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1.
Artigo em Inglês | MEDLINE | ID: mdl-39001716

RESUMO

OBJECTIVES: Escherichia coli can cause infections in the urinary tract and in normally sterile body sites leading to invasive E. coli disease (IED), including bacteraemia and sepsis, with older populations at increased risk. We aimed to estimate the theoretical coverage rate by the ExPEC4V and 9V vaccine candidates. In addition, we aimed at better understanding the diversity of E. coli isolates, including their genetic and phenotypic antimicrobial resistance (AMR), sequence types (STs), O-serotypes and the bacterial population structure. METHODS: Blood and urine culture E. coli isolates (n = 304) were collected from hospitalized patients ≥60 years (n = 238) with IED during a multicentric, observational study across three continents. All isolates were tested for antimicrobial susceptibility, O-serotyped, whole-genome sequenced and bioinformatically analysed. RESULTS: A large diversity of STs and of O-serotypes were identified across all centres, with O25b-ST131, O6-ST73 and O1-ST95 being the most prevalent types. A total of 45.4% and 64.7% of all isolates were found to have an O-serotype covered by the ExPEC4V and ExPEC9V vaccine candidates, respectively. The overall frequency of MDR was 37.4% and ST131 was predominant among MDR isolates. Low in-patient genetic variability was observed in cases where multiple isolates were collected from the same patient. CONCLUSIONS: Our results highlight the predominance of MDR O25b-ST131 E. coli isolates across diverse geographic areas. These findings provide further baseline data on the theoretical coverage of novel vaccines targeting E. coli associated with IED in older adults and their associated AMR levels.

2.
Langmuir ; 40(9): 4601-4614, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38323922

RESUMO

The contact between nanoscale single-crystal silicon asperities and substrates terminated with -H and -OH functional groups is simulated using reactive molecular dynamics (MD). Consistent with previous MD simulations for self-mated surfaces with -H terminations only, adhesion is found to be low at full adsorbate coverages, be it self-mated coverages of mixtures of -H and -OH groups, or just -OH groups. As the coverage reduces, adhesion increases markedly, by factors of ∼5 and ∼6 for -H-terminated surfaces and -OH-terminated surfaces, respectively, and is due to the formation of covalent Si-Si bonds; for -OH-terminated surfaces, some interfacial Si-O-Si bonds are also formed. Thus, covalent linkages need to be broken upon separation of the tip and substrate. In contrast, replacing -H groups with -OH groups while maintaining complete coverage leads to negligible increases in adhesion. This indicates that increases in adhesion require unsaturated sites. Furthermore, plane-wave density functional theory (DFT) calculations were performed to investigate the energetics of two Si(111) surfaces fully terminated by either -H or -OH groups. Importantly for the adhesion results, both DFT and MD calculations predict the correct trends for the relative bond strengths: Si-O > Si-H > Si-Si. This work supports the contention that prior experimental work observing strong increases in adhesion after sliding Si-Si nanoasperities over each other is due to sliding-induced removal of passivating species on the Si surfaces.

3.
J Arthroplasty ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38734327

RESUMO

BACKGROUND: Cobalt-chromium-molybdenum (CoCrMo) and titanium alloys have been used for orthopaedic implants for decades. However, recent evidence has shown that inflammatory cell-induced corrosion (ICIC) can damage these metal alloys. This study aimed to investigate the mechanisms of ICIC by coculturing macrophages with lymphocytes. We hypothesized that macrophages would be able to alter the surface oxide layer of CoCrMo and titanium alloy (Ti6Al4V) disks, with greater oxide layer damage occurring in groups with a coculture compared to a macrophage monoculture and in groups with inflammatory activators compared to nonactivated groups. METHODS: Murine macrophages were cultured on American Society for Testing and Materials F1537 CoCrMo and F136 Ti6Al4V disks for 30 days and activated with interferon gamma and lipopolysaccharide. Interferon gamma and lipopolysaccharide were added to the culture medium to simulate local inflammation. Macrophages were either cultured alone or in a coculture with T helper lymphocytes. After the 30-day experiment, scanning electron microscopy was used to examine the disk surfaces, and oxide levels were found using energy dispersive x-ray spectroscopy. RESULTS: Pitting features consistent with previous reports of ICIC were found on disks cultured with cells. Both CoCrMo and Ti6Al4V disks had significantly lower oxide levels in all groups with cells compared to control groups with no cells (P < .01). Additionally, CoCrMo disks had significantly lower oxide levels when cultured with activated macrophages and lymphocytes compared to nonactivated macrophages alone (P < .001), activated macrophages alone (P < .01), and nonactivated macrophages and lymphocytes (P < .05). No differences in the oxide levels were found among the Ti6Al4V groups. CONCLUSIONS: This study demonstrates the ability of macrophages to alter the surface chemistry of commonly used orthopaedic alloys. We found that the addition of lymphocytes and a simulated local inflammatory response may contribute to the ICIC of CoCrMo implants.

4.
Am J Dent ; 37(1): 53-56, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38458984

RESUMO

PURPOSE: To evaluate flow profile and non-Newtonian behavior of 10 different silicone lining materials. METHODS: Ten commercially available silicone lining materials were selected for evaluation. The flow profile and non-Newtonian behavior of each material was measured using a shark fin testing method. Fin height and resultant base thickness were measured with a digital caliper and compared with one-way ANOVA and Student-Newman-Keuls post hoc test and fin base by Kruskal-Wallis one-way ANOVA on ranks with Dunn post hoc test with significance at P< 0.05 for both. RESULTS: Shark fin heights ranged from 9.62 ± 0.86 mm [Reline II (Soft)] to 25.54 ± 0.43 mm [Sofreliner (Medium)]. Shark fin bases ranged from 2.57 ± 0.51 mm [Sofreliner (Medium)] to 10.31 ± 0.57 mm [Reline II (Soft)]. Statistically significant differences were found between certain samples' shark fin heights as well as resultant bases (P< 0.05) indicating different rheological properties. CLINICAL SIGNIFICANCE: Silicone liner materials differ significantly with respect to flow profile and non-Newtonian behavior. While a high flow profile (low viscosity) of an elastomeric impression material improves accuracy, it may be a detriment to a denture lining material that must achieve a critical minimum thickness to provide resilience. Likewise, a low flow profile (high viscosity) material may also pose a disadvantage, requiring excessive compression and possible tissue distortion to achieve the same critical thickness. The results of this study should be considered when selecting the appropriate material for clinical application. Additional studies are indicated to further quantify rheological properties as well as correlate them to physical properties after the complete cure of the material.


Assuntos
Reembasadores de Dentadura , Silicones , Humanos , Viscosidade , Teste de Materiais , Bases de Dentadura , Elastômeros de Silicone , Propriedades de Superfície
5.
J Prosthet Dent ; 131(6): 1250.e1-1250.e8, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38485594

RESUMO

STATEMENT OF PROBLEM: New denture base acrylic resins have been introduced that are specifically formulated for microwave polymerization. Microwave polymerization is a time-efficient procedure, but few studies have evaluated how these new acrylic resin formulations compare with conventionally processed acrylic resins. PURPOSE: The purpose of this in vitro study was to compare the stiffness and strength of denture base acrylic resins formulated for microwave polymerization with conventionally processed acrylic resin. MATERIAL AND METHODS: Rectangular beams were fabricated from 2 microwave-polymerized denture base acrylic resins, microwave-specific resin (Nature-Cryl MC), resin with the option of microwave polymerization (Diamond D), and a conventionally processed resin as a control (Lucitone 199). Specimens (n=10) were stored in water for 1 week and subjected to a 3-point bend test to determine the flexural modulus (stiffness) and flexural strength before (initial properties) or after 120 000 load cycles. The load cycles, conducted between 5 and 25 N at 2 Hz, simulated 6 months of mastication. Data were analyzed by using 2-way ANOVA, followed by pairwise comparisons (α=.05). RESULTS: The initial flexural modulus (mean ±standard deviation) was conventionally processed resin, 2.65 ±0.33 GPa; microwave-specific resin, 3.01 ±0.20 GPa; and microwave-option resin, 2.63 ±0.04 GPa. After load cycling, the mean flexural modulus was conventionally processed resin, 2.34 ±0.32 GPa; microwave-specific resin, 2.69 ±0.20 GPa; and microwave-option resin, 1.96 ±0.11 GPa. The initial flexural strength was conventionally processed resin, 77.6 ±11.0 MPa; microwave-specific resin, 83.6 ±3.5 MPa; and microwave-option resin, 78.9 ±2.6 MPa. After load cycling, the mean flexural strength was conventionally processed resin, 68.7 ±9.0 MPa; microwave-specific resin, 73.3 ±3.3 MPa; and microwave-option resin, 65.5 ±3.5 MPa. Resin and loading state significantly affected the stiffness and strength (P<.01); the interaction resin×state was not significant (P≥.558). CONCLUSIONS: Microwave-polymerized denture base acrylic resins were comparable in stiffness and strength with conventionally processed acrylic resin. All acrylic resins decreased in stiffness and strength after load cycling. The microwave-specific resin was significantly stiffer and stronger than the other denture base acrylic resins, initially and after 120 000 load cycles.


Assuntos
Resinas Acrílicas , Bases de Dentadura , Teste de Materiais , Micro-Ondas , Polimerização , Resinas Acrílicas/química , Resistência à Flexão , Análise do Estresse Dentário , Materiais Dentários/química , Materiais Dentários/efeitos da radiação , Módulo de Elasticidade , Técnicas In Vitro
6.
Clin Infect Dis ; 76(3): e1236-e1243, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35684979

RESUMO

BACKGROUND: Extraintestinal pathogenic Escherichia coli (ExPEC) is the leading cause of bacteremia worldwide, with older populations having increased risk of invasive bacterial disease. Increasing resistance to first-line antibiotics and emergence of multidrug-resistant (MDR) strains represent major treatment challenges. ExPEC O serotypes are key targets for potential multivalent conjugate vaccine development. Therefore, we evaluated the O serotype distribution and antibiotic resistance profiles of ExPEC strains causing bloodstream infections across 4 regions. METHODS: Blood culture isolates from patients aged ≥60 years collected during 5 retrospective E. coli surveillance studies in Europe, North America, Asia-Pacific, and South America (2011-2017) were analyzed. Isolates were O serotyped by agglutination; O genotyping was performed for nontypeable isolates. Antimicrobial susceptibility testing was also conducted. RESULTS: Among 3217 ExPEC blood culture isolates, the most ubiquitous O serotype was O25 (n = 737 [22.9%]), followed by O2, O6, O1, O75, O15, O8, O16, O4, O18, O77 group, O153, O9, O101/O162, O86, and O13 (prevalence of ≥1%). The prevalence of these O serotypes was generally consistent across regions, apart from South America; together, these 16 O serotypes represented 77.6% of all ExPEC bacteremia isolates analyzed. The overall MDR frequency was 10.7%, with limited variation between regions. Within the MDR subset (n = 345), O25 showed a dominant prevalence of 63.2% (n = 218). CONCLUSIONS: Predominant O serotypes among ExPEC bacteremia isolates are widespread across different regions. O25 was the most prevalent O serotype overall and particularly dominant among MDR isolates. These findings may inform the design of multivalent conjugate vaccines that can target the predominant O serotypes associated with invasive ExPEC disease in older adults.


Assuntos
Bacteriemia , Infecções por Escherichia coli , Escherichia coli Extraintestinal Patogênica , Humanos , Idoso , Escherichia coli Extraintestinal Patogênica/genética , Escherichia coli , Sorogrupo , Estudos Retrospectivos , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Bacteriemia/epidemiologia , Resistência Microbiana a Medicamentos
7.
Am J Dent ; 36(4): 207-212, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37587032

RESUMO

PURPOSE: To evaluate and compare the effects of different scaling and polishing techniques on the surface roughness of four different restorative materials. METHODS: 72 specimens were prepared, molded to a size of 8.0 by 2.0 mm, and cured according to the manufacturers' instructions. The specimens were stored at 37°C for 24 hours and then thermocycled for 5,000 cycles (from 55°C to 5°C) to simulate 6 months of clinical use. Surface roughness (Ra/average and Rz/max-overall heights) was calculated using a stylus profilometer by subtracting the simulated treatments of hand scaling, ultrasonic scaling, and air polishing from the baseline measurements. The difference in Ra and Rz data were compared independently for each measurement using a two-way ANOVA on Ranks and the Holm-Sidak test, with α< 0.05 used to determine significance. RESULTS: Irrespective of the scaling or polishing technique employed, flowable bulk fill demonstrated the lowest Ra and Rz values. Hand scaling exhibited the highest roughness and variability among the other techniques, regardless of the materials tested (P< 0.001). Air polishing with glycine resulted in the lowest roughness values across all tested materials, with the exception of the tested bioactive restorative material group. CLINICAL SIGNIFICANCE: Regarding surface roughness, air polishing with glycine may be an effective and safe intervention for periodontal maintenance of subgingival restorations compared to the other tested scaling methods.


Assuntos
Materiais Dentários , Raspagem Dentária , Análise de Variância , Glicina , Ultrassom
8.
Am J Dent ; 36(5): 207-212, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37865814

RESUMO

PURPOSE: To compare the microhardness values and bottom/top hardness ratios of different composites after being cured in 2 or 4 mm increments. METHODS: Two bulk fill composites, methacrylate-based and ormocer-based, and one conventional composite were tested. 36 cylindrical discs were prepared (n=12/composite, with six for 2 mm, and six for 4 mm thickness) by pressing each composite into a mold between two glass slides covered by Mylar strips. The top and bottom surfaces of each sample were evaluated using a Buehler hardness tester for Knoop microhardness, with a 50 g static load applied for 10 seconds at three different locations of the central part of each sample. The bottom/top hardness ratio was calculated for each sample. The Knoop microhardness data and bottom/top ratio percentages were analyzed using two-way repeated measures ANOVA and Holm-Sidak post hoc test, with significance at P< 0.05. RESULTS: The tested methacrylate-based bulk fill had the highest overall microhardness among the three tested composites. All three composite types showed a significant difference in microhardness between the top and bottom of the 4 mm discs. The bottom/top ratio percentages differed significantly for both tested bulk fill composites across different thicknesses. Both tested bulk fill materials had a bottom/top ratio of ≥ 80% at the deepest level of a 4 mm increment. CLINICAL SIGNIFICANCE: The type of material significantly affected both the bottom and top microhardness values under the experimental conditions used. While both tested bulk fill composites showed a decline in microhardness at the bottom of the 4 mm depth, they had clinically acceptable microhardness ratios at greater depths.


Assuntos
Resinas Compostas , Metacrilatos , Teste de Materiais , Polimerização , Propriedades de Superfície , Dureza
9.
J Prosthet Dent ; 130(6): 877.e1-877.e7, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37845115

RESUMO

STATEMENT OF PROBLEM: Three-mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP) has been commonly used for fixed prosthodontic restorations. The opacity of 3Y-TZP may be masked with external staining, although the longevity of extrinsic stains applied to monolithic zirconia is unclear. PURPOSE: The purpose of this in vitro study was to analyze the color and surface roughness of extrinsically stained zirconia specimens after thermocycling and toothbrushing. MATERIAL AND METHODS: Monolithic Ø12.5×1.25-mm zirconia disks were milled from 3Y-TZP blocks, sintered according to manufacturer instructions, and then divided into 3 groups (C, J, and O; n=16) for application of stain and glaze. All specimens underwent 10 000 thermocycles in distilled water before being further divided into 2 dentifrice groups (n=8): normal grit, low relative dentin abrasivity (RDA) (Subgroup N) and abrasive grit, high RDA (Subgroup A). Specimens were brushed in a multistation brushing machine under 1.47 N of force using a 5:8 toothpaste and distilled water slurry for 10 000 cycles with a straight (American Dental Association Standard) toothbrush to simulate 1 year of toothbrushing. Color and surface roughness measurements were obtained at 3 time points: baseline, after thermocycling, and after brushing. A 2-way repeated measures ANOVA was used to independently assess changes in color and surface roughness with respect to thermocycling and brushing (α=.05). RESULTS: Group J displayed no significant change in color for either dentifrice system (P>.05). However, a significant change in surface roughness was observed for both dentifrice subgroups (P<.001). Group C specimens displayed significant changes in color (P<.001) and surface roughness (P<.001) for both dentifrice systems. Group O specimens displayed significant changes in color (P<.025) for both dentifrice systems and significant changes in surface roughness (P<.004) for subgroup A, but no significant changes for subgroup N (P=.075). CONCLUSIONS: Artificial aging of monolithic zirconia resulted in changes in color and surface roughness that did not surpass the thresholds for perceptibility and acceptability. This study failed to establish durability limits for extrinsic stains applied to 3Y-TZP.


Assuntos
Dentifrícios , Corantes , Propriedades de Superfície , Teste de Materiais , Zircônio/química , Coloração e Rotulagem , Água , Cerâmica
10.
Popul Health Metr ; 20(1): 14, 2022 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-35597940

RESUMO

BACKGROUND: There is a critical need for maternal and child health data at the local level (for example, county), yet most counties lack sustainable resources or capabilities to collect local-level data. In such case, model-based small area estimation (SAE) could be a feasible approach. SAE for maternal or infant health-related behaviors at small areas has never been conducted or evaluated. METHODS: We applied multilevel regression with post-stratification approach to produce county-level estimates using Pregnancy Risk Assessment Monitoring System (PRAMS) data, 2016-2018 (n = 65,803 from 23 states) for 2 key outcomes, breastfeeding at 8 weeks and infant non-supine sleeping position. RESULTS: Among the 1,471 counties, the median model estimate of breastfeeding at 8 weeks was 59.8% (ranged from 34.9 to 87.4%), and the median of infant non-supine sleeping position was 16.6% (ranged from 10.3 to 39.0%). Strong correlations were found between model estimates and direct estimates for both indicators at the state level. Model estimates for both indicators were close to direct estimates in magnitude for Philadelphia County, Pennsylvania. CONCLUSION: Our findings support this approach being potentially applied to other maternal and infant health and behavioral indicators in PRAMS to facilitate public health decision-making at the local level.


Assuntos
Comportamentos Relacionados com a Saúde , Vigilância da População , Criança , Família , Feminino , Humanos , Lactente , Gravidez , Medição de Risco
11.
Subst Abus ; 43(1): 649-656, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34846993

RESUMO

ABTSTRACTBackground: Opioid misuse during pregnancy has been associated with adverse infant outcomes including preterm birth, stillbirth, and neonatal opioid withdrawal syndrome. The Pregnancy Risk Assessment Monitoring System (PRAMS) is an on-going state-based surveillance system of maternal behaviors, attitudes, and experiences prior to, during, and after pregnancy. Methods: We analyzed qualitative comments related to opioid use during pregnancy collected in 2016 from an open-ended prompt at the end of the PRAMS survey in 35 states (N = 40,408). Key word searches were conducted on the open-ended responses (n = 9,549) to identify opioid-related content with an automated function using Microsoft Excel. All responses from the initial screening (n = 1,035) were manually reviewed, and 69 responses were confirmed to relate to the respondent's personal experience with opioid use during pregnancy. Content analysis was conducted by 3 independent coders; key themes were compiled, discussed, and finalized by the coding team. Results: Five key themes related to opioid use during pregnancy were identified: (1) gratitude for treatment, recovery, and healthy infants; (2) pregnancy as motivation to seek treatment; (3) difficulty finding prenatal care providers with training in substance use disorders; (4) concern about the effects of treatment on the infant; and (5) experiences of discrimination and stigma in the hospital around the time of delivery. Conclusions: Women may be aware of the potential impact of opioid use during pregnancy on the health of their infants and motivated to seek treatment. Findings may help inform new and ongoing initiatives designed to improve care and reduce stigma for women needing or seeking treatment.


Assuntos
Transtornos Relacionados ao Uso de Opioides , Nascimento Prematuro , Analgésicos Opioides/efeitos adversos , Feminino , Humanos , Recém-Nascido , Vigilância da População , Gravidez , Medição de Risco , Inquéritos e Questionários
12.
J Arthroplasty ; 37(6S): S355-S363, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35219574

RESUMO

BACKGROUND: Patients have received cobalt-chromium-molybdenum (CoCrMo) implants for their joint replacement for decades. There have been reports of inflammatory cell-induced corrosion (ICIC) of these implants from retrieval studies. The goal of this study is to see if we could recreate ICIC in vitro and whether electrocautery damage to alloy surfaces may hasten this process. METHODS: Murine macrophages were cultured on CoCr disks with and without damage from a monopolar electrocautery. Culture medium was replaced every 12 hours and supernatant was collected every 4 days. After 30 days, cells were removed, counted, and digested. The metal concentrations in the supernatant and within cells were assessed using inductively coupled plasma spectrometry for comparison. RESULTS: The Co supernatant concentration was higher in the undamaged disks with activated macrophages. Higher concentrations of Co and Mo were found in the supernatant of the undamaged disks vs the electrocautery (EC) corrosion damaged disks. There was a significantly higher intracellular Co and Mo concentration with activated cells on CoCrMo disks vs the control group and no difference compared to EC damaged disk group. Scanning electron microscopy displayed microscopic pitting on the surfaces exposed to macrophages without EC damage. CONCLUSION: We found that macrophages could reproduce findings of ICIC pits on the surface of CoCrMo alloy and that the addition of EC damage to the surface did not increase the process. The clinical significance of these findings should be further investigated to determine if this could explain a small number of poor total knee arthroplasty reported outcomes.


Assuntos
Artroplastia do Joelho , Vitálio , Ligas , Animais , Cromo , Cobalto/química , Corrosão , Humanos , Macrófagos , Camundongos
13.
Am J Dent ; 35(2): 161-164, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35798712

RESUMO

PURPOSE: To evaluate the laboratory long-term effect of various whitening dentifrices on the surface roughness of two brands of resin composite (TPH ST, Filtek Bulk Fill One) using a mechanical toothbrushing simulation. METHODS: Thirty-two samples each of Filtek and TPH were fabricated in ring molds 10 x 1 mm. Samples were randomly grouped (n=8; four groups), according to dentifrice used; Crest 3D, Optic White, Hello (charcoal), and Aim as control. Samples were brushed in mixed solutions containing deionized water and dentifrice at 150 gf for 10,000x with rotation to ensure uniform brushing. Surface roughness was measured both before (baseline) and after the mechanical toothbrushing simulation using a stylus profilometer. Data collected was compared independently for each treatment using two-way ANOVA and SNK with α< 0.05 for significance. RESULTS: The data showed that TPH was more susceptible to the abrasive nature of three of the whitening dentifrices tested [Crest 3D, Optic White, and Hello (charcoal) ]. Filtek also exhibited significant susceptibility to the abrasive nature of Hello. Aim showed the least or minimal amount of abrasion. CLINICAL SIGNIFICANCE: TPH ST composite was more susceptible to the abrasive nature of the three whitening dentifrices tested [Crest 3D, Optic White, and Hello (charcoal)]. Filtek also exhibited significant susceptibility to the abrasive nature of Hello. Aside from the data supporting the clinical efficacy of TPH compared to Filtek, clinicians should inform patients of the abrasive capacity of all whitening dentifrices, especially those that are charcoal based.


Assuntos
Dentifrícios , Carvão Vegetal , Humanos , Propriedades de Superfície , Escovação Dentária
14.
J Prosthodont ; 31(8): 705-713, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34942682

RESUMO

PURPOSE: To investigate the potential of adding silver-nanoparticle-containing amorphous calcium phosphate microparticles as bioactive fillers into commercially available nonbioactive dental resin cement. MATERIALS AND METHODS: Experimental cement was formulated by adding 7.5% silver-nanoparticle-containing amorphous calcium phosphate microparticles to Multilink Automix resin cement (Ivoclar Vivadent). The experimental cement was evaluated for shear bond strength (N = 11 per group) and demineralization/remineralization (N = 16 per group), with BioCem® Universal BioActive cement (NuSmile) as the positive control and Multilink Automix cement as the negative control. One-way analysis of variance and post hoc tests were used to assess the significance of differences among or between the groups RESULTS: The addition of silver-nanoparticle-containing amorphous calcium phosphate microparticles at the level of 7.5% by weight into Multilink Automix did not have a statistically significant effect on the shear bond strength (p > 0.05), but statistically significantly increased the depth of remineralization on both dentin and enamel (p = 0.01 and p < 0.001, respectively) when compared to Multilink Automix alone. The experimental cement prepared in the present study was comparable to BioCem® on the depths of remineralization on both dentin and enamel (p = 0.59 and p = 0.99, respectively). CONCLUSION: When incorporated into nonbioactive commercial dental resin cements as bioactive fillers at the level of 7.5% by weight, silver-nanoparticle-containing amorphous calcium phosphate microparticles could provide remineralization potential without affecting the shear bond strength.


Assuntos
Colagem Dentária , Cimentos de Resina , Cimentos de Resina/uso terapêutico , Cimentos de Resina/química , Cimentos Dentários/uso terapêutico , Cimentos Dentários/química , Prata/farmacologia , Prata/uso terapêutico , Teste de Materiais , Cimentos de Ionômeros de Vidro , Materiais Dentários , Resistência ao Cisalhamento , Propriedades de Superfície , Análise do Estresse Dentário
15.
J Arthroplasty ; 36(3): 1126-1132, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33067092

RESUMO

BACKGROUND: Pitting damage on implants has been reported and attributed to the use of electrocautery. This study aimed to determine how different total knee arthroplasty bearing surfaces are susceptible to this type of damage and whether surgeons are aware that this damage can occur. METHODS: A survey was sent to Hip and Knee Society members to determine what percentage of adult reconstructive surgeons use electrocautery after implantation of components. Three bearing surfaces for total knee arthroplasty were selected: cobalt chromium, Oxinium, and zirconium nitride to be damaged by electrocautery with a monopolar (MP) and bipolar (BP) electrocautery with 3 different energy settings. A comparison of surface damage using scanning electron microscopy and elemental differences using energy dispersion spectroscopy was performed. Average roughness (Ra), maximal peak-to-valley height (Rz), kurtosis (Rk), and skewness (Rsk) were recorded for comparison using a profilometer was performed. RESULTS: Median Rz and Ra measurements were larger for BP damaged areas compared to MP for all bearing surfaces. The Oxinium surface had the greatest increase in roughness parameters. Survey results indicate that a significant percentage of adult reconstructive surgeons use the electrocautery after implants are in place and are not aware of this type of damage. Backscatter scanning electron microscopy analysis found significant changes for BP damage compared to MP. CONCLUSION: Surface damage caused by electrocautery can have significant effects on the bearing surfaces of implants but further study needs to be performed to determine if this is a clinical issue. Our survey determined that many arthroplasty experts are unaware that this damage can occur.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Adulto , Artroplastia do Joelho/efeitos adversos , Ligas de Cromo , Eletrocoagulação/efeitos adversos , Humanos , Articulação do Joelho/cirurgia , Prótese do Joelho/efeitos adversos , Desenho de Prótese
16.
Am J Dent ; 34(5): 240-244, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34689445

RESUMO

PURPOSE: To evaluate color and gloss changes of three different resin composites after staining and whitening. METHODS: 57 disc-shaped composite samples were made for each of three resin composite materials [Activa BioActive Restorative (Activa), Filtek Supreme (Filtek), and TPH Spectra (TPH)], producing 19 samples per composite (n=19). Each group of resin samples was divided among four solutions: red wine, coffee, tea, and water (control), producing six samples per staining group (n=6) and one control (n=1). Samples were stained for 40 days for 3 hours/day at room temperature. When not undergoing staining/whitening, samples were stored in DI water at 37°C. Measurements were obtained for color and gloss before staining, after staining, and after whitening. Illuminant source specular component excluded (SCE) and included (SCI), with both CIE L*a*b* and CIE 2000 L*C*h* systems, were obtained with colorimetric measurements. The standard ΔE (total color change) = 3.3 was used as a clinically acceptable value. Stained groups were divided into two groups (n= 9 each) for each whitening product: Opalescence Boost and Opalescence PF. Both were applied according to manufacturer's instructions. RESULTS: Staining of all samples consistently showed decreased lightness. Filtek showed the most colorimetric changes, especially with wine, while TPH and Activa composites showed few changes; most changes were with tea. Whitening altogether showed generalized increased lightness. All Activa specimens returned to clinically acceptable levels, but the other two materials tested varied. Gloss was most affected for TPH, followed by Filtek; and gloss improved with Activa groups. Overall, Filtek's color varied most, with Activa and TPH being less. All Activa groups returned to clinically acceptable values. However, multiple TPH and Filtek groups had ΔE> 3.3. Furthermore, TPH had the most gloss changes. Activa composites appeared the most stable under the conditions of this study. CLINICAL SIGNIFICANCE: Clinicians should be aware that resin composites can undergo staining from a variety of sources. Some resin composites can return to their original esthetic appearance after using bleaching agents. In addition, staining beverages can affect the gloss of the resin composite.


Assuntos
Café , Água , Cor , Coloração e Rotulagem
17.
J Prosthodont ; 30(3): 245-251, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32869384

RESUMO

PURPOSE: To determine the efficacy of various finishing and polishing techniques on the surface roughness of two computer-aided design/computer-aided manufacturing (CAD/CAM) materials, lithium disilicate (IPS e.max), lithium disilicate reinforced with lithium aluminosilicate (Straumann® n!ce™), and a stackable low-fusing nanofluorapatite glass ceramic (Ceram). MATERIALS AND METHODS: Flat specimens (n = 12) per treatment group were fabricated 2 mm thick, 15 mm in length, and 12mm in width. Samples were either glazed or polished. Glazing was accomplished with either Ivoclar IPS e.max CAD crystall glaze spray or IPS e.max Ceram glaze paste, according to manufacturer instructions. Three different polishing systems were tested: Brasseler Dialite HP, Ivoclar OptraFine, and Komet LD/ZR. Polishing was performed using a Kavo adjustable slow speed electric contra-angle handpiece mounted to an oscillating Toothbrush Dentifrice Assessment Instrument. Surface roughness data was collected using a benchtop stylus profilometer and analyzed for statistical significance using two-way ANOVA (α = 0.05). Representative scanning electron micrograph images were generated for all samples. RESULTS: Overall there was no significant difference in Ra when comparing types of ceramic (p = 0.9315, F = 0.071). However, there was a statistically significant difference when comparing groups of finishing treatments (p < 0.001, F = 113.5) and also when comparing finishing treatment with ceramic type (p < 0.001, F = 11.13). No significant difference was found with IPS e.max CAD crystall glaze spray on Straumann® n!ce™ versus IPS e.max Ceram glaze paste on IPS e.max Ceram (p = 0.8745) or IPS e.max CAD crystall glaze spray on IPS e.max versus IPS e.max Ceram glaze paste on IPS e.max Ceram (p = 0.3373). Significant differences in Ra of Straumann® n!ce™ were found when comparing Brasseler with Ivoclar (p = 0.0014) and Ivoclar with Komet (p = 0.047). No significant difference was observed between Brasseler and Komet (p = 0.8099). CONCLUSIONS: It appears that the degree of surface roughness depends upon the specific finishing system and ceramic combination used. Straumann® n!ce™ is more efficiently polished using Brasseler Dialite HP or Komet LD/ZR polishing systems. Ivoclar crystal glaze spray was found to be equally as effective on Straumann® n!ce™ and IPS e.max as IPS e.max Ceram glaze paste on IPS e.max Ceram.


Assuntos
Cerâmica , Porcelana Dentária , Desenho Assistido por Computador , Polimento Dentário , Teste de Materiais , Polônia , Propriedades de Superfície
18.
MMWR Morb Mortal Wkly Rep ; 69(28): 897-903, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32673301

RESUMO

BACKGROUND: Prescription opioid use during pregnancy has been associated with poor outcomes for mothers and infants. Studies using administrative data have estimated that 14%-22% of women filled a prescription for opioids during pregnancy; however, data on self-reported prescription opioid use during pregnancy are limited. METHODS: CDC analyzed 2019 data from the Pregnancy Risk Assessment Monitoring System (PRAMS) survey in 32 jurisdictions and maternal and infant health surveys in two additional jurisdictions not participating in PRAMS to estimate self-reported prescription opioid pain reliever (prescription opioid) use during pregnancy overall and by maternal characteristics among women with a recent live birth. This study describes source of prescription opioids, reasons for use, want or need to cut down or stop use, and receipt of health care provider counseling on how use during pregnancy can affect an infant. RESULTS: An estimated 6.6% of respondents reported prescription opioid use during pregnancy. Among these women, 21.2% reported misuse (a source other than a health care provider or a reason for use other than pain), 27.1% indicated wanting or needing to cut down or stop using, and 68.1% received counseling from a provider on how prescription opioid use during pregnancy could affect an infant. CONCLUSIONS AND IMPLICATIONS FOR PUBLIC HEALTH PRACTICE: Among respondents reporting opioid use during pregnancy, most indicated receiving prescription opioids from a health care provider and using for pain reasons; however, answers from one in five women indicated misuse. Improved screening for opioid misuse and treatment of opioid use disorder in pregnant patients might prevent adverse outcomes. Implementation of public health strategies (e.g., improving state prescription drug monitoring program use and enhancing provider training) can support delivery of evidence-based care for pregnant women.


Assuntos
Analgésicos Opioides/uso terapêutico , Dor Crônica/tratamento farmacológico , Medicamentos sob Prescrição/uso terapêutico , Adolescente , Adulto , Analgésicos Opioides/efeitos adversos , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Educação de Pacientes como Assunto/estatística & dados numéricos , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Uso Indevido de Medicamentos sob Prescrição/estatística & dados numéricos , Medicamentos sob Prescrição/efeitos adversos , Medição de Risco , Autorrelato , Estados Unidos/epidemiologia , Adulto Jovem
19.
Am J Dent ; 33(2): 69-73, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32259410

RESUMO

PURPOSE: To evaluate marginal seal, adaptation, surface texture, and bubble presence of pit and fissure sealants when using a novel instrument (C-Shape It) or the manufacturers' supplied applicators for sealant placement into occlusal fissures. METHODS: Extracted molars with occlusal fissures were cleaned with pumice slurry and divided into six groups (n= 10/gp); three treatment and three control. Sealant materials placed included Ultraseal, Delton, and Helioseal. Excess water was removed per manufacturers' instructions. Sealants were applied with each applicator and with the C-Shape It to each group from cusp to cusp without covering marginal ridges, and the polymerization guidelines for photocuring were followed for all the groups. Samples were thermocycled at 500x between 5° and 55°C. Teeth were sectioned in a buccolingual direction with a minimum of four sections per tooth and examined under a light microscope at 50x and scored. RESULTS: Marginal seal, adaptation, penetration ability, surface texture, bubble formation and location of the sealants were analyzed using two-way ANOVA on ranks with a 95% confidence interval. The C-Shape It instrument showed consistently smoother surface texture (P< 0.001), which was statistically significant versus all manufacturers' applicators for all materials. Bubble presence was statistically significantly less with the instrument C-Shape It versus the manufacturers' applicators for all materials (P< 0.001). Results also revealed significant differences in marginal sealant adaptation. CLINICAL SIGNIFICANCE: C-Shape It demonstrated consistent ability to reduce bubbles and improve surface texture and adaptation in occlusal fissures for all pit and fissure products tested.


Assuntos
Infiltração Dentária , Selantes de Fossas e Fissuras , Bis-Fenol A-Glicidil Metacrilato , Dente Molar
20.
Gen Dent ; 68(3): 51-56, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348244

RESUMO

Low-viscosity polymer resins, or surface sealants (SSs), have been utilized as a means of finalizing the polishing step following the placement of composite resin restorations. The aim of this study was to measure the surface roughness (Ra) of composite resins treated with different SSs before and after exposure to an accelerated artificial aging protocol. The study included 5 experimental groups of composite resin discs (TPH Spectra ST) treated with different SSs (PermaSeal, Embrace WetBond Seal-n-Shine, OptiGuard, BisCover LV, and DuraFinish) and a control group consisting of untreated discs (n = 6 per group). The discs were prepared by inserting composite resin in 10 × 1-mm rings, covering the ring and material with a transparent strip, compressing the assembly between glass slides, and polymerizing through the slides on each side for 40 seconds with an LED curing light. Each disc except for the control specimens received a coating of the selected SS followed by application of a transparent matrix strip and then light polymerization for 20 seconds using an LED light source. Surface roughness measurements were obtained with a digital contact profilometer at baseline (immediately after polymerization) and following exposure to a thermocycling regimen to simulate aging. The data were analyzed using 2-way analysis of variance and post hoc Student-Newman-Keuls test with significance set at P < 0.05. There were no statistically significant differences among the groups at baseline. There were no statistically significant differences between the baseline and post-thermocycling Ra measurements except among the DuraFinish specimens, which were significantly rougher than all other groups after accelerated artificial aging. The use of SSs for the initial insertion and possibly for the long-term maintenance of composite resins could be minimally beneficial for restoration maintenance if a transparent covering medium is utilized during polymerization. However, due to the effects caused by formation of an oxygen-inhibited layer of unpolymerized monomers if a covering medium is not used, the results suggest the benefits do not offset the costs considering both gloss and Ra surface-testing parameters.


Assuntos
Resinas Compostas , Polimento Dentário , Humanos , Teste de Materiais , Propriedades de Superfície
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