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1.
Scand J Rheumatol ; 52(5): 530-538, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36503416

RESUMO

OBJECTIVE: To compare the demographic, clinical, and radiological features of patients with axial spondyloarthritis (axSpA) accompanying familial Mediterranean fever (FMF) to patients with each condition alone. METHOD: Hacettepe University Hospital database was screened regarding ICD-10 codes for FMF (E85.0) and axSpA (M45). The diagnosis of FMF was confirmed by Tel-Hashomer criteria, and axSpA by the presence of sacroiliitis according to the modified New York criteria or active sacroiliitis on magnetic resonance imaging. As control groups, 136 gender-matched, consequent FMF patients without axSpA and 102 consequent axSpA patients without FMF previously treated with any biological agents were included in the analysis. RESULTS: In patients with FMF + axSpA compared to the axSpA group, age at axSpA symptom onset and age at diagnosis were lower [median with interquartile range (IQR): 21 (17-30) vs 27 (21-37), p < 0.001; 23 (21-38) vs 32 (24-43) years, p = 0.001], moderate to severe hip disease and total hip replacement were more prevalent (23.4% vs 4.7%, p < 0.001; 11.2% vs 2.8%, p = 0.016). In patients with FMF + axSpA compared to the FMF group, age at FMF symptom onset and age at diagnosis were higher [13 (6-30) vs 11 (5-18), p = 0.057; 23 (13-33) vs 18 (10-31) years, p = 0.033] and amyloidosis was more prevalent (6.6% vs 2.2%, p = 0.076). Although the M694V variant (in one or two alleles) was more prevalent in the FMF + axSpA group, the difference was not statistically significant. CONCLUSION: In patients with FMF + axSpA, the age of onset of axSpA was significantly earlier, moderate to severe hip involvement and amyloidosis were more common than in patients with each condition alone.


Assuntos
Amiloidose , Espondiloartrite Axial , Febre Familiar do Mediterrâneo , Sacroileíte , Humanos , Febre Familiar do Mediterrâneo/complicações , Febre Familiar do Mediterrâneo/epidemiologia , Febre Familiar do Mediterrâneo/diagnóstico , Sacroileíte/diagnóstico por imagem , Sacroileíte/epidemiologia , Amiloidose/complicações , Demografia
2.
Folia Morphol (Warsz) ; 81(3): 679-684, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34308540

RESUMO

BACKGROUND: The parotid gland in sheep ends freely in front of the masseter muscle, and paracondylary section of occipital bone and extends deep until pterygoid extends of sphenoid bone and hyoid bone. The structure of salivary glands in mammals has been thoroughly studied using histological and sialographic method. This study aimed to reveal the detailed anatomic features and race-specific differences of the canal system of the parotid glands in Akkaraman sheep by using the corrosion cast technique. MATERIALS AND METHODS: Thirteen sheep parotid glands from 7 Akkaraman sheep were used in this study. Parotid glands were removed from their places with ducts. Measurements were made with a calliper from back to front, top to bottom and inside to outside. After dissection of the parotid glands, their volumes were measured according to the 'Archimedes principle'. Also, 13 sheep parotid glands were examined using the polyester resin method. RESULTS: In the present study, our average metric results were: length of parotid duct was 10.92 ± 1.027 cm, length of parotid gland was 5.87 ± 1.04 cm, volume of parotid gland was 12.50 ± 2.48 cm³, thickness of parotid gland was 0.75 ± 0.36 cm and width of parotid gland was 4.07 ± 0.43 cm. The average weight of the parotid gland of Akkaraman sheep was identified as 25.3 g. Accessory parotid gland was not encountered in the current study. CONCLUSIONS: It was observed that polyester entered into the parotid duct and filled up until the acinus and made both acinus and secretory ducts well-examined in this study. It was also observed that the parotid gland consisted of lobes and lobules. The average number of lobes was 12. The number of lobules in a lobe varied between 3 and 16, each lobe consisted of an average of 9 lobules. It was found that each lobe has its own lobar duct.


Assuntos
Glândula Parótida , Glândulas Salivares , Animais , Ovinos
3.
J Obstet Gynaecol ; 35(1): 9-12, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24999531

RESUMO

Intrauterine growth restriction (IUGR) is one of the most common problems in obstetrics. Ischaemia-modified albumin (IMA), a product deriving from albumin as a result of the modification by oxidative free radicals in response to hypoxia, was previously used as a marker of ischaemia in acute coronary syndrome. We performed this study to determine whether umbilical venous IMA levels are associated with IUGR. A total of 40 pregnancies with IUGR were compared with 40 of normal fetal development. Blood samples were obtained from the umbilical vein after delivery. IMA levels in the IUGR group were higher than in the control group (78.74 ± 6.87 vs 74.43 ± 7.84 U/ml, respectively, p = 0.011). An elevated IMA level was associated with IUGR (OR: 1.079, 95% CI: 1.000-1.163, p = 0.049). We suggest that IMA, which was formerly proved to arise in ischaemic conditions, may also be a valuable marker in perinatal hypoxia and IUGR detection.


Assuntos
Retardo do Crescimento Fetal/sangue , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Estudos de Viabilidade , Feminino , Humanos , Gravidez , Albumina Sérica , Albumina Sérica Humana , Veias Umbilicais , Adulto Jovem
4.
Eur J Clin Microbiol Infect Dis ; 33(6): 871-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24452966

RESUMO

The causative pathogens in diabetic foot infections differ in studies of European compared with Asian populations. The purpose of this study was to determine the causative microorganisms and their antibiotic sensitivity patterns in diabetic patients with a foot infection in Turkey, a country at the crossroads of these two continents. We performed a comprehensive literature search to identify all published studies pertaining to DFIs in patients cared for in Turkey. To assess changes in causative organisms and their antibiotic sensitivity patterns over time, we compared the results of just the most recent 5 years (2007-2011) with those of the past 20-years (1989-2011). We identified 31 studies meeting our inclusion criteria. Overall, these studies reported 2,097 patients, from whom 1,974 microorganisms were isolated. The total percentage of gram-negative and gram-positive aerobic bacteria were similar in each of the assessed periods. The rate of isolation of Staphylococcus aureus during the entire period, compared with just the past 5 years, was 23.8% and 19.1%, respectively, while the rate of methicillin-resistant S. aureus was 7.8% and 5.7%, respectively. The isolation rate of Pseudomonas aeruginosa was 13.7% for the entire period and 14.9% for the past 5 years. While linezolid, vancomycin and teicoplanin were the most active agents against gram-positive microorganisms, imipenem and cefoperazone-sulbactam were the most active against gram-negative microorganisms. This systematic review demonstrated few substantial changes in diabetic foot microbiology over the past 20 years. The data may help develop and update local clinical guidelines regarding antibiotic therapy for diabetic foot infections in Turkey. Further studies, especially with optimal culture methods, would be useful to validate these findings.


Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Pé Diabético/complicações , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Prevalência , Turquia/epidemiologia
7.
Thorac Cardiovasc Surg ; 56(6): 359-62, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18704859

RESUMO

BACKGROUND: Proliferating scar tissue is an important problem after tracheal surgery. Hyperbaric oxygen (HBO) provides good support to the poorly perfused tissues. We aimed to evaluate the early effects of HBO therapy on tracheal healing after tracheal resection. METHODS: A total of 15 Wistar rats were divided into two groups and two tracheal rings of each rat were resected. A control group received no therapy while the other group was treated with HBO. At the end of the study or when a rat died, a histopathological examination was performed to assess neovascularization, necrosis and epithelization. RESULTS: HBO treatment caused better epithelization and inflammation scores compared to the control group. In the HBO group the intraluminal purulent exudates were limited (P=0.001). Healing of the damaged mucosal epithelium was better in the HBO group (P=0.031). In the HBO-treated group, neovascularization also started earlier than in the group without HBO. CONCLUSION: Our short-term observation results demonstrate that HBO treatment increases tracheal healing and decreases the complication ratios. HBO may be preferred as a supportive treatment modality during the healing period after tracheal surgery.


Assuntos
Cicatriz/prevenção & controle , Oxigenoterapia Hiperbárica , Traqueia/cirurgia , Traqueotomia/efeitos adversos , Cicatrização , Anastomose Cirúrgica/efeitos adversos , Animais , Cicatriz/etiologia , Cicatriz/fisiopatologia , Modelos Animais de Doenças , Feminino , Neovascularização Fisiológica , Ratos , Ratos Wistar , Traqueia/patologia , Traqueia/fisiopatologia
8.
J Int Med Res ; 36(2): 222-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18380930

RESUMO

Inside attendants are medical staff who accompany patients during hyperbaric oxygen treatments. Dysbaric osteonecrosis (DON) is a well-known consequence of hyperbaric exposure. The aim of this study was to evaluate DON in inside attendants using magnetic resonance imaging (MRI). The bilateral shoulder, hip and knee joints of 12 inside attendants (four men, eight women; mean age 29 years; age range 22 - 36 years) were investigated. The mean +/- SD duration of employment as an inside attendant was 3.8 +/- 3.0 years (range 1 - 9 years) and the mean +/- SD number of hyperbaric exposures was 198 +/- 267 (median 96; range 30 - 950). None of the inside attendants had a history of decompression sickness. The MRIs of the attendants did not reveal bone lesions consistent with DON. This study failed to find an increased risk for DON in inside attendants. Additional multicentre epidemiological studies are warranted to investigate the occupational safety of inside attendants.


Assuntos
Oxigenoterapia Hiperbárica/efeitos adversos , Imageamento por Ressonância Magnética , Doenças Profissionais/diagnóstico , Doenças Profissionais/etiologia , Osteonecrose/diagnóstico , Osteonecrose/etiologia , Recursos Humanos em Hospital , Adulto , Animais , Doença da Descompressão/diagnóstico , Doença da Descompressão/etiologia , Feminino , Humanos , Oxigenoterapia Hiperbárica/instrumentação , Masculino , Fatores de Risco
10.
Physiol Res ; 56(3): 369-373, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-16792474

RESUMO

The aim of the present study was to evaluate the efficiency of combination of hyperbaric oxygen (HBO) and an antioxidant on permanent focal cerebral ischemia. Male Wistar rats underwent permanent middle cerebral artery occlusion (MCAO). Then, animals were randomly assigned to one of four groups: the control group (n=9) received no treatment, HBO group (n=9) was treated for 90 min at 2.5 absolute atmosphere for 3 days, the U-74389G group (n=8) received single U-74389G injection (3 mg/kg), the HBO + U-74389G group (n=8) received both HBO and U-74389G treatments. Treatments were initiated within the first 10 min after MCAO. After 3 days, the infarct volumes in rat brains were measured. The infarct ratios were 25.6+/-6.5 % for the control group, 21.9+/-6.4 % for the HBO group, 15.7+/-5.7 % for U-74389G group and 12.5+/-3.8 % for HBO + U74389G group. The infarct volumes were significantly reduced in rats treated with U-74389G (p<0.05) and combination therapy (p<0.05). HBO failed to reduce infarct volume significantly. We concluded that 1) U-74389G is more beneficial than HBO on permanent MCAO in rats, and 2) a combined therapy failed to significantly improve infarct volume more than either single treatment.


Assuntos
Antioxidantes/uso terapêutico , Isquemia Encefálica/terapia , Oxigenoterapia Hiperbárica , Pregnatrienos/uso terapêutico , Animais , Isquemia Encefálica/tratamento farmacológico , Terapia Combinada , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/terapia , Masculino , Ratos , Ratos Wistar
11.
Undersea Hyperb Med ; 33(1): 1-4, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16602250

RESUMO

The effects of hyperoxia on intraocular pressure (IOP) have been studied in experiments on human beings and animals. The changes occurring in IOP in patients during routine HBO2 therapy are unknown. In this study we investigated IOP changes arising during the HBO2 therapy at 2.5 ATA. Fifty-six patients receiving HBO2 therapy for various reasons were included in the study. Bilateral IOPs of patients measured with the Tono-pen XL (Medtronic, Solan, USA) tonometer before, during and after HBO2 therapy. Average IOPs were 14.85 +/- 3.17 mmHg (range, 10-24), 13.00 +/- 2.97 mmHg (range, 9-21) and 14.74 +/- 3.12 mmHg (range, 10-22), respectively. IOP was reduced significantly during HBO2 therapy and returned its pre- HBO2 levels after therapy. Our data indicated a statistically significant decrease in IOPs during therapy at 2.5 ATA. This decrease was of minor physiological significance in these patients whose baseline IOP values were within the normal range.


Assuntos
Oxigenoterapia Hiperbárica , Pressão Intraocular/fisiologia , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pressão Parcial
12.
J Oral Rehabil ; 30(11): 1142-8, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14641682

RESUMO

This study focused on some mechanical properties such as the transverse strength, the maximal deflection, and the modulus of elasticity of resin reinforced with two different types of agents-treated and with untreated glass fibre, and without fibre. A Teflon mould was used to prepare six groups of specimens. Two different types of chemical modification agents, hydroxyethyl-methacrylate (HEMA)-monomer and air atmosphere were applied to create hydrophilic surfaces on the glass fibres. The flow rate was kept at two different levels, 25 and 60 mL min-1. The discharge powers of the surface treatment process were 15 or 20 W. The fibres were exposed to glow discharge conditions for the periods of 10 or 15 min. Without fibre specimens were the control group. The provisional resin was same in all groups. All the specimens were subjected to transverse testing with a cross-head speed of 5 mm min-1. The three-point load test was used to record the load of the fracture for each specimens. The Kruskal-Wallis analysis of variance was used to compare the transverse strength, the maximal deflection and the modulus of elasticity. The differences in the transverse strength and the maximal deflection between the six groups were found statistically significant but the modulus of elasticity was not statistically significant. The transverse strength of HEMA-monomer (group A) was shown the highest value (66.3 MPa). For without-fibre group, the value was 52.9 MPa. This difference was statistically significant when the Mann-Whitney U-test was used for comparing. Repairing or remaking provisional restorations can be a time-consuming endeavour. The added strength of the polymethyl methacrylate with the fibre can reduce clinical failures of provisional fixed partial dentures. The surface treatment process was increased the transverse strength and the maximal deflection. The clinical implication of chemical modification agents-coated fibres is reduced incidence of fixed provisional restoration failure.


Assuntos
Prótese Parcial Fixa , Vidro/química , Metacrilatos/química , Resinas Acrílicas/química , Ar , Falha de Restauração Dentária , Análise do Estresse Dentário/métodos , Elasticidade , Humanos , Teste de Materiais/métodos , Microscopia Eletrônica de Varredura , Estresse Mecânico , Propriedades de Superfície
13.
J Biomater Appl ; 15(4): 351-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11336388

RESUMO

Fracture resistance of prosthesis is an important clinical concern. This property is directly related to transverse strength. Strengthening of prostheses may result from reinforcement with various fiber types. This study evaluated the effect of fiber type on the transverse strength of a commercially available autopolymerizing resin that is used for repairing prosthesis. The resin was reinforced with woven form, chopped form and longitudinal form, and no reinforcement was used. Uniform samples were made from autopolymerizing resin. In total, twenty-four bar-shaped specimens (60 x 10 x 4 mm) were reinforced with glass fibers. Nine specimens were prepared without fiber. A three-point loading test was used to measure transverse strength, maximal deflection, and modulus of elasticity. The Kruskal-Wallis analysis of variance was used to examine differences between the four groups. Although the results of the analysis between these groups showed no statistical significances, the transverse strength, maximal deflection and modulus of elasticity increased more with fiber than without the fiber group. This finding may be of clinical significance. Because the addition of fiber reinforcement enhanced the physical properties of the processed material, specially woven form glass fiber was superior to the other forms.


Assuntos
Materiais Biocompatíveis , Vidro , Próteses e Implantes , Polimetil Metacrilato
14.
J Comput Assist Tomogr ; 25(3): 458-65, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11351199

RESUMO

PURPOSE: The purpose of this work was to determine the efficacy of MR angiography (MRA) in the detection and characterization of occlusive disease in the vertebrobasilar system. METHOD: We retrospectively reviewed the posterior circulation registry of our institution to select 42 consecutive patients with posterior circulation ischemic symptoms who underwent both MRA and angiography. The extracranial vertebral arteries (ECVAs) were examined by two-dimensional time-of-flight MRA above the C6 level, and the intracranial vertebral arteries (ICVAs) and basilar arteries (BAs) were examined by three-dimensional time-of-flight MRA. Sixty-two ECVAs, 63 ICVAs, and 39 BAs were examined by the readers. RESULTS: Occlusive disease was seen on angiography in 22 of the 42 patients. The sensitivity and specificity values for detection of lesions in 12 ECVA, 19 ICVA, and 12 BA abnormalities were as follows: ECVA, 92 and 96% for Reader A and 100 and 90% for Reader B; ICVA, 84 and 93% for Reader A and 74 and 82% for Reader B; and BA, 100 and 88% for Reader A and 100 and 78% for Reader B. For ICVA, the sensitivity of MRA was less than that of angiography because of lesions missed by the readers at the junctional area of the extra-and intracranial MRA. MRA accurately characterized 9 of the 12 (75%) ECVA, 10 of the 19 (43%) ICVA, and 11 of the 12 (92%) BA lesions. CONCLUSION: MRA is an effective method for detection of occlusive lesions in the ECVAs and BAs. Clinically important lesions can be missed by MRA in the ICVA. MRA is more accurate in characterization of occlusive lesions in BAs than in ECVAs or ICVAs.


Assuntos
Arteriopatias Oclusivas/diagnóstico , Artéria Basilar , Angiografia por Ressonância Magnética , Artéria Vertebral , Idoso , Idoso de 80 Anos ou mais , Angiografia , Angiografia Digital , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
15.
J Biomater Appl ; 16(2): 149-56, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11794724

RESUMO

This study focused on some mechanical properties such as the transverse strength, maximal deflection and modulus of elasticity of a resin reinforced with untreated, chopped form glass fibers at different concentrations. A Teflon mould was used to prepare four groups of specimens. The specimens were prepared with different concentrations of the glass fiber to the mass of the powder/liquid mix (0.5, 1, 1.5%), and a mix without fiber was used as the control group. All the specimens were subjected to transverse testing with a cross-head speed of 5 mm/min. The load to fracture for each specimen with the maximum deflection at the point of loading in a three-point load test was recorded. The transverse strength of 0.5% fiber concentration was 54.45 MPa. The lowest value was 49.67 MPa for the 1% fiber concentration. The highest mean strength was for the specimens reinforced with 0.5% glass fiber. This mean was higher than for the mean of the control "without fiber" specimens. The specimens demonstrated an insignificant decrease in the transverse strength and the maximum deflection when the fiber concentration was increased. The inclusion of 1% glass fiber reduced the transverse strength, although the result was not statistically significant.


Assuntos
Reparação em Dentadura/métodos , Dentaduras , Vidro , Resinas Vegetais , Elasticidade , Teste de Materiais , Microscopia Eletrônica de Varredura
16.
Int Dent J ; 50(2): 93-7, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10945188

RESUMO

AIM: To test the effect of reinforcement qualities of glass fibre in the repair of acrylic fractures. METHODS: Four types of heat-curing acrylic resin test specimens were fabricated. The bottom and sides of the specimens were placed in stone to form a repair template. Lines were drawn 3.5 mm on each side of the centring mark. The 45 degree-bevel joint margins were cut at these lines to simulate fracture and the centre section was discarded. A 1 mm gap was created between the margins before repair with autopolymerising acrylic resin with and without glass fibre. OUTCOME MEASURES: A three-point loading test was used to measure transverse strength, deflection and the modulus of elasticity of repaired acrylic resin joints. RESULTS: The transverse strength of acrylic resins was increased with fibres. CONCLUSION: Glass fibre-reinforcement significantly increased resistance to deflection and increased the modulus of elasticity.


Assuntos
Resinas Acrílicas/química , Colagem Dentária , Reparação em Dentadura/métodos , Distribuição de Qui-Quadrado , Análise do Estresse Dentário , Elasticidade , Vidro , Humanos , Teste de Materiais , Maleabilidade , Estatísticas não Paramétricas , Resistência à Tração
17.
J Oral Rehabil ; 26(10): 821-9, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10564440

RESUMO

The aim of this study was to measure the colour stability and viscoelastic properties of three commercially available soft lining materials in vitro, by exposing them to 3% erythrosine, tartrazine and sunset yellow solutions. The colour changes were determined using a computer controlled spectrophotometer. The colour change of three soft lining materials--Molloplast B, Flexor and Coe Super Soft--were determined after 1, 3 and 6 months storage in three different food colorant solutions. The colour changes of Molloplast B was not noticeable. Only the initial colour value of Flexor was significantly different from the other time interval colour measurements. On the other hand, the colour difference of Coe Super Soft was found to be significantly different at all comparative time interval measurements (P<0.05). According to Shore A hardness values, Molloplast B had an initial hardness of 44 in all three solutions, and there was a slight increase after 6 months. Flexor had an initial hardness of 39, at the end of 6 months the hardness changed a little. Coe Super Soft was fairly hard after processing and Shore A hardness was initially 89 which increased to 95 later on. According to these results, only the hardness values of Coe Super Soft showed a statistically significant difference when compared using Wilcoxon signed rank test at the P<0.05 level. As a conclusion, silicon type soft lining material seems to be more resistant to colour change and hardness than the acrylic type soft liners.


Assuntos
Resinas Acrílicas/química , Materiais Dentários/química , Reembasadores de Dentadura , Dimetilpolisiloxanos/química , Corantes de Alimentos/farmacologia , Ácidos Polimetacrílicos/química , Elastômeros de Silicone/química , Cor , Interações Medicamentosas , Elasticidade , Dureza , Testes de Dureza/instrumentação , Teste de Materiais/métodos , Teste de Materiais/estatística & dados numéricos , Soluções , Espectrofotometria Ultravioleta , Estatísticas não Paramétricas , Fatores de Tempo , Viscosidade
18.
J Prosthet Dent ; 81(5): 616-20, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10220668

RESUMO

STATEMENT OF PROBLEM: Fracture strength of denture base resins is of great concern, and many approaches have been used to strengthen acrylic resin dentures. PURPOSE: This study measured the effect of 5 fiber strengtheners on the fracture resistance of denture base acrylic resin material. Impact strength, transverse strength, deflection, and elasticity modulus values of a heat-polymerized denture base resin (Trevalon), reinforced with glass, carbon, thin Kevlar, thick Kevlar, and polyethylene fibers in woven form were studied. MATERIAL AND METHODS: One hundred acrylic resin test specimens reinforced with woven fibers were fabricated. The control group consisted of 20 specimens with no fiber reinforcement. For the impact strength test, a Charpy-type impact tester was used. Transverse strength was assessed with a 3-point bending test by using a screw-driven mechanical testing machine. Ten specimens were used for each test. RESULTS: The highest impact test values were produced by polyethylene-reinforced group, and the lowest values were obtained from specimens containing no fibers. There were significant differences among the test groups, but no significant differences in transverse strength were found. The lowest transverse strength values were obtained for specimens strengthened with polyethylene fibers, which also insignificantly decreased transverse strength of the acrylic resin. CONCLUSION: The impact strength of denture base acrylic resins was increased with fibers in woven form. Tested fibers did not have a significant effect on the transverse strengths.


Assuntos
Bases de Dentadura , Polimetil Metacrilato/química , Análise de Variância , Carbono/química , Intervalos de Confiança , Análise do Estresse Dentário/instrumentação , Elasticidade , Vidro/química , Humanos , Teste de Materiais , Metilmetacrilatos/química , Polietilenos/química , Polímeros/química , Estresse Mecânico , Propriedades de Superfície
19.
J Prosthet Dent ; 81(4): 375-9, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10095204

RESUMO

STATEMENT OF PROBLEM: Three commonly used artificial dyes in food technology are erythrosine, tartrazine, and sunset yellow. PURPOSE: The color stability of 5 commercially available denture base acrylic resins (QC-20, Meliodent, Trevalon, Trevalon High, and Lucitone) was studied in vitro. METHODS: The specimens were exposed to 3% erythrosine, tartrazine, and sunset yellow solutions at 23 degrees C +/- 1 degrees C. Color changes were determined with a computer-controlled spectrophotometer. Five specimens from each material were processed, and initial color measurements were made after 1, 3, and 6 months of exposure to the staining solutions. Finally, the color stability was quantitatively measured again, and color differences (DeltaE) were calculated. RESULTS: For the observations made in 1, 3, and 6 months intervals, the specimens that exhibited the least color change were in the sunset yellow solution. The greatest color changes observed according to the National Bureau of Standards unit system were Lucitone (2.71) in erythrosine solution, Lucitone (2.54), QC-20 (1.71) in tartrazine solution, and QC-20 (1.66) in sunset yellow solution. The changes in the other acrylic resins in the 3 solutions were slight and at trace level. CONCLUSIONS: All materials tested were acceptable from the standpoint of color stability for long-term exposure to these food colorants.


Assuntos
Resinas Acrílicas/química , Bases de Dentadura , Corantes de Alimentos/farmacologia , Pigmentação em Prótese , Cor , Bases de Dentadura/estatística & dados numéricos , Interações Medicamentosas , Estabilidade de Medicamentos , Teste de Materiais/métodos , Teste de Materiais/estatística & dados numéricos , Pigmentação em Prótese/estatística & dados numéricos , Estatísticas não Paramétricas , Fatores de Tempo
20.
Artigo em Inglês | MEDLINE | ID: mdl-9638700

RESUMO

The purpose of this study was to compare the effectiveness of splint therapy on the electromyographic activity of masticatory muscles (anterior temporalis and masseter) before and after the application of a muscle relaxation splint. Electromyography recordings from the masseter and anterior temporalis muscles were analyzed quantitatively during maximal biting in the intercuspal position both before and after treatment without a splint. Fourteen patients whose chief complaint was masticatory muscle pain were selected for the study. After the initial evaluations muscle relaxation splints were applied, and the patients were instructed to use the splints for 6 weeks. Surface electromyographic recordings were taken from each patient before the beginning of clinical therapy and after 6 weeks of wearing the splints. The data obtained were analyzed through paired sample t tests and Wilcoxon's signed rank tests. The results of the study were as follows: (1) the electromyographic activity of the two muscles during maximal biting was not markedly changed after the muscle relaxation splint was used; and (2) the changes observed in electromyographic activity of the involved and noninvolved sides were insignificant as well.


Assuntos
Dor Facial/terapia , Músculo Masseter/fisiopatologia , Placas Oclusais , Terapia de Relaxamento/instrumentação , Músculo Temporal/fisiopatologia , Adulto , Força de Mordida , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Modalidades de Fisioterapia/instrumentação , Amplitude de Movimento Articular , Estatísticas não Paramétricas , Resultado do Tratamento
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