ABSTRACT
Objective: The aim of this study was to compare the bond strength of High-Translucency zirconia (HT) and lithium disilicate dental ceramics, under different surface treatments. Material And Methods: For this, ceramics were divided into groups: Control Group (C) (n = 5), lithium disilicate sheets, conditioned with 10% hydrofluoric acid, followed by application of 37% phosphoric acid, silane and universal adhesive application; Group HTAI (n = 5), HT zirconia sheets were blasted with silica oxide, followed by the application of universal adhesive; Group HTPAI (n = 5), HT zirconia sheets were blasted with silica oxide, followed by the application of non-thermal plasma and universal adhesive and the HTP Group (n = 5), HT zirconia received only the application of non-thermal argon plasma. Subsequently, the specimens of each group were subjected to a cementation process with resin cement, obtaining cylinders. After 24 h of storage, in distilled water, at 37°C, the specimens were subjected to a mechanical micro-shear test. The data obtained were submitted to ANOVA One-way followed by the Tukey test (5%). Results: The HTP Group was excluded from the statistical analysis, as adhesions failed within the storage period. In addition, it was not possible to verify a statistical difference between the control group C and the experimental groups HTAI and HTPAI. Conclusion: The results showed that the applicability of high translucency zirconia can potentially be compared to the lithium disilicate bond strength, when submitted to the same surface treatments, except for the plasma application, which alone was not effective (AU)
Objetivo: O objetivo deste estudo foi comparar a resistência adesiva das cerâmicas dentárias de zircônia de alta translucidez e dissilicato de lítio. Materiais e Métodos: Para isso, cerâmicas foram divididas em grupos: Grupo Controle (C) (n = 5), lâminas de dissilicato de lítio, condicionadas com ácido fluorídrico 10%, seguido de aplicação do ácido fosfórico 37%, aplicação de silano e aplicação do adesivo universal; Grupo HTAI (n = 5), lâminas de zircônia HT foram submetidas ao jateamento com óxido de sílica, seguido da aplicação do adesivo universal; Grupo HTPAI (n = 5), lâminas de zircônia HT foram submetidas ao jateamento com óxido de sílica, seguido da aplicação do plasma não térmico e do adesivo universal e o Grupo HTP (n = 5), lâminas de zircônia HT receberam apenas a aplicação do plasma não térmico de argônio. Posteriormente, os espécimes de cada grupo foram submetidos a um processo de cimentação com cimento resinoso, obtendo-se cilindros. Após 24h, de armazenamento em água destilada a 37°C, os espécimes foram submetidos a ensaio mecânico de microcisalhamento. Os dados obtidos foram submetidos à ANOVA 1-fator seguido pelo teste de Tukey (5%). Resultados: O Grupo HTP foi descartado da análise estatística, pois as adesões falharam dentro do período de armazenamento. Além disso, não foi possível verificar diferença estatística entre o grupo controle C e os experimentais HTAI e HTPAI. Conclusão: Os resultados mostraram que a aplicabilidade das zircônias de alta translucidez pode potencialmente ser comparada à resistência adesiva da cerâmica de dissilicato de lítio, quando submetidas aos mesmos tratamentos de superfície, com exceção da aplicação de plasma, que isoladamente não foi efetiva (AU)
Subject(s)
Metal Ceramic Alloys , Dentin-Bonding Agents , Resin Cements , Dental CementsABSTRACT
PURPOSE: This study evaluated the effect of nonthermal plasma treatment on the bond strength of autopolymerizing relining resin to the injection molded thermoplastic denture base resins (TDBRs) with different surface treatments. MATERIALS AND METHODS: Acrylic Resin (Acrytone), Polyester (Estheshot-Bright), Polyamide (Valplast) and Polypropylene (Weldenz) were subjected to various surface treatments: No treatment, Nonthermal plasma, Sandblasting, Sandblasting and nonthermal plasma. Specimens were bonded using an autopolymerizing relining resin. Shear bond strength was tested using universal testing machine with crosshead speed of 1 mm/min. Statistical analysis by two-way analysis of variance with Tukey's test post hoc was used. RESULTS: Acrytone showed significantly higher shear bond strength value among other TDBR group while Weldenz had the lowest. The sandblasting and nonthermal plasma condition had significantly higher shear bond strength value in all of the resin groups (P < .05). CONCLUSION: The use of nonthermal plasma treatment showed limited effect on the shear bond strength between TDBRs and relining resin, and combination of nonthermal plasma and sandblasting improved the shear bond strength between TDBR and reline material.
Subject(s)
Denture Bases , Dentures , Fungi , Nylons , Plasma , Polyesters , PolypropylenesABSTRACT
Objective To investigate the biological effects of nonthermal plasma (NTP) combined with X-ray irradiation on human hepatocellular carcinoma in nude mice.Methods By subcutaneous inoculation, tumor models of human hepatocellular carcinoma HepG2 in nude mice were established, and these mice were divided into control group, NTP treatment group, X-ray irradiation group, combined treatment group.The changes of tumor microenvironment were observed using hematoxylin-eosin (HE) staining.The terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) was used to determine the level of neuronal apoptosis in tumor tissues.The expression of metal matrix proteinase-2 (MMP-2) was detected by immunohistochemical assay.Transmission electron microscope was used to observe cell structure changes.Results The final tumor volumes of control group, NTP treatment group, X-ray irradiation group, combined treatment group were (543.96±108.45), (436.54±65.49), (351.66±56.68), (281.97±35.60)mm3, with a statistically significant difference (F=9.63, P=0.01), and the difference between X-ray radiation group and the combination treatment group was significant (P=0.05).HE staining showed that there was a larger area of necrosis in the combined treatment group compared with the other groups.TUNEL showed that the apoptotic indexes were (0.95±0.13)%, (5.82±0.26)%, (7.53±0.43)%, (11.07±0.35)% respectively, with a statistically significant difference (F=547.76, P=0.00), and the difference between X-ray radiation group and the combination treatment group was statistically significant (P=0.00).The immune scores of each group were 12, 9, 9, 2.Electron microscopic observation showed that there were more apoptotic bodies in the combined treatment group than those in the other groups, accompanied by mitochondrial edema.Conclusion NTP and X-ray irradiation therapy in the treatment of human hepatocellular carcinoma in nude mice model has a synergistic effect.Probably, it can be a new type of treatment in curing cancers.
ABSTRACT
PURPOSE: To determine the effects of nonthermal plasma (NTP) induced by helium (He) alone or He plus oxygen (O2) on the generation of reactive oxygen species (ROS) and cell death in anaplastic thyroid cancer cells. MATERIALS AND METHODS: NTP was generated in He alone or He plus O2 blowing through a nozzle by applying a high alternating current voltage to the discharge electrodes. Optical emission spectroscopy was used to identify various excited plasma species. The apoptotic effect of NTP on the anaplastic thyroid cancer cell lines, such as HTH83, U-HTH 7, and SW1763, was verified with annexin V/propidium staining and TUNEL assay. ROS formation after NTP treatment was identified with fluorescence-activated cell sorting with DCFDA staining. The mitogen-activated protein kinase pathways and caspase cascade were investigated to evaluate the molecular mechanism involved and cellular targets of plasma. RESULTS: NTP induced significant apoptosis in all three cancer cell lines. The plasma using He and O2 generated more O2-related species, and increased apoptosis and intracellular ROS formation compared with the plasma using He alone. NTP treatment of SW1763 increased the expression of phosphor-JNK, phosphor-p38, and caspase-3, but not phosphor-ERK. Apoptosis of SW1763 as well as expressions of elevated phosphor-JNK, phosphor-p38, and caspase-3 induced by NTP were effectively inhibited by intracellular ROS scavengers. CONCLUSION: NTP using He plus O2 induced significant apoptosis in anaplastic cancer cell lines through intracellular ROS formation. This may represent a new promising treatment modality for this highly lethal disease.