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1.
J Prosthet Dent ; 2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37643938

RESUMO

Medication-related osteonecrosis of the jaw results in extensive excision and proves challenging to rehabilitate prosthetically. This article describes the prosthodontic rehabilitation of medication-related osteonecrosis of the jaw induced by nintedanib. A custom-made subperiosteal implant was designed to adapt to the bone, remaining after the excision of the jaw necrosis. The implant followed the anatomic contour of the residual bone and was milled in titanium alloy, allowing the rehabilitation of a patient with a fixed dental prosthesis.

2.
Front Mol Biosci ; 10: 1148653, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37065448

RESUMO

The discovery of several functional interactions where one or even both partners remain disordered has demonstrated that specific interactions do not necessarily require well-defined intermolecular interfaces. Here we describe a fuzzy protein-RNA complex formed by the intrinsically unfolded protein PYM and RNA. PYM is a cytosolic protein, which has been reported to bind the exon junction complex (EJC). In the process of oskar mRNA localization in Drosophila melanogaster, removal of the first intron and deposition of the EJC are essential, while PYM is required to recycle the EJC components after localization has been accomplished. Here we demonstrate that the first 160 amino acids of PYM (PYM1-160) are intrinsically disordered. PYM1-160 binds RNA independently of its nucleotide sequence, forming a fuzzy protein-RNA complex that is incompatible with PYM's function as an EJC recycling factor. We propose that the role of RNA binding consists in down-regulating PYM activity by blocking the EJC interaction surface of PYM until localization has been accomplished. We suggest that the largely unstructured character of PYM may act to enable binding to a variety of diverse interaction partners, such as multiple RNA sequences and the EJC proteins Y14 and Mago.

3.
Int J Biol Macromol ; 154: 48-61, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32173434

RESUMO

Present work aimed to develop active packaging films based on chitosan (CS), poly (vinyl alcohol) (PVA) and boswellic acid (BA), and to evaluate the effect of BA on multifunctional properties of CS/PVA (CPBA) active films. Different compositions of active packaging films were prepared by the solvent casting method. The results indicated that incorporation of BA enhanced the ultraviolet blocking, morphology, mechanical properties, water solubility and hydrophilicity of the CPBA active films. Significant improvement in the barriers properties of BA incorporated CPBA active films were observed. The microbiological screening has demonstrated the antimicrobial activity of the films against Escherichia coli, Staphylococcus aureus and Candida albicans. Furthermore, the prepared active films do not deteriorate the thermal properties after incorporation of BA. The overall migration values of the CPBA active films in contact with food simulants were within the permitted limits. The obtained results indicate that the CPBA active film may be a promising material for food packaging applications.


Assuntos
Quitosana/química , Embalagem de Alimentos/métodos , Álcool de Polivinil/química , Triterpenos/química , Fenômenos Mecânicos
4.
Carbohydr Polym ; 236: 116049, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32172863

RESUMO

Ethyl vanillin (EV) incorporated chitosan (CS)/poly(vinyl alcohol)(PVA) blend films of various ratios (1:3, 1:1 and 3:1) were prepared by solvent casting technique. The effect of EV on the mechanical, structural, barrier, optical, food compatibility and antibacterial properties of the CS/PVA films were investigated. Mechanical properties showed that addition of EV increased tensile strength of CPEV-1, CPEV-2 and CPEV-3 films by 39 %, 45 % and 86 %, respectively compared to CS/PVA matrix. The FTIR results confirmed the formation of a Schiff base (CN) and intermolecular hydrogen bonds between CS, PVA, and EV. Incorporation of EV into CS/PVA matrix (i.e. CPEV) showed the marked influence on the water vapor transmission rates (WVTRs) and oxygen transmission rates (OTRs) and exhibited excellent UV barrier capability. Surface morphology of CPEV blend films becomes smooth, homogeneous and dense as visualized through scanning electron microscopy. Contact angle measurements demonstrated the increased hydrophobicity of CPEV blend films with increasing CS content. Strong antibacterial activity was exhibited by CPEV-3 blend films against both E. coli (Escherichia coli) and S. aureus (Staphylococcus aureus) bacteria. The overall migration values of CPEV blend films were 103 times lower than acceptable limits of 10 mg/dm2. Therefore, CPEV blends have good potential to be considered as sources of active films for food packaging applications.

5.
J Indian Prosthodont Soc ; 19(3): 261-265, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31462866

RESUMO

AIM: This study aims to evaluate and compare the effect of plant extract (thyme essential oil solution) and commercially available denture cleanser on the flexural strength and surface roughness of denture base resin. SETTINGS AND DESIGN: Comparative In-vitro study. Chemical denture cleansers play a vital role in maintaining the hygiene and serviceability of the dentures. Bacterial resistance to these chemical agents paved way to plant-extracts as novel denture cleansing agents. However, the effect of these plant-extract denture cleansers on the physical and surface characteristics of denture base resins has not been evaluated. MATERIAL AND METHODS: A total of 90 heat polymerizing denture base material (Trevalon, Dentsply) samples were fabricated and divided into 3 groups with 30 samples each. Samples from each group were immersed in their respective denture cleanser solution (Group A- Distilled water(control); Group B- Fittydent denture cleanser; Group C- Thyme essential oil solution denture cleanser) for a simulated overnight 8hr immersion for 180 days. The samples were evaluated for increase in surface roughness and flexural strength using Tally-surf Surface Profiler and Instron Universal Testing Machine respectively. Results obtained were statistically analyzed using one-way ANOVA. STATISTICAL ANALYSIS USED: Oneway ANOVA , Post hoc Tukey's test. RESULTS: Thyme essential oil solution group showed minimal increase in surface roughness (ΔRa) with values comparable to that of the control group which had the least increase in surface roughness and Fittydent group showed significant increase (P < 0.05) in surface roughness. For flexural strength, statistically significant difference (P < 0.05) was observed among the three groups with Fittydent group showing the highest flexural strength followed by control group and Thyme essential oil solution group. However, the decrease in the flexural strength was not of clinical significance. CONCLUSION: Plant extract - thyme essential oil denture cleanser was superior in preserving the surface roughness of denture base resins compared to commercially available denture cleanser. Clinically significant difference in flexural strength was not observed between the denture cleanser groups.

6.
J Med Chem ; 58(2): 625-39, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25495219

RESUMO

We report on the first chemical syntheses and structure-activity analyses of the cyclic lipopeptide battacin which revealed that conjugation of a shorter fatty acid, 4-methyl-hexanoic acid, and linearization of the peptide sequence improves antibacterial activity and reduces hemolysis of mouse blood cells. This surprising finding of higher potency in linear lipopeptides than their cyclic counterparts is economically beneficial. This novel lipopeptide was membrane lytic and exhibited antibiofilm activity against Pseudomonas aeruginosa, Staphylococcus aureus, and, for the first time, Pseudomonas syringe pv. actinidiae. The peptide was unstructured in aqueous buffer and dimyristoylphosphatidylcholine-polymerized diacetylene vesicles, with 12% helicity induced in 50% v/v of trifluoroethanol. Our results indicate that a well-defined secondary structure is not essential for the observed antibacterial activity of this novel lipopeptide. A truncated pentapeptide conjugated to 4-methyl hexanoic acid, having similar potency against Gram negative and Gram positive pathogens was identified through alanine scanning.


Assuntos
Antibacterianos/síntese química , Biofilmes/efeitos dos fármacos , Lipopeptídeos/síntese química , Animais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Lipopeptídeos/farmacologia , Espectroscopia de Ressonância Magnética , Camundongos , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade
7.
J Indian Prosthodont Soc ; 14(4): 381-92, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25489162

RESUMO

The aim of this study is to assess the efficacy of microwave irradiation in disinfecting gypsum casts and also to compare its efficacy with validated method of chemical disinfection. The present study is an ex vivo study conducted on a sample of five irreversible hydrocolloid impressions in vitro and on ten patients gypsum casts in vivo following standard impression techniques to check the efficacy of microwave oven irradiation and compare its efficacy with standard chemical method of disinfection. Results were analysed using Mann-Whitney test and Wilcoxon signed rank test. Untreated gypsum casts showed cfu/ml counts with a median log value of 6, while microwave-irradiated ones had median cfu/ml counts of 0. Casts poured from chemically disinfected impressions demonstrated cfu/ml counts with a median log value of 5. Microwave irradiation was found to be effective in disinfecting gypsum casts when compared to chemical disinfectant in disinfecting dental impressions.

8.
IET Nanobiotechnol ; 8(4): 184-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25429495

RESUMO

Cobalt ferrite nanoparticles with average sizes of 14, 9 and 6 nm were synthesised by the chemical co-precipitation technique. Average particle sizes were varied by changing the chitosan surfactant to precursor molar ratio in the reaction mixture. Transmission electron microscopy images revealed a faceted and irregular morphology for the as-synthesised nanoparticles. Magnetic measurements revealed a ferromagnetic nature for the 14 and 9 nm particles and a superparamagnetic nature for the 6 nm particles. An increase in saturation magnetisation with increasing particle size was noted. Relaxivity measurements were carried out to determine T2 value as a function of particle size using nuclear magnetic resonance measurements. The relaxivity coefficient increased with decrease in particle size and decrease in the saturation magnetisation value. The observed trend in the change of relaxivity value with particle size was attributed to the faceted nature of as-synthesised nanoparticles. Faceted morphology results in the creation of high gradient of magnetic field in the regions adjacent to the facet edges increasing the relaxivity value. The effect of edges in increasing the relaxivity value increases with decrease in the particle size because of an increase in the total number of edges per particle dispersion.


Assuntos
Cobalto/química , Compostos Férricos/química , Nanopartículas Metálicas/química , Prótons , Quitosana/química , Tamanho da Partícula , Tensoativos/química , Difração de Raios X
9.
J Prosthodont ; 23(5): 367-73, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24393097

RESUMO

PURPOSE: This in vitro study sought to compare the antifungal activity of melaleuca alternifolia oil and fluconazole mixed with a tissue conditioner. MATERIALS AND METHODS: By testing several concentrations of fluconazole and melaleuca oil in Visco-gel, the minimum most effective concentration of each antifungal agent against Candida albicans was determined. Mean inhibition diameter (MID) was used to measure the antifungal activity, and data were analyzed statistically for significance of findings. To determine the minimum most effective concentration of fluconazole, different concentrations of 1%, 3%, 5%, and 10% w/w in Visco-gel were tested on Sabouraud dextrose agar pregrown with C. albicans. MIDs were measured at 24 hours and on day 7, while carrying out the monitoring every day. Similarly, the minimum most effective concentration of melaleuca oil in Visco-gel was found by testing it in several concentrations (1%, 5%, 10%, 20%, 25%, 27.5%, 30%, 35% w/w). Subsequently, the minimum most effective concentration of each antifungal agent was used to compare the antifungal activity against C. albicans over 7 days using the same procedure and using plain tissue conditioner as the control. RESULT: The minimum most effective concentrations of melaleuca oil in Visco-gel and fluconazole in Visco-gel were 30% w/w and 5% w/w, respectively. Thirty percent w/w melaleuca oil was found to be the most effective (p < 0.001) and superior to 5% fluconazole in Visco-gel, as it retained substantial antifungal activity (MID), even on day 7 when fluconazole had lost its antifungal effect completely as evidenced by regrowth of C. albicans by day 7. CONCLUSION: Thirty percent melaleuca oil in tissue-conditioner Visco-gel was superior to 5% fluconazole in Visco-gel as an antifungal agent. Though both showed comparable antifungal activity at 24 hours against C. albicans, fluconazole had completely lost it by day 7, whereas melaleuca oil had substantially retained its antifungal action.


Assuntos
Anti-Infecciosos Locais/farmacologia , Antifúngicos/farmacologia , Materiais Biocompatíveis/química , Fluconazol/farmacologia , Metilmetacrilatos/química , Óleo de Melaleuca/farmacologia , Anti-Infecciosos Locais/administração & dosagem , Antifúngicos/administração & dosagem , Candida albicans/efeitos dos fármacos , Fluconazol/administração & dosagem , Humanos , Teste de Materiais , Melaleuca , Testes de Sensibilidade Microbiana , Micologia/métodos , Óleo de Melaleuca/administração & dosagem , Temperatura , Fatores de Tempo , Condicionamento de Tecido Mole Oral
10.
J Indian Prosthodont Soc ; 14(Suppl 1): 86-92, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26199496

RESUMO

Preparation of porcelain restorations that match the natural dentition has been a subject of great concern for many years. An understanding of the process by which the colour and translucency of fixed restorations are planned and obtained so as to replicate the colour of its adjacent teeth is important for achieving an esthetic restoration. This study was done to study the effect of fabrication procedures such as ceramic thickness and number of firing cycles on the colour of metal ceramic restorations. Metal ceramic samples with three different ceramic thicknesses; 0.5, 1 and 1.5 mm (N = 30, n = 10 per group) were fabricated. A3 shade of [VMK 95, VITA Zahnfabrik, Bad Sackingen, Germany] ceramic was used for the fabrication of samples. Samples were subject to multiple firing cycles and colour was measured after 2nd, 3rd, 4th, 6th, 8th and 10th firing cycle. Colour measurement was done objectively using spectrolino (Gretag Macbeth Inc., Germany) spectrophotometer. 'Repeated measures ANOVA' test was used for doing statistical analysis. No significant change was noticed in any of the four colour parameters between the baseline reading after second firing uptil the tenth firing for any of the three groups with different ceramic thicknesses. There was a consistent rise in L* or lightness of colour as the thickness of ceramic increased. Between group I and group III there was a consistent shift of a* axis towards the blue green side and there was a consistent shift in b* axis towards purple-blue with an increase in ceramic thickness. It was observed that there was a change in ΔE with a change in ceramic thickness. There was a change of about two units between group I and group II and a change of about one unit between group II and group III. Change in ΔE between group I and group III was the most significant, being about three units. It was concluded from the study that multiple firing cycles during fabrication of metal ceramic restorations do not have any effect on colour while colour varies with change in ceramic thickness.

11.
Artigo em Inglês | MEDLINE | ID: mdl-23820713

RESUMO

Patients today demand a youthful, attractive smile with comfortable functional acceptance. The complete oral rehabilitation of patients with a functionally compromised dentition frequently involves a multidisciplinary approach and presents a considerable clinical challenge. To a great extent, proper patient selection and careful interdisciplinary treatment planning, including acknowledgment of the patient's perceived needs, reasons for seeking services, financial ability, and socioeconomic profile, can govern the predictability of successful restorations. This clinical report describes a successful interdisciplinary approach for the management of a severely worn dentition with reduced vertical dimension of occlusion. Treatment modalities included periodontal crown lengthening procedures, endodontic treatment followed by post and core restorations, and prosthetic rehabilitation for severe tooth surface loss and reduced vertical dimension of occlusion comprising metal-ceramic restorations in esthetic zones and full-metal restorations in posterior regions.


Assuntos
Estética Dentária , Reabilitação Bucal/métodos , Equipe de Assistência ao Paciente , Aumento da Coroa Clínica , Coroas , Ligas Dentárias/química , Planejamento de Prótese Dentária , Sensibilidade da Dentina/terapia , Necessidades e Demandas de Serviços de Saúde , Humanos , Registro da Relação Maxilomandibular/métodos , Masculino , Ligas Metalo-Cerâmicas/química , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Planejamento de Assistência ao Paciente , Técnica para Retentor Intrarradicular , Tratamento do Canal Radicular/métodos , Perda de Dente/reabilitação , Desgaste dos Dentes/terapia , Dimensão Vertical
12.
J Prosthodont ; 22(1): 81-4, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23298199

RESUMO

Keloids form as a result of aberrations of physiologic wound healing and may arise following any insult to the deep dermis. By causing pain, pruritus, and contractures, keloids significantly affect the patient's quality of life, both physically and psychologically. Multiple studies have been conducted for decades and have led to a plethora of therapeutic strategies to prevent or attenuate keloid formation, of which no single treatment has proven to be widely effective. Also, there is a dearth of information in the prosthodontic literature regarding appropriate management of such cases, especially when located in cosmetic areas. This clinical report presents an interdisciplinary cooperative approach between maxillofacial prosthetics and dermatology in prophylactic management of postsurgical auricular keloid. A new and an innovatively designed custom prosthesis for the management of the same is presented.


Assuntos
Pavilhão Auricular/patologia , Deformidades Adquiridas da Orelha/prevenção & controle , Queloide/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Próteses e Implantes , Adulto , Pavilhão Auricular/cirurgia , Humanos , Masculino , Pressão
13.
Indian J Dent Res ; 22(2): 359-61, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21891915

RESUMO

A patient presented with an unfavorable distribution of teeth in the arch which precluded treatment with a removable partial denture. The unique pattern of partial edentulism was treated with an overdenture restoration using accesspost system. The final restoration was stable, well retained and esthetic, serving as a conservative approach to root preservation.


Assuntos
Planejamento de Dentadura , Revestimento de Dentadura , Dente Canino/patologia , Dente Suporte , Retenção de Dentadura , Prótese Total Inferior , Humanos , Arcada Parcialmente Edêntula/reabilitação , Masculino , Mandíbula/patologia , Pessoa de Meia-Idade , Dente Molar/patologia , Técnica para Retentor Intrarradicular
14.
J Contemp Dent Pract ; 9(4): 92-8, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18473032

RESUMO

AIM: This clinical report describes the oral rehabilitation of a young female patient diagnosed with the hypocalcified, autosomal recessive type of Amelogenesis imperfecta (AI). A brief discussion on diagnosis of AI is also included. BACKGROUND: AI has been defined as a group of hereditary enamel defects not associated with evidence of systemic disease. It can be characterized by enamel hypoplasia and/or hypomaturation or hypocalcification of the existing teeth. Restoration for patients with this condition should be oriented toward the functional and esthetic rehabilitation and the protection of these teeth. REPORT: A 31-year-old female patient presented with concerns including extreme sensitivity; dissatisfaction with size, shape, and shade of teeth; and poor masticatory efficiency. She was very conscious about the appearance of her teeth and reported that her primary dentition was affected in the same manner. The specific objectives of this treatment were to eliminate tooth sensitivity, enhance esthetics, and restore masticatory function. Treatment included crown lengthening procedures and placement of anterior and posterior metal-ceramic crowns. A 12-month follow-up with clinical and radiographic examinations revealed no evidence of any untoward effects of the treatment on the restored teeth or their supporting structures. SUMMARY: Management of a patient with AI is a challenge for the clinician. The treatment options vary considerably depending on several factors such as the age of the patient, socio-economic status, periodontal condition, loss of tooth structure, severity of the disorder, and, most importantly, the patient's cooperation. The clinician has to consider the long-term prognosis of the treatment outcome. This clinical report describes the fabrication of metal ceramic and all metal crowns for the restoration of severely worn teeth in a patient with AI which requires meticulous maintenance of oral hygiene and patient co-operation.


Assuntos
Amelogênese Imperfeita/diagnóstico , Reabilitação Bucal , Adulto , Amelogênese Imperfeita/classificação , Amelogênese Imperfeita/terapia , Aumento da Coroa Clínica , Coroas , Cárie Dentária/terapia , Porcelana Dentária , Planejamento de Prótese Dentária , Exposição da Polpa Dentária/terapia , Sensibilidade da Dentina/terapia , Estética Dentária , Feminino , Seguimentos , Humanos , Ligas Metalo-Cerâmicas , Planejamento de Assistência ao Paciente , Atrito Dentário/terapia
15.
J Microbiol Methods ; 68(1): 82-7, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16930751

RESUMO

The performance of BBL CHROMagar Listeria chromogenic agar for the detection of Listeria monocytogenes was evaluated for its ability to isolate and identify L. monocytogenes from food and environmental samples. The medium was compared to non-chromogenic selective agars commonly used for Listeria isolation: Oxford, Modified Oxford, and PALCAM. BBL CHROMagar Listeria had a sensitivity of 99% and 100% for the detection of L. monocytogenes from 200 natural and artificially inoculated food samples, respectively, with a colony confirmation rate of 100%. The sensitivity of non-chromogenic selective media for the detection of L. monocytogenes from these same samples was 97-99% with colony confirmation rates of 65-67.5%. From 93 environmental samples, BBL CHROMagar Listeria agar results correlated 100% with a Listeria spp. visual immunoassay (TECRA) performed on these same samples and the USDA-FSIS standard culture method for the isolation of L. monocytogenes. From environmental samples, the L. monocytogenes confirmation rate was 100% for BBL CHROMagar Listeria as compared to 50% for conventional agars tested. On BBL CHROMagar Listeria, L. monocytogenes forms a translucent white precipitation zone (halo) surrounding blue-pigmented colonies of 2-3 mm in diameter, with an entire border. BBL CHROMagar Listeria offers a high degree of specificity for the confirmation of suspect L. monocytogenes colonies, whereas non-chromogenic selective agars evaluated were not differential for L. monocytogenes from other Listeria species.


Assuntos
Técnicas Bacteriológicas/métodos , Microbiologia de Alimentos , Listeria monocytogenes/isolamento & purificação , Ágar , Compostos Cromogênicos/química , Meios de Cultura , Listeriose/microbiologia , Listeriose/prevenção & controle , Sensibilidade e Especificidade
16.
Indian J Dent Res ; 15(2): 62-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15751783

RESUMO

Polymerization shrinkage is one of the major drawbacks of the acrylic resin. The present study was conducted to evaluate the dimensional changes occurring in the dentures, constructed on the casts having different configurations of the palatal vault, during processing and the effect of water sorption on the processed dentures. Eight maxillary edentulous casts having U, F and V configurations of palatal vault were selected and complete dentures were fabricated. Dimensional changes occurring in the processed dentures were studied in different regions during processing as well as after water sorption. It was observed that dimensional changes in frontal and vertical planes were maximum in V shaped palatal vault dentures. Water sorption partly compensated for the dimensional changes that occurred during processing.


Assuntos
Resinas Acrílicas/química , Arco Dental/patologia , Planejamento de Dentadura , Prótese Total Superior , Arcada Edêntula/patologia , Palato/patologia , Absorção , Adsorção , Sulfato de Cálcio/química , Técnica de Moldagem Odontológica/instrumentação , Materiais Dentários/química , Humanos , Imersão , Arcada Edêntula/classificação , Modelos Dentários , Propriedades de Superfície , Água/química
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