Objectives
To evaluate the peri‐implant tissue changes and esthetic outcomes of cemented and screw‐retained crowns of single‐tooth implants in the esthetic zone using zirconia abutments.
Material and ...methods
An electronic search was performed on nine databases. The risk‐of‐bias was assessed by the revised Cochrane risk‐of‐bias tool for randomized (RoB 2) and non‐randomized (ROBINS‐I) clinical trials. Marginal bone level change, soft tissue thickness, bleeding on probing, probing depth, survival rates of implants and crowns, complications, plaque and papilla indexes, and pink esthetic score data were extracted and analyzed. The certainty of evidence was accessed through the GRADE approach.
Results
Nine records were included and 7 were used in the meta‐analyses. Screw‐retained crowns presented greater marginal bone level change (MD −0.04 −0.08, −0.00 p = 0.04, I2 = 0%) compared to cemented crowns up to 1‐year. At 3 and 4 years no significant differences (p > 0.05) were observed. Soft tissue thickness did not differ between groups (p > 0.05). The bleeding on probing was higher in cemented group than in screw‐retained crowns at 1‐year (MD 0.17 0.08, 0.27 p = 0.0005, I2 = 0%), at medium‐term periods (3 and 4 years) no statistically significant differences (p > 0.05) were observed for this outcome. Probing depth, survival rates of implants and crowns, complications, and plaque index, as well as esthetic analysis using the papilla index and pink esthetic score did not differ statistically (p > 0.05) between both retention systems at short and medium‐term periods.
Conclusion
The connection system considering zirconia abutments presented no influence on peri‐implant parameters and esthetics evaluation for medium‐term periods (3 and 4 years).
Implant devices have = proven a successful treatment modality in reconstructive surgeries. However, increasing rates of peri-implant diseases demand further examination of their pathogenesis. ...Polymicrobial biofilm formation on titanium surfaces has been considered the main risk factor for inflammatory processes on tissues surrounding implant devices, which often lead to implant failure. To overcome microbial accumulation on titanium surfaces biofilm targeting strategies have been developed to modify the surface and incorporate antimicrobial coatings. Because antibiotics are widely used to treat polymicrobial infections, these agents have recently started to be incorporated on titanium surface. This review discusses the biofilm formation on titanium dental implants and key factors to be considered in therapeutic and preventative strategies. Moreover, a systematic review was conducted on coatings developed for titanium surfaces using different antibiotics. This review will also shed light on potential alternative strategies aiming to reduce microbial loads and control polymicrobial infection on implanted devices.
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•Polymicrobial biofilms are the main etiologic factor of implant-related infections•Titanium (Ti) biomaterial is a substrate for microbial accumulation•Antibiotic-loaded coating on titanium is a promising strategy this accumulation•These strategies need to improve drug releasing and are tested by polymicrobial models
Microbiofilms; Surface Science
Chagas disease (CD) affects approximately 6-7 million people worldwide, from which 30% develop chronic Chagas cardiomyopathy (CCC), usually after being asymptomatic for years. Currently available ...diagnostic methods are capable of adequately identifying infected patients, but do not provide information regarding the individual risk of developing the most severe form of the disease. The identification of biomarkers that predict the progression from asymptomatic or indeterminate form to CCC, may guide early implementation of pharmacological therapy. Here, six circulating microRNAs (miR-19a-3p, miR-21-5p, miR-29b-3p, miR-30a-5p, miR-199b-5p and miR-208a-3p) were evaluated and compared among patients with CCC (
= 28), CD indeterminate form (
= 10) and healthy controls (
= 10). MiR-19a-3p, miR-21-5p, and miR-29b-3p were differentially expressed in CCC patients when compared to indeterminate form, showing a positive correlation with cardiac dysfunction, functional class, and fibrosis, and a negative correlation with ejection fraction and left ventricular strain. Cardiac tissue analysis confirmed increased expression of microRNAs in CCC patients. In vitro studies using human cells indicated the involvement of these microRNAs in the processes of cardiac hypertrophy and fibrosis. Our study suggests that miRNAs are involved in the process of cardiac fibrosis and remodeling presented in CD and indicate a group of miRNAs as potential biomarkers of disease progression in CCC.
Objectives
To test the role of exopolysaccharide (EPS) polymers matrix to modulate the composition/virulence of biofilms growing on titanium (Ti) surfaces, the effect on antibiotic susceptibility, ...and whether a dual‐targeting therapy approach for disrupted EPS matrix could improve the antimicrobial effect.
Materials and Methods
A microcosm biofilm model using human saliva as inoculum was used, and the microbial composition was assessed by checkerboard DNA–DNA hybridization. EPS‐enriched biofilms virulence was tested using fibroblast monolayer. Povidone‐iodine (PI) was used as EPS‐targeting agent followed by amoxicillin + metronidazole antibiotic to reduce bacterial biomass using an in situ model.
Results
An EPS‐enriched environment, obtained by sucrose exposure, promoted bacterial accumulation and led to a dysbiosis on biofilms, favoring the growth of Streptococcus, Fusobacterium, and Campylobacter species and even strict anaerobic species related to peri‐implant infections, such as Porphyromonas gingivalis and Tannerella forsythia (~3‐fold increase). EPS‐enriched biofilm transitioned from a commensal aerobic to a pathogenic anaerobic profile. EPS increased biofilm virulence promoting higher host cell damage and reduced antimicrobial susceptibility, but the use of a dual‐targeting approach with PI pre‐treatment disrupted EPS matrix scaffold, increasing antibiotic effect on in situ biofilms.
Conclusion
Altogether, our data provide new insights of how EPS matrix creates an environment that favors putative pathogens growth and shed light to a promising approach that uses matrix disruption as initial step to potentially improve implant‐related infections treatment.
Titanium-zirconium (Ti-Zr) alloy has been widely used as a biomaterial for implant devices, and it is commonly treated by sandblasting followed by acid etching (SLA) to improve biological responses. ...Although protein adsorption is the first biological response, the effect of this SLA treatment on the proteomic profile of proteins adsorbed from saliva and blood plasma has not been tested. In this study, the proteomic profile was evaluated by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Streptococcus sanguinis was used to test whether the protein layer affects bacterial adhesion. SLA treatment affected the proteomic profile, showing exclusive proteins adsorbed from saliva (14) and plasma (3). However, both groups exhibited close patterns of intensity for common proteins, molecular functions and biological processes mediated by proteins. Interestingly, Ti-Zr
SLA
showed higher bacterial adhesion (∼1.9 fold over) for the surface coated with plasma proteins. Therefore, SLA treatment of Ti-Zr alloy changed the proteomic profile, which may affect bacterial adhesion.
The aim of the study was to evaluate several mechanical and chemical decontamination methods associated with a newly introduced biofilm matrix disruption strategy for biofilm cleaning and ...preservation of implant surface features.
Titanium (Ti) discs were obtained by additive manufacturing. Polymicrobial biofilm-covered Ti disc surfaces were decontaminated with mechanical Ti curette, Teflon curette, Ti brush, water-air jet device, and Er:YAG laser or chemical iodopovidone (PVPI) 0.2% to disrupt the extracellular matrix, along with amoxicillin; minocycline; tetracycline; H
O
3%; chlorhexidine 0.2%; NaOCl 0.95%; hydrocarbon-oxo-borate-based antiseptic protocols. The optimal in vitro mechanical/chemical protocol was then tested in combination using an in vivo biofilm model with intra-oral devices.
Er:YAG laser treatment displayed optimum surface cleaning by biofilm removal with minimal deleterious damage to the surface, smaller Ti release, good corrosion stability, and improved fibroblast readhesion. NaOCl 0.95% was the most promising agent to reduce in vitro and in vivo biofilms and was even more effective when associated with PVPI 0.2% as a pre-treatment to disrupt the biofilm matrix. The combination of Er:YAG laser followed by PVPI 0.2% plus NaOCl 0.95% promoted efficient decontamination of rough Ti surfaces by disrupting the biofilm matrix and killing remnants of in vivo biofilms formed in the mouth (the only protocol to lead to ~99% biofilm eradication).
Er:YAG laser + PVPI 0.2% + NaOCl 0.95% can be a reliable decontamination protocol for Ti surfaces, eliminating microbial biofilms without damaging the implant surface.
The oral cavity presents a highly diverse community of microorganisms due to the unique environmental conditions for microbial adhesion and growth ....
The COVID-19 pandemic, caused by the rapid global spread of the novel coronavirus (SARS-CoV-2), has caused healthcare systems to collapse and led to hundreds of thousands of deaths. The clinical ...spectrum of COVID-19 is not only limited to local pneumonia but also represents multiple organ involvement, with potential for systemic complications. One year after the pandemic, pathophysiological knowledge has evolved, and many therapeutic advances have occurred, but mortality rates are still elevated in severe/critical COVID-19 cases. Mesenchymal stromal cells (MSCs) can exert immunomodulatory, antiviral, and pro-regenerative paracrine/endocrine actions and are therefore promising candidates for MSC-based therapies. In this review, we discuss the rationale for MSC-based therapies based on currently available preclinical and clinical evidence of safety, potential efficacy, and mechanisms of action. Finally, we present a critical analysis of the risks, limitations, challenges, and opportunities that place MSC-based products as a therapeutic strategy that may complement the current arsenal against COVID-19 and reduce the pandemic's unmet medical needs.
Artificial bone grafting materials such as collagen are gaining interest due to the ease of production and implantation. However, collagen must be supplemented with additional coating materials for ...improved osteointegration. Here, we report room-temperature atomic layer deposition (ALD) of MgO, a novel method to coat collagen membranes with MgO. Characterization techniques such as X-ray photoelectron spectroscopy, Raman spectroscopy, and electron beam dispersion mapping confirm the chemical nature of the film. Scanning electron and atomic force microscopies show the surface topography and morphology of the collagen fibers were not altered during the ALD of MgO. Slow release of magnesium ions promotes bone growth, and we show the deposited MgO film leaches trace amounts of Mg when incubated in phosphate-buffered saline at 37 °C. The coated collagen membrane had a superhydrophilic surface immediately after the deposition of MgO. The film was not toxic to human cells and demonstrated antibacterial properties against bacterial biofilms. Furthermore, in vivo studies performed on calvaria rats showed MgO-coated membranes (200 and 500 ALD) elicit a higher inflammatory response, leading to an increase in angiogenesis and a greater bone formation, mainly for Col-MgO500, compared to uncoated collagen. Based on the characterization of the MgO film and in vitro and in vivo data, the MgO-coated collagen membranes are excellent candidates for guided bone regeneration.
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•Room-temperature atomic layer deposition of magnesium oxide enables use of temperature-sensitive collagen as substrate.•MgO-coated collagen has controlled degradation rate of Mg2+ ion in aqueous environment which promotes bone growth.•In vitro and in vivo studies confirm MgO-coated collagen can be used as artificial bone graft material.•Bone regeneration through magnesium oxide deposition promotes osteopromotive property favorable for use in clinical practice.
Chagas disease, caused by the parasite
(
), remains a serious public health problem for which there is no effective treatment in the chronic stage. Intense cardiac fibrosis and inflammation are ...hallmarks of chronic Chagas disease cardiomyopathy (CCC). Previously, we identified upregulation of circulating and cardiac miR-21, a pro-fibrotic microRNA (miRNA), in subjects with CCC. Here, we explored the potential role of miR-21 as a therapeutic target in a model of chronic Chagas disease. PCR array-based 88 microRNA screening was performed in heart samples obtained from C57Bl/6 mice chronically infected with
and serum samples collected from CCC patients. MiR-21 was found upregulated in both human and mouse samples, which was corroborated by an in silico analysis of miRNA-mRNA target prediction. In vitro miR-21 functional assays (gain-and loss-of-function) were performed in cardiac fibroblasts, showing upregulation of miR-21 and collagen expression upon transforming growth factor beta 1 (TGFβ1) and
stimulation, while miR-21 blockage reduced collagen expression. Finally, treatment of
-infected mice with locked nucleic acid (LNA)-anti-miR-21 inhibitor promoted a significant reduction in cardiac fibrosis. Our data suggest that miR-21 is a mediator involved in the pathogenesis of cardiac fibrosis and indicates the pharmacological silencing of miR-21 as a potential therapeutic approach for CCC.
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