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1.
Sci Rep ; 14(1): 15206, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956329

RESUMO

The study investigated the effects of temperature and centrifugation time on the efficacy of removing uncured resin from 3D-printed clear aligners. Using a photo-polymerizable polyurethane resin (Tera Harz TC-85, Graphy Inc., Seoul, Korea), aligners were printed and subjected to cleaning processes using isopropyl alcohol (IPA) or centrifugation (g-force 27.95g) at room temperature (RT, 23 °C) and high temperature (HT, 55 °C) for 2, 4, and 6 min. The control group received no treatment (NT). Cleaning efficiency was assessed through rheological analysis, weight measurement, transparency evaluation, SEM imaging, 3D geometry evaluation, stress relaxation, and cell viability tests. Results showed increased temperature and longer centrifugation times significantly reduced aligner viscosity, weight (P < 0.05), and transmittance. IPA-cleaned aligners exhibited significantly lower transparency and rougher surfaces in SEM images. All groups met ISO biocompatibility standards in cytotoxicity tests. The NT group had higher root mean square (RMS) values, indicating greater deviation from the original design. Stress relaxation tests revealed over 95% recovery in all groups after 60 min. The findings suggest that a 2-min HT centrifugation process effectively removes uncured resin without significantly impacting the aligners' physical and optical properties, making it a clinically viable option.


Assuntos
Centrifugação , Impressão Tridimensional , Temperatura , Resinas Sintéticas/química , Poliuretanos/química , Sobrevivência Celular/efeitos dos fármacos , Teste de Materiais , Humanos , Animais
2.
Int J Med Inform ; 191: 105543, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39084087

RESUMO

INTRODUCTION: Preparing appropriate red blood cells (RBCs) before surgery is crucial for improving both the efficacy of perioperative workflow and patient safety. In particular, thoracic surgery (TS) is a procedure that requires massive transfusion with high variability for each patient. Hence, the precise prediction of RBC requirements for individual patients is becoming increasingly important. This study aimed to 1) develop and validate a machine learning algorithm for personalized RBC predictions for TS patients and 2) assess the usability of a clinical decision support system (CDSS) integrating this artificial intelligence model. METHODS: Adult patients who underwent TS between January 2016 and October 2021 were included in this study. Multiple models were developed by employing both traditional statistical- and machine-learning approaches. The primary outcome evaluated the model's performance in predicting RBC requirements through root mean square error and adjusted R2. Surgeons and informaticians determined the precision MSBOS-Thoracic Surgery (pMSBOS-TS) algorithm through a consensus process. The usability of the pMSBOS-TS was assessed using the System Usability Scale (SUS) survey with 60 clinicians. RESULTS: We identified 7,843 cases (6,200 for training and 1,643 for test sets) of TSs. Among the models with variable performance indices, the extreme gradient boosting model was selected as the pMSBOS-TS algorithm. The pMSBOS-TS model showed statistically significant lower root mean square error (mean: 3.203 and 95% confidence interval [CI]: 3.186-3.220) compared to the calculated Maximum Surgical Blood Ordering Schedule (MSBOS) and a higher adjusted R2 (mean: 0.399 and 95% CI: 0.395-0.403) compared to the calculated MSBOS, while requiring approximately 200 fewer packs for RBC preparation compared to the calculated MSBOS. The SUS score of the pMSBOS-TS CDSS was 72.5 points, indicating good acceptability. CONCLUSIONS: We successfully developed the pMSBOS-TS capable of predicting personalized RBC transfusion requirements for perioperative patients undergoing TS.

3.
Dent Mater ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39068090

RESUMO

OBJECTIVES: This study aimed to use a carboxybetaine methacrylate (CBMA) copolymer solution to surface treat 3D printed clear aligners at different fabrication stages, to impart antifouling properties, and assess the surface treatment at various fabrication stages' impact on physico-mechanical characteristics. METHODS: Surface treatments using a blend of 2-hydroxyethyl methacrylate (HEMA) and CBMA, termed CCS, were performed at various stages of 3D printed clear aligner fabrication. Experimental groups, CB1, CB2, and CB3, were determined by the stage of surface treatment during post-processing. CB1, CB2, and CB3 received treatment before post-curing, after post-curing, and after post-processing, respectively. Untreated samples served as controls. Physical and mechanical properties were assessed through tensile testing, Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and UV-Vis spectroscopy. The surface was further characterized through scanning electron microscopy and contact angle measurements. The cytotoxicity was assessed with 7-day elution and agar diffusion assays. Lastly, bacterial biofilm resistance was evaluated using confocal laser scanning microscopy. Crystal violet assay was performed using Streptococcus mutans. RESULTS: Surface treatment during CB1 stage exerted the most significantly unfavorable influence on properties of the 3D printed aligner resin. CB2 samples showed the maximum preservation of translucency even after 7-day aging. CB2 and CB3 phases showed enhanced hydrophilicity of sample surfaces with reduced adhesion of multispecies biofilm and S. mutans. SIGNIFICANCE: Application of CCS surface treatment immediately after post-curing (CB2) can enhance the biofilm resistance of 3D printed clear aligners while maintaining high fidelity to optical translucency and constituent mechanical properties.

4.
J Dent ; 148: 105054, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38796091

RESUMO

OBJECTIVES: To create bacteria-resistant dental CAD-CAM blocks with a biofilm-resistant effect by incorporating Nano-crystalline ceramic and polymer (NCP) with 2-methacryloyloxyethyl phosphorylcholine (MPC) and sulfobetaine methacrylate (SBMA) and at an equimolar ratio, referred to as MS. METHODS: Experimental groups comprised NCP blocks containing zwitterions at 0.15wt% (MS015) and 0.45wt% (MS045). NCP blocks without MS served as control (CTRL). Flexural strength, surface hardness, water sorption and solubility, photometric properties, and cytotoxicity were assessed for all samples. Additionally, the resistance to single and multi-species bacterial adhesion was investigated. RESULTS: MS045 showed significant reduction in flexural strength (P < 0.01) compared to both CTRL and MS015. Both MS015 and MS045 showed significantly increased water sorption and significant reduction in water solubility compared to CTRL. Light transmission remained consistent across all MS content levels, but the irradiance value decreased by 12 % in the MS045 group compared to the MS015 group. Notably, compared to the CTRL group, the MS015 group exhibited enhanced resistance to adhesion by Porphyromonas gingivalis and a multi-species salivary biofilm, with biofilm thickness and biomass reduced by 45 % and 56 %, respectively. CONCLUSIONS: NCP containing 0.15 % MS can effectively reduce adhesion of multiple species of bacteria while maintaining physical and mechanical properties. CLINICAL SIGNIFICANCE: NCP integrating zwitterions is clinically advantageous in resisting bacterial adhesion at internal and external margins of milled indirect restoration.


Assuntos
Aderência Bacteriana , Biofilmes , Cerâmica , Desenho Assistido por Computador , Resistência à Flexão , Teste de Materiais , Metacrilatos , Fosforilcolina , Propriedades de Superfície , Cerâmica/química , Metacrilatos/química , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Fosforilcolina/farmacologia , Materiais Dentários/química , Polímeros/química , Humanos , Dureza , Solubilidade , Porphyromonas gingivalis/efeitos dos fármacos
5.
J Clin Pharmacol ; 64(7): 849-859, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38436463

RESUMO

Delpazolid (LCB01-0371) is a novel oxazolidinone derivative with a good safety profile for treating gram-positive pathogenic infections such as Mycobacterium abscessus, a highly pathogenic drug-resistant Mycobacterium. In this study, we evaluated the pharmacokinetics (PK) and pharmacodynamics (PD) of delpazolid after 14 days of multiple oral administration, using data from adult patients with pulmonary tuberculosis. 800 mg once a day, 400 mg twice a day, 800 mg twice a day, and 1200 mg once a day delpazolid for 14 days were tested in 63 patients with pulmonary tuberculosis. For PK blood collection, inpatient and outpatient scheduling were separately implemented. Plasma concentrations of delpazolid were measured at visits 2, 4, 6, and 8 in outpatients, and four sparse blood samples were measured in inpatients. PD models were sequentially fitted using individual PK parameter estimates obtained from PK compartmental models. For PK modeling, 180 plasma concentrations of delpazolid from 56 patients were included. A two-compartment mixed first- and zero-order absorption model best described the time course of plasma concentration. For the PD model, 448 bacterial titer data from 60 patients were used. The time course of bacterial titers (log10 CFU/mL) was described by a model that consists of the growth and killing rate of bacteria with the sigmoid Emax model. The PK-PD simulation suggested that the bacterial titers are the lowest on the 800 mg bid regimen among the four, consistent with observed data, as all regimens substantially decrease. In the dose-response relationship, the effectiveness of delpazolid was suggested.


Assuntos
Modelos Biológicos , Oxazolidinonas , Tuberculose Pulmonar , Humanos , Masculino , Feminino , Oxazolidinonas/farmacocinética , Oxazolidinonas/administração & dosagem , Oxazolidinonas/uso terapêutico , Adulto , Pessoa de Meia-Idade , Tuberculose Pulmonar/tratamento farmacológico , Idoso , Antituberculosos/farmacocinética , Antituberculosos/uso terapêutico , Antituberculosos/administração & dosagem , Adulto Jovem , Relação Dose-Resposta a Droga , Administração Oral
6.
J Mech Behav Biomed Mater ; 151: 106399, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38244423

RESUMO

Calcium silicate-based cement (CSC) is a commonly used material in endodontic treatment. However, it has limited antibacterial activity, especially for cases involving primary infections. Zinc oxide nanoparticles (ZnO-NPs) are recognized for their potential in biomedical applications due to their antibacterial properties and ability to reduce inflammation. This study aims to optimize CSC by incorporating ZnO-NPs to maintain its physical properties, enhance its antibacterial activity, and reduce the production of pro-inflammatory cytokines. ZnO-NPs were integrated into a commercial CSC (Endocem MTA) at 1 wt% (CSZ1) or 3 wt% (CSZ3). Setting time, compressive strength, and X-ray diffraction were then measured. In addition, pH, calcium ion release, and zinc ion release were measured for 7 days. Antibacterial activity against Enterococcus faecalis and viability of murine macrophages (RAW264.7) were determined using colorimetric assays. Gene expression levels of pro-inflammatory cytokines in lipopolysaccharide induced RAW264.7 were evaluated using quantitative polymerase chain reaction. Results were compared to an unmodified CSC group. In the CSZ3 group, there was a significant increase of approximately 12% in setting time and a reduction of about 36.4% in compressive strength compared to the control and CSZ1 groups. The presence of ZnO-NPs was detected in both CSZ1 and CSZ3. Both CSC and CSZ1 groups maintained an alkaline pH and released calcium ions, while zinc ions were significantly released in the CSZ1 group. Additionally, CSZ1 showed a 1.8-fold reduction of bacterial activity and exhibited around 85% reduction in colony-forming units compared to the CSC group. Furthermore, the CSZ1 group showed a more than 39% reduction in pro-inflammatory cytokine levels compared to the CSC group. Thus, enriching CSC with 1 wt% ZnO-NPs can enhance its antibacterial activity and reduce pro-inflammatory cytokines without showing any tangible adverse effects on its physical properties.


Assuntos
Compostos de Cálcio , Nanopartículas , Silicatos , Óxido de Zinco , Animais , Camundongos , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Óxidos/química , Cálcio , Nanopartículas/química , Antibacterianos/farmacologia , Zinco , Citocinas
7.
Sci Rep ; 13(1): 17763, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853055

RESUMO

Dental composite resins are widely used in dental restorations. However, their clinical application is limited by the occurrence of secondary caries. Strontium-modified phosphate-based glass (Sr-PBG) is a material known to have a sustainable bacterial resistance effect. The mechanical properties (in particular, flexural strength, modulus of elasticity, and hardness) of dental materials determine their function. Therefore, this study aimed to investigate the mechanical and ion-releasing properties as well as the sustainable bacterial resistance effect of bioactive resin composites containing Sr-PBG. The data were analyzed by ANOVA and Tuckey's tests (p < 0.05). We incorporated a Sr-PBG microfiller at 3, 6, and 9 wt.% concentrations into a commercially available composite resin and investigated the mechanical properties (flexural strength, elastic modulus, and micro hardness), ion release characteristics, and color of the resultant resins. In addition, we examined the antibacterial effects of the composite resins against Streptococcus mutans (S. mutans). The mechanical properties of the Sr-PBG groups differed only slightly from those of the control group (p > 0.05). However, the optical density at 600 nm of S. mutans incubated on the experimental group was significantly lower compared to that observed with the control (p < 0.05) both before and after thermocycling between 5 and 55 â„ƒ for 850 cycles (dwell time: 45 s). Therefore, strontium-modified resin materials exhibited a sustainable bacterial resistance effect in vitro while maintaining some of the mechanical properties of ordinary acrylic resins.


Assuntos
Resinas Compostas , Metacrilatos , Teste de Materiais , Vidro , Elasticidade , Propriedades de Superfície
8.
J Dent ; 137: 104689, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37666468

RESUMO

OBJECTIVES: This study aimed at demonstrating the remineralization effect of the enamel around the brackets to aid reduction in white spot lesions (WSLs) with use of zinc-doped phosphate-based glass (Zn-PBG) containing orthodontic adhesives. METHODS: Zn-PBG powder was synthesized, and particle morphology, size, and density were evaluated. Orthodontic adhesives with increasing loading percentage of Zn-PBG powder were prepared: ZnPG3 (3 wt.%), ZnPG6 (6 wt.%), and ZnPG9 (9 wt.%). Brackets were bonded on the etched enamel surface and stored in distilled water (DW) for 1 h. Following, Shear bond strength (SBS) along with adhesive remnant index were analyzed. The release of calcium (Ca), phosphorus (P), and zinc (Zn) from adhesive specimens in DW was evaluated after 7, 15 and 30 days of immersion. The remineralization effect was confirmed by microhardness and surface morphology analysis with scanning electron microscopy. RESULTS: The SBS value was observed between 20 and 22 MPa on enamel surface. The concentration of Ca, P and Zn released in DW increased with loading percentage of Zn-PBG. The microhardness increased in the experimental groups after immersion in artificial saliva for 7 days. Apatite-like crystal formation was observed after 30 days in the ZnPG 9 group. CONCLUSIONS: The orthodontic adhesive containing Zn-PBG with an optimal SBS performance has an enamel remineralization effect, and therefore can aid in prevention of WSLs. CLINICAL SIGNIFICANCE: The orthodontic adhesive containing Zn-PBG is clinically advantageous as it can promote remineralization and resist the formation of WSLs that may occur during orthodontic therapy.


Assuntos
Cárie Dentária , Cimentos Dentários , Humanos , Pós , Fosfatos , Cálcio
9.
Biomater Sci ; 11(18): 6299-6310, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37551440

RESUMO

Phosphate-based glass (PBG) is a bioactive agent, composed of a glass network with phosphate as the primary component and can be substituted with various therapeutic ions for functional enhancement. Strontium (Sr) has been shown to stimulate osteogenic activity and inhibit pro-inflammatory responses. Despite this potential, there are limited studies that focus on the proportion of Sr substituted and its impact on the functional activity of resulting Sr-substituted PBG (PSr). In this study, focusing on the cellular biological response we synthesized and investigated the functional activity of PSr by characterizing its properties and comparing the effect of Sr substitution on cellular bioactivity. Moreover, we benchmarked the optimal composition against 45S5 bioactive glass (BG). Our results showed that PSr groups exhibited a glass structure and phosphate network like that of PBG. The release of Sr and P was most stable for PSr6, which showed favorable cell viability. Furthermore, PSr6 elicited excellent early osteogenic marker expression and inhibition of pro-inflammatory cytokine expression, which was significant compared to BG. In addition, compared to BG, PSr6 had markedly higher expression of osteopontin in immunocytochemistry, higher ALP expression in osteogenic media, and denser alizarin red staining in vitro. We also observed a comparable in vivo regenerative response in a 4-week rabbit calvaria defect model. Therefore, based on the results of this study, PSr6 could be identified as the functionally optimized composition with the potential to be applied as a valuable bioactive component of existing biomaterials used for bone regeneration.


Assuntos
Regeneração Óssea , Osteogênese , Animais , Coelhos , Linhagem Celular , Fosfatos , Estrôncio/farmacologia , Estrôncio/química , Vidro/química
11.
Sci Rep ; 13(1): 3589, 2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36869063

RESUMO

Biofilms induce microbial-mediated surface roughening and deterioration of cement. In this study, zwitterionic derivatives (ZD) of sulfobetaine methacrylate (SBMA) and 2-methacryloyloxyethyl phosphorylcholine, were added in concentrations of 0, 1, and 3% to three different types of commercially available resin-modified glass ionomer cement (RMGIC) (RMC-I: RelyX Luting 2, RMC-II: Nexus RMGI, and RMC-III: GC FujiCEM 2). The unmodified RMGICs served as the control group for comparison. The resistance of Streptococcus mutans to ZD-modified RMGIC was evaluated with a monoculture biofilm assay. The following physical properties of the ZD-modified RMGIC were assessed: wettability, film thickness, flexural strength, elastic modulus, shear bond strength, and failure mode. The ZD-modified RMGIC significantly inhibited biofilm formation, with at least a 30% reduction compared to the control group. The addition of ZD improved the wettability of RMGIC; however, only 3% of the SBMA group was statistically different (P < 0.05). The film thickness increased in proportion to the increasing ZD concentrations; there was no statistical difference within the RMC-I (P > 0.05). The experimental groups' flexural strength, elastic modulus, and shear bond strength showed an insignificant decrease from the control group; there was no statistical difference within the RMC-I (P > 0.05). The mode of failure differed slightly in each group, but all groups showed dominance in the adhesive and mixed failure. Thus, the addition of 1 wt.% ZD in RMGIC favorably enhanced the resistance to Streptococcus mutans without any tangible loss in flexural and shear bond strength.


Assuntos
Resinas Acrílicas , Betaína , Cimentos de Ionômeros de Vidro
12.
Ann Pediatr Endocrinol Metab ; 28(4): 296-301, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36758973

RESUMO

PURPOSE: We sought to investigate the effects and side effects of once-weekly dulaglutide treatment for type 2 diabetes mellitus (T2DM) in patients <18 years of age in Korea. METHODS: : From the Eulji University Hospital database, we identified all patients <18 years of age diagnosed with T2DM and treated with dulaglutide from January 1, 2017, to July 31, 2022. RESULTS: We identified 5 patients <18 years of age treated with dulaglutide for T2DM management. Their mean (standard deviation [SD]) age was 16.6 (0.5) years. Four (80%) patients were female. The mean (SD) body mass index was 29.4 (5.1) kg/m2, and the mean (SD) age at diagnosis was 15.2 (1.6) years. Four patients had been treated previously with metformin alone or in combination with insulin. Four patients were treated with 1.5 mg of dulaglutide and one was treated with 0.75 mg of dulaglutide. The mean (SD) hemoglobin A1c concentrations at baseline, 3 months after treatment, and 1 year after treatment, respectively, were 10.0% (2.2%), 6.5% (1.5%), and 6.7% (1.4%), with significant differences. In addition, at baseline, 3 months after treatment, and 1 year after treatment, the mean (SD) body weight values were 79.7 (13.3) kg, 80.2 (14.0) kg, and 81.1 (15.3) kg, with no significant difference. CONCLUSION: Use of once-weekly dulaglutide for juvenile T2DM ensures very good glycemic control, with few side effects and good adherence, indicating its potential as a promising therapeutic agent in this age group. Nationwide studies are warranted to confirm our results.

13.
Biomaterials ; 296: 122063, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36848780

RESUMO

Poly-(methyl methacrylate) (PMMA) is the preferred biomaterial for orofacial prostheses used for the rehabilitation of naso-palatal defects. However, conventional PMMA has limitations determined by the complexity of the local microbiota and the friability of oral mucosa adjacent to these defects. Our purpose was to develop a new type of PMMA, i-PMMA, with good biocompatibility and better biological effects such as higher resistance to microbial adhesion of multiple species and enhanced antioxidant effect. The addition of cerium oxide nanoparticles to PMMA using a mesoporous nano-silica carrier and polybetaine conditioning, resulted in an increased release of cerium ions and enzyme mimetic activity, without tangible loss of mechanical properties. Ex vivo experiments confirmed these observations. In stressed human gingival fibroblasts, i-PMMA reduced the levels of reactive oxygen species and increased the expression of homeostasis-related proteins (PPARg, ATG5, LCI/III). Furthermore, i-PMMA increased the levels of expression of superoxide dismutase and mitogen-activated protein kinases (ERK and Akt), and cellular migration. Lastly, we demonstrated the biosafety of i-PMMA using two in vivo models: skin sensitization assay and oral mucosa irritation test, respectively. Therefore, i-PMMA offers a cytoprotective interface that prevents microbial adhesion and attenuates oxidative stress, thus supporting physiological recovery of the oral mucosa.


Assuntos
Cério , Polimetil Metacrilato , Humanos , Metacrilatos , Cério/farmacologia , Próteses e Implantes
15.
Pediatr Int ; 65(1): e15472, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36645370

RESUMO

BACKGROUND: The age-adjusted prevalence of child and adolescent obesity has been stabilized in the Korean population, although severe obesity has increased with adverse health effects. In this study, we detailed the prevalence of and trends in overweight, obesity, and severe obesity in Korean children and adolescents by age group and sex from a nationally representative sample, using a new, 2017 age- and sex-specific reference for body mass index. METHODS: We collected Korea National Health and Nutrition Examination Survey data from the years 2007-2020. A total of 23,595 subjects (11,210 females) aged 2-18 years were included in this study. We calculated the recent prevalence of overweight and obesity, including severe obesity, by weighted data from 2019 and 2020. RESULTS: The prevalence of overweight and obesity (class II and class III obesity) was 23.5% and 14.2% (2.5% and 0.5%), respectively. Males showed a higher prevalence of overweight and obesity. Adolescents aged 13-15 years showed the highest prevalence of severe obesity. A positive linear trend was significant for overweight (p = 0.025), class I obesity (p < 0.001), and class II obesity (p = 0.002) for both sexes and all ages combined. However, the trend of obesity prevalence was different in each subgroup. Comparing pre- and post- COVID-19 pandemic, obesity prevalence seemed to increase, but not significantly. CONCLUSIONS: Despite previous reports that obesity in children and adolescents has remained stable, we found that the prevalence of overweight, obesity, and severe obesity has increased in Korean children and adolescents. The effects of COVID-19 on this trend require further evaluation.


Assuntos
COVID-19 , Obesidade Mórbida , Obesidade Infantil , Masculino , Feminino , Criança , Adolescente , Humanos , Obesidade Mórbida/epidemiologia , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Inquéritos Nutricionais , Prevalência , Pandemias , COVID-19/epidemiologia , Índice de Massa Corporal , República da Coreia/epidemiologia
17.
J Mech Behav Biomed Mater ; 138: 105634, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36543086

RESUMO

Poly (methyl methacrylate) (PMMA) is a commonly used material for the fabrication of biomedical appliances. Although PMMA has several advantages, it is susceptible to microbial insults with practical use. Therefore, different bioactive nanomaterials, such as nanoceria (CeN), have been proposed to enhance the properties of PMMA. In this study, we investigated the effect of the incorporation of CeN into PMMA with and without the use of mesoporous silica nanoparticle (SBA-15) carriers. The unmodified PMMA specimens (control, CTRL) were compared to groups containing SBA-15, CeN, and the synthesized SBA-15 impregnated with CeN (SBA-15@CeN) at different loading percentages. The mechanical and physical properties of the different SBA-15@CeN groups and their effects on cell viability were investigated, and the optimal CeN concentration was identified accordingly. Our results revealed that flexural strength was significantly (P < 0.01) reduced in the SBA-15@CeN3× group (containing 3-fold the CeN wt. %). Although the surface microhardness increased with the increase in the wt. % of SBA-15@CeN, cell viability was significantly reduced (P < 0.001). The SBA-15@CeN1× group had the optimal concentration and displayed significant resistance to single-and multispecies microbial colonization. Finally, the enzymatic activity of CeN was significantly high in the SBA-15@CeN1× group. The proinflammatory markers (IL-6, IL-1ß, TNF-α, CD80, and CD86) showed a significant (P < 0.001) multifold reduction in lipopolysaccharide-induced RAW cells treated with a 5-day eluate of the SBA-15@CeN1× group. These results indicate that the addition of SBA-15@CeN at 1.5 wt % improves the biological response of PMMA without compromising its mechanical properties.


Assuntos
Bases de Dentadura , Polimetil Metacrilato , Dióxido de Silício , Propriedades de Superfície , Teste de Materiais
18.
Biomater Sci ; 11(2): 554-566, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36472228

RESUMO

Hybrid ionomer cements (HICs) are aesthetic polyelectrolyte cements that have been modified with a resin. The setting of HICs occurs by both monomer polymerization and an acid-base reaction. In addition, HICs contain a resin, which is substituted for water. Thus, the competition between the setting reactions and reduced water content inherently limits polysalt formation and, consequently the bioactive interactions. In this study, we explored the effects of polybetaine zwitterionic derivatives (mZMs) on the augmentation of the bioactive response of HICs. The polybetaines were homogenized into an HIC in different proportions (α, ß, and γ) at 3% w/v. Following basic characterization, the bioactive response of human dental pulp stem cells (hDPSCs) was evaluated. The augmented release of the principal constituent ions (strontium, silica, and fluoride) from the HIC was observed with the addition of the mZMs. Modification with α-mZM elicited the most favorable bioactive response, namely, increased ion elution, in vitro calcium phosphate precipitation, and excellent biofouling resistance, which deterred the growth of the bridging species of Veillonella. Moreover, α-mZM resulted in a significant increase in the hDPSC response, as confirmed by a significant increase (p < 0.05) in alizarin red staining. The results of mRNA expression tests, performed using periodically refreshed media, showed increased and early peak expression levels for RUNX2, OCN, and OPN in the case of α-mZM. Based on the results of the in vitro experiments, it can be concluded that modification of HICs with polybetaine α-mZM can augment the overall biological response.


Assuntos
Fluoretos , Cimentos de Ionômeros de Vidro , Humanos , Cimentos Ósseos , Teste de Materiais
20.
Sci Rep ; 12(1): 19456, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376540

RESUMO

Colonization of auto-polymerized acrylic resin by pathogenic Candida albicans is a common problem for denture users. In this study, zinc-modified phosphate-based glass was introduced into an auto-polymerized acrylic resin at concentrations of 3, 5, and 7 wt.%. The mechanical or physical properties (flexural strength, elastic modulus, microhardness, and contact angle), surface morphology of the resultant materials, and the antimicrobial effect on C. albicans were investigated. There were no statistical differences in the mechanical properties between the control and the zinc-modified phosphate-based glass samples (p > 0.05); however, the number of C. albicans colony-forming units was significantly lower in the control group (p < 0.05). Scanning electron microscopy revealed that C. albicans tended not to adhere to the zinc-modified-phosphate-based glass samples. Thus, the zinc-modified materials retained the advantageous mechanical properties of unaltered acrylic resins, while simultaneously exhibiting a strong antimicrobial effect in vitro.


Assuntos
Resinas Acrílicas , Anti-Infecciosos , Resinas Acrílicas/farmacologia , Candida albicans , Bases de Dentadura , Propriedades de Superfície , Teste de Materiais , Fosfatos/farmacologia , Zinco/farmacologia
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