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1.
J Prosthet Dent ; 127(5): 767.e1-767.e7, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35282936

RESUMO

STATEMENT OF PROBLEM: Restorations should show low color stainability after clinical and laboratory procedures; however, the impacts of surface treatment and surface region on the color stainability of zirconia restorations are unclear. PURPOSE: The purpose of this in vitro study was to evaluate the effect of surface treatment and surface region on the color stainability of a cemented high-translucency monolithic zirconia ceramic after coffee thermocycling. MATERIAL AND METHODS: Thirty high-translucency Ø10×0.5-mm monolithic zirconia disk specimens were divided into 3 groups based on the surface treatment applied: adjusting (A), polishing (P), and glazing (G). Specimens were cemented to composite resin backings and given 10 000 thermocycles in a coffee solution. CIELab values were measured with a spectrophotometer before and after thermocycling in central and marginal surface regions. ΔE00 values were calculated and compared with perceptibility (ΔE00=0.8) and acceptability (ΔE00=1.8) thresholds to interpret the color changes due to coffee thermocycling. Repeated measures ANOVA and Bonferroni tests were used for data analysis (α=.05). RESULTS: Mean ΔE00 values ranged between 0.72 and 1.26. The surface treatment significantly affected the ΔE00 (P=.005); however, the surface region (P=.499) and the interaction of surface treatment and surface region (P=.998) did not affect the ΔE00. The mean ΔE00 values were less than 0.8 for group G, but greater than 0.8 and less than 1.8 for groups A and P. CONCLUSIONS: Glazing provides the lowest color stainability for cemented high-translucency monolithic zirconia, inducing imperceptible color changes after coffee thermocycling.


Assuntos
Café , Porcelana Dentária , Cerâmica , Cor , Teste de Materiais , Propriedades de Superfície , Zircônio
2.
Int Orthod ; 20(1): 100614, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35153159

RESUMO

INTRODUCTION: Maxillary constriction is a relatively common condition. Various treatment modalities have been proposed for this condition such as rapid maxillary expansion (RME). Although RME can significantly expand the suture in a relatively short period of time, it has a number of drawbacks, mainly a lengthy retention period. The primary objective of this study was to assess the efficacy of the supplementary methods used in conjunction with RME for new bone formation (NBF) at the midpalatal suture (MPS). Relapse, bone healing, and root resorption were also studied as the secondary outcomes. MATERIALS AND METHODS: The PubMed, Embase, and Cochrane library online databases were searched according to the PRISMA-ScR guideline. Animal studies on the effects of non-surgical supplementary methods other than laser therapy on NBF in RME were included and reviewed. RESULT: Thirty-eight articles met the inclusion criteria. The supplementary methods were categorized into 6 groups: hormones, chemical agents, drugs, vitamins, proteins, and some other substances, which could not be assigned to any group. All the aforementioned substances enhanced NBF. Drugs such as bisphosphonates also increased bone resorption. The oestrogen hormone was shown to reduce treatment relapse. Lastly, stem cell application accelerated bone healing at the expanded MPS. CONCLUSION: Administration of hormones, chemical agents, drugs, vitamins, herbs, and proteins may improve the outcomes of RME, shorten the retention period and consequently, reduce relapse in animals. However, the generalizability of these findings is limited due to the insubstantial number of studies published on each substance.


Assuntos
Terapia com Luz de Baixa Intensidade , Técnica de Expansão Palatina , Animais , Humanos , Maxila
3.
Ecotoxicol Environ Saf ; 194: 110353, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32146193

RESUMO

The present study aimed to evaluate the effects of different waterborne sublethal concentrations of Ag-NPs LC50 (96h) on common carp Cyprinus carpio using a multi-biomarker approach. Fish (9.22 ± 0.12 g) were stocked in fiberglass tanks and exposed to concentrations of 0 (control), 12.5%, 25% and 50% of Ag-NPs LC50 (96h) or Ag-NO3 LC50 (96h), as the source of Ag+ ion, for a period of 21 days. At the end of study, tissue Ag contents were significantly (P < 0.05) higher and different in fish exposed to concentrations of 25% and 50% compared to the control. The numbers of RBCs, hematocrit, and MCHC values at these concentrations differed significantly in respect to the control. No significant effects were observed for hemoglobin, MCH, and MCV values. The number of WBCs was significantly higher at concentrations of 12.5% and 25% compared to the control. Meanwhile, the percentage of neutrophils significantly elevated at concentrations of 25% and 50%. Serum total protein at concentration of 50% detected significantly lower than that of 12.5% or the control. The serum albumin and globulin levels significantly declined in Ag-NPs-exposed groups versus the control. The serum ACH50 and total immunoglobulins showed significantly lower values in the treatments of 25% and 50% compared to the control. The serum glucose, cortisol, ALT, and ALP values significantly escalated upon Ag-NPs exposure. The serum SOD and CAT showed enhanced activity in the treatment of 12.5% vice versa significantly diminished at concentrations of 25% and 50% compared to the control. The exposure to the concentrations of 25% and 50% significantly dwindled the lysozyme activity and total immunoglobulin levels in skin mucus. In conclusion, sublethal concentrations of Ag-NPs LC50 (96h) impaired fish health status at higher concentrations and 12.5% of Ag-NPs LC50 (96h) was presumably safe for common carp aquaculture.


Assuntos
Carpas/fisiologia , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Animais , Antioxidantes/metabolismo , Aquicultura , Bioacumulação , Carpas/metabolismo , Eritrócitos/metabolismo , Hematócrito , Hematologia , Hemoglobinas/metabolismo , Dose Letal Mediana
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