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1.
Mol Ecol ; 33(14): e17440, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38946459

RESUMO

We present palaeogenomes of three morphologically unidentified Anatolian equids dating to the first millennium BCE, sequenced to a coverage of 0.6-6.4×. Mitochondrial DNA haplotypes of the Anatolian individuals clustered with those of Equus hydruntinus (or Equus hemionus hydruntinus), the extinct European wild ass, secular name 'hydruntine'. Further, the Anatolian wild ass whole genome profiles fell outside the genomic diversity of other extant and past Asiatic wild ass (E. hemionus) lineages. These observations suggest that the three Anatolian wild asses represent hydruntines, making them the latest recorded survivors of this lineage, about a millennium later than the latest observations in the zooarchaeological record. Our mitogenomic and genomic analyses indicate that E. h. hydruntinus was a clade belonging to ancient and present-day E. hemionus lineages that radiated possibly between 0.6 and 0.8 Mya. We also find evidence consistent with recent gene flow between hydruntines and Middle Eastern wild asses. Analyses of genome-wide heterozygosity and runs of homozygosity suggest that the Anatolian wild ass population may have lost genetic diversity by the mid-first millennium BCE, a possible sign of its eventual demise.


Assuntos
DNA Mitocondrial , Fluxo Gênico , Haplótipos , Filogenia , Animais , DNA Mitocondrial/genética , Haplótipos/genética , Equidae/genética , Genoma Mitocondrial , Extinção Biológica , Fósseis , Genética Populacional , Variação Genética
2.
J Esthet Restor Dent ; 36(4): 620-631, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37950565

RESUMO

OBJECTIVE: Obtaining strong resin bonds to computer-aided design and computer-aided manufacturing (CAD-CAM) resin-based composites with dispersed fillers (CCRBCs) poses a challenge. Therefore, this study aimed to assess the effect of three universal adhesives and a two-component silane coupling agent on the shear bond strength to three (CCRBCs). MATERIALS AND METHODS: Eight hundred and sixty-four specimens of Brilliant Crios, Lava Ultimate, and Tetric CAD were polished or grit blasted, bonded with Adhese Universal DC, One Coat 7 Universal (OC7), and Scotchbond Universal Plus Adhesive (SBU) with or without a silane primer. Shear bond strength was measured after 24 h and 10,000 thermocycles. Linear regressions were performed (α = 0.05). RESULTS: After thermocycling, bond strengths were similar for the universal adhesives on polished Brilliant Crios and Lava Ultimate (p ≥ 0.408). Grit blasted Tetric CAD showed no significant differences (p ≥ 0.096). The silane primer had minimal impact on grit blasted Tetric CAD (p ≥ 0.384). The silane primer increased the bond strength of OC7 to Brilliant Crios (p = 0.001) but decreased the adhesion of SBU to Brilliant Crios and Lava Ultimate (p ≤ 0.018). CONCLUSIONS: Bond strength of universal adhesives varied with CCRBC type. The two-component silane coupling agent showed mixed effects on adhesive performance. CLINICAL SIGNIFICANCE: Selecting universal adhesives from the same CCRBC product line does not always guarantee superior bond strength. The efficacy of silane coupling agents differs based on the bonding substrate.


Assuntos
Colagem Dentária , Silanos , Silanos/química , Cimentos Dentários , Propriedades de Superfície , Materiais Dentários , Cimentos de Resina/química , Desenho Assistido por Computador , Teste de Materiais
4.
J Mater Sci Mater Med ; 33(4): 38, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35404019

RESUMO

Zeolite can impart antibacterial properties to dental materials in the long-term when incorporated with inorganic cations. However, due to its porosity, it may jeopardize the mechanical integrity of the dental material. The aim of this project was to determine the effect on physical properties when zeolite is added to commercially available Ag-reinforced Glass Ionomer Cement (GIC). Sample groups were prepared according to the percentage of zeolite-clinoptilolite (0% - control, 0.5%, 1%, 2%, and 4% wt) added to Ag-GIC. Water sorption, solubility, Vickers hardness, and flexural strength were determined. Specifically, 10 × 2 mm circular disks were fabricated for the Vickers hardness, water sorption, and water solubility tests and 25 × 5 × 2 mm bars were created for the flexural strength test. The results from the surface hardness, water sorption, and flexural strength tests suggested that adding 0.5-4% wt of zeolite to Ag-reinforced GIC did not diminish its physical properties. However, the water solubility results showed that higher concentrations (2-4% wt) of zeolite had a statistically significant increase in water solubility compared to the control. Up to 4% wt zeolite can be incorporated into Ag-reinforced GIC without compromising mechanical properties. Incorporation of 0.5-1% wt zeolite to Ag-reinforced GIC will maintain an adequate surface hardness, water sorption, and flexural strength without compromising water solubility. Further research is needed to determine the effects of higher water solubility on clinical efficacy of zeolite modified Ag-GIC. Graphical abstract.


Assuntos
Cimentos de Ionômeros de Vidro , Zeolitas , Teste de Materiais , Prata , Propriedades de Superfície , Água
5.
J Esthet Restor Dent ; 34(8): 1213-1220, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35934807

RESUMO

OBJECTIVE: To evaluate and compare the clinical performance of two nano-hybrid giomer restorative composite materials after 5 years. MATERIALS AND METHODS: Forty-four pairs of restorations (total n = 88) of a flowable giomer (Beautifil Flow Plus F00; Shofu Inc., Kyoto, Japan) and a conventional nano-hybrid giomer restorative material (Beautifil II; Shofu Inc.) were placed in Class I cavities after the application of a dentin adhesive (FL-Bond II; Shofu Inc.) and a flowable liner (Beautifil Flow Plus F03; Shofu Inc). After 5 years, 32 pairs of restorations were assessed using the modified United States Public Health Service criteria. Both tested materials were compared using Fisher's exact test and each tested clinical criterion for each material was analyzed separately with respect to different follow-up periods using Friedman's test (a = 0.05). RESULTS: None of the restorations showed complete retention loss, post-operative sensitivity, secondary caries or color change. There were no significant changes to any of the clinical criteria for each material during the 5-year evaluation period (p > 0.05) and no significant differences between the two materials in all clinical parameters after 5 years (p > 0.05). CONCLUSIONS: Five-year clinical performance of both two nano-hybrid giomer restorative materials was comparably acceptable and not significantly different for any of the parameters evaluated. CLINICAL SIGNIFICANCE: Nano-hybrid giomer-based materials are clinically acceptable for the restoration of occlusal cavities as they demonstrate excellent performance after 5 years.


Assuntos
Cárie Dentária , Restauração Dentária Permanente , Humanos , Restauração Dentária Permanente/métodos , Fluoretos , Bis-Fenol A-Glicidil Metacrilato/química , Resinas Compostas/química , Forramento da Cavidade Dentária , Cárie Dentária/terapia , Seguimentos
6.
Molecules ; 27(24)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36557980

RESUMO

Polymethyl methacrylate (PMMA), an acrylic resin used in orthodontic appliances and removable dentures for its biocompatibility and esthetics, may harbor bacteria on its surface. The present study investigated a new PMMA formula with Gantrez: an antibacterial copolymer of methyl vinyl ether and maleic acid (PVM/MA). Samples were tested for mechanical properties (surface hardness, flexural strength, water sorption, and water solubility) and effects against Streptococcus mutans. Six groups (0%-control, 5%, 10%, 15%, 20%, and 25% Gantrez) of n = 12 were fabricated for physical property tests and analyzed with one-way ANOVA and Prism 6. From these results, three groups (0%, 5%, and 10% Gantrez) were selected for antibacterial tests, and data were analyzed with one-way ANOVA and Tukey's multiple comparison test. Adding 5% and 10% Gantrez into PMMA significantly decreased S. mutans adhesion. There was no significant difference between the control vs. 5%, 10%, 15%, and 20% Gantrez (p > 0.05) for surface hardness, the control vs. 5% Gantrez (p > 0.05) for flexural strength, and the control vs. 5 and 10% Gantrez for water sorption and water solubility. Overall, incorporating 5% Gantrez into PMMA may be a promising solution to reduce bacterial adhesion without changing the acrylic resin's physical properties.


Assuntos
Anti-Infecciosos , Polimetil Metacrilato , Resinas Acrílicas , Propriedades de Superfície , Antibacterianos/farmacologia , Água , Teste de Materiais
7.
J Fish Biol ; 99(1): 37-48, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33559126

RESUMO

The genetic diversity of the Mediterranean swordfish (Xiphias gladius Linneus) has not been explored extensively at its easternmost range so far. In this study, modern X. gladius samples from the eastern part of the Mediterranean basin, north of the Aegean Sea (Aegean-2013, n = 26) and the Mediterranean coast of Turkey (N.Levantine-2013, n = 42) were studied genetically, along with ancient samples from Yenikapi excavation (n = 6). Partial mitochondrial DNA control region sequences (entire sequences, clade I and clade II) were evaluated spatially and temporally together with previously published sequences (Alvarado Bremer et al., Molecular Phylogenetics and Evolution, 2005, 36, 169-187; Viñas et al., ICES Journal of Marine Science, 2010, 67, 1222-1229; Righi et al., Diversity, 2020, 12, 170) from the rest of the Mediterranean Sea. Pair-wise FST and pair-wise AMOVA tests showed that, in general, groups of eastern populations and western Mediterranean populations have not genetically differed from each other significantly nearly in the past 20 years. Therefore, the results direct reconsideration of previous descriptions of population sub-structure within the Mediterranean and support high gene flow throughout the region. On the contrary, the results of this study confirmed the existence of genetic diversity differences between western and eastern Mediterranean, with eastern being low. One-tailed permutation tests revealed that θ, which is directly proportional to long-term female effective population size (Ne), decreased significantly (P < 0.05) in both regions over the past two decades. On the Turkish coasts, θ is not significantly different from that of the nearly contemporary eastern Mediterranean population. Nonetheless, θ of the ancient sample was consistently and significantly (P < 0.001) higher than those of the eastern and western Mediterranean populations in clade I and clade II. Furthermore, it contains two mitochondrial haplotypes that are not observed in modern samples, suggesting that the Ne of X. gladius in the eastern was high in Byzantium times. Eight microsatellite loci were also genotyped in modern samples. The microsatellite-based present Ne estimate of the pooled Aegean-2013 and N.Levantine-2013 populations was lower than 1000 according to the upper limit of 95% c.i. and possibly even lower than 100 according to the mean of posterior distribution of the present Ne estimate calculated by the software package MSVAR. These alarming genetic signals for the sustainability of X. gladius on the coasts of Turkey are in agreement with the nearly collapsing X. gladius fisheries as depicted also in the fisheries statistics. Overall, congruent with the previous studies, the data presented here show that sustainability of the X. gladius population in Mediterranean is under major threat. Therefore, X. gladius around the Turkish coasts need an immediate stringent action and management plan.


Assuntos
DNA Mitocondrial , Perciformes , Animais , DNA Mitocondrial/genética , Demografia , Feminino , Mar Mediterrâneo , Repetições de Microssatélites , Turquia
8.
J Prosthet Dent ; 126(5): 698-702, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33121822

RESUMO

STATEMENT OF PROBLEM: Optimal composite resin bonds to polymer-infiltrated ceramic network (PICN) computer-aided design and computer-aided manufacturing (CAD-CAM) materials are essential for clinical success. However, comparative bond strength studies on the influence of different etching and cleaning methods on these materials are lacking. PURPOSE: The purpose of this in vitro study was to measure and compare the microshear bond strength (µSBS) of a composite resin cement with that of a PICN material after different surface treatment and cleaning methods. MATERIAL AND METHODS: Seventy specimens of a CAD-CAM PICN were divided into 7 groups (n=10): no treatment (control), hydrofluoric acid etching for 20 seconds (HF20), 60 seconds (HF60), 120 seconds (HF120), HF20 + phosphoric acid for 60 seconds and ultrasonic bath for 5 minutes, HF60 + PH, and HF120 + PH. After surface treatment, a silane coupling agent and composite resin cement were applied. Microshear bond strength was determined, and data were analyzed with 1-way ANOVA and Tukey post hoc multiple comparison tests (α=.05). RESULTS: All HF acid treatments resulted in a significant increase in bond strength to the polymer-infiltrated ceramic network material (P=.02). Bond strength values for HF etching for 20 seconds were significantly lower than those for 60 seconds and 120 seconds (P=.034). No difference was found between 60 seconds and 120 seconds of HF etching time (P=.986). Additional surface treatment with phosphoric acid 60 seconds and ultrasonic bath 5 minutes did not improve the bond strength beyond values obtained by hydrofluoric acid treatment only (P=.834). Most failures were cohesive. CONCLUSIONS: Acid etching and surface treatment have significant effects on composite resin bond strength to a PICN CAD-CAM material. HF etching for 60 seconds or 120 seconds provides the highest bond strengths. Cleaning methods after etching did not have any significant effect on bond strength.


Assuntos
Colagem Dentária , Cerâmica , Desenho Assistido por Computador , Porcelana Dentária , Ácido Fluorídrico , Teste de Materiais , Polímeros , Cimentos de Resina , Silanos , Propriedades de Superfície
9.
Molecules ; 26(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34684777

RESUMO

Zeolites and zeolitic imidazolate frameworks (ZIFs) are widely studied as drug carrying nanoplatforms to enhance the specificity and efficacy of traditional anticancer drugs. At present, there is no other systematic review that assesses the potency of zeolites/ZIFs as anticancer drug carriers. Due to the porous nature and inherent pH-sensitive properties of zeolites/ZIFs, the compounds can entrap and selectively release anticancer drugs into the acidic tumor microenvironment. Therefore, it is valuable to provide a comprehensive overview of available evidence on the topic to identify the benefits of the compound as well as potential gaps in knowledge. The purpose of this study was to evaluate the potential therapeutic applications of zeolites/ZIFs as drug delivery systems delivering doxorubicin (DOX), 5-fluorouracil (5-FU), curcumin, cisplatin, and miR-34a. Following PRISMA guidelines, an exhaustive search of PubMed, Scopus, Embase, and Web of Science was conducted. No language or time limitations were used up to 25th August 2021. Only full text articles were selected that pertained to the usage of zeolites/ZIFs in delivering anticancer drugs. Initially, 1279 studies were identified, of which 572 duplicate records were excluded. After screening for the title, abstract, and full texts, 53 articles remained and were included in the qualitative synthesis. An Inter-Rater Reliability (IRR) test, which included a percent user agreement and reliability percent, was conducted for the 53 articles. The included studies suggest that anticancer drug-incorporated zeolites/ZIFs can be used as alternative treatment options to enhance the efficacy of cancer treatment by mitigating the drawbacks of drugs under conventional treatment.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Zeolitas , Animais , Antineoplásicos/farmacocinética , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Portadores de Fármacos/química , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Nanopartículas/química , Neoplasias/metabolismo , Porosidade , Células Tumorais Cultivadas , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/fisiologia , Zeolitas/química
10.
Br J Neurosurg ; 32(2): 196-200, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29706112

RESUMO

PURPOSE: Ventriculoperitoneal shunt (VPS) is the most common treatment modality for hydrocephalus. However, VPS infection is a common and serious complication with high rates of mortality and morbidity. The objective of this study was to investigate causative agents and the management of VPS infections and to identify risk factors for re-infection in children. MATERIALS AND METHODS: Retrospective, multicentre study on patients with VPS infection at paediatric and neurosurgery departments in four tertiary medical centres in Turkey between January 2011 and September 2014. RESULTS: A total of 290 patients with VPS infections were identified during the study period. The aetiology of hydrocephalus was congenital malformations in 190 patients (65.5%). The most common symptom of shunt infection was fever in 108 (37.2%) cases. At least one pathogen was identified in 148 VPS infections (51%). The most commonly isolated pathogen was coagulase-negative staphylococci, which grew in 63 cases (42.5%), followed by Pseudomonas aeruginosa in 22 cases (14.9%), Klebsiella pneumoniae in 15 cases (10.1%), and Staphylococcus aureus in 15 cases (10.1). The median duration of VPS infection was 2 months (range, 15 days to 60 months) after insertion of the shunt, with half (49.8%) occurring during the first month. VPS infection was treated by antibiotics and shunt removal in 211 cases (76.4%) and antibiotics alone without shunt removal in 65 patients (23.5%). Among the risk factors, CSF protein level greater than 100 mg/dL prior to VPS insertion was associated with a potential risk of re-infection (OR, 1.65; p =.01). CONCLUSION: High protein levels (>100 mg/dL) before the re-insertion of a VPS may be a risk factor for VPS re-infection.


Assuntos
Infecções Bacterianas/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Derivação Ventriculoperitoneal/efeitos adversos , Adolescente , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Proteínas do Líquido Cefalorraquidiano/análise , Criança , Pré-Escolar , Remoção de Dispositivo , Feminino , Humanos , Hidrocefalia/cirurgia , Lactente , Masculino , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/microbiologia , Recidiva , Estudos Retrospectivos , Fatores de Risco , Turquia/epidemiologia
11.
J Esthet Restor Dent ; 30(6): 551-556, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30378235

RESUMO

OBJECTIVE: To evaluate the influence of saliva contamination and cleaning procedures on shear bond strength (SBS) of a self-adhesive resin cement (SAC) to zirconia surfaces. MATERIALS AND METHODS: A total of 160 sandblasted zirconia blocks were randomly divided into eight groups as follows: No saliva contamination, no cleansing (NC-NC); contamination with saliva, no cleansing (SC-NC); no saliva contamination, cleansing with a zirconia primer (ZP; Z-Bond, Danville Materials, Inc., S. Ramon, California) (NC-ZP); contamination with saliva, cleansing with ZP (SC-ZP); no saliva contamination, cleansing with hydrofluoric acid (HF; Ultradent Porcelain Etch; Ultradent Products, South Jordan, Utah) followed by cleansing with ZP (NC-HF-ZP); contamination with saliva, cleansing with HF followed by cleansing with ZP (SC-HF-ZP); cleansing with ZP, contamination with saliva, cleansing with ZP (ZP-SC-ZP); application of ZP, contamination with saliva, cleansing with HF followed by cleansing with ZP (ZP-SC-HF-ZP). Cylindrical resin composite blocks were luted to the zirconia surfaces with SAC (Clearfil SA Cement Automix, Kuraray, Inc., Tokyo, Japan). Specimens were subjected to shear forces at a cross-head speed of 0.5 mm/min. Data were analyzed with Analysis of Variance and Tukey tests (α = 0.05). RESULTS: The bond strength values to zirconia were significantly influenced by saliva contamination (P < .05). The SC-NC group showed the lowest bond strength values (5.6 ± 1.4 MPa; P < .05). All cleansing or pretreatment agents improved the bond strengths when compared to noncleansing groups, NC-NC and SC-NC. CONCLUSION: In situations where saliva contamination is deemed unavoidable, application of ZP after try-in of the zirconia restoration could be beneficial for the accurate cementation. CLINICAL SIGNIFICANCE: During try-in sessions of fixed dental prostheses, zirconia ceramic restoration may come into contact with saliva and surfaces should be cleansed to obtain an optimal surface for adhesion. Application of zirconia primer to the sandblasted zirconia surface is recommended whether the surface is contaminated with saliva or not.


Assuntos
Colagem Dentária , Análise do Estresse Dentário , Japão , Teste de Materiais , Cimentos de Resina , Saliva , Propriedades de Superfície , Zircônio
12.
J Prosthet Dent ; 119(6): 987-993, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29042115

RESUMO

STATEMENT OF PROBLEM: A recommended minimum thickness for monolithic zirconia restorations has not been reported. Assessing a proper thickness that has the necessary load-bearing capacity but also conserves dental hard tissues is essential. PURPOSE: The purpose of this in vitro study was to evaluate the effect of thickness and surface modifications on monolithic zirconia after simulated masticatory stresses. MATERIAL AND METHODS: Monolithic zirconia disks (10 mm in diameter) were fabricated with 1.3 mm and 0.8 mm thicknesses. For each thickness, 21 disks were fabricated. The specimens of each group were further divided into 3 subgroups (n=7) according to the surface treatments applied: untreated (control), airborne-particle abrasion with 50-µm Al2O3 particles at a pressure of 400 kPa at 10 mm, and grinding with a diamond rotary instrument followed by polishing. The biaxial flexure strength was determined by using a piston-on-3-balls technique in a universal testing machine. Flexural loading was applied with a 1.4-mm diameter steel cylinder, centered on the disk, at a crosshead speed of 0.5 mm/min until fracture occurred. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses were performed. The data were statistically analyzed with 2-way ANOVA, Tamhane T2, 1-way ANOVA, and Student t tests (α=.05). RESULTS: The 1.3-mm specimens had significantly higher flexural strength than the 0.8-mm specimens (P<.05). Airborne-particle abrasion significantly increased the flexural strength (P<.05). Grinding and polishing did not affect the flexural strength of the specimens (P>.05). CONCLUSIONS: The mean flexural strength of 0.8-mm and 1.3-mm thick monolithic zirconia was greater than reported masticatory forces. Airborne-particle abrasion increased the flexural strength of monolithic zirconia. Grinding did not affect flexural strength if subsequently polished.


Assuntos
Zircônio , Resistência à Flexão , Mastigação , Difração de Raios X
13.
Acta Medica (Hradec Kralove) ; 60(3): 124-126, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29439759

RESUMO

We present a rare case of a patient with a persistent headache for many years found to have an intracranial nail present for nearly 65 years. The nail was found entering approximately 1 cm from the midline on the left side, passing below the superior sagittal sinus, with the tip 1.5 mm right of the frontal horn of the lateral ventricle. Treatment strategies designed to optimize outcome for intracranial foreign bodies and possible complications are discussed in this report. We also discuss the decision for surgical intervention for foreign bodies and the relevance of position of the foreign body.


Assuntos
Corpos Estranhos/diagnóstico por imagem , Traumatismos Cranianos Penetrantes/diagnóstico por imagem , Transtornos da Cefaleia/etiologia , Idoso , Feminino , Traumatismos Cranianos Penetrantes/complicações , Humanos , Tomografia Computadorizada por Raios X
14.
BMC Oral Health ; 16(1): 103, 2016 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-27670292

RESUMO

BACKGROUND: This study aimed to investigate the effects of a fluoride varnish with added Casein Phosphopeptide-Amorphous Calcium Phosphate (CPP-ACP) treatments on acid resistance of primary teeth enamel. METHODS: Enamel specimens obtained from 40 primary incisors (for surface microhardness testing) and 40 primary molars (for demineralization depth measurement) were randomly divided into four groups (n = 10 incisors and 10 molars) each according to surface treatment: no treatment (control), MI varnish (1-8 % sodium fluoride and 1-5 % CPP-ACP), Clinpro White (1-5 % sodium fluoride and <5 % modified tricalcium phosphate), Duraphat (<5 % sodium fluoride). Specimens were stored for 24 h in a moist environment. After varnish residues were removed, specimens were subjected to pH cycling. The effects of fluoride varnishes were evaluated according to surface microhardness, lesion depth and structural changes. Results were analyzed by ANOVA and Tukey's tests. RESULTS: The lowest changes in surface microhardness and lesion depth occurred in MI varnish group, followed by the Clinpro White, Duraphat and no treatment (control) group (for percentage of loss surface microhardness -20.80, -34.60, -57.80 and -73.40; for lesion depth values 23.60 µm ± 3.36, 29.85 µm ± 3.27, 40.37 µm ± 3.41 and 54.56 µm ± 4.16, respectively). Statistically significant differences in both surface microhardness and lesion depth were observed among all groups (P < 0.05). CONCLUSIONS: Within the limitations of this in vitro study, fluoride varnish containing CPP-ACP was more effective in increasing the acid resistance of primary enamel than other fluoride varnishes. However, further clinical research is needed to confirm these in vitro results.

15.
J Adhes Dent ; 17(6): 545-50, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26734679

RESUMO

PURPOSE: To compare the bonding performance of three new self-adhesive resin cements to human dentin after storage under two different conditions. MATERIALS AND METHODS: Buccal, lingual, mesial, and distal dentin surfaces of 36 human molars were abraded to directly below the enamel with #600 SiC papers. The teeth were divided into two main test groups. In the first test group (FT), the cements were kept in a refrigerator (6 ± 2°C) for three months and then used for the test. The remainder of the cements was kept at a constant room temperature of 19 ± 2°C for an additional three months, and then used again for the second test group (ST). Each test group comprised 6 teeth and 24 dentin sections. The cements Clearfil SA (CSA), G-Cem (GC), and Bis-Cem (BC) were applied to the surfaces according to the manufacturers' recommendations. After application of the cements to the flat dentin surfaces and light curing, shear bond strengths were determined at a crosshead speed of 0.5 mm/min. Bond strengths were then calculated and expressed in MPa. Data were analyzed with Kruskal-Wallis and Wilcoxon Signed Rank tests. To investigate the cement/ dentin interfaces using SEM, the buccal surfaces of three additional teeth were used for each test group. RESULTS: The bond strength values of cement groups were significantly different for the FT and ST groups (p < 0.01). GC showed the highest bond strength values of all materials. There was a difference between the bond strength values of the two testing periods for all materials (p < 0.01). Bond strengths significantly decreased after storage at room temperature. CONCLUSION: Storage temperatures considerably affect the shelf life of self-adhesive resin cements.


Assuntos
Colagem Dentária , Cimentos de Resina/química , Temperatura Baixa , Resinas Compostas/química , Dentina/ultraestrutura , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Humanos , Cura Luminosa de Adesivos Dentários , Teste de Materiais , Microscopia Eletrônica de Varredura , Resistência ao Cisalhamento , Estresse Mecânico , Propriedades de Superfície , Temperatura , Fatores de Tempo
16.
J Adhes Dent ; 16(1): 7-14, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24027770

RESUMO

PURPOSE: This study compared the microtensile bond strengths (µTBS) of two different self-etching (SE) and etchand- rinse (ER) adhesive systems to enamel affected by hypoplastic amelogenesis imperfecta (HPAI) and analyzed the enamel etching patterns created by the two adhesive systems using scanning electron microscopy (SEM). MATERIALS AND METHODS: Sixteen extracted HPAI-affected molars were used for the bond strength tests and 2 molars were examined under SEM for etching patterns. The control groups consisted of 12 healthy third molars for µTBS tests and two molars for SEM. Mesial and distal surfaces of the teeth were slightly ground flat. The adhesive systems and composite resin were applied to the flat enamel surfaces according to the manufacturers' instructions. The tooth slabs containing composite resin material on their mesial and distal surfaces were cut in the mesio-distal direction with a slow-speed diamond saw. The slabs were cut again to obtain square, 1-mm-thick sticks. Finally, each stick was divided into halves and placed in the µTBS tester. Bond strength tests were performed at a speed of 0.5 mm/min. Data were analyzed with two-way ANOVA and Tukey's tests. RESULTS: There was no significant difference between the bond strength values of ER and SE adhesives (p > 0.05). However, significant differences were found between HPAI and control groups (p < 0.05). HPAI-affected enamel surfaces exhibited mild intra- and inter-prismatic enamel etching patterns after orthophosphoric acid application, while conditioning of HPAI-affected enamel with SE primer created a slightly rough and grooved surface. CONCLUSION: SE and ER adhesive systems provide similar bond strengths to HPAI-affected enamel surfaces.


Assuntos
Amelogênese Imperfeita/patologia , Colagem Dentária , Cimentos Dentários/química , Esmalte Dentário/ultraestrutura , Condicionamento Ácido do Dente/métodos , Resinas Compostas/química , Análise do Estresse Dentário/instrumentação , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Ácidos Fosfóricos/química , Cimentos de Resina/química , Estresse Mecânico , Resistência à Tração
17.
J Prosthet Dent ; 112(3): 455-64, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24680355

RESUMO

STATEMENT OF PROBLEM: Information regarding the effect of thermomechanical aging (TMA) on the bond strength of luting cements to root canal dentin and endodontic posts is limited. PURPOSE: The purpose of this study was to investigate the effect of TMA on the bond strength of fiber and zirconia posts bonded to root canal dentin with 2 different resin cements with microtensile and scanning electron microscopic evaluation. MATERIAL AND METHODS: Eighty extracted single-rooted human premolars were endodontically treated and restored with either a glass fiber post (FP) or a zirconia post (ZP) with 2 commercially available resin luting cements. The teeth were divided into 2 main groups. In the first group, posts (n=40) were bonded with a self-etch adhesive cement (SEAC). In the second group (n=40), posts were bonded using a self-adhesive cement (SAC). During the first aging phase, all specimens in each group were stored in distilled water for 30 days at 37°C. During the second phase, half of the specimens in each group were subjected to the TMA. The test groups were as follows: FP/SEAC, FP/SEAC+TMA, ZP/SEAC, ZP/SEAC+TMA, FP/SAC, FP/SAC+TMA, ZP/SAC, and ZP/SAC+TMA. The bond strength was measured with a microtensile test. Data were analyzed by 3-way analysis of variance and the Tukey honest significant different test (α=.05). RESULTS: FP/SEAC at 30 days was higher than in the other groups. However, bond strength values were significantly reduced in this group after TMA (P<.001). CONCLUSIONS: Bond strength values and physical properties of SEAC with higher filler content were more affected by the TMA than those of SALC. According to scanning electron microscopic observation, TMA also affected the micromorphologic interface between the posts and the resin cements as well as between the resin cements and the root canal dentin.


Assuntos
Colagem Dentária , Materiais Dentários/química , Vidro/química , Técnica para Retentor Intrarradicular/instrumentação , Cimentos de Resina/química , Zircônio/química , Condicionamento Ácido do Dente/métodos , Planejamento de Prótese Dentária , Cavidade Pulpar/ultraestrutura , Análise do Estresse Dentário/instrumentação , Dentina/ultraestrutura , Resinas Epóxi/química , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Preparo de Canal Radicular/métodos , Estresse Mecânico , Propriedades de Superfície , Temperatura , Resistência à Tração , Fatores de Tempo , Dente não Vital/terapia , Água/química
18.
Proc Inst Mech Eng H ; : 9544119241248232, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38706301

RESUMO

The aim of this study was to evaluate the effect of rotation frequency (rpm) of different polishing discs on the surface roughness of a nanohybrid resin composite material. 126 specimens were prepared in metal molds of 10 mm diameter and 2 mm depth using a nanohybrid resin composite material. The prepared specimens were kept in distilled water for 24 hours. Polishing treatments at 5k, 10k, 15k, and 20k rpm were applied to the nanohybrid resin composite material by grouping different brand polishing discs: Sof-Lex Contouring and Polishing Discs (3M Espe, USA) (3M Group), Optidisc (Kerr Corporation, USA) (Kerr Group), Super-Snap Rainbow Technique Kit (Shofu Dental, Japan) (Shofu Group), Finishing Disc (Bisco Dental, USA) (Bisco Group). The surface roughness was evaluated at three different points by atomic force microscopy for all specimens and scanning electron microscopy was used for visual assessment. Data were evaluated by Two Way ANOVA and Tukey's HSD Test. The mean surface roughness (Ra, µm) of all prepared samples showed significant differences (α = 0.05). According to Two-Way ANOVA, there is a statistically significant relationship between the rpm values and the discs. The 3M group showed the highest roughness value at all rpm speeds. Shofu group at 15k, 20k rpm, Bisco group at 10k, 15k, 20k rpm, the Kerr group at 15k, 20k rpm showed the lowest roughness value and had roughness close to the surfaces finished with a mylar strip. The smoothest surfaces were obtained at 15k rpm, even though polishing discs from different brands were used. It was also observed that 5k and 20k rpm polishing speeds can increase the surface roughness of the nanohybrid resin composite material.

19.
Biomimetics (Basel) ; 9(3)2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38534867

RESUMO

The popular immediate dentin sealing (IDS) technique is used to improve the bond strength of indirect restorations. This systematic review assessed whether bond strength is affected by the type of aging conditions, bonding agents, flowable resin composites, impression materials, temporary materials, and/or resin cement used within the IDS procedure. A comprehensive database search of PubMed, Embase, Scopus, Ovid Medline, Web of Sciences, Cochrane Library, Dentistry & Oral Sciences Source, and ProQuest was carried out up to 30 January 2024 without publication year or language limitations. Only in vitro full-texts regarding the effect of IDS on bond strength were included, and the quality of their methods was assessed via a Risk of Bias (RoB) test. In total, 1023 pertinent studies were initially found, and 60 articles were selected for review after screening for the title, abstract, and full texts. IDS application improves the bond strength of indirect restorations to dentin and reduces the negative effects of temporary materials on the bond durability of final indirect restorations. Filled dentin bonding agents or combinations with flowable resin composite are preferred to protect the IDS layer from conditioning procedures.

20.
Biomimetics (Basel) ; 9(6)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38921245

RESUMO

BACKGROUND: Zeolite can release antimicrobial silver ions in a targeted and controlled manner for an extended time, selectively inhibiting the growth of pathogenic oral bacteria when added to dental materials. The objective of this study was to investigate the effect of the addition of zeolite to silver-reinforced glass ionomer cement on the release of silver ions over time. METHODS: Five concentrations of silver-zeolite (0%, 0.5%, 1%, 2%, 4% wt) were incorporated into silver-reinforced GIC in the form of 10 mm × 2 mm circular disks (n = 5). The disks were incubated in deionized water at 37 °C and ion release from the samples was measured at 1, 2, 7, and 30 days after immersion by inductively coupled atomic emission spectroscopy. RESULTS: Incorporating silver-zeolite increased silver ion release from silver-reinforced GIC disks compared to the control disks (p < 0.05), while incorporating zeolite alone had no effect. Higher concentrations of added silver-zeolite resulted in increased silver ion release. Sustained silver ion release was observed for up to 30 days. CONCLUSION: Adding silver-zeolite to silver-reinforced GIC may enhance its extended antibacterial effect in the oral cavity.

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