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1.
Biomedicines ; 11(9)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37760874

RESUMO

The aim of this study was to establish the cut-off value for the thyroglobulin (Tg) concentration in washout fluid from fine needle aspiration biopsy (FNA-Tg) in the detection of cervical lymph node metastases of differentiated thyroid cancer (DTC). We evaluated the validity and clinical utility of fine needle aspiration biopsy cytology (FNAB-C), FNA-Tg, and the combined method in detecting DTC recurrences. The study included 82 patients after the total thyroidectomy and elective and, in some cases, also selective cervical lymphadenectomy. The majority of patients also underwent subsequent 131I ablative therapy. The patients presented with 1-6 enlarged and/or ultrasonographically suspicious cervical lymph nodes. One to four aspirates of each lymph node were taken, with a total of 297 samples. An FNA-Tg of 4.34 ng/mL was established as the cut-off value for detecting cervical lymph node DTC metastases for the IRMA Brahms DYNO test, Tg-S. FNAB-C is highly specific (91-99%) but not sensitive enough (53-69%) to be used as a standalone method in the detection of cervical lymph node metastases. FNA-Tg is more sensitive (91%), but caution should be taken when selecting patients for surgery with an FNA-Tg higher than the established cut-off value but lower than the serum Tg concentration. To select patients for lymphadenectomy, we recommend using the combined method (FNAB-C and FNA-Tg) with a sensitivity of 96% and specificity of up to 97%. More than one sample should be taken with each fine needle aspiration biopsy (FNAB) to obtain a representative set of samples.

2.
Materials (Basel) ; 16(10)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37241426

RESUMO

The purpose of this in vitro study was to determine the effect of airborne-particle abrasion process parameters on the strength of the Ni-Cr alloy-ceramic bond. One hundred and forty-four Ni-Cr disks were airborne-particle abraded with 50, 110 and 250 µm Al2O3 at a pressure of 400 and 600 kPa. After treatment, the specimens were bonded to dental ceramics by firing. The strength of the metal-ceramic bond was determined using the shear strength test. The results were analyzed with three-way analysis of variance (ANOVA) and the Tukey honest significant difference (HSD) test (α = 0.05). The examination also considered the thermal loads (5000 cycles, 5-55 °C) to which the metal-ceramic joint is subjected during exploitation. There is a close correlation between the strength of the Ni-Cr alloy-dental ceramic joint and the alloy roughness parameters after abrasive blasting: Rpk (reduced peak height), Rsm (the mean spacing of irregularities), Rsk (skewness of the profile) and RPc (peak density). The highest strength of the Ni-Cr alloy surface bonding with dental ceramics under operating conditions is provided by abrasive blasting under 600 kPa pressure with 110 µm Al2O3 particles (p < 0.05). Both the abrasive blasting pressure and the particle size of the Al2O3 abrasive significantly affect the joint's strength (p < 0.05). The most optimal blasting parameters are 600 kPa pressure with 110 µm Al2O3 particles (p < 0.05). They allow the highest bond strength between the Ni-Cr alloy and dental ceramics to be achieved.

3.
Materials (Basel) ; 15(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35160910

RESUMO

The SiC abrasive blasting parameters are vital in ensuring a suitable bond between dental ceramics and the Ni-Cr alloy. The purpose of this in vitro test was to examine the strength of the joint between the Ni-Cr alloy and fused dental ceramics for SiC abrasive blasting at a specific pressure (400, 600 kPa) and particle size (50, 110, 250 µm) in order to determine the optimal treatment parameters. The test also accounted for thermal loads (5000 cycles, 5-55 °C) to which the metal-ceramic joint is subjected during use. One hundred and forty-four Ni-Cr cylinders were divided into six groups (n = 12) and subjected to the airborne-particle abrasion with SiC with various pressure and grit size parameters. After treatment, the specimens were rinsed, dried, fused to dental ceramics, and examined for their shear strength using the Zwick/Roell Z020 machine. The results were statistically analysed using the ANOVA analysis of variance (α = 0.05). The highest metal-ceramic joint strength was obtained for abrasive blasting with 110 and 250 µm SiC grit at a pressure of 400 kPa. This relationship was also observed after the joint was subjected to thermal loads (5000 thermocycles). Additionally, thermal loads did not significantly reduce the joint's strength compared with non-loaded joints. For small SiC abrasive grit sizes (50 µm) under pressure 400 kPa, the treatment pressure had a significant effect on the strength of the joint (p < 0.05). For larger particle sizes, the pressure had no effect. After abrasive blasting using SiC, the Ni-Cr metal-ceramic joint retained its properties, even under thermal load, ensuring the joint properties' stability during use.

4.
Materials (Basel) ; 14(8)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923646

RESUMO

An adequate surface is essential in ensuring a solid bond between the metal and dental ceramics for metal framework wettability. This work is aimed at investigating the effect of variable abrasive blasting parameters on Ni-Cr alloy surface's ability to be wetted with liquid ceramics at elevated temperatures. One-hundred and sixty-eight samples were divided into 12 groups (n = 14), which were sandblasted using variable parameters: type of abrasive (Al2O3 and SiC), the grain size of the abrasive (50, 110, and 250 µm), and processing pressure (400 and 600 kPa). After treatment, the samples were cleaned in an ultrasonic cleaner and dried under compressed air. Dental ceramics were applied to the prepared surfaces via drops, and the wettability was tested in a vacuum oven at temperatures in the range of 850-1000 °C. The results were statistically analyzed using ANOVA (α = 0.05). For all surfaces, the contact angles were less than 90° at temperatures below 875 °C. For Al2O3, the best wettability was observed for the smallest particles and, for SiC, the largest particles. The ability to wet the surface of a Ni-Cr alloy is related to its sandblasting properties, such as roughness or the percentage of embedded abrasive particles. It should not be the only factor determining the selection of abrasive blasting parameters when creating a prosthetic restoration.

5.
Materials (Basel) ; 13(24)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371248

RESUMO

Abrasive blasting is a process widely used in dentistry. One of the uses is the development of metal surfaces for connections with ceramics in fixed prosthetic restorations. The purpose of this paper was to check how the rough surface profile (width, height, and depth on unevenness) impacts the surface's condition, like its wettability and percentage of stuck abrasives. The Ni-Cr alloy surface was abrasive blasted by silicon carbide with the various pressure parameters (0.2, 0.4, and 0.6 MPa) and abrasive particle sizes (50, 110, and 250 µm). Cleaned surfaces were examined for roughness, wettability, and percentage of stuck abrasive particles on the surface. The surface after abrasive blasting using 110 µm of abrasive size and 0.4 MPa pressure has the best wettability results. The width of unevenness may cause it. When the unevenness has too small or too large width and depth, the fluids may not cover the entire cavities because of locking the air. The surface condition of dental alloys directly affects metal-ceramic connection strength. The knowledge about the impact of the abrasive blasting parameters on the bond strength will allow one to create durable dental restorations.

6.
Dermatol Ther ; 33(6): e14391, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33034937

RESUMO

Tranexamic acid (TA) has anti-hemorrhagic effects; however, oral administration has been found to decrease hyperpigmentation. The aim of the work was to compare the effects of treatment with 5% tranexamic acid in combination with corundum microdermabrasion on skin pigmentation, redness, pH, transepidermal water loss (TEWL), sebum level and hydration of back surface and dorsal surface of the hand skin. Six treatments were performed every week on the back surface and both dorsal surfaces of the hands of 12 subjects. The entire back/both hands were treated with 5% tranexamic acid at pH 2.38; left side of the back or left hand were also subjected to corundum microdermabrasion. Skin parameters were measured using the Courage & Khazaka 580 Multi Probe Adapter. Clinical photos were taken using the Fotomedicus system. Significant differences between treatment methods were observed for melanin, erythema and pH. In addition, the two methods differed significantly with regard to the amount of sebum, TEWL and the level of moisture in the skin. Both methods gave similar acidic pH. Summing up tranexamic acid causes a significant reduction in epidermal melanogenesis, has a significant impact on the level of skin hydration, lipids of the epidermis and maintaining the proper TEWL. TA has a significant effect on reducing skin redness.


Assuntos
Ácido Tranexâmico , Óxido de Alumínio , Humanos , Concentração de Íons de Hidrogênio , Lipídeos , Fenômenos Fisiológicos da Pele
7.
J Cosmet Dermatol ; 18(5): 1529-1538, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30628153

RESUMO

BACKGROUND: Hybrid manicure is now a popular method of nail care and nail art, which is associated with its durability. Unfortunately, it has an adverse effect on pH, TOWL and overall nail plates condition and has not been investigated in detail so far. AIMS: The aim of this study was to compare the pH and TOWL of the hand nails after using different primers. The effect of application time, breaks between applications and the method of curing and removal on those parameters and overall nail plates condition were evaluated. PATIENTS/METHODS: An evaluation survey was conducted among 116 women. pH and TOWL measurements of the nail plate in 35 women were taken using the Courage & Khazaka. Clinical photos were made using the Fotomedicus system. RESULTS: The measured pH values of the nail plate in the test group with gel polish hybrid on the nails were from 5.50 to 6.65, while after removal of the gel polish hybrid, the values ranged from 5.63 to 6.68. TOWL of the nail plate covered with gel polish hybrid ranged from 2.9 to 33.2 g/m2 /h, whereas after removal of hybrids-from 1.9 to 45.7 g/m2 /h. CONCLUSION: Different forms of acid-free primers maintain a lower pH of the nail plate covered with a gel polish hybrid, while the acidic primer maintains higher values of the nail plate pH. The significant decrease in the nail plate TOWL following the application of gel polish hybrid indicates a reduced loss of water from the surface of the nail to the atmosphere.

8.
J Prosthet Dent ; 120(3): 470-475, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29627218

RESUMO

STATEMENT OF PROBLEM: Airborne-particle abrasion of titanium is a clinically accepted method of surface preparation. As a side effect of airborne-particle abrasion, particles of the abrasive material get embedded into the surface. How particle presence or removal from the titanium surface affects the strength of the titanium-ceramic bond is unclear. PURPOSE: The purpose of this in vitro study was to determine the effect of removing Al2O3 particles embedded into the surface by means of chemical surface treatment on the strength of the titanium-ceramic bond. MATERIAL AND METHODS: Titanium (TritanCpTi 1, Dentaurum, 99.5% Ti) disks were airborne-particle abraded with 110 µm Al2O3 at a pressure of 0.4 MPa and an angle of approximately 45 degrees. The surface was etched chemically using 1 of 8 reagents, and the veneering ceramic applied and fired. The strength of the metal-ceramic bond was determined using the shear strength test. Further, the effect of thermal fatigue on the bond strength was evaluated. The results were analyzed with 2-way ANOVA and the Tukey honest significant difference (HSD) test (α=.05). Fractographic investigations and microscopic tests were also performed to determine the quality of the titanium-ceramic bond. RESULTS: Effective etching of the titanium surface and removal of Al2O3 particles included a 30% water solution of HNO3 + 3% HF, a mixture of HNO3 + HF + glycerin, a 4% solution of HF in H2O2, and a 4% solution of HF in H2O. A statistically significant difference (of about 50%) in bond strength was found between the groups subjected to chemical etching and the control group (P<.05). Additionally, a statistically significant difference (about 25%) was found after thermocycling (P<.05). CONCLUSIONS: Removing the Al2O3 particles embedded into the titanium surface after airborne-particle abrasion lowers the strength of the titanium-ceramic bond (P<.05). Thermocycling also weakens the strength of the titanium-ceramic bond, regardless of the surface preparation (P<.05).


Assuntos
Cerâmica/uso terapêutico , Colagem Dentária , Ligas Metalo-Cerâmicas/uso terapêutico , Titânio , Abrasão Dental por Ar , Óxido de Alumínio , Prótese Dentária , Humanos , Propriedades de Superfície
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