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1.
J Clin Med ; 13(15)2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39124755

RESUMEN

Objective: The goal of this systematic review and meta-analysis was to assess whether there were clinically relevant differences in the treatment of edentulous areas comparing zirconia (Zr) and titanium (Ti) dental implants. The null hypothesis is that no differences can be observed in terms of the clinical parameters; the positive hypothesis I is that Zr implants have generally better results compared to Ti implants; and the positive hypothesis II is that Ti implants have a generally superior result than Zr implants. Methods: This review work was registered on the PROSPERO platform, and its development was conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. The electronic search process was conducted on three databases (PubMed/Scopus/Web of Science), including randomized controlled trials (RCTs) from the past 10 years (up to April 2024). Identified articles were analyzed and included/excluded based on pre-defined selection and exclusion criteria. The quality assessment and risk of bias were evaluated using a Cochrane risk-of-bias assessment tool specifically designed for randomized trials (RoB2). A meta-analysis was conducted to correlate different treatment options based on the described outcomes; a random-effects model was used in the analysis of the variables. The analysis of heterogeneity was conducted by means of Cochran's Q-test and Higgins' I2 statistic. Results: Six RCTs were enrolled; 152 patients (90 males and 62 females) and 448 implants (267 Zr and 181 Ti) were included. Dental implant placement involved both the maxillary and mandibular arches. The implant sites showed heterogeneity in receiving Zr and Ti dental implants; in particular, 22 dental implants were placed in the mid-palatal region and 426 dental implants in the alveolar region (255 were in Zr and 171 in Ti). Regarding the success rate, it was better for Zr but with no statistical difference (p > 0.05); bleeding on probing had slight differences between Ti with 0.34% ± 0.42 and Zr with 0.26% ± 0.36 (p > 0.05); plaque score showed 0.46 ± 0.47 for Ti compared to 0.44 ± 0.49 for Zr (p > 0.05); no statistically significant difference was observed for pink esthetic score (PES). Statistically significant results were found for survival rate, which favored Ti implants (77.6%) compared to Zr (70.3%) (p < 0.05), and for marginal bone loss, which showed less loss in Ti implants (0.18 mm ± 0.47) compared to 0.42 mm ± 0.40 in Zr at 12 months (p < 0.001). Conclusions: The present systematic review and meta-analysis identified the positive hypothesis I and rejected the null and positive hypothesis II; it was possible to conclude that Ti dental implants have a better survival rate and less marginal bone loss than Zr dental implants after 1-year follow-up.

2.
Materials (Basel) ; 16(2)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36676477

RESUMEN

Several composite materials are being investigated as reinforcement fillers for surgery simulations. This study presents an artificial composite material with properties similar to those of the human bone, which may be used in surgery simulations. Moreover, considering the potential toxicity of debris generated during sawing, a safe epoxy-based composite material was synthesized using cellulose nanocrystals (CNCs) and bioceramics (i.e., hydroxyapatite, Yttria stabilized zirconia oxide, Zirconia oxide), which were used to mimic the stiffness of human bone. To examine the change in mechanical properties according to the composition, 1, 3, and 5 wt% of CNCs were mixed with 5 wt% of the bioceramics. When CNCs were added at 1 wt%, there was a confirmed change in the non-linear stiffness and ductility. The CNC-added specimen fractured when forming a nano-network around the local CNCs during curing. In contrast, the specimen without CNCs was more densely structured, and combined to form a network of all specimens such that a plastic region could exist. Thus, this study successfully manufactured a material that could mimic longitudinal and transverse characteristics similar to those of real human bone, as well as exhibit mechanical properties such as strength and stiffness. Bioceramics are harmless to the human body, and can be used by controlling the added quantity of CNCs. We expect that this material will be suitable for use in surgery simulations.

3.
J Pharm Bioallied Sci ; 14(Suppl 1): S968-S970, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36110817

RESUMEN

Objectives: The objective of this study was to compare ZrO2, polyether ether ketone (PEEK), and ZrO2-PEEK telescopic attachments in terms of retention of overdenture. Methodology: Forty-five acrylic resin models of the lower arch were divided into 3 groups of 15 each. In Group I, primary and secondary crowns were constructed from all zirconia (ZrO2), whereas all PEEK was used for Group II and Group III was made up of ZrO2 PEEK. Results: The mean retention value in Group I was 14.12 ± 3.4 N, in Group II was 15.86 ± 5.1, and in Group III was 22.40 ± 10.3 N. The mean final initial retention value in Group I was 14.50 ± 6.1 N, in Group II was 14.97 ± 8.2, and in Group III was 17.21 ± 9.3 N. A significant difference was observed in intergroup comparison (P < 0.05). Conclusion: Zirconia resulted in maximum retention as compared to other telescopic crown materials.

4.
Drug Chem Toxicol ; 42(1): 104-111, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30456988

RESUMEN

Zirconia oxide nanoparticles (ZrO2NPs) are known to be one of the neutral bioceramic metal compounds that has been widely used for their beneficial applications in many biomedical areas, in dental implants, bone joint replacements, drug delivery vehicles, and in various industrial applications. To study the effects of ZrO2NPs on zebrafish model, we used early life stages of the zebrafish (Danio rerio) to examine such effects on embryonic development in this species. ZrO2NPs were synthesized by the sol-gel method, size about 15-20 nm and characterized by SEM, EDX, XRD, FTIR, UV-Vis Spectra. In this study, zebrafish embryos were treated with ZrO2NPs 0.5, 1, 2, 3, 4, or 5 µg of nanoparticles/ml during 24-96 hour post fertilization (hpf). The results showed that ≥0.5-1 µg/ml of ZrO2NPs instigated developmental acute toxicity in these embryos, causing mortality, hatching delay, and malformation. ZrO2NPs exposure induced axis bent, tail bent, spinal cord curvature, yolk-sac, and pericardial edema. A typical phenotype was observed as an unhatched dead embryo at ≥1 µg/ml of ZrO2NPs exposure. This study is one of the first reports on developmental toxicity of zebrafish embryos caused by zirconium oxide nanoparticles in aquatic environments. Our results show that exposure of zirconium oxide nanoparticles is more toxic to embryonic zebrafish at lower concentrations. The results will contribute to the current understanding of the potential biomedical toxicological effects of nanoparticles and support the safety evaluation and synthesis of Zirconia oxide nanoparticles.


Asunto(s)
Embrión no Mamífero/efectos de los fármacos , Desarrollo Embrionario/efectos de los fármacos , Nanopartículas/toxicidad , Pez Cebra/crecimiento & desarrollo , Circonio/toxicidad , Animales , Relación Dosis-Respuesta a Droga , Embrión no Mamífero/anomalías , Embrión no Mamífero/metabolismo , Nanopartículas/química , Nanopartículas/metabolismo , Tamaño de la Partícula , Propiedades de Superficie , Circonio/química , Circonio/metabolismo
5.
J Colloid Interface Sci ; 536: 424-430, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30380442

RESUMEN

Pt nanoparticles immobilized on zirconium oxide (ZrO2) and porous carbons (Pt/ZrO2/PCs) tri-component nanohybrids derived from Pt/ metal-organic frameworks (MOFs) were synthesized. They were prepared by using Pt/MOFs as a template. Additionally, MOFs (UiO-66, a traditional MOFs) were used as ZrO2 and carbon sources without the need of additional precursors. The formation of these composite materials was confirmed through a comprehensive characterization such as transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The Pt/ZrO2/PCs show strong affinity toward the phosphate group and highly electrocatalytic activity for nitro compound on methyl parathion (MP) molecules. The high performance is owing to the combination of unique electrocatalytic activity of Pt species, excellent conductivity of PCs, and good adsorption properties of ZrO2 crystals for MP. The proposed Pt/ZrO2/PCs tri-component nanocomposite sensor realized the ultrasensitive detection of MP with a wide linear range between 3.8 × 10-9 and 1.14 × 10-2 mM and a low limit of detection of 1.45 × 10-9 mM. Therefore, it can be developed as an effective sensing platform for the detection of MP.

6.
J Conserv Dent ; 21(2): 198-204, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29674825

RESUMEN

AIM: This study aims to evaluate the microshear bond strength of zirconia-based ceramics with different resin cement systems and surface treatments. MATERIALS AND METHODS: Forty blocks of zirconia-based ceramic were prepared and embedded in polyvinyl chloride (PVC) tubes with acrylic resin. After polishing, the samples were washed in an ultrasonic bath and dried in an oven for 10 min. Half of the samples were subjected to sandblasting with aluminum oxide. Blocks were divided into four groups (n = 10) in which two resin cements were used as follows: (1) RelyX™ U100 with surface-polished zirconia; (2) RelyX™ U100 with surface-blasted zirconia; (3) Multilink with surface-polished zirconia; and 4) Multilink with surface-blasted zirconia. After performing these surface treatments, translucent tubes (n = 30 per group) were placed on the zirconia specimens, and resin cement was injected into them and light cured. The PVC tubes were adapted in a universal testing machine; a stiletto blade, which was bolted to the machine, was positioned on the cementation interface. The microshear test was performed at a speed of 0.5 mm/min. Failure mode was analyzed in an optical microscope and classified as adhesive, cohesive, or mixed. RESULTS: The null hypothesis of this study was rejected because there was a difference found between the resin cement and the surface treatment. There was a statistical difference (P < 0.005) in RelyX™ U100 with surface-blasted zirconia, in relation to the other three groups. For Multilink groups, there was no statistical difference between them. CONCLUSION: Self-adhesive resin cement showed a more significant tendency toward bond strength in the ceramic-based zirconium oxide grit-blasted surfaces.

7.
Proc Inst Mech Eng H ; 227(5): 510-22, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23637261

RESUMEN

The goal of the experiment outlined in this article is to improve upon noncemented methods of arthroplasty for clinical application in elderly patients. This was done by determining whether titanium implants with a novel nanostructured zirconia surface, which was created by ion beam-assisted deposition, would prevent impaired osseointegration of intramedullary implants in 1-year-old rats receiving a protein-deficient diet. Specifically, we asked whether the implant with the nanostructured zirconia surface would increase expression of markers of bone maturation within the remodeling of peri-implant woven bone. The control implants, which were made of commercially pure titanium, had a polished surface ex vivo but are known to acquire a microstructured titania surface in vivo. Ten 1-year-old rats received experimental implant (group A) and 10 had control (group B) implants. Ten 3-month-old rats received normal protein diet and the control implant (group C). Animals were euthanized 8 weeks after implantation, and transverse sections of femur-implant samples were used for histology, micro-computed tomography and immunohistochemical evaluations. In group B, the expression of α2ß1 and α5ß1 integrins, which are known to mediate osteoblast adhesion, glycosaminoglycans, heparan sulfate and chondroitin sulfate, was less than half of that in group C. Important to this study, the zirconia surface used in group A prevented these deficiencies. Therefore, these results indicate that nanostructured zirconia surface created on clinical implants by ion beam-assisted deposition may prevent impaired osseointegration in elderly patients by promoting quicker maturation of peri-implant woven bone.


Asunto(s)
Fémur/fisiología , Fémur/cirugía , Prótesis de Cadera , Nanopartículas del Metal/química , Oseointegración/fisiología , Titanio/química , Circonio/química , Animales , Materiales Biocompatibles Revestidos/química , Fémur/citología , Masculino , Nanopartículas del Metal/ultraestructura , Tamaño de la Partícula , Ratas , Ratas Sprague-Dawley , Propiedades de Superficie , Resultado del Tratamiento
8.
ImplantNews ; 10(1): 71-78, 2013. ilus
Artículo en Portugués | LILACS, BBO | ID: lil-731418

RESUMEN

A reposição de um incisivo lateral superior ausente pode representar um verdadeiro desafio estético. Dentre as opções disponíveis, a instalação de uma prótese unitária implantossuportada proporciona bons resultados, tanto esteticamente, quanto funcionalmente. Assim, o objetivo deste artigo foi apresentar um caso clínico, no qual um paciente com agenesia do incisivo lateral superior teve a reposição deste dente, através de prótese unitária implantossuportada com conexão protética cone-morse e pilar estético de zircônia. Como resultado, foi obtida uma restauração que supriu as necessidades estéticas e funcionais de um paciente jovem.


The replacement of a missing upper lateral incisor can be a real esthetic challenge. Among the available options, the insertion of a single implant-supported prosthesis can provide good results, both aesthetically and functionally. Thus, the purpose of this study is to present a case in which a patient with agenesis of upper lateral incisor received a Cone-Morse connection design with a screwed zirconia abutment and a final cemented crown. In this way, both funcional and esthetic demands were addressed for this young patient.


Asunto(s)
Humanos , Femenino , Adulto , Implantación Dental , Prótesis Dental de Soporte Implantado , Oseointegración
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