containing di-calcium phosphate dihydrate particles (DCPD); Giomer (Beautifil II), high viscosity glass ionomer cement (GIC, Fuji IX); and a resin-modified GIC (Fuji II LC). The specimens were submitted to two cycling models (n=10): erosion or erosion-abrasion. The challenges consisted of five-minute immersion in 0.3% citric acid solution, followed by 60-minute exposure to artificial saliva. Toothbrushing was carried out twice daily, 30 minutes after the first and last exposures to acid. Dental and material surface loss (SL, in µm) were determined by optical profilometry. Data were analyzed with Kruskal-Wallis and Dunn tests (α=0.05). RESULTS: Under erosion, for enamel, only the GIC groups presented lower SL values than Z350 (p<0.001 for Fuji IX and p=0.018 for Fuji II LC). For dentin, none of the materials showed significantly lower SL values than Z350 (p>0.05). For material, the GICs had significantly higher SL values than those of Z350 (p<0.001 for Fuji IX and p=0.002 for Fuji II LC). Under erosion-abrasion, the enamel SL value was significantly lower around Fuji II LC compared with the other materials (p<0.05). No significant differences were observed among groups for dentin SL (p=0.063). The GICs and Giomer showed higher SL values than Z350 (p<0.001 for the GICs and p=0.041 for Giomer). CONCLUSION: Both GIC-based materials were susceptible to erosive wear; however, they promoted the lowest erosive loss of adjacent enamel. Against erosion-abrasion, only Fuji II LC was able to reduce enamel loss. For dentin, none of the materials exhibited a significant protective effect.


Asunto(s)
Esmalte Dental , Cementos de Ionómero Vitreo , Materiales Dentales , Dentina , Saliva Artificial , Cepillado Dental
10.
Dent Mater ; 36(3): 456-467, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32008748

RESUMEN

OBJECTIVE: The aim is to investigate the potential significance of combining minimally invasive high-intensity focused ultrasound (HIFU) with hydroxyapatite (HA) nanorods treatment for the remineralization of demineralized coronal dentine-matrix. METHODS: HA having nanorods structure were synthetized using ultrasonication with precipitation method. HA nanorods were characterized by TEM for average-size/shape. Following phosphoric acid demineralization, dentine specimens were treated with HA-nanorods with/without subsequent HIFU exposure for 5 s, 10 s and 20 s then stored in artificial saliva for 1-month. Dentine specimens were characterized using different SEM and Raman spectroscopic techniques. In addition, the biochemical stability and HA-nanorods were examined using ATR-FTIR to observe attachment of nanoparticles. Also, surface nanoindentation properties were evaluated using AFM in tapping-mode. RESULTS: HA-nanorods displayed well-defined, homogenous plate-like nanostructure. TEM revealed intact collagen-fibrils network structure with high density due to obliteration of interfibrillar spaces with clear evidence of remineralization in combined HA/HIFU treatment. With HA-nanorods treatment collagen-network structure was visible, consisting of fibrils interlaced into a compact pattern with evidence of minerals deposition. AFM investigation revealed clear mineral formation with the increase of HIFU exposure time. Bands associated with inorganic phase dominate well in HIFU exposed specimens with PO stretching within dentine mineral identified at 960 cm-1. Characteristic dentine structure for control and HIFU 20 s specimens is reflected as oscillatory mean Amide-I intensity with measurement giving a precise sinusoidal response of polarization angle ß within dentinal tissue. Nanoindentation testing showed a gradual significant increase in elastic-modulus with the increase in HIFU exposure time after 1-month storage. FTIR spectrum of the HIFU exposed dentine displayed bands at 1650 cm-1, 1580 cm-1 and 1510 cm-1 that can be attributed to Amide-I, II and III. SIGNIFICANCE: The synergetic effect of HIFU exposure on remineralization potential of demineralized dentine-matrix following nano-hydroxyapatite treatment was revealed. This synergetic effect is dependent on HIFU exposure time.


Asunto(s)
Durapatita , Nanotubos , Dentina , Saliva Artificial , Remineralización Dental
11.
Dent Mater J ; 39(3): 429-434, 2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-31969546

RESUMEN

This study aimed to evaluate the effects of artificial saliva contamination on a glass ionomer cement (GIC), a resin-modified GIC (RMGIC), and a composite resin (CR) that was used with two different etching adhesive systems. Three surface conditions were created on bovine teeth using artificial saliva: control (group I), mild saliva contamination (group II), and severe saliva contamination (group III). The microtensile bond strength (µTBS) of CR with dentin was significantly lower in group III than in group I. However, the µTBS of GIC and RMGIC with both enamel and dentin showed no significant intergroup differences. Moreover, CR exhibited significantly greater microleakage on cementum in group III than in group I, whereas both GIC and RMGIC showed no significant differences for both enamel and cementum. Thus, GIC and RMGIC may be suitable for preventing secondary caries after class V restorative treatments when contamination by saliva cannot be avoided.


Asunto(s)
Recubrimiento Dental Adhesivo , Filtración Dental , Animales , Bovinos , Resinas Compuestas , Restauración Dental Permanente , Dentina , Cementos de Ionómero Vitreo , Ensayo de Materiales , Cementos de Resina , Saliva Artificial
12.
Dent Mater ; 36(3): 431-441, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31992484

RESUMEN

OBJECTIVE: The Ti-6Al-4V (TAV) alloy is commercially used as a dental implant material. This work seeks to elucidates the origins of degradation of Ti-6Al-4V (TAV) implant alloys that result in peri-implant bone loss. 
Methods: In this work, a combination of microstructure, surface, and solution analyses was utilized to study the corrosion mechanism of the TAV alloy in oral environments. The corrosion of TAV alloys in the F--enriched environment of a crevice was evaluated through nanoscale surface analysis. And, the findings were further rationalized via electrochemical means. 
 RESULTS: Our results suggest the bone loss was caused by crevice corrosion and the consequential release of by-products, and the crevice corrosion was potentially induced by the buildup of corrosive species such as fluorides, which are common additives in dental products. In turn, the corrosion properties of the TAV alloy were evaluated in fluoride enriched environments. Nanoscale analysis of corroded surfaces, carried out using vertical scanning interferometry (VSI) showed that the corrosion susceptibility of the constituent phases dictates the corrosion product species. In specific, the aluminum-rich α phase preferentially dissolves under potential-free conditions and promotes the formation of insoluble Al-Ti oxides. Notably, under conditions of applied potential, oxidative dissolution of the vanadium-rich ß phase is favored, and the vanadium release is promoted. 
 SIGNIFICANCE: These findings elucidate the origins of degradation of TAV-implants that result in the release of corrosion by-products into the local biological environment. More important, they offer guidelines for materials design and improvement to prevent this nature of degradation of dental implants.


Asunto(s)
Implantes Dentales , Aleaciones , Corrosión , Aleaciones Dentales , Ensayo de Materiales , Saliva Artificial , Propiedades de Superficie , Titanio
13.
Talanta ; 209: 120501, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31892087

RESUMEN

In the present study, we have developed a capacitance electrochemical biosensor based on silicon nitride substrate (Si3N4/SiO2/Si[P]/Al) for Tumour Necrosis Factor Alpha (TNF-α) cytokines detection. Micro-contact printing, Fluorescence microscopy characterization and contact angle measurement (CAM) were carried out during the bio-functionalization of the biosensor surface. Mott-Schottky analyses were applied for TNF-α detection within the range of 1 pg/mL to 30 pg/mL in which the immunosensor has exhibited a good linearity, a sensitivity of 4 mV.pM-1 and 4.4 mV.pM-1 in PBS and artificial saliva (AS) respectively. While the LOD was found at 0.38 pg/mL and 1 pg/mL in PBS and AS respectively. The developed immunosensor has also demonstrated a high and good selectivity for TNF-α detection in human AS when compared to other interferences like Cortisol and Interleukin-10. The performances of the developed biosensor are very promising for biomedical application to predict the first sign of inflammation.


Asunto(s)
Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Saliva Artificial/química , Compuestos de Silicona/química , Transductores , Factor de Necrosis Tumoral alfa/análisis , Anticuerpos Inmovilizados/inmunología , Anticuerpos Monoclonales/inmunología , Capacidad Eléctrica , Técnicas Electroquímicas/instrumentación , Electrodos , Colorantes Fluorescentes/química , Humanos , Inmunoensayo/métodos , Límite de Detección , Rodaminas/química , Dióxido de Silicio/química , Factor de Necrosis Tumoral alfa/inmunología
14.
Int J Pharm ; 574: 118922, 2020 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-31836482

RESUMEN

The purpose of this study was to develop a new solid paediatric formulation for propranolol hydrochloride (PR). This drug is used to treat various paediatric diseases, and recently received clearance to treat haemangioma. However, PR has a bitter salty taste that does not facilitate high rates of compliance among children, especially in liquid formulations. In addition, the solid formulations are designed for adults and often their dosage is not suitable for children that require a flexible dose based on their weight. Therefore, matrix microbeads of EUDRAGIT® E PO containing PR were manufactured to overcome these limitations. Nine different samples were prepared using the prilling-congealing technique with high yield. Using 2 nozzles, 300 and 450 µm (code n), the diameters obtained of microbeads (from 333 to 699 µm) were homogenous and appropriate to be swallowed by children. In this study, the ratio drug:matrix for the microbeads was also examined in detail: 1:25 (F1), 1:15 (F2) and 1:10 (F3) in aqueous and tert-butyl alcohol/aqueous (code t) media. Most of the examined microbeads were characterized by high percentage of encapsulation efficiency (22-100%) and drug loading (22-77 mg of drug per g of matrix) effective for the administration of low and high doses of PR. SEM analysis revealed a matrix with a radial or a spongy structure, with numerous pores that generated soft floating microbeads in aqueous solution. Release studies confirmed a low release and dissolution of the drug in artificial saliva, mainly F1n > F1 > F2nt, and a prompt dissolution in simulated gastric media. Finally, electronic tongue measurements revealed the ability of these formulations to mask the bitter drug taste, especially for the sample with a ratio 1:25 (F1n and F1). These samples were chemically and physically stable for six months. In conclusion, the projected microbeads F1, and F1n reached the goal of the study, and could be proposed as new solid oral formulations dedicated to use by children.


Asunto(s)
Ácidos Polimetacrílicos/química , Propranolol/química , Gusto/fisiología , Administración Oral , Química Farmacéutica/métodos , Niño , Composición de Medicamentos/métodos , Liberación de Fármacos/fisiología , Nariz Electrónica , Excipientes/química , Humanos , Microesferas , Saliva Artificial/química , Solubilidad , Comprimidos/química
15.
J Colloid Interface Sci ; 561: 220-230, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31816467

RESUMEN

Textured biomaterials have been extensively used in biomedical engineering to modulate mammalian and bacterial cell adhesion and proliferation, implant integration with human body and infection prevention. However, the tribological implications of texturing under wet physiological conditions have not been well quantified. This study aimed to characterize the tribological properties of micropore-textured polydimethylsiloxane (PDMS) under physiological conditions and investigate the effect of adsorbed lubricious molecules on friction. In this study, untextured and micropore-textured PDMS surfaces were slid against curved smooth glass surfaces under the contact pressures of 10-400 kPa, sliding speeds of 0.1-5 mm/s in aqueous solutions with the viscosity of 1-1000 mPa·s. Reconstituted human whole saliva (RHWS) at pH 7 and porcine gastric mucin (PGM) at both pH 2 and 7 were used as lubricious coatings on PDMS. While the micropore-texturing delayed the transition of lubrication regimes, it increased the coefficient of friction (COF). Although RHWS and PGM coatings decreased the COF significantly, the protein coatings could not help the COF of micropore-textured surfaces getting lower than that of untextured surfaces. The results suggest textured polymeric surfaces could generate larger friction under physiological conditions and lead to a higher chance of inflammation near the implants.


Asunto(s)
Dimetilpolisiloxanos/química , Mucinas Gástricas/química , Saliva Artificial/química , Agua/química , Adsorción , Animales , Humanos , Concentración de Iones de Hidrógeno , Lubrificación , Estrés Mecánico , Propiedades de Superficie , Porcinos , Viscosidad
16.
Talanta ; 208: 120353, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31816720

RESUMEN

A porous and hydrophilic sorbent material was used in an extraction system, assisted by electric fields, for the extraction of cocaine in saliva and subsequent determination by ultra-high-performance liquid chromatography associated with sequential triple quadrupole mass spectrometry (UHPLC-MS/MS). The cellulose-based material was characterized by scanning electron microscopy, infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction. The time and voltage variables applied in the extraction process were investigated through a Doehlert experimental design, and with the best conditions found (35min and 300 V) some validation parameters were evaluated. The established working range was 1-100 µg L-1 (R2 > 0.99), and the detection and quantification limits determined were 0.3 and 0.8 µg L-1, respectively. Recoveries from 80 to 115% and coefficient of variation ≤15 and 16% for intra-day and inter-day assays, respectively, were obtained for sample concentrations of LOQ, 5, 25, and 75 µg L-1, indicating satisfactory accuracy and precision for the proposed method. In addition, the method presented no matrix effect, and the extraction efficiency was between 56 and 70%. The results showed that the material used has adequate physicochemical characteristics and can be applied as a sorbent and electrolyte support in multiphase extractions using electric fields.


Asunto(s)
Celulosa/química , Cromatografía Líquida de Alta Presión/métodos , Cocaína/análisis , Cocaína/aislamiento & purificación , Saliva/metabolismo , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Fenómenos Electromagnéticos , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Saliva/química , Saliva Artificial/química , Saliva Artificial/metabolismo , Extracción en Fase Sólida/instrumentación
17.
Support Care Cancer ; 28(6): 2817-2828, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31732852

RESUMEN

PURPOSE: The aim of this study is to investigate the effect of an edible saliva substitute, oral moisturizing jelly (OMJ), and a topical saliva gel (GC) on dry mouth, swallowing ability, and nutritional status in post-radiotherapy head and neck cancer patients. METHODS: Sixty-two post-radiation head and neck cancer patients with xerostomia completed a blinded randomized controlled trial. They were advised to swallow OMJ (n = 31) or apply GC orally (n = 31) for 2 months. Outcome measures were assessed at baseline, 1, and 2 months, including subjective and objective dry mouth (Challcombe) scores, subjective swallowing problem scores (EAT-10), water swallowing time, clinical nutritional status (PG-SGA), body weight, and dietary intake. RESULTS: After 1 and 2 months of interventions, subjective and objective dry mouth scores, subjective swallowing problem scores, swallowing times, and clinical nutritional status in both groups were significantly improved (p < 0.0001). Compared to GC, OMJ group had higher percent improvement in all outcome measures (p < 0.001) except swallowing time and clinical nutritional status. Interestingly, subjective dry mouth scores were significantly correlated with subjective swallowing problem scores (r = 0.5321, p < 0.0001). CONCLUSIONS: Continuous uses of saliva substitutes (OMJ or GC) for at least a month improved signs and symptoms of dry mouth and enhanced swallowing ability. An edible saliva substitute was superior to a topical saliva gel for alleviating dry mouth and swallow problems. These lead to improved clinical nutritional status. Thus, palliation of dry mouth may be critical to support nutrition of post-radiotherapy head and neck cancer patients. CLINICAL TRIAL REGISTRY: Clinicaltrials.gov NCT03035825.


Asunto(s)
Deglución/fisiología , Neoplasias de Cabeza y Cuello/complicaciones , Neoplasias de Cabeza y Cuello/radioterapia , Estado Nutricional/fisiología , Saliva/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Saliva/citología , Saliva Artificial , Método Simple Ciego , Resultado del Tratamiento , Xerostomía/tratamiento farmacológico
18.
Clin Oral Investig ; 24(6): 2051-2060, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31624923

RESUMEN

OBJECTIVES: To investigate the effect of toothpastes on dentine surface loss and tubule occlusion, and the association of toothpaste-related factors to each of the outcomes. MATERIALS AND METHODS: One hundred and sixty human dentine specimens were randomly distributed into 10 groups, according to different toothpastes. The specimens were submitted to artificial saliva (60 min), citric acid (3 min), and brushing abrasion (25 s; totalizing 2 min in toothpaste slurries). This was repeated five times and two outcome variables were analyzed: dentine surface loss (dSL; µm) and tubule occlusion by measurement of the total area of open tubules (Area-OT; µm2). Data were analyzed with Kruskal-Wallis and Mann-Whitney tests (α = 0.05); bivariate and multivariate regressions were used to model the association of the chemical (pH, concentration of F-, Ca2+, and PO43- and presence of Sn2+) and physical (% weight of solid particles, particle size, and wettability) factors of the toothpastes to both outcome variables. RESULTS: Toothpastes caused different degrees of dSL and did not differ in Area-OT. All chemical and physical factors, except the presence of Sn2+, were associated with dSL (p < 0.001). Area-OT was associated only with the presence of Sn2+ (p = 0.033). CONCLUSION: Greater dSL was associated with lower pH, lower concentration of F-, higher concentration of Ca2+ and PO43-, greater % weight of solid particles, smaller particle size, and lesser wettability, whereas tubule occlusion was associated with the presence of Sn2+. CLINICAL RELEVANCE: Depending on their chemical and physical composition, toothpastes will cause different degrees of dentine tubule occlusion and dentine surface loss. This could, in turn, modulate dentine hypersensitivity.


Asunto(s)
Desensibilizantes Dentinarios , Abrasión de los Dientes , Erosión de los Dientes , Pastas de Dientes , Dentina , Humanos , Saliva Artificial , Abrasión de los Dientes/prevención & control , Erosión de los Dientes/prevención & control , Cepillado Dental
19.
Oper Dent ; 45(2): 173-182, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31373890

RESUMEN

This study compared the viscoelastic properties of restorative and flowable bulk-fill resin-based composites (RBCs) with their conventional counterparts and evaluated the impact of aqueous solutions on viscoelastic properties. The materials examined included three conventional RBCs (Filtek Z350, Tetric N Ceram, and Beautifil II), three restorative bulk-fill RBCs (Filtek Bulk-Fill Restorative, Tetric N Ceram Bulk-Fill, and Beautifil Bulk-Fill Restorative) in addition to three flowable bulk-fill RBCs (Filtek Bulk-Fill Flowable, Tetric N Flow Bulk-Fill, and Beautifil Bulk-Fill Flowable). Beam-shaped specimens (12×2×2 mm) were fabricated using customized stainless-steel molds, finished, and measured. The specimens were randomly divided into four groups and conditioned in air (control), artificial saliva, 0.02 N citric acid, and 50% ethanol-water solution for seven days at 37°C. They were then subjected to dynamic mechanical analysis (n = 10) in flexure mode at 37°C with a frequency of 0.1 to 10 Hz. Storage modulus, loss modulus, and loss tangent data were subjected to statistical analysis using one-way analysis of variance/Tukey post hoc test at a significance level of α = 0.05. Viscoelastic properties of the RBCs were found to be product and conditioning medium dependent. For most RBCs, exposure to aqueous solutions, particularly an ethanol-water solution, degraded viscoelastic properties. With the exception of Filtek Bulk-Fill Restorative, bulk-fill restorative and flowable RBCs generally had significantly lower storage and loss modulus than their conventional counterparts regardless of conditioning medium. Conventional RBCs are thus favored over their bulk-fill counterparts, particularly for high-stress-bearing areas.


Asunto(s)
Resinas Compuestas , Materiales Dentales , Ensayo de Materiales , Saliva Artificial
20.
Ann Rheum Dis ; 79(1): 3-18, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31672775

RESUMEN

The therapeutic management of Sjögren syndrome (SjS) has not changed substantially in recent decades: treatment decisions remain challenging in clinical practice, without a specific therapeutic target beyond the relief of symptoms as the most important goal. In view of this scenario, the European League Against Rheumatism (EULAR) promoted and supported an international collaborative study (EULAR SS Task Force) aimed at developing the first EULAR evidence and consensus-based recommendations for the management of patients with SjS with topical and systemic medications. The aim was to develop a rational therapeutic approach to SjS patients useful for healthcare professionals, physicians undergoing specialist training, medical students, the pharmaceutical industry and drug regulatory organisations following the 2014 EULAR standardised operating procedures. The Task Force (TF) included specialists in rheumatology, internal medicine, oral health, ophthalmology, gynaecology, dermatology and epidemiology, statisticians, general practitioners, nurses and patient representatives from 30 countries of the 5 continents. Evidence was collected from studies including primary SjS patients fulfilling the 2002/2016 criteria; when no evidence was available, evidence from studies including associated SjS or patients fulfilling previous sets of criteria was considered and extrapolated. The TF endorsed the presentation of general principles for the management of patients with SjS as three overarching, general consensus-based recommendations and 12 specific recommendations that form a logical sequence, starting with the management of the central triplet of symptoms (dryness, fatigue and pain) followed by the management of systemic disease. The recommendations address the use of topical oral (saliva substitutes) and ocular (artificial tear drops, topical non-steroidal anti-inflammatory drugs, topical corticosteroids, topical CyA, serum tear drops) therapies, oral muscarinic agonists (pilocarpine, cevimeline), hydroxychloroquine, oral glucocorticoids, synthetic immunosuppressive agents (cyclophosphamide, azathioprine, methotrexate, leflunomide and mycophenolate), and biological therapies (rituximab, abatacept and belimumab). For each recommendation, levels of evidence (mostly modest) and TF agreement (mostly very high) are provided. The 2019 EULAR recommendations are based on the evidence collected in the last 16 years in the management of primary 2002 SjS patients and on discussions between a large and broadly international TF. The recommendations synthesise current thinking on SjS treatment in a set of overarching principles and recommendations. We hope that the current recommendations will be broadly applied in clinical practice and/or serve as a template for national societies to develop local recommendations.


Asunto(s)
Antirreumáticos/uso terapéutico , Glucocorticoides/uso terapéutico , Inmunosupresores/uso terapéutico , Gotas Lubricantes para Ojos/uso terapéutico , Agonistas Muscarínicos/uso terapéutico , Saliva Artificial/uso terapéutico , Síndrome de Sjögren/tratamiento farmacológico , Administración Oftálmica , Corticoesteroides/administración & dosificación , Antiinflamatorios no Esteroideos/administración & dosificación , Ciclosporina/administración & dosificación , Humanos , Hidroxicloroquina/uso terapéutico
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