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1.
Cytokine ; 180: 156659, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38781872

RESUMO

PURPOSE: Breast cancer (BC) is the most recognized malignancy in females globally and is heterogeneous in its clinical manifestation, among which the triple-negative (TNBC) subtype is the most aggressive. This study examines the associations between IL-1ß polymorphisms and BC and TNBC susceptibility. METHODS: Genotyping ofIL-1ßrs1143627, rs1799916, and rs16944 polymorphisms was done in 488 women with BC (130 TNBC, 358 non-TNBC) and 476 cancer-free control women using real-time PCR genotyping. RESULTS: The minor allele and genotype frequencies of rs1799916, rs1143627, and rs16944 significantly differed among BC cases and controls and remained after correcting key covariates. On the other hand, minor allele and genotype frequencies of only rs16944 significantly differed between TNBC and non-TNBC cases. Spearman correlation analyses demonstrated that all three variants correlated positively with menopausal status and Her2 status but negatively with menarche, breastfeeding, and cancer type. In addition, rs1143627 and rs16944 correlated positively with HR and ER, while rs1799916 correlated positively with Ki67 status. The three variants correlated negatively with menarche, breastfeeding, and cancer type in non-TNBC cases but positively with histological grading in non-TNBC and Her2 in TNBC cases. A positive correlation was noted between rs1143627 and rs1799916 and age (<40 years) and between rs1799916 and rs16944 with menopausal status. We confirmed that GCG haplotype imparted BC susceptibility, while TCA and TTG haplotypes were protective of BC. Among TNBC cases, only GCG and TCA haplotypes remained protective of TNBC after adjustment. CONCLUSIONS: Our study highlights the association between IL-1ßgenetic polymorphisms and BC and TNBC susceptibility, suggesting these variants' diagnostic/prognostic capacity in BC patients.


Assuntos
Predisposição Genética para Doença , Interleucina-1beta , Polimorfismo de Nucleotídeo Único , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/genética , Feminino , Interleucina-1beta/genética , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Predisposição Genética para Doença/genética , Adulto , Frequência do Gene/genética , Estudos de Casos e Controles , Alelos , Genótipo , Idoso , Fatores de Risco
2.
Photobiomodul Photomed Laser Surg ; 41(10): 576-582, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37870415

RESUMO

Objective: Assessment of post surface conditioners [sulfuric acid (SA), Rose Bengal (RB), and sandblasting (SB)] and different luting cements [methyl methacrylate (MMA)-based cement and composite-based cement] on pushout bond strength (PBS) of poly-ether ether-ketone (PEEK) post bonded to canal dentin. Materials and methods: Endodontic treatment was performed on 120 single-rooted human premolar teeth. The preparation of the post space was performed and 4 mm of gutta-percha was retained in the apical region of the root. One hundred and twenty PEEK posts were fabricated from a PEEK blank utilizing a Computer aided design-Computer aided manufacture (CAD-CAM) system. The PEEK posts were allocated randomly into four groups based on post surface conditioning (n = 30). Group A: SA, Group B: RB, Group C: SB, and Group D: No conditioning (NC). Each group was further divided into two subgroups based on the luting cement used for bonding (n = 15). Group A1, B1, C1, and D1 specimens were cemented using composite-based resin cement. However, Group A2, B2, C2, and D2 posts were luted with MMA-based resin cement. PBS assessment using a universal testing machine was performed. Failure modes were analyzed under a stereomicroscope. The data relating to the effects of surface treatment and luting types of cement were analyzed using one-way analysis of variance (ANOVA) and Tukey's post hoc test (p = 0.05). Results: Coronal section of Group B2: RB+Super-Bond C&B [9.61 ± 0.75 megapascals (MPa)] displayed the highest bond scores of PEEK after root dentin. Whereas it was also discovered that Group D1: NC+Panavia®V5 (2.05 ± 0.72 MPa) presented the lowest PBS scores. Intergroup comparison analysis revealed that Group A2: SA+Super-Bond C&B and Group B2: RB+Super-Bond C&B displayed no significant difference in their bond scores. Conclusions: RB and SA possess the potential to be used as a PEEK post conditioner. MMA-based cement displayed better performance than composite-based cement.


Assuntos
Fotoquimioterapia , Cimentos de Resina , Humanos , Resinas Compostas/química , Dentina , Éter , Cetonas , Metacrilatos/química , Metilmetacrilato , Cimentos de Resina/química , Rosa Bengala
3.
Am J Reprod Immunol ; 90(1): e13731, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37382171

RESUMO

BACKGROUND: A role for resistin in the pathogenesis of polycystic ovarian syndrome (PCOS) and related features were described for various ethnicities. As its expression is partly inherited, a role for RETN polymorphisms in regulating resistin levels and PCOS risk was shown, but with varied results. AIM: To investigate the association of rs34124816 (-537A>C), rs1862513 (-420C>G), rs3219175 (-358G>A), rs3745367 (+299G>A), rs3745369 (+1263G>C), and rs1423096 (+4965C>T) RETN SNPs with PCOS. METHODS: Study subjects included 583 women with PCOS, and 713 eumenorrheic women serving as controls. Genotyping was done by real-time PCR. RESULTS: Higher minor allele frequency (MAF) of rs34124816, rs3219175, and rs3745369, and lower MAF of rs1862513 and rs1423096 were seen in PCOS cases. Reduced PCOS risk was found with rs3745367 minor-allele homozygotes and rs1423096 minor-allele homozygotes, while increased risk was linked with rs3745367 heterozygotes, and with rs3745369 heterozygotes and minor-allele homozygotes. While it did not reach statistical significance, serum resistin levels were elevated in PCOS cases than in control women and major-allele homozygotes of rs34124816 and rs1862513, and in rs1423096 minor-allele-containing carriers. Carriage of rs34124816 correlated positively with age and LH, whereas rs1862513 positively and rs3745367 negatively correlated with fasting glucose. Six-locus (rs34124816-rs1862513-rs3219175-rs3745367-rs3745369-rs1423096) haplotype analysis demonstrated a significant reduction in AGGGGG and a marked increase in AGGGCG haplotypes between cases and controls, thus assigning PCOS protective and susceptible nature to these haplotypes, respectively. CONCLUSIONS: This study is the first to document the contribution of rs34124816 and rs1423096 RETN variants to the risk of PCOS. The varied association of RETN gene variants with PCOS suggests an ethnic contribution of RETN association with PCOS.


Assuntos
Síndrome do Ovário Policístico , Resistina , Feminino , Humanos , Alelos , Estudos de Casos e Controles , Síndrome do Ovário Policístico/genética , Polimorfismo de Nucleotídeo Único , Resistina/genética
4.
Photodiagnosis Photodyn Ther ; 42: 103619, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37209762

RESUMO

AIM: To assess and compare the antimicrobial efficacy of disinfectants on lithium disilicate ceramic (LDC) used in dental applications and shear bond strength (SBS) of LDC after using different conditioners hydrofluoric acid (HF), self-etching ceramic primers (SECP) and Neodymium-doped yttrium orthovanadate (Nd: YVO4). MATERIALS AND METHODS: One hundred and twenty LDC discs were fabricated by auto-polymerizing acrylic resin using the lost wax technique. S. aureus, S. mutans, and C. albican were inoculated on thirty discs (n = 30 each). Each group was further divided into three subgroups based on different disinfecting agents used (n = 30) Group 1: Garlic extract, Group 2: Rose Bengal (RB) activated by PDT, and Group 3: Sodium hypochlorite (NaOCl). An assessment of the survival rate of microorganisms was performed. The remaining thirty samples were surface treated using three different LDC surface conditioners (n = 10) Group 1: HF + Silane (S), group 2: SECP, and Group 3: Nd: YVO4 laser+S. SBS and failure mode analysis were performed using a universal testing machine and stereomicroscope at 40x magnification, The statistical analysis was conducted using one-way ANOVA and Post Hoc Tukey test. RESULTS: Garlic extract, RB, and 2% NaOCl sample displayed comparable outcomes of antimicrobial potency against C. albicans, S aureus, and S. mutans (p > 0.05). Furthermore, SBS analysis showed HF+S, SECP, and Nd: YVO4+S exhibited comparable outcomes of bond strength (p > 0.05). CONCLUSION: Garlic extract and Rose bengal activated by PDT can be contemplated as alternatives to the chemical agent NaOCl used for LDC disinfection. Similarly, SECP and Nd: YVO4 possess the potential to be used for the surface conditioning of LDC to improve the bond integrity with resin cement.


Assuntos
Desinfetantes , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Propriedades de Superfície , Descontaminação , Rosa Bengala , Staphylococcus aureus , Fotoquimioterapia/métodos , Cerâmica/química , Ácido Fluorídrico/química , Teste de Materiais
5.
Microsc Res Tech ; 86(7): 762-772, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37129273

RESUMO

The aim was to formulate an experimental adhesive (EA) and added nanoparticles (NPs) of beta-tricalcium phosphate (ß-TCP) to see the impact on pushout bond strength (PBS) and other mechanical properties. Three adhesives were prepared, including EA (control, without ß-TCP NPs), 2.5%-ß-TCP NPs containing adhesive (2.5%-NPA), and 5% ß-TCP NPs containing adhesive (5%-NPA). For the characterization of the NPs, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy was accomplished. For the adhesive's characterization, rheological assessment, and degree of conversion (DC) analysis were performed. PBS of these adhesives against resin fiber post to root dentin, interfacial failure categories, and resin dentin interface analysis were also assessed. The ß-TCP NPs were seen as agglomerated asymmetrical particles on SEM. These NPs were composed primarily of calcium (Ca), and phosphorus (P). Rheological evaluation of the adhesive's showed a drop in the viscosity of all adhesives at greater angular frequencies. The greatest DC was detected for the EA group (67.54 ± 7.9) followed by 2.5%-NPA group (45.32 ± 5.1), whereas the lowest DC values were seen for the 5%-NPA group (38.97 ± 6.5). Concerning PBS, the 2.5%-NPA revealed the highest values at the coronal (12.81 ± 3.0) and middle (8.50 ± 2.3) sections, whereas, for the apical section, the highest PBS values were seen for the 5%-NPA (4.9 ± 1.6). Most of the failures for all adhesive groups were seen at the adhesive-dentin interface (cohesive type failures) for all root segments (coronal, middle, and apical). The resin-dentin interface analysis verified hybrid layer and resin tag formation for all adhesives, but the presence of dispersed ß-TCP NPs was only seen in the two NP-reinforced adhesives. The adding of ß-TCP NPs in the adhesive could be beneficial as it could improve its PBS. Suitable rheological properties and dentin interaction were also observed for NP-reinforced adhesives. A reduced DC was seen for both ß-TCP NP-containing adhesives as compared to the EA. RESEARCH HIGHLIGHTS: Experimental adhesives were reinforced with beta-tricalcium phosphate (ß-TCP) nanocrystals. The ß-TCP NPs were seen as agglomerated asymmetrical particles on SEM. These NPs were composed primarily of calcium (Ca), and phosphorus (P). ß-TCP adhesives demonstrated superior pushout bond strength and a drop in the adhesive viscosity at greater angular frequencies compared to control adhesive. The greatest DC was detected for the EA group followed by 2.5%- ß-TCP group, whereas the lowest DC values were for the 5%- ß-TCP group.


Assuntos
Cálcio , Colagem Dentária , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Adesivos Dentinários/química , Dentina , Cimentos de Resina/química , Teste de Materiais , Resinas Vegetais , Adesivos , Resistência à Tração
6.
Photodiagnosis Photodyn Ther ; 42: 103589, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37142074

RESUMO

AIMS: Assessment of the efficacy of final root canal irrigants Sapindus mukorossi (SM), Potassium titanyl phosphate laser (KTPL), and Fotoenticine (FTC) on the push-out bond strength (PBS) of zirconia post. MATERIALS AND METHODS: The root canal procedure was initiated using the 10 K file and the working length was determined on single-rooted human premolar teeth after decoration. The canals were then enlarged using ProTaper universal system and filled using single cone gutta-percha (GP) and AH Plus resin sealer. Post space was prepared by removing 10 mm of GP from the canal. All the teeth were then allocated into four groups based on the final irrigating regime used (n = 10) Group 1: 5.25% NaOCl+17% EDTA, Group 2: 5.25% NaOCl + KTPL, Group 3: 5.25% NaOCl + FTC and Group 4: 5.25% NaOCl+ SM. Zirconia posts were cemented in the canal space. The specimens were sectioned and implanted in auto-polymerizing acrylic resin. A universal testing machine and stereomicroscope at 40x magnification were used for PBS and failure mode analysis. ANOVA and Tukey post hoc test were used to make group comparisons(p = 0.05). RESULTS: Group 4 (5.25% NaOCl+ SM) coronal section displayed the highest PBS (9.29±0.24 MPa). However, group 3 (5.25% NaOCl+ FTC) apical third (4.08±0.14 MPa) showed the lowest bond values. Group 2 (5.25% NaOCl+ KTP laser) and Group 3 at all three-thirds unveiled no significant difference in PBS(p>0.05). However, Group 1 (5.25% NaOCl+17%EDTA) and Group 4 displayed comparable outcomes of bond strength(p>0.05) CONCLUSION: Sapindus mukorossi has the ability to be used as a final root canal irrigant alternative to EDTA. However, future studies are still required to conclude the outcomes of existing research.


Assuntos
Lasers de Estado Sólido , Fotoquimioterapia , Materiais Restauradores do Canal Radicular , Sapindus , Humanos , Resinas Epóxi , Lasers de Estado Sólido/uso terapêutico , Ácido Edético , Dentina , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes , Guta-Percha , Preparo de Canal Radicular/métodos , Irrigantes do Canal Radicular , Teste de Materiais , Cavidade Pulpar
7.
Photodiagnosis Photodyn Ther ; 42: 103546, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37001713

RESUMO

AIMS: To estimate the effect of contemporary final root canal irrigants (Ozonated water (OW), Chitosan, and Fotoenticine (FTC) on the bond scores of glass fiber post (GFP) and Martens hardness (MH) of root dentin. MATERIALS AND METHODS: Sixty extracted human premolars having a single straight canal that ends in a closed apex were included. Specimens were de-crowned till the cementoenamel junction preserving 12 mm of root length and were mounted vertically. Canal therapy was performed using a crown-down approach. Obturation was performed followed by post-space preparation. Samples were allocated into 4 groups based on chemical irrigations and photosensitizers used(n = 15). Group 1 (5.25% NaOCl + 17% EDTA), group 2 (5.25% NaOCl + FTC), group 3 (5.25% NaOCl + Chitosan), group 4 (5.25% NaOCl + OW). The ultra microhardness tester was put under a load of 5 mN at a speed of 1.5 mN/s for 1 s to assess the MH. The fiber post was luted with dual-cure cement and slices of 1 mm were prepared from each third of the tooth. PBS and failure mode analysis were performed using a universal testing machine (UTM) and stereomicroscope respectively. ANOVA and Tukey multiple comparisons t-tests for assessment of PBS and MH p > 0.05 RESULTS: Group 1 (5.25% NaOCl + 17% EDTA) exhibited the highest MH (0.19 ± 0.04 GPa). Whereas, group 2 (5.25% NaOCl + FTC) displayed the lowest MH (0.011 ± 0.14 GPa). The highest PBS was exhibited by the coronal third of group 1 (5.25% NaOCl + 17% EDTA) (7.11 ± 0.81 MPa). The apical section of group 3 specimens (5.25% NaOCl + Chitosan) (2.33 ± 0.26 MPa) unveiled the lowest PBS. Intergroup comparison analysis revealed that group 2 and group 3 displayed comparable outcomes of PBS. Group 1 and Group 4 also demonstrated no significant difference in the bond scores in all three sections. CONCLUSION: OW as a final irrigant can be used as an alternative to EDTA as it improves the bond strength with minimum impact on marten hardness.


Assuntos
Quitosana , Ozônio , Fotoquimioterapia , Humanos , Dureza , Preparo de Canal Radicular , Quitosana/farmacologia , Ozônio/farmacologia , Ácido Edético/farmacologia , Dentina , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Irrigantes do Canal Radicular/farmacologia , Irrigantes do Canal Radicular/uso terapêutico , Teste de Materiais , Cavidade Pulpar
8.
Reprod Biomed Online ; 45(5): 995-1005, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35933319

RESUMO

RESEARCH QUESTION: What role do ADIPOQ variants play in controlling adiponectin concentrations and altered risk of polycystic ovary syndrome (PCOS)? DESIGN: Study subjects comprised 583 women with PCOS and 713 age-matched controls. Genotyping of rs182052, rs822393, rs822396, rs7649121, rs3774271, rs266729, rs3774261 and rs6773957 ADIPOQ polymorphisms was done by real-time polymerase chain reaction (PCR). RESULTS: Of the 16 ADIPOQ variants, the minor allele frequencies of rs182052, rs822393, rs822396, rs7649121, rs3774261 and rs6773957 were significantly different between PCOS cases and controls. Significant differences in rs266729 (P = 0.02), rs822396 (P = 0.02), rs3774261 (P < 0.001) and rs6773957 (P < 0.001) genotypes were also noted between PCOS cases and controls. Reduced PCOS risk was found with heterozygous rs266729, while increased risk was linked to heterozygous rs822396 and homozygous minor allele rs3774361, and in heterozygous and homozygous minor allele rs6773957 genotype carriers. Haplotype analysis identified two blocks based on linkage disequilibrium pattern; alleles coded as '1' (major) and '2' (minor). Within Block 1 (rs4632532, rs16861194, rs266729, rs182052, rs16861209, rs822393, rs822395, rs822396, rs7649121), haplotypes 111111111 and 212211221 were positively, while haplotypes 212212112 and 212211211 were negatively associated with PCOS. Within Block 2 (rs2241766, rs1501299, rs2241767, rs3774261, rs6773957, rs1063539) haplotypes 111221 and 112221 were positively, while haplotype 111111 was negatively associated with PCOS. CONCLUSIONS: This is the first study to confirm the association of rs182052, rs822393, rs7649121 and rs6773957 ADIPOQ variants with altered risk of PCOS. The varied association of ADIPOQ variants with PCOS in relation to earlier reports indicate there is an ethnic contribution to ADIPOQ association with PCOS.


Assuntos
Síndrome do Ovário Policístico , Feminino , Humanos , Haplótipos , Síndrome do Ovário Policístico/genética , Estudos de Casos e Controles , Polimorfismo de Nucleotídeo Único , Frequência do Gene , Genótipo , Predisposição Genética para Doença , Adiponectina/genética
9.
PLoS One ; 16(5): e0248455, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33970944

RESUMO

The Immune System-Released Activating Agent (ISRAA) was discovered as a novel molecule that functions as a mediator between the nervous and immune systems in response to a nervous stimulus following an immune challenge. This research investigated the role of ISRAA) in promoting the ontogeny of the mouse brain astrocytes. Astrocyte cultures were prepared from two-month-old BALB/c mice. Recombinant ISRAA protein was used to stimulate astrocyte cultures. Immunohistochemistry and ELISA were utilized to measure ISRAA and IFN-γ levels, IFN-γR expression and STAT1 nuclear translocation. MTT-assay was used to evaluate cellular survival and proliferation. To assess astrocyte cell lysates and tyrosine-phosphorylated proteins, SDS-PAGE and western blot were used. ISRAA was highly expressed in mouse embryonic astrocytes, depending on cell age. Astrocytes aged seven days (E7) showed increased proliferation and diminished differentiation, while 21-day-old (E21) astrocytes depicted reversed effects. IFN-γ was involved in the ISRAA action as ISRAA induced IFN-γ in both age groups, but only E21 astrocytes expressed IFN-γR. ISRAA stimulation of E21 resulted in tyrosine phosphorylation of numerous cellular proteins and the nuclear translocation of STAT1, a signalling pathway utilized by IFN-γ. The results suggest that ISRAA is involved in mouse brain development through the cytokine network involving IFN-γ.


Assuntos
Astrócitos/metabolismo , Encéfalo/citologia , Linfocinas/metabolismo , Animais , Anticorpos/metabolismo , Encéfalo/embriologia , Encéfalo/metabolismo , Diferenciação Celular , Proliferação de Células , Interferon gama/metabolismo , Camundongos Endogâmicos BALB C , Transdução de Sinais
10.
Int J Dent ; 2021: 6671112, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679980

RESUMO

OBJECTIVE: Dental esthetic procedures are popular worldwide, and dentists are responsible for recommending several treatment options to their patients. To do this competently, dentists must have an educated opinion of their features. Therefore, we aimed to evaluate the self-perception of dental esthetics among male and female dental students and assess its effect on their desired treatment. Methodology. We conducted a questionnaire-based cross-sectional study involving 450 male and female dental students from five academic years with different grade point averages (GPAs) and monthly household incomes. The questionnaire comprised four sections. The subjects selected their teeth-color preferences using a commercial shade guide. The outcomes were presented using descriptive statistics and were compared with Pearson's chi-square test. The level of statistical significance was set at a p-value of 0.05. RESULTS: Female students (52%) showed a significantly higher preference for changing their tooth color (shade B1 was desired most often), whereas male students reported a higher need for orthodontic treatment and ceramic veneers (p < 0.0001 and p=0.002). Fifth-year students were more satisfied with their teeth color as compared with 1st-year students (p=0.047). High-GPA students showed significantly lower confidence regarding their smiles (p=0.030). A high percentage of students (39.1%) with household incomes of less than 10,000 SR preferred tooth-colored restorations. CONCLUSION: We concluded that the majority of dental students were confident about their smiles. Senior students were more satisfied with their teeth color, while younger students desired whiter teeth. Bleaching and orthodontics were the most desired treatment options.

11.
J Contemp Dent Pract ; 20(2): 247-257, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31058643

RESUMO

AIM: This study aimed to examine the effect of postoperative home bleaching using 20% carbamide peroxide on the shear bond strengths of different adhesives to enamel and to verify the failure mode for each test specimen. MATERIALS AND METHODS: One hundred sound human molars were used in this study. Bonding procedures were performed on the flattened buccal enamel surfaces according to the manufacturer's instructions. OptiBond Solo Plus adhesive (Kerr), Single Bond Universal adhesive (3M ESPE) applied with both the total-etch and self-etch techniques, and Tetric N-Bond Universal adhesive (Ivoclar Vivadent) applied with both the total-etch and self-etch techniques were used, followed by resin composite post fabrication (Filtek Z350 XT; 3M ESPE). All specimens were thermo-cycled for 5000 cycles and then divided into the control (non-bleach) and postoperative bleaching groups (20% carbamide peroxide). The shear bond strength values were measured and compared between the two groups. Data were analyzed using one-way analysis of variance with Tukey's test (p = 0.05). The failure modes of debonded specimens were evaluated using a digital microscope (50×). The bonding interfaces of the resin composite posts to different enamel conditions (control and postoperative bleaching) were observed by a scanning electron microscope (SEM) before the shear bond test. RESULTS: The shear bond strength values of all tested adhesives were lower in the postoperative bleaching group than they were in the control (non-bleach) group, particularly the bond strength values of self-etch adhesives. CONCLUSION: The stability of bonded resin composite restorations to enamel, using different dental adhesives, could be compromised after the bleaching procedure at varying sensitivity levels. CLINICAL SIGNIFICANCE: Replacement of bonded resin composite restorations to enamel might be considered after bleaching procedures, especially if these restorations were previously bonded with self-etch adhesives.


Assuntos
Peróxido de Carbamida , Colagem Dentária , Resinas Compostas , Esmalte Dentário , Adesivos Dentinários , Humanos , Teste de Materiais , Peróxidos , Cimentos de Resina , Resistência ao Cisalhamento , Ureia
12.
Open Dent J ; 12: 664-678, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30369976

RESUMO

BACKGROUND: The rapid developments in the field of adhesive dental materials have led to improvements in many aspects of clinical dentistry. Adhesive bond strength plays an important role in determining the clinical performance and longevity of dental restorations. Nevertheless, bond strength tests have never been well-standardized, although a number of important recommendations have been made. OBJECTIVE: The aim of this paper is to critically review the validity of different bond strength testing methods for assessment of bonding effectiveness of adhesive materials to tooth structure and discuss factors that may affect bond strength measurement. DATA COLLECTION: Relevant literature published between 1983 and 2018 was collected and reviewed from the PubMed database and Google scholar resources. REVIEW RESULTS: Results of the current bond testing methods should be used to compare materials tested under the same laboratory settings, but they shouldn't be used to make direct inferences on their clinical behaviour. Shear and micro-shear tests, result in non-uniform stress distribution, stress concentration at the substrate area, and predominantly tensile stresses rather than shear stresses. Micro-tensile bond tests provide many advantages over the shear tests, although these methods are technique sensitive and labour intensive. CONCLUSION: Bond strength testing methods should be well-standardized, but there are many factors that cannot be fully controlled which leads to variation and misinterpretation of the data about the bonding abilities of adhesives. CLINICAL SIGNIFICANCE: New adhesive materials should be subjected to a combination of testing protocols to properly assess their bonding effectiveness.

13.
Case Rep Dent ; 2018: 4063165, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29977624

RESUMO

The selection of an appropriate treatment plan for cases of dental fluorosis depends on the severity of the condition. Ceramic veneers are considered the treatment of choice for moderate to severe cases of fluorosis given the optimum aesthetics, wear resistance, biocompatibility, and long-term results of these veneers. This case report describes a step-by-step rehabilitation of fluorosed teeth, using ceramic veneers in a 26-year-old Yemeni male. The patient presented at the restorative dentistry clinics at King Saud University complaining of an unpleasant smile and generalized tooth discoloration.

14.
Medicine (Baltimore) ; 97(20): e10780, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29768370

RESUMO

INTRODUCTION: Arginine is an essential amino acid that plays an important role in various body functions including cell division, wound healing, removal of ammonia, immune function, and release of hormones. Hyperargininemia, an autosomal recessive genetic disorder, is considered one of the least common urea cycle disorders. It rarely presents in the neonatal period but rather appears in children at the age between 2 and 4 years. CASE PRESENTATION: Herein, we demonstrate a case of a 14-year-old female who presented to the neurology clinic with several neurological complications, which were found to be a consequence of high levels of arginine discovered after performing a metabolic screening test. The hyperargininemia was because of a point mutation of A1 gene on 6q23 resulting in deficiency in arginase enzyme. The complications of this lately diagnosed case of hyperargininemia would have been avoided if a newborn screen were done as a part of a national program. CONCLUSION: This study presented certain neurological complications in a 14-year-old female who was lately diagnosed with hyperargininemia. Out case report strongly emphasizes the importance of establishing a national neonatal screening policy to ensure early detection of inherited metabolic disorders, in particular those which can be easily treated, in the Kingdom of Bahrain.


Assuntos
Diagnóstico Tardio , Transtornos Neurológicos da Marcha/etiologia , Hiperargininemia/complicações , Hiperargininemia/diagnóstico , Debilidade Muscular/etiologia , Adolescente , Barein , Feminino , Humanos , Hiperargininemia/genética , Recém-Nascido , Triagem Neonatal , Mutação Puntual
15.
Australas Phys Eng Sci Med ; 33(4): 329-34, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20938762

RESUMO

The performance of a digital mammography system (Siemens Mammomat Novation) using different target/filter combinations and tube voltage has been assessed. The objective of this study is to optimize beam quality selection based on contrast-to-noise ratio (CNR) and mean glandular dose (MGD). Three composition of breast were studied with composition of glandular/adipose of 30/70, 50/50, and 70/30. CNR was measured using 2, 4 and 6 cm-thick simulated breast phantoms with an aluminium sheet of 0.1 mm thickness placed on top of the phantom. Three target/filter combinations, namely molybdenum/molybdenum (Mo/Mo), molybdenum/rhodium (Mo/Rh) and tungsten/rhodium (W/Rh) with various tube voltage and mAs were tested. MGD was measured for each exposure. For 50/50 breast composition, Mo/Rh combination with tube voltage 26 kVp is optimal for 2 cm-thick breast. W/Rh combination with tube voltage 27 and 28 kVp are optimal for 4 and 6 cm-thick breast, respectively. For both 30/70 and 70/30 breast composition, W/Rh combination is optimal with tube voltage 25, 26 and 27 kVp, respectively. From our study it was shown that there are potential of dose reduction up to 11% for a set CNR of 3.0 by using beam quality other than that are determined by AEC selection. Under the constraint of lowest MGD, for a particular breast composition, calcification detection is optimized by using a softer X-ray beam for thin breast and harder X-ray beam for thick breast. These experimental results also indicate that for breast with high fibroglandular tissues (70/30), the use of higher beam quality does not always increase calcification detection due to additional structured noise caused by the fibroglandular tissues itself.


Assuntos
Mamografia/métodos , Intensificação de Imagem Radiográfica/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Mama/anatomia & histologia , Feminino , Humanos , Imagens de Fantasmas , Doses de Radiação
16.
Singapore Med J ; 49(12): e372-4, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19122939

RESUMO

Supernumerary derivative (22) syndrome is one of the rare genomic syndromes. It is characterised by severe mental retardation, microcephaly, failure to thrive, ear anomalies, preauricular tags or sinus, cleft palate or high arch palate, microganathia, renal anomalies, congenital cardiac defects and genital abnormalities in males. In 99 percent of the cases, one of the parents is a balanced carrier of a translocation between chromosome 11 and chromosome 22. We report the first known case, a female neonate, of supernumerary derivative (22) syndrome from Malaysia.


Assuntos
Anormalidades Múltiplas/genética , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 22/genética , Translocação Genética , Feminino , Humanos , Lactente , Síndrome
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