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1.
J Environ Sci (China) ; 148: 274-282, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095164

RESUMEN

Developing cost-effective and high-performance catalyst systems for dry reforming of methane (DRM) is crucial for producing hydrogen (H2) sustainably. Herein, we investigate using iron (Fe) as a promoter and major alumina support in Ni-based catalysts to improve their DRM performance. The addition of iron as a promotor was found to add reducible iron species along with reducible NiO species, enhance the basicity and induce the deposition of oxidizable carbon. By incorporating 1 wt.% Fe into a 5Ni/10ZrAl catalyst, a higher CO2 interaction and formation of reducible "NiO-species having strong interaction with support" was observed, which led to an ∼80% H2 yield in 420 min of Time on Stream (TOS). Further increasing the Fe content to 2wt% led to the formation of additional reducible iron oxide species and a noticeable rise in H2 yield up to 84%. Despite the severe weight loss on Fe-promoted catalysts, high H2 yield was maintained due to the proper balance between the rate of CH4 decomposition and the rate of carbon deposit diffusion. Finally, incorporating 3 wt.% Fe into the 5Ni/10ZrAl catalyst resulted in the highest CO2 interaction, wide presence of reducible NiO-species, minimum graphitic deposit and an 87% H2 yield. Our findings suggest that iron-promoted zirconia-alumina-supported Ni catalysts can be a cheap and excellent catalytic system for H2 production via DRM.


Asunto(s)
Óxido de Aluminio , Hidrógeno , Hierro , Metano , Níquel , Circonio , Metano/química , Circonio/química , Catálisis , Hierro/química , Hidrógeno/química , Óxido de Aluminio/química , Níquel/química
2.
Protein Expr Purif ; 225: 106595, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39197671

RESUMEN

We previously reported a chromatography system for purifying immunoglobulin M (IgM) using N,N,N',N'-ethylenediaminetetrakis(methylenephosphonic acid)-modified zirconia particles that selectively absorb immunoglobulins. Here, we report a simple procedure for preparing biotinylated IgM from hybridoma culture medium using this zirconia-based chromatography system. The culture medium of an IgM-producing hybridoma cell line was used as the starting sample solution, and the IgM in the medium was concentrated and partially purified by zirconia chromatography. Next, 9-(biotinamido)-4,7-dioxanonanoic acid N-succinimidyl ester was added to react with the proteins in the sample. Subsequently, only the biotinylated IgM was isolated by Capto Core 400 polishing column chromatography. The entire process was easy to perform, could be completed within 2 h, and provided highly pure biotin-labeled IgM. This procedure is expected to be applicable to the labeling of IgM with various compounds and drugs.


Asunto(s)
Biotinilación , Medios de Cultivo , Hibridomas , Inmunoglobulina M , Inmunoglobulina M/química , Inmunoglobulina M/aislamiento & purificación , Animales , Medios de Cultivo/química , Ratones , Circonio/química , Biotina/química
3.
Braz Oral Res ; 38: e077, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39258630

RESUMEN

Borosilicate glass was developed to enhance the mechanical behavior and smoothness of dental zirconia as an alternative to conventional glaze. This study assessed the mechanical and optical properties of 3 mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP) coated with borosilicate glass or a commercial glaze fired for an extended period of time. Disc-shaped 3Y-TZP zirconia specimens (Zpex, Tosoh) were sintered at 1550°C for 2 hours. The specimens were divided into three groups: as-sintered (control, C); commercial glaze (G); and borosilicate glass (SL). The glaze and borosilicate glass were applied over the zirconia and fired for 20 minutes at 950°C and 1200°C, respectively. Biaxial flexural strength, fractography, X-ray diffraction (XRD), roughness (Ra and Rz), fracture toughness (Vickers indentation method), color difference (∆E00), and translucency (TP00) analyses were conducted. The t-test or the one-way ANOVA and Tukey's tests were used to analyze the data (α = 0.05). Flexural strength data were subjected to the Weibull analysis. The SL group exhibited the highest flexural strength (1025.8 MPa), whereas the C (859.41 MPa) and G (816.0 MPa) groups exhibited similar values. The SL group also had the highest characteristic strength. The fracture origin in all groups was on the zirconia surface. XRD analysis revealed that the specimens from the SL group contained tetragonal, cubic, and monoclinic phases. The SL group presented the lowest surface roughness. Fracture toughness in the SL group was lower than in the C group, but similar to that observed in the G group. The translucency and color differences observed in the G and SL groups were similar. Borosilicate glass enhanced the flexural strength of 3Y-TZP, promoted the smoothest surface, and exhibited optical properties similar to those of the glaze.


Asunto(s)
Vidrio , Ensayo de Materiales , Propiedades de Superficie , Difracción de Rayos X , Itrio , Circonio , Circonio/química , Itrio/química , Vidrio/química , Análisis de Varianza , Factores de Tiempo , Resistencia Flexional , Silicatos/química , Reproducibilidad de los Resultados , Valores de Referencia , Estadísticas no Paramétricas , Color , Fenómenos Ópticos , Pruebas de Dureza , Materiales Dentales/química
4.
Am J Dent ; 37(5): 263-267, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39321107

RESUMEN

PURPOSE: To evaluate the marginal and internal misfit of fixed partial denture zirconia frameworks developed from conventional impression and intraoral scanning, before and after being subjected to the thermal cycle of the covering ceramic. METHODS: A three-elements fixed partial denture was prepared, molded, and poured with polyurethane. Group CI (n= 7) was impressed by the conventional technique with polyvinyl siloxane material, and the plaster models scanned on the inEosX5 bench scanner. Group DI (n=07) was scanned using the CEREC Bluecam intraoral scanner. The models and images obtained were sent to the laboratory and the frameworks were made using zirconia blocks. After this, they were subjected to the ceramic thermal cycle, simulating the ceramic application. Marginal and internal misfits of the frameworks were measured before (T1) and after (T2) thermal cycle simulation using the replica technique in an optical microscope. Statistical analysis was performed using the mixed effects of linear model tests and comparisons. RESULTS: There were no statistical differences for axial misfit. Significant differences were found between the groups for occlusal, vertical, horizontal, and absolute misfit, where group CI had higher values than group DI (P< 0.001). At the time, there was a statistical difference only in the absolute misfit, where T1 had lower values than T2. The misfit in group CI was greater than in group DI; however, the average misfit values found are low and considered clinically acceptable. CLINICAL SIGNIFICANCE: Knowing marginal and internal misfit is an important step to consolidating digital impressions in fixed partial dentures, implying a secure use of this technique.


Asunto(s)
Diseño Asistido por Computadora , Técnica de Impresión Dental , Adaptación Marginal Dental , Diseño de Dentadura , Dentadura Parcial Fija , Circonio , Circonio/química , Diseño de Dentadura/métodos , Humanos , Siloxanos/química , Materiales de Impresión Dental/química , Polivinilos/química , Modelos Dentales
5.
Braz Dent J ; 35: e245917, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39320003

RESUMEN

To evaluate the fracture load of bilayer ceramic crowns manufactured by Rapid Layer Technology (RLT) after different cementation protocols of the veneering ceramic to the zirconia infrastructures. Sixty epoxy resin preparations simulating a molar tooth were obtained and 60 zirconia infrastructures and feldspathic crowns were manufactured by RLT and divided into 6 groups according to the cementation protocol at the interface to veneering ceramic (n=10): Ctr- control: conventional resin cement; Al- Al2O3 sandblasting 50µm + conventional resin cement; Al/MDP- Al2O3 sandblasting (50µm) + resin cement with MDP; Sil- silicatization 30µm + conventional resin cement; Gl/HF- glaze + hydrofluoridric acid (5%,60s) + silane + conventional resin cement; Gl- glazing as bonding agent. The feldspathic ceramic internal surface was etched with fluoridric acid (5%) + silane followed by cementation according to respective protocols. All samples were mechanically cycled (200N and 4.5x105 Pa, 37°C, 2x106 cycles, 3.4Hz) and submitted to axial compressing fracture load test (10kN, 0.5mm/min). The results(N) were submitted to descriptive and analytical statistical analysis with 1-way ANOVA, Weibull, and the Tukey test (α=0.05). ANOVA revealed that there was a significant difference among the tested groups (p<0.0001). The group Al/MDP presented the higher resistance to fracture (1972.46A N), followed by the Ctr group (1584.41B N). The characteristic strength(σ0) was significantly different (p=0.000). The crack and chipping were the predominant failures. The air-abrasion at the external surface of zirconia with Al2O3 followed by cementation with MDP resin cement, should be selected to Rapid Layer Technique when felspathic ceramic is used as veneer ceramic.


Asunto(s)
Cementación , Cerámica , Coronas , Análisis del Estrés Dental , Ensayo de Materiales , Cerámica/química , Cementación/métodos , Circonio/química , Fracaso de la Restauración Dental , Cementos Dentales/química
6.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 42(5): 652-659, 2024 Oct 01.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-39304509

RESUMEN

OBJECTIVES: This study aimed to estimate the therapeutic effects of preformed metal crown (PMC) and prefabricated zirconia crowns (ZC) on decayed primary morals in children, as well as to analyze the possible influencing factors. METHODS: A retrospective cohort study was performed on the data of 192 patients (aged 3 to 8) in the Stomatological Department of Shenzhen Children's Hospital from October 2021 to December 2021. The decayed mandibular first molars were selected and restored by vital-pulp therapy followed by PMC and ZC, including 96 cases (96 caries) in the PMC group and 96 cases (96 caries) in the ZC group. Oral clinical examination was performed at 3 months, 1 year, and 2 years after treatment, overwiewing the clinical therapeutic effects and periodontal status of PMC and ZC groups, as well as recording the crown integrity, gingival index (GI), probing bleeding index (BI), plaque index (PLI) and various prosthetic indices. RESULTS: No significance differences existed in the periodontal status of PMC and ZC groups at 3 months, 1 year, and 2 years after treatment (P>0.05). However, the GI, BI, and PLI in the PMC group were higher than those in the ZC group at 3 months, 1 year, and 2 years after treatment, and the difference was dramatically significant (P<0.05). No significances difference existed in various prosthetic indices (P>0.05), as well as in the GI, BI, and PLI, between the two groups (P>0.05). No significant differences existed in various prosthetic indices between genders after PMC restoration (P>0.05). The scores of girls in various prosthetic indices after ZC restoration were higher than those of boys (P<0.05). Pearson correlation analysis indicated an inverse correlation between age in the PMC group and the GI, BI, PLI, and FDI indices (P<0.01), rather than in the ZC group (P>0.05). CONCLUSIONS: PMC and ZC can be applied to restore deciduous molar caries. The periodontal status of deciduous teeth in ZC group was superior to that in the PMC group. The periodontal status of deciduous teeth in PMC group may be stable with increased age.


Asunto(s)
Coronas , Caries Dental , Diente Molar , Diente Primario , Circonio , Humanos , Estudios Retrospectivos , Niño , Preescolar , Femenino , Masculino , Índice Periodontal
7.
Int J Prosthodont ; 37(5): 211-222, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39331577

RESUMEN

PURPOSE: To evaluate the influence of abutment material, cement thickness, and crown type on the esthetics of implant supported restorations. MATERIAL AND METHODS: In total, 60 specimens were prepared to represent six abutment groups: Group PA = pink-anodized Ti; Group GA = gold-anodized Ti; Group T = nonanodized Ti; Group H = hybrid (Ti + zirconia); Group P = PEEK (Ti + PEEK); and Group C = composite resin (control). Crown specimens (n = 120) were obtained from Vita Enamic (VE) and Vita Suprinity (VS). Two cement thicknesses (0.1 and 0.2 mm) were used. The color values of crown configura:ons were measured and ΔE00* values were calculated. Statistical analyses included were Shapiro Wilk, three-way ANOVA, and Tukey HSD tests (P ≤ .05). RESULTS: Abutment (P < .001) and crown materials (P = .001) had a significant effect on ΔE00* values, while cement thickness did not. Groups PA and H resulted in significantly lower mean ΔE00* values than other abutments, whereas Group T revealed the highest. Unlike VS, cement thicknesses created a significant difference on the ΔE00* values for VE (P ≤.05). CONCLUSIONS: Pink-anodized Ti or hybrid abutments for VE and pink- or goldanodized Ti for VS seem to be better options, in terms of color change. Cement thickness of 0.1 mm resulted in higher ΔE00* value than 0.2 mm for VE (P ≤ .05).


Asunto(s)
Color , Coronas , Pilares Dentales , Cementos Dentales , Prótesis Dental de Soporte Implantado , Cementos Dentales/química , Estética Dental , Humanos , Circonio/química , Diseño de Implante Dental-Pilar , Resinas Compuestas/química , Materiales Dentales/química , Coloración de Prótesis , Diseño de Prótesis Dental , Ensayo de Materiales
8.
Int J Prosthodont ; 37(5): 547-558, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39331580

RESUMEN

PURPOSE: To compare the color dimensions, color discrepancies (ΔE00), and surface roughness of milled materials before and after application of a bleaching agent. MATERIALS AND METHODS: A total of 10 extracted molars were obtained. Each tooth was cut in transverse sections to create disks (3-mm thick, 10-mm diameter; control group). Disk specimens of eight materials (n = 10 per group) were fabricated: polymethyl methacrylate (PMMA) interim material (PMMA-Telio group), two resin nanoceramics (RNC-Ultimate group and RNC-Cerasmart group), two hybrid ceramics (HC-Shofu group and HC-Enamic group), lithium disilicate (LD-Emax group), zirconia-reinforced glass ceramic (ZGC-Suprinity group), and zirconia (Zr-InCeram group). Color measurements were obtained using a spectrophotometer before and after applying 35% hydrogen peroxide-based bleaching agent. Pre- and postbleaching surface roughness (Sa) analyses were completed using a profilometer. RESULTS: Significant L*, a*, b*, and ΔE00 value differences were found (P < .05). Color discrepancies (ΔE00) ranged from 0.30 ± 0.14 to 4.82 ± 0.10. The highest color discrepancies were measured on the PMMA-Telio group, while the lowest color discrepancies were computed for ZGC-Suprinity, RNCUltimate, and RNC-Cerasmart. Significant surface roughness differences were found (P < .05). The largest increase of surface roughness values between the pre- and postbleaching measurements was obtained in the PMMA-Telio group with a mean ΔSa value of 4.73 ± 3.02, while the largest decrease of surface roughness values between the pre- and postbleaching measurements was obtained in the Zr-InCeram group with a mean ΔSa value of -1.58 ± 0.10. CONCLUSIONS: The milled materials showed significant pre- and postbleaching color and surface roughness discrepancies.


Asunto(s)
Cerámica , Color , Materiales Dentales , Peróxido de Hidrógeno , Propiedades de Superficie , Circonio , Materiales Dentales/química , Cerámica/química , Circonio/química , Humanos , Porcelana Dental/química , Ensayo de Materiales , Blanqueadores Dentales/química , Espectrofotometría , Polimetil Metacrilato/química , Restauración Dental Permanente
9.
Biomed Res Int ; 2024: 5394652, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39220997

RESUMEN

Background: Adhesion to zirconia remains a significant dental challenge. This study is aimed at assessing the bond strength of zirconia based on surface treatment with pre or postsintering sandblasting associated with different chemical treatments and resin cements. Methods: Zirconia blocks were divided into 12 experimental groups based on the surface treatment (presintering sandblasting or postsintering sandblasting/tribochemical abrasion treatment), chemical treatment (none, Single Bond Universal, or Signum Zirconia Bond), and choice of cement (Panavia F or RelyX™ U200). The bond strength was measured by shear tests using a universal testing machine. The fracture analysis was performed using stereomicroscopy. Data were analyzed using three-way ANOVA and Tukey's test (α = 5%). Results: Triple and double factor's interactions were not significant (p > 0.05). Regarding the surface treatment factor, the bond strength following postsintering sandblasting treatment associated with tribochemical abrasion (9.15 ± 3.62 MPa) was significantly higher than presintering sandblasting treatment (5.24 ± 3.53 MPa). Concerning the chemical treatment factor, bond strengths were ranked as follows: Signum Zirconia Bond > Single Bond Universal > no treatment. The bond strength of the resin cements did not differ among them. Most fractures (67%) were classified as adhesive, and 32% were categorized as mixed fractures. Conclusion: Surface treatment via postsintering sandblasting combined with tribochemical abrasion demonstrated superior efficacy than in presintering sandblasting. Additionally, chemical treatment with zirconia primer increased the bond strength of zirconia irrespective of the surface physical treatment.


Asunto(s)
Recubrimiento Dental Adhesivo , Ensayo de Materiales , Cementos de Resina , Propiedades de Superficie , Circonio , Circonio/química , Cementos de Resina/química , Recubrimiento Dental Adhesivo/métodos , Resistencia al Corte , Cementos Dentales/química , Humanos
10.
Acta Medica (Hradec Kralove) ; 67(1): 26-31, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39288443

RESUMEN

Recent advancements in digital technologies have transformed clinical workflows in dentistry, ensuring precise restorations. Custom-made crowns and fixed partial dentures (FPDs) now rely on virtual articulation. The digital facebow provides individualized data for CAD settings, streamlining the fabrication via digital workflow. For the purpose of demonstrating the differences observed during fabrication, we present a case report involving a 68-year-old patient seeking a replacement for missing teeth 24, 25, 26, and 27. The treatment plan involved the fabrication of an implant-supported FPD using monolithic zirconia (ZrO2). However, technical hurdles emerged during the planning phase, primarily due to spatial limitations posing a risk of mechanical failure over time. Consequently, we pivoted approach towards a porcelain fused to metal (PFM) FPD. For the PFM FPD, individual values from the digital facebow adjusted both virtual and conventional articulators. For comparison, two ZrO2 FPDs were milled-individual settings and average settings. All restorations underwent assessment for occlusion in maximal intercuspal position and eccentric mandible movements. In conclusion, the case report showed that individualized PFM FPD required minimal adjustments compared to milled ZrO2 restorations, whether using individual or average values. Utilizing individual values from the digital facebow reduced operator working time and minimized the intraoral adjustments.


Asunto(s)
Diseño Asistido por Computadora , Coronas , Prótesis Dental de Soporte Implantado , Humanos , Anciano , Prótesis Dental de Soporte Implantado/métodos , Flujo de Trabajo , Circonio , Dentadura Parcial Fija , Diseño de Prótesis Dental/métodos , Masculino
11.
BMC Oral Health ; 24(1): 1073, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39261788

RESUMEN

BACKGROUND: Advancements in digital dentistry helped in custom-milling screw-channels in implant-supported restorations; however, the fit of these restorations is still unclear especially for contemporary computer aided designing/computer aided manufacturing (CAD/CAM) materials. This study aimed to compare the internal and marginal fit of Ultra translucent multilayered zirconia versus lithium disilicate implant-supported hybrid abutment crowns (HACs) constructed with custom-milled screw-channels on Titanium-base. MATERIALS AND METHODS: A total of 24 HACs with custom-milled screw-channels were constructed from lithium disilicate (Group LDS) and Ultra translucent multilayered zirconia (Group UT) using digital workflow (n = 12). The internal and marginal gaps of HACs on their corresponding Titanium-bases were assessed using replica technique and stereomicroscope, respectively. After testing for normality, quantitative data were expressed as mean and standard deviation and compared using independent t-test at a level of significance (P ≤ 0.05). RESULTS: There was no statistically significant difference between Group LDS and Group UT in terms of marginal and internal fit. The internal and marginal gaps in both groups were within the accepted values reported in literature. CONCLUSIONS: UT and LDS HACs with custom-milled screw-channels demonstrated comparable and acceptable internal fit and marginal adaptations to Ti-base, which lied within the range reported in literature.


Asunto(s)
Diseño Asistido por Computadora , Coronas , Diseño de Implante Dental-Pilar , Adaptación Marginal Dental , Prótesis Dental de Soporte Implantado , Titanio , Circonio , Titanio/química , Circonio/química , Humanos , Porcelana Dental/química , Técnicas In Vitro , Pilares Dentales , Cerámica/química , Diseño de Prótesis Dental
12.
BMC Oral Health ; 24(1): 1065, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39261857

RESUMEN

BACKGROUND: Recently, prosthodontic approaches involve more conservative procedures that include less invasive finish line preparations that use less ceramic thickness. AIM OF THE STUDY: This in vitro study aimed to evaluate the effect of vertical preparation and modified vertical preparation designs on the marginal adaptation and fracture resistance of two types of ceramic crowns using CAD/CAM technology. MATERIALS AND METHODS: Two typodont maxillary first premolars were embedded in acrylic resin. Forty positive replicas of epoxy resin dies were used that were divided into two groups depending on the preparation design (n = 20); Group V (Vertical): dies with feather edge finish line and Group MV (Modified vertical): dies with feather edge finish line, where a reverse shoulder of 1 mm depth was placed on the buccal surface 1.5 mm from the occlusal surface. Each group was further subdivided into two subgroups according to the type of ceramic material (n = 10): Subgroup Va and subgroup MVa for lithium disilicate (e.max CAD) and subgroup Vb and subgroup MVb for zirconia (zolid ht+). Crown restorations were made with CAD-CAM technology. The marginal adaptation was assessed using a stereomicroscope both prior to cementation and after cementation and aging. Fracture resistance was tested with a universal testing machine, and the data were statistically analyzed. RESULTS: Marginal adaptation showed no significant differences between subgroups before or after cementation and aging. Three-way ANOVA indicated that preparation design (p = 0.516) and material (p = 0.269) had no significant effect, but cementation had a significant effect (p < 0.0001) on the marginal adaptation. According to two-way ANOVA test, Subgroup (MVb) showed the highest result followed by subgroup (Vb) and subgroub (MVa) and the least was subgroub (Va). Fracture modes showed no significant differences among the subgroups (p = 0.982). CONCLUSIONS: Marginal adaptation of lithium disilicate and zirconia crowns remained clinically acceptable regardless of preparation design. While the modified vertical preparation with a reverse shoulder notably enhanced the fracture resistance of both materials, with zirconia demonstrating superior fracture resistance compared to lithium disilicate with average values exceeding premolar biting force.


Asunto(s)
Cerámica , Diseño Asistido por Computadora , Coronas , Adaptación Marginal Dental , Porcelana Dental , Diseño de Prótesis Dental , Análisis del Estrés Dental , Circonio , Circonio/química , Porcelana Dental/química , Humanos , Técnicas In Vitro , Cerámica/química , Fracaso de la Restauración Dental , Ensayo de Materiales , Diente Premolar
13.
Nano Lett ; 24(37): 11738-11746, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39229926

RESUMEN

Fluoride-based lanthanide-doped nanoparticles (LDNPs) featuring second near-infrared (NIR-II, 1000-1700 nm) downconversion emission for bioimaging have attracted extensive attention. However, conventional LDNPs cannot be degraded and eliminated from organisms because of an inert lattice, which obstructs bioimaging applications. Herein, the core-shell LDNPs of Na3HfF7:Yb,Er@CaF2:Ce,Zr(Hf) [labeled as Zr(Hf)Ce-HC] with pH-selective and tunable degradability were synthesized for dual-modal bioimaging. Notably, the "softening" lattice of the Na3HfF7 matrix and different Zr4+(Hf4+) doping amounts in the shell enable Zr(Hf)Ce-HC with acidity-dependent and tunable degradability. After coating of an optimized Ce3+-doped CaF2:Zr shell, the near-infrared-IIb (NIR-IIb, 1500-1700 nm) luminescence intensity of ZrCe-HC is enhanced by 5.2 times compared with that of Na3HfF7:Yb,Er. The Hf element with high X-ray attenuation allows ZrCe-HC as the contrast agent for computed tomography (CT) bioimaging. The modification of oxidized sodium alginate endows ZrCe-HC with satisfying biocompatibility for NIR-IIb/CT dual-modal bioimaging. These findings would benefit the bioimaging applications of degradable fluoride-based LDNPs.


Asunto(s)
Fluoruros , Hafnio , Circonio , Circonio/química , Humanos , Hafnio/química , Fluoruros/química , Nanopartículas/química , Tomografía Computarizada por Rayos X/métodos , Animales , Medios de Contraste/química
14.
BMC Oral Health ; 24(1): 1033, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39227885

RESUMEN

BACKGROUND: The accuracy of intraoral scanning is critical for computer-aided design/computer-aided manufacturing workflows in dentistry. However, data regarding the scanning accuracy of various adjacent restorative materials and intraoral scanners are lacking. This in vitro study aimed to evaluate the effect of adjacent restorative material type and CEREC's intraoral scanners on the accuracy of intraoral digital impressions for inlay cavities. METHODS: The artificial tooth was prepared with an occlusal cavity depth of 2 mm, a proximal box width at the gingival floor of 1.5 mm, and an equi-gingival margin extended disto-occlusally at the transition line angle on both the lingual and buccal sides for an inlay restoration. The adjacent teeth were veneered with crowns made of gold and zirconia, and an artificial tooth (resin) was utilized as the control group. The inlay cavity and adjacent teeth (Gold, Zirconia, and resin) were scanned 10 times using Chairside Economical Restoration of Esthetic Ceramics (CEREC) Primescan (PS), Omnicam (OC), and Bluecam (BC). A reference scan was obtained using a laboratory scanner (3-shape E3). Scanning was performed according to the manufacturer's instructions, including powder application for the BC group. Standard tesselation language files were analyzed using a three-dimensional analysis software program. Experimental data were analyzed using a two-way analysis of variance and the Tukey's post-hoc comparison test. RESULTS: The restorative materials of the adjacent teeth significantly affected the accuracy of the intraoral digital impressions (p < .05). The zirconia group exhibited the highest trueness deviation, followed by the resin and gold groups, with each demonstrating a statistically significant difference (p < .05). The resin group demonstrated the highest maximum positive deviation and deviation in precision. Gold exhibited the lowest average deviation value for trueness compared with those of the other adjacent restorative materials. Intraoral scanner type significantly influenced the trueness and precision of the scan data (p < .05). The average deviation of trueness according to the intraoral scanner type increased in the following order: BC > PS > OC. The average deviation in precision increased in the following order: PS>OC>BC (p < .05). CONCLUSION: The restorative materials of the adjacent tooth and the type of intraoral scanner affect the accuracy of the intraoral digital impression. The trueness of the digital images of the BC group, obtained by spraying the powder, was comparable to that of the PS group. Among the adjacent restorative materials, zirconia exhibited the lowest trueness. In contrast, PS demonstrated the highest precision among the intraoral scanners, while resin displayed the lowest precision among the adjacent restorative materials.


Asunto(s)
Diseño Asistido por Computadora , Incrustaciones , Circonio , Humanos , Técnica de Impresión Dental , Técnicas In Vitro , Materiales Dentales , Coronas , Cerámica , Diseño de Prótesis Dental/métodos , Restauración Dental Permanente/métodos
15.
Theranostics ; 14(12): 4582-4597, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39239511

RESUMEN

Increasing evidence emphasizes the pivotal role of CD4+ T cells in orchestrating cancer immunity. Noninvasive in vivo imaging of the temporal dynamics of CD4+ T cells and their distribution patterns might provide novel insights into their effector and regulator cell functions during cancer immunotherapy (CIT). Methods: We conducted a comparative analysis of 89Zr-labeled anti-mouse (m) and anti-human (h) CD4-targeting minibodies (Mbs) for in vivo positron emission tomography (PET)/magnetic resonance imaging (MRI) of CD4+ T cells in human xenografts, syngeneic tumor-bearing wild-type (WT), and human CD4+ knock-in (hCD4-KI) mouse models. Results: Both 89Zr-CD4-Mbs yielded high radiolabeling efficiencies of >90%, immunoreactivities of >70%, and specific in vitro binding to their target antigens. The specificity of in vivo targeting of 89Zr-hCD4-Mb was confirmed by PET/MRI, revealing ~4-fold greater 89Zr-hCD4-Mb uptake in subcutaneous hCD4+ hematopoietic peripheral blood acute lymphoblastic leukemia tumors (HPB-ALL) than in solid hCD4- diffuse histiocytic lymphomas (DHL) and 89Zr-mCD4-Mb uptake in hCD4+ HPB-ALL tumors. In a comparative cross-validation study in anti-programmed death ligand (αPD-L1)/anti-4-1BB-treated orthotopic PyMT mammary carcinoma-bearing hCD4-KI and WT mice, we detected 2- to 3-fold enhanced species-specific 89Zr-hCD4-Mb or 89Zr-mCD4-Mb uptake within CD4+ cell-enriched secondary lymphatic organs (lymph nodes and spleens). The 89Zr-hCD4-Mb uptake in the PyMT tumors was more pronounced in hCD4-KI mice compared to the WT control littermates. Most importantly, MC38 adenocarcinoma-bearing mice treated with a combination of αPD-L1 and anti-lymphocyte-activation gene 3 (αLag-3) antibodies exhibited ~1.4-fold higher 89Zr-mCD4-Mb uptake than mice that were not responsive to therapy or sham-treated mice. Conclusion: CD4 PET/MRI enabled monitoring of the CD4+ cell distribution in secondary lymphatic organs and the tumor microenvironment, capable of predicting sensitivity to CIT. Our imaging approach will provide deeper insights into the underlying molecular mechanisms of CD4-directed cancer immunotherapies in preclinical mouse models and is applicable for clinical translation.


Asunto(s)
Linfocitos T CD4-Positivos , Inmunoterapia , Tomografía de Emisión de Positrones , Circonio , Animales , Humanos , Ratones , Tomografía de Emisión de Positrones/métodos , Inmunoterapia/métodos , Linfocitos T CD4-Positivos/inmunología , Imagen por Resonancia Magnética/métodos , Radioisótopos , Neoplasias/diagnóstico por imagen , Neoplasias/terapia , Neoplasias/inmunología , Línea Celular Tumoral , Femenino
16.
Bioelectrochemistry ; 160: 108801, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39226732

RESUMEN

Flexible technology in sensors have received much attention in monitoring of human health through various physiological indicators. Thus, it drawn a lot of interest in the development of flexible substrate for the diagnosis of various diseases via analysis of analytes. Present work focusses on the development of ecofriendly, portable, flexible, conducting thread (Th) and used as smart substrate for fabrication of biosensor towards ultrasensitive detection of the lung cancer biomarker (cytoskeleton-associated protein 4; CKAP4). The zirconium trisulfide-reduced graphene oxide nanocomposite and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) modified cotton thread based biosensor was fabricated via dip coating method. Next, successive immobilization of monoclonal antibodies of CKAP4 (anti-CKAP4) and bovine serum albumin (BSA) was performed via drop cast approach using fabricated electrode [nZrS3@rGO/PEDOT:PSS/Th]. The response of fabricated electrode (BSA/anti-CKAP4/ZrS3@rGO/PEDOT:PSS/Th) was recorded electrochemically versus CKAP4 concentration via chronoamperometry (CA). The results showed wider linear detection range of 6.25-800 pg mL-1, excellent sensitivity of 85.2 µA[log(pg mL-1)]-1cm-2 with good stability up to 42 days. The response of fabricated biosensor was supported by investigating response of CKAP4 biomarker present in patients of lung cancer (concentration as determined through enzyme-linked immunosorbent assay) and obtained results exhibited excellent correlation with that of standard samples.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Grafito , Neoplasias Pulmonares , Circonio , Grafito/química , Técnicas Biosensibles/métodos , Circonio/química , Humanos , Neoplasias Pulmonares/diagnóstico , Técnicas Electroquímicas/métodos , Límite de Detección , Sulfuros/química , Biomarcadores de Tumor/análisis , Oxidación-Reducción , Electrodos , Albúmina Sérica Bovina/química
17.
Med Sci Monit ; 30: e945130, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39252410

RESUMEN

BACKGROUND This 3-dimensional (3D) optical study aimed to evaluate the effects of microwave glazing on the surface roughness of zirconia-reinforced glass. Glazed surfaces of ceramic provide a smooth and esthetically superior restoration. There are many methods of glazing. However, this study aims to evaluate the effect of microwave glazing on ceramic restorations over conventional oven and hand polishing. MATERIAL AND METHODS A sample size of 90 ceramic material tiles was derived according to the standard sample size formula. The 3 dental ceramics used were IPS e.max CAD (lithium disilicate ceramic; IvoclarVivadent), Suprinity (zirconia-reinforced lithium silicate; VITA Zahnfabrik), and Celtra Duo zirconia-reinforced lithium silicate; Dentsply Sirona). Each group was further divided equally to undergo conventional oven glazing, hand polishing, and microwave glazing. The final glazed surfaces were then evaluated for surface roughness with the Ra parameter, using a Contour GT 3D Optical Microscope (Bruker) and 3D non-contact surface metrology with interferometry. RESULTS The ANOVA test for intergroup comparison showed microwave glazing was a significantly better glazing method than conventional oven and hand polishing (P<0.05). A statistically significant difference was shown between conventional and microwave glazing; however, the difference was greater between conventionally glazed and hand-polished specimens. Furthermore, a highly significant difference between microwave-glazed and hand-polished specimens was observed. CONCLUSIONS Results showed that irrespective of the ceramic, microwave-glazed ceramics were better than traditional oven-glazed ceramics, and hand-polishing resulted in a rougher surface than glazing. Irrespective of the surface treatment methods, IPS e.max CAD ceramic showed a relatively smoother surface than did Suprinity and Celtra Duo.


Asunto(s)
Cerámica , Porcelana Dental , Microondas , Propiedades de Superficie , Circonio , Circonio/química , Cerámica/química , Porcelana Dental/química , Ensayo de Materiales/métodos , Humanos , Materiales Dentales/química , Vidrio/química
18.
BMC Oral Health ; 24(1): 1078, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39272065

RESUMEN

BACKGROUND: Partial coverage concepts have met the main goal of conservative dentistry. Vonlays, which combine features of veneers and onlays, are a recent alternative to full coverage designs and overlay partial coverage restorations. This in vitro study was conducted to compare the fracture resistance of the newly introduced pressable zirconia-reinforced lithium silicate with pressable lithium disilicate ceramic and to determine the optimal preparation design for partial coverage on upper premolars. METHODS: Fifty-two duplicated epoxy resin dies were prepared following vonlay and overlay preparation guidelines. For each preparation (n = 26), the specimens were divided into two subgroups to be restored with lithium disilicate (IPS e.max Press) or zirconia-reinforced lithium silicate (Vita Ambria) (n = 13 each). Ceramic vonlays and overlays were bonded using dual cure resin cement, subjected to thermomechanical fatigue, and the load to fracture was tested by using a universal testing machine. The specimens were fractographically analyzed via scanning electron microscopy (SEM). The normality of the fracture resistance data was checked using the Shapiro‒Wilk test and Q‒Q plots, and two-way ANOVA was used to assess the effect of the type of preparation and ceramic material on the fracture resistance. RESULTS: The group of overlays restored with zirconia-reinforced lithium silicate showed the highest mean fracture load (1218.69 N), while the group of vonlays restored with lithium disilicate had the lowest mean fracture resistance (967.15 N). The effect of preparation design and material type on fracture resistance was significant for both factors, p = 0.003 and p < 0.0001, respectively. Different features of the fracture surfaces, such as arrest lines, hackles, and directions of crack propagation, were observed. CONCLUSIONS: Zirconia-reinforced lithium silicate exhibited greater resistance to fracture compared to lithium disilicate, making it a potential substitute for partial coverage restorations. Additionally, the overlay showed superior fracture resistance when compared to the vonlay preparation design.


Asunto(s)
Diente Premolar , Cerámica , Porcelana Dental , Análisis del Estrés Dental , Ensayo de Materiales , Circonio , Cerámica/química , Porcelana Dental/química , Circonio/química , Humanos , Técnicas In Vitro , Fracaso de la Restauración Dental , Microscopía Electrónica de Rastreo , Maxilar , Diseño de Prótesis Dental , Incrustaciones , Coronas con Frente Estético
19.
Sensors (Basel) ; 24(17)2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39275594

RESUMEN

Monolithic zirconia (MZ) crowns are widely utilized in dental restorations, particularly for substantial tooth structure loss. Inspection, tactile, and radiographic examinations can be time-consuming and error-prone, which may delay diagnosis. Consequently, an objective, automatic, and reliable process is required for identifying dental crown defects. This study aimed to explore the potential of transforming acoustic emission (AE) signals to continuous wavelet transform (CWT), combined with Conventional Neural Network (CNN) to assist in crack detection. A new CNN image segmentation model, based on multi-class semantic segmentation using Inception-ResNet-v2, was developed. Real-time detection of AE signals under loads, which induce cracking, provided significant insights into crack formation in MZ crowns. Pencil lead breaking (PLB) was used to simulate crack propagation. The CWT and CNN models were used to automate the crack classification process. The Inception-ResNet-v2 architecture with transfer learning categorized the cracks in MZ crowns into five groups: labial, palatal, incisal, left, and right. After 2000 epochs, with a learning rate of 0.0001, the model achieved an accuracy of 99.4667%, demonstrating that deep learning significantly improved the localization of cracks in MZ crowns. This development can potentially aid dentists in clinical decision-making by facilitating the early detection and prevention of crack failures.


Asunto(s)
Coronas , Aprendizaje Profundo , Circonio , Circonio/química , Humanos , Redes Neurales de la Computación , Acústica , Análisis de Ondículas
20.
Clin Oral Investig ; 28(10): 528, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39278866

RESUMEN

OBJECTIVES: To investigate the supragingival microbiome surrounding dental implants and neighbouring tooth in periodontitis history and periodontally healthy patients. METHODS: Subjects with a history of periodontitis (test) and periodontally healthy subjects (control) received one of two types of dental implants with different surface characteristics: sandblasted acid-etched (SLA) or precision dimension laser-treated (PDL). Periodontal clinical measurements were collected at baseline (V1), 3 months after implant placement (V4), at zirconia crown placement (V6) and 3 months after zirconia crown placement (V8). Supragingival bacterial microbiota was studied using Illumina MiSeq sequencing. RESULTS: Supragingival microbial community on SLA implants in test group significantly differed to control group at V8 (p < 0.05). A longitudinal shift displaying microbial dysbiosis occurred on SLA implants (p < 0.05) and adjacent teeth (p < 0.05) among test patients from V6 to V8. On PDL implants and the adjacent tooth, no significant difference between test and control groups from V6 to V8 (p > 0.05). Co-occurrence network in test group of SLA implants and the adjacent tooth at V8 showed increased disease-associated bacteria and reduced health-associated bacteria. Health-associated bacteria were dominant in control group of SLA implants at V8. CONCLUSION: The surface characteristics and prosthetic components of dental implants may be important risk factors in patients with a history of periodontitis. CLINICAL RELEVANCE: Dysbiosis of supragingival microbiome may predispose dental implants to peri-implant diseases. Thus, a strict supportive periodontal care plan is imperative to prevent early onset of biological complications.


Asunto(s)
Implantes Dentales , Microbiota , Periodontitis , Humanos , Femenino , Implantes Dentales/microbiología , Masculino , Periodontitis/microbiología , Persona de Mediana Edad , Estudios de Seguimiento , Adulto , Propiedades de Superficie , Circonio , Resultado del Tratamiento , Coronas/microbiología , Grabado Ácido Dental , Implantación Dental Endoósea , Índice Periodontal , Diseño de Prótesis Dental
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