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1.
Biomedicines ; 9(11)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34829786

RESUMO

The crosstalk among cancer cells (CCs) and stromal cells within the tumor microenvironment (TME) has a prominent role in cancer progression. The significance of endothelial cells (ECs) in this scenario relies on multiple vascular functions. By forming new blood vessels, ECs support tumor growth. In addition to their angiogenic properties, tumor-associated ECs (TECs) establish a unique vascular niche that actively modulates cancer development by shuttling a selected pattern of factors and metabolites to the CC. The profile of secreted metabolites is strictly dependent on the metabolic status of the cell, which is markedly perturbed in TECs. Recent evidence highlights the involvement of heme metabolism in the regulation of energy metabolism in TECs. The present study shows that interfering with endothelial heme metabolism by targeting the cell membrane heme exporter Feline Leukemia Virus subgroup C Receptor 1a (FLVCR1a) in TECs, resulted in enhanced fatty acid oxidation (FAO). Moreover, FAO-derived acetyl-CoA was partly consumed through ketogenesis, resulting in ketone bodies (KBs) accumulation in FLVCR1a-deficient TECs. Finally, the results from this study also demonstrate that TECs-derived KBs can be secreted in the extracellular environment, inducing a metabolic rewiring in the CC. Taken together, these data may contribute to finding new metabolic vulnerabilities for cancer therapy.

2.
Polymers (Basel) ; 13(22)2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34833321

RESUMO

The surface functionalisation of high-density polyethylene (HDPE) and HDPE/alumina-toughened zirconia (ATZ) surfaces with chitosan via electron-beam (EB) irradiation technique was exploited for preparing materials suitable for biomedical purposes. ATR-FTIR analysis and wettability measurements were employed for monitoring the surface changes after both irradiation and chitosan grafting reaction. Interestingly, the presence of ATZ loadings beyond 2 wt% influenced both the EB irradiation process and the chitosan functionalisation reaction, decreasing the oxidation of the surface and the chitosan grafting. The EB irradiation induced an increase in Young's modulus and a decrease in the elongation at the break of all analysed systems, whereas the tensile strength was not affected in a relevant way. Biological assays indicated that electrostatic interactions between the negative charges of the surface of cell membranes and the -NH3+ sites on chitosan chains promoted cell adhesion, while some oxidised species produced during the irradiation process are thought to cause a detrimental effect on the cell viability.

3.
Biomedicines ; 9(9)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34572271

RESUMO

The use of mesenchymal stem cells (MSCs) for regenerative purposes has become common in a large variety of diseases. In the dental and maxillofacial field, there are emerging clinical needs that could benefit from MSC-based therapeutic approaches. Even though MSCs can be isolated from different tissues, such as bone marrow, adipose tissue, etc., and are known for their multilineage differentiation, their different anatomical origin can affect the capability to differentiate into a specific tissue. For instance, MSCs isolated from the oral cavity might be more effective than adipose-derived stem cells (ASCs) for the treatment of dental defects. Indeed, in the oral cavity, there are different sources of MSCs that have been individually proposed as promising candidates for tissue engineering protocols. The therapeutic strategy based on MSCs can be direct, by using cells as components of the tissue to be regenerated, or indirect, aimed at delivering local growth factors, cytokines, and chemokines produced by the MSCs. Here, the authors outline the major sources of mesenchymal stem cells attainable from the oral cavity and discuss their possible usage in some of the most compelling therapeutic frontiers, such as periodontal disease and dental pulp regeneration.

4.
Clin Implant Dent Relat Res ; 23(4): 562-567, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34219356

RESUMO

BACKGROUND: Although full-arch immediately loaded rehabilitations are widely used nowadays, little information is available on which implant/abutment connection is the most suitable in this type of treatment. PURPOSE: The aim of the present multicentric split-mouth clinical trial was to compare the clinical outcomes of two different implant-abutment connections applied in full-arch immediate loading rehabilitations: external hexagon connection (EHC) versus internal hexagon connection (IHC). MATERIALS AND METHODS: Twenty patients were rehabilitated with immediately loaded fixed full-arch rehabilitations. All the implants presented the same macro- and micro-topography but different implant/abutment connection. IHC were used in one randomly selected side of the jaw and EHC in the other side. Outcome measures were implant survival rate, peri-implant marginal bone loss (MBL), plaque index (PI), probing depth (PD), and bleeding on probing (BoP) evaluated at 3, 6, 12, and 36-month post-loading. Any technical and biological complication was recorded. Kaplan-Meier procedure and linear mixed model were used to perform statistical analysis. RESULTS: Forty-three EHC and 40 IHC implants were inserted. No patients dropped out and two implants failed in the first 6 months. The CSR was 97.7% for EHC and 97.5% for IHC implants. No statistically significant differences were found among the two groups for any of the parameters at any time point. At the 36-month follow-up visit a slight difference was found in MBL with a mean value of 1.7 mm in the EHC and of 1.9 mm in the IHC group (p = 0.355). No biologic complications were identified. Seven loosed abutment screws were identified in the entire follow-up period, two in the EHC, and five in the IHC group without a statistically significant difference (p = 0.394). CONCLUSIONS: After 36 months in function, both internal and external hexagon connections provided good clinical outcomes and were not associated with any significant difference.


Assuntos
Implantes Dentários , Carga Imediata em Implante Dentário , Índice de Placa Dentária , Prótese Dentária Fixada por Implante , Seguimentos , Humanos , Boca , Resultado do Tratamento
5.
Leg Med (Tokyo) ; 53: 101934, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34225094

RESUMO

Higher resolution than common computed tomography has been reached through Micro-Computed Tomography (micro-CT) on small samples. Emerging forensic applications of micro-CT are the study of fetal/infant organs and whole fetuses, and their two/three-dimension reconstruction; it allows: to facilitate pathologists' role in the identification of causes of fetal stillbirth and of infant death; to create digital two and/or three-dimension representations of fetal/infant organs and whole fetuses which can be easily discussed in civil and/or penal courts. Micro-CT reconstructs cardiac anatomy of animal and human sample. There are no studies that are specifically aimed to evaluate possible effects of micro-CT processing on cardiac microscopic evaluation. This study analyzed microscopic effects of micro-CT processing on human-fetal-hearts. After processing with Lugol-solution or Microfil-MV-122-injection in coronary branches, fetal hearts underwent micro-CT scan. Then, hearts were microscopically analyzed using hematoxylin/eosin, trichrome, immunohistochemistry (IHC) for actin-protein, and IHC for desmin-intermediate-filament stains. In all cases staining was present in all fields. In all slides, disarranged myocardial proteins with increase of inter filaments and inter cellular spaces was reported. This manuscript allowed to observe post micro-CT appropriate staining and antigenic reactivity, and to identify cytoarchitecture modifications that could compromise slides' microscopic evaluation. It also highlighted a possible role of micro-CT determining this cytoarchitecture phenomenon.


Assuntos
Feto , Coração , Animais , Feto/diagnóstico por imagem , Medicina Legal , Coração/diagnóstico por imagem , Humanos , Coloração e Rotulagem , Microtomografia por Raio-X
6.
Biomedicines ; 9(3)2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33800030

RESUMO

Mesenchymal stem cells (MSCs) can be harvested from different sites in the oral cavity, representing a reservoir of cells useful for regenerative purposes. As direct comparisons between at least two types of MSCs deriving from the same patient are surprisingly rare in scientific literature, we isolated and investigated the osteoinductive potential of dental pulp stem cells (DPSCs) and buccal fat pad stem cells (BFPSCs). MSCs were isolated from the third molar dental pulp and buccal fat pads of 12 patients. The number of viable cells was quantified through manual count. Proliferation and osteodifferentiation assays, flow cytometry analysis of cell phenotypes, and osteocalcin release in vitro were performed. The isolation of BFPSCs and DPSCs was successful in 7 out of 12 (58%) and 3 out of 12 (25%) of retrieved samples, respectively. The yield of cells expressing typical stem cell markers and the level of proliferation were higher in BFPSCs than in DPSCs. Both BFP-SCs and DPSCs differentiated into osteoblast-like cells and were able to release a mineralized matrix. The release of osteocalcin, albeit greater for BFPSCs, did not show any significant difference between BFPSCs and DPSCs. The yield of MSCs depends on their site of origin as well as on the protocol adopted for their isolation. Our data show that BFP is a valuable source for the derivation of MSCs that can be used for regenerative treatments.

7.
Int J Oral Maxillofac Implants ; 36(2): 242-247, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33909713

RESUMO

PURPOSE: Bone graft materials and soft tissue allografts are widely used in clinical practice to counteract physiologic postextraction site tridimensional shrinkage. The aim of this study was to test if plasma of argon treatment could have a bioactivation effect on hard and soft tissue scaffolds in clinical usage. MATERIALS AND METHODS: Forty-eight bovine bone matrix and porcine collagen samples were subdivided into two groups (test and control) of 12 samples each. The test group was treated with argon plasma (10 W, 1 bar for 12 minutes), while the control group was left untreated. Immediate cell adhesion and a proliferation assay at 72 hours were performed in the perfusion chamber of a bioreactor. Additionally, micro-CT analysis was performed on the treated and untreated scaffolds, before and after soaking in cell culture medium (four samples). RESULTS: Osteoblasts seeded on plasma-treated bone matrix significantly increased the adhesion level compared with the untreated sample (43,144.3 ± 12,442.9 vs 21,736 ± 77,27.1; P = .0083). However, 3-day proliferation tests could not achieve significant differences between groups (105,715.5 ± 21,751.5 vs 107,108.6 ± 19,343.4; P = .998). No differences were measured on fibroblast adhesion on the collagen matrix in both conditions. Plasma of argon treatment and soaking in cell culture medium did not affect the bone matrix samples. The structure of collagen matrix samples was unaltered after plasma treatment, but became enlarged after soaking. CONCLUSION: Plasma of argon may be useful to biofunctionalize bone grafts, although benefits seemed to disappear after 3 days. No biologic response was detected on collagen matrix scaffolds. In vivo studies are needed to draw final clinical conclusions.


Assuntos
Matriz Óssea , Gases em Plasma , Animais , Argônio , Transplante Ósseo , Bovinos , Colágeno , Suínos , Tecidos Suporte
8.
Int J Mol Sci ; 22(8)2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33920046

RESUMO

SmartBone® (SB) is a biohybrid bone substitute advantageously proposed as a class III medical device for bone regeneration in reconstructive surgeries (oral, maxillofacial, orthopedic, and oncology). In the present study, a new strategy to improve SB osteoinductivity was developed. SB scaffolds were loaded with lyosecretome, a freeze-dried formulation of mesenchymal stem cell (MSC)-secretome, containing proteins and extracellular vesicles (EVs). Lyosecretome-loaded SB scaffolds (SBlyo) were prepared using an absorption method. A burst release of proteins and EVs (38% and 50% after 30 min, respectively) was observed, and then proteins were released more slowly with respect to EVs, most likely because they more strongly adsorbed onto the SB surface. In vitro tests were conducted using adipose tissue-derived stromal vascular fraction (SVF) plated on SB or SBlyo. After 14 days, significant cell proliferation improvement was observed on SBlyo with respect to SB, where cells filled the cavities between the native trabeculae. On SB, on the other hand, the process was still present, but tissue formation was less organized at 60 days. On both scaffolds, cells differentiated into osteoblasts and were able to mineralize after 60 days. Nonetheless, SBlyo showed a higher expression of osteoblast markers and a higher quantity of newly formed trabeculae than SB alone. The quantification analysis of the newly formed mineralized tissue and the immunohistochemical studies demonstrated that SBlyo induces bone formation more effectively. This osteoinductive effect is likely due to the osteogenic factors present in the lyosecretome, such as fibronectin, alpha-2-macroglobulin, apolipoprotein A, and TGF-ß.


Assuntos
Matriz Óssea/química , Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/farmacologia , Transplante de Células-Tronco Mesenquimais , Animais , Substitutos Ósseos/química , Bovinos , Diferenciação Celular/efeitos dos fármacos , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Vesículas Extracelulares/química , Vesículas Extracelulares/genética , Humanos , Células-Tronco Mesenquimais/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Procedimentos Cirúrgicos Reconstrutivos/métodos
9.
BMC Oral Health ; 20(1): 271, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028288

RESUMO

BACKGROUND: Fully adjustable articulators and pantographs record and reproduce individual mandibular movements. Although these instruments are accurate, they are operator-dependant and time-consuming. Pantographic recording is affected by inter and intra operator variability in the individuation of clinical reference points and afterwards in reading pantographic recording themselves. Finally only border movements can be reproduced. METHODS: Bionic Jaw Motion system is based on two components: a jaw movement analyzer and a robotic device that accurately reproduces recorded movements. The jaw movement analyzer uses an optoelectronic motion system technology made of a high frequency filming camera that acquires 140frames per second and a custom designed software that recognizes and determines the relative distance at each point in time of markers with known geometries connected to each jaw. Circumferential modified retainers connect markers and do not cover any occlusal surfaces neither obstruct occlusion. The recording process takes 5 to 10 s. Mandibular movement performance requires six degrees of freedom of movement, 3 rotations and 3 translations. Other robots are based on the so-called delta mechanics that use several parallel effectors to perform desired movements in order to decompose a complex trajectory into multiple more simple linear movements. However, each parallel effector introduces mechanical inter-component tolerances and mathematical transformations that are required to transform a recorded movement into the combination of movements to be performed by each effector. Bionic Jaw Motion Robot works differently, owing to three motors that perform translational movements and three other motors that perform rotations as a gyroscope. This configuration requires less mechanical components thus reducing mechanical tolerances and production costs. Both the jaw movement analyzer and the robot quantify the movement of the mandible as a rigid body with six degrees of freedom. This represents an additional advantage as no mathematical transformation is needed for the robot to reproduce recorded movements. RESULTS: Based on the described procedure, Bionic Jaw Motion provide accurate recording and reproduction of maxillomandibular relation in static and dynamic conditions. CONCLUSION: This robotic system represents an important advancement compared to available analogical and digital alternatives both in clinical and research contexts for cost reduction, precision and time saving opportunities.


Assuntos
Robótica , Articuladores Dentários , Registro da Relação Maxilomandibular , Mandíbula , Movimento , Reprodução
10.
Int J Mol Sci ; 21(19)2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32977633

RESUMO

Reconstruction of bony defects is challenging when conventional grafting methods are used because of their intrinsic limitations (biological cost and/or biological properties). Bone regeneration techniques are rapidly evolving since the introduction of three-dimensional (3D) bioprinting. Bone tissue engineering is a branch of regenerative medicine that aims to find new solutions to treat bone defects, which can be repaired by 3D printed living tissues. Its aim is to overcome the limitations of conventional treatment options by improving osteoinduction and osteoconduction. Several techniques of bone bioprinting have been developed: inkjet, extrusion, and light-based 3D printers are nowadays available. Bioinks, i.e., the printing materials, also presented an evolution over the years. It seems that these new technologies might be extremely promising for bone regeneration. The purpose of the present review is to give a comprehensive summary of the past, the present, and future developments of bone bioprinting and bioinks, focusing the attention on crucial aspects of bone bioprinting such as selecting cell sources and attaining a viable vascularization within the newly printed bone. The main bioprinters currently available on the market and their characteristics have been taken into consideration, as well.


Assuntos
Bioimpressão , Regeneração Óssea , Substitutos Ósseos/química , Impressão Tridimensional/instrumentação , Engenharia Tecidual , Tecidos Suporte/química , Bioimpressão/instrumentação , Bioimpressão/métodos , Humanos , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos
11.
J Cell Physiol ; 235(12): 10110-10115, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32567069

RESUMO

Here we present a new Fiji/ImageJ2 plugin called Multiparametric Morphometric Analysis of EUcaryotic cellS (MORPHEUS), designed for the automated evaluation of cell morphometry from images acquired by fluorescence microscopy. MORPHEUS works with sampling distributions to learn-in an unsupervised manner and by a nonparametric approach-how to recognize the cells suitable for subsequent analysis. Afterward, the algorithm performs the evaluation of the most relevant cell-shape descriptors over the full set of detected cells. Optionally, also the extraction of nucleus features and a double-scale analysis of orientation can be performed. The whole algorithm is implemented as a one-click procedure, thus minimizing the user's intervention. By reducing biases and errors of human origin, MORPHEUS is intended to be a useful tool to enhance reproducibility in the bioimage analysis.


Assuntos
Núcleo Celular/ultraestrutura , Processamento de Imagem Assistida por Computador/métodos , Microscopia de Fluorescência , Software , Algoritmos , Eucariotos/ultraestrutura , Humanos
12.
Ann Anat ; 230: 151489, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32165207

RESUMO

BACKGROUND: Plasma of argon was demonstrated to improve protein and cell adhesion on implant surface. On the other hand, increased surface energy and hydrophilicity could potentially amplify the risks of implant surface contamination during clinical phases, risks that have not yet been evaluated in Literature. The aim of the present in vitro study was to verify if Plasma treatment could alter the implant surface characteristics and its ability to remain sterile. MATERIALS AND METHODS: Implants from 9 brands were collected (n=11). One implant for each company was used for SEM surface analysis. To perform the microbiological analysis, ten implants from each company were used and randomly split by allocation either in test or control group. To replicate the surgical work flow, both test and control samples were left 60s in clinical environment. Bacterial growth analysis was performed. Optical density at 600nm was measured as readout of bacterial growth and colony forming unit (CFU) after 24h was evaluated. Statistical analysis was performed by using the Wilcoxon Mann Whitney test. A p-value lower than 0.05 was considered significant. RESULTS: SEM analysis revealed different categories of implant surface roughness. The optical density confirmed a readout of bacterial growth between 4 and 7 with no significant differences within groups. The number of CFU/ml for each measured sample (test and control) was lower than 102 and failed to present significant differences. CONCLUSION: Surface activation using plasma of argon did not affect the degree of implant contamination, allowing to maintain a substantial sterility of the implant independently of its morphology. This may allow in the next future the use of bioactivation through plasma of argon to exploit the superhydrophilicity deriving from this biophysical process.


Assuntos
Argônio/farmacologia , Implantes Dentários , Implantes Dentários/microbiologia , Microscopia Eletrônica de Varredura , Distribuição Aleatória , Propriedades de Superfície
13.
Int J Mol Sci ; 21(6)2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32168919

RESUMO

BACKGROUND: Attaining an effective mucosal attachment to the transmucosal part of the implant could protect the peri-implant bone. AIM: To evaluate if chair side surface treatments (plasma of Argon and ultraviolet light) may affect fibroblast adhesion on different titanium surfaces designed for soft tissue healing. METHODS: Grade 5 titanium discs with four different surface topographies were subdivided into 3 groups: argon-plasma; ultraviolet light, and no treatment. Cell morphology and adhesion tests were performed at 20 min, 24 h, and 72 h. RESULTS: Qualitative observation of the surfaces performed at the SEM was in accordance with the anticipated features. Roughness values ranged from smooth (MAC Sa = 0.2) to very rough (XA Sa = 21). At 20 min, all the untreated surfaces presented hemispherical cells with reduced filopodia, while the cells on treated samples were more spread with broad lamellipodia. However, these differences in spreading behavior disappeared at 24 h and 72 h. Argon-plasma, but not UV, significantly increased the number of fibroblasts independently of the surface type but only at 20 min. Statistically, there was no surface in combination with a treatment that favored a greater cellular adhesion. CONCLUSIONS: Data showed potential biological benefits of treating implant abutment surfaces with the plasma of argon in relation to early-stage cell adhesion.


Assuntos
Argônio/farmacologia , Fibroblastos/citologia , Titânio/química , Adesão Celular , Proliferação de Células/fisiologia , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Humanos , Técnicas In Vitro , Propriedades de Superfície
14.
Clin Oral Investig ; 24(8): 2611-2623, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31748982

RESUMO

BACKGROUND: The osteoconductive properties of bone grafting materials represent one area of research for the management of bony defects found in the fields of periodontology and oral surgery. From a physico-chemical aspect, the wettability of the graft has been demonstrated to be one of the most important factors for new bone formation. It is also well-known that argon plasma treatment (PAT) and ultraviolet irradiation (UV) may increase the surface wettability and, consequently, improve the regenerative potential of the bone grafts. Therefore, the aim of the present in vitro study was to evaluate the effect of PAT and UV treatment on the osteoconductive potential of various bone grafts. MATERIALS AND METHODS: The following four frequently used bone grafts were selected for this study: synthetic hydroxyapatite (Mg-HA), biphasic calcium phosphate (BCP), cancellous and cortical xenogenic bone matrices (CaBM, CoBM). Sixty-six serially numbered disks 10 mm in diameter were used for each graft material and randomly assigned to the following three groups: test 1 (PAT), test 2 (UV), and control (no treatment). Six samples underwent topographic analysis using SEM pre- and post-treatments to evaluate changes in surface topography/characteristics. Additionally, cell adhesion and cell proliferation were evaluated at 2 and 72 h respectively following incubation in a three-dimensional culture system utilizing a bioreactor. Furthermore, the effects of PAT and UV on immune cells were assessed by measuring the viability of human macrophages at 24 h. RESULTS: The topographic analysis showed different initial morphologies of the commercial biomaterials (e.g., Mg-HA and BCP showed flat morphology; BM samples were extremely porous with high roughness). The surface analysis following experimental treatments did not demonstrate topographical difference when compared with controls. Investigation of cells demonstrated that PAT treatment significantly increased cell adhesion of all 4 evaluated bone substitutes, whereas UV failed to show any statistically significant differences. The viability test revealed no differences in terms of macrophage adhesion on any of the tested surfaces. CONCLUSION: Within their limitations, the present results suggest that treatment of various bone grafting materials with PAT appears to enhance the osteoconductivity of bone substitutes in the early stage by improving osteoblast adhesion without concomitantly affecting macrophage viability. CLINICAL RELEVANCE: Treatment of bone grafts with PAT appears to result in faster osseointegration of the bone grafting materials and may thus favorably influence bone regeneration.


Assuntos
Regeneração Óssea , Substitutos Ósseos , Argônio , Materiais Biocompatíveis , Transplante Ósseo , Durapatita , Humanos , Gases em Plasma
15.
Front Physiol ; 10: 1291, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681005

RESUMO

The synergistic crosstalk between osteodifferentiating stem cells and endothelial cells (ECs) gained the deserved consideration, shedding light on the role of angiogenesis for bone formation and healing. A deep understanding of the molecular basis underlying the mutual influence of mesenchymal stem cells (MSCs) and ECs in the osteogenic process may help improve greatly bone regeneration. Here, the authors demonstrated that osteodifferentiating MSCs co-cultured with ECs promote angiogenesis and ECs recruitment. Moreover, through the use of 3D co-culture systems, we showed that ECs are in turn able to further stimulate the osteodifferentiation of MSCs, thus enhancing bone production. These findings highlighted the existence of a virtuous loop between MSCs and ECs that is central to the osteogenic process. Unraveling the molecular mechanisms governing the functional interaction MSCs and ECs holds great potential in the field of regenerative medicine.

16.
Minerva Stomatol ; 68(4): 177-182, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31357851

RESUMO

BACKGROUND: Peri-implantitis or implant infection is a biologic complication involving soft and hard tissues around implants. The prevalence of the disease was recently estimated between 12% and 14% according to studies dealing with the private practice, which is also consistent with university statistics. Different methods were presented to minimize or even to remove biofilm from contaminated surfaces completely. Chemical and air-abrasive treatments have been shown to be able to disrupt biofilm. Chemical cleaning solution in combination with mechanical debridement is ineffective to eliminate bacterial biofilm. Lasers and photodynamic therapy presented inconsistent results. Interestingly, implantoplasty remains a preferred way to remove infected contaminants. When re-osseointegration of these treated contaminated implant surfaces was assessed, the quality of the implant surface after decontamination dictates the outcome. No matter the type of intervention implemented to counteract peri-implantitis, implant failure sometimes remains an unavoidable outcome. In this in-vitro report, the authors propose an automated EDS analysis of the whole dental implant surface to determine the percentage directly involved by the bacterial biofilm on failed fixtures. METHODS: Samples morphology was studied using a Scanning Electron Microscope (SEM, Zeiss Evo 50 XVP with LaB6 source). The instrument is endowed with detectors for secondary and backscattered electrons collection, as well as energy dispersion spectroscopy (EDS) analyzer for elemental analysis. All the materials were observed using 10kV of voltage. Samples, soon after being collected and fixed in 4% paraformaldehyde, were covered with a golden layer of about 10 nm in order to avoid charge accumulation during SEM-EDS analysis. Automated EDS mapping was obtained on the entire surface. RESULTS: On the samples analyzed (N.=10), the mean surface covered by bacterial biofilm was 79.3±7.6% (Mean±95% CI) based on the percentage of titanium, oxygen, and phosphorous. As a control, direct observation of the samples was also performed owing to SEM images finding an optimal correlation between the automatic EDS mapping and human-driven quantification of the bacterial biofilm. CONCLUSIONS: Based on these preliminary data, EDS automatic mapping may be considered an exciting method to analyze failed implants. Furthermore, the possible future applications in this field, once the bacteria have been identified, could involve a more specific treatment with the aim of remove infected contaminants on the implant surfaces.


Assuntos
Implantes Dentários , Peri-Implantite , Biofilmes , Humanos , Análise Espectral , Propriedades de Superfície , Inquéritos e Questionários , Titânio
17.
Int J Oral Implantol (Berl) ; 12(2): 169-179, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31090748

RESUMO

PURPOSE: To evaluate if a different morphology of the implant-abutment connection (internal vs. external hexagon) is able to condition the behaviour of hard and soft peri-implant tissues. MATERIALS AND METHODS: Twenty patients with significantly unfavourable prognoses for their residual maxillary or mandibular dentitions were selected and rehabilitated with immediately loaded fixed full-arch rehabilitations in two different centres. Four to six implants with identical macro- and micro-topography were inserted in each arch: external hexagon implants (EHC) in one randomly selected side of the dental arch and internal hexagon implants (IHC) in the other side. Primary outcome measures were the success rates of the implants and prostheses. Any technical and biological complication was recorded. Secondary outcome measures were: peri-implant marginal bone level (MBL) changes, Plaque Index (PI), probing depth (PD) and bleeding on probing (BoP), evaluated at implant insertion and at 3, 6 and 12 months post-loading. RESULTS: Forty-three EHC and 40 IHC implants were inserted in 20 patients. No patients dropped out. Two implants failed; one IHC after 3 months and one EHC after 6 months in two different patients (difference IHC vs. EHC at patient level: 0.06%; 95% CI: -1.9 to 2.1; P = 0.99). No prosthesis failed. No biological complications were identified and three loose prosthetic abutment screws were identified in three different patients (two EHC and one IHC); difference at patient level IHC vs. EHC: 2.1% (95% CI: -0.8 to 5; P = 0.43). Overall marginal bone loss was not significantly different between the two treatment groups (EHC vs. IHC) at any time point. The mean difference of bone levels between EHC and IHC was 0.25 mm (95% CI: -0.18 to 0.69) at implant placement. Mean difference between IHC and EHC was -0.01 mm (95% CI: -0.34 to 0.36) at 3 months, 0.13 mm (95% CI: -0.48 to 0.22) at 6 months and 0.11 mm (95% CI: -0.45 to 0.25) at 12 months. All the implants showed good periodontal health at the 1-year-in-function visit, with no statistically significant differences between groups. At 12 months mean (± standard deviation) PI was 2 (± 1.5) for the EHC and 1.85 (± 1.58) for the IHC group (P = 0.57) with a mean difference between the two groups of 0.15 (95% CI: -0.56 to 0.85). Mean PD was 2.23 mm (± 0.52) for the EHC and 2.10 mm (± 0.39) for the IHC group (P = 0.39), with a mean difference between the two groups of 0.12 mm (95% CI: -0.08 to 0.33). At 12 months 41.4% of EHC and 43.6% of IHC implants presented no BoP (mean difference: -2.2%, 95% CI: -24.0 to 19.3; P = 0.51). No significant effect of centres over all outcomes was identified (P = 0.71 for MBL, P = 0.14 for PI, P = 0.14 for PD and P = 0.20 for BoP). CONCLUSIONS: On the basis of the present trial the two types of implant connections were clinically reliable. After 12 months in function, both implants provided good clinical outcomes, without statistically significant differences between the two groups.


Assuntos
Implantação Dentária Endo-Óssea , Implantes Dentários , Maxila , Índice de Placa Dentária , Humanos , Boca , Resultado do Tratamento
18.
J Biomed Mater Res A ; 107(1): 67-70, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30358073

RESUMO

Plasma of argon was demonstrated to improve protein and cell adhesion on bone grafts. On the other hand, increased surface energy and hydrophilicity could potentially amplify the risks of graft surface contamination in a clinical environment. The aim of the present study was to in vitro verify if the plasma of argon treatment could alter the graft characteristics affecting its ability to remain sterile. Six graft materials produced by different company were selected for this study, and randomly split by allocation either in the test (Plasma of argon treatment for 20') or the control group (only removed from the plastic sterile vials). To replicate the surgical work flow, both test and control samples were left 2 min in the clinical environment simulated conditions. Samples were therefore transferred in a Biosafety level 2 culture room. Bacterial growth analysis was performed. Optical density at 600 nm was measured as readout of bacterial growth and, after 24 hours, colony forming unit (CFU) was evaluated. Statistical analysis was performed by using the ordinary one-way ANOVA. The optical density confirmed no significant differences within groups and the number of CFU/ml for each measured sample (test and control) failed to present significant differences. Data from the present study highlighted that surface activation using plasma of argon did not affect the degree of contamination of the bone grafts, allowing to maintain a required sterility of the surface. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 67-70, 2019.


Assuntos
Argônio/farmacologia , Bactérias/crescimento & desenvolvimento , Interface Osso-Implante/microbiologia , Desinfetantes/farmacologia , Desinfecção , Gases em Plasma/farmacologia , Humanos
19.
Int Orthop ; 43(1): 15-23, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30311059

RESUMO

PURPOSE: Osteoarthritis (OA) is characterized by articular cartilage degeneration and subchondral bone sclerosis. OA can benefit of non-surgical treatments with collagenase-isolated stromal vascular fraction (SVF) or cultured-expanded mesenchymal stem cells (ASCs). To avoid high manipulation of the lipoaspirate needed to obtain ASCs and SVF, we investigated whether articular infusions of autologous concentrated adipose tissue are an effective treatment for knee OA patients. METHODS: The knee of 20 OA patients was intra-articularly injected with autologous concentrated adipose tissue, obtained after centrifugation of lipoaspirate. Patients' articular functionality and pain were evaluated by VAS and WOMAC scores at three, six and 18 months from infusion. The osteogenic and chondrogenic ability of ASCs contained in the injected adipose tissue was studied in in vitro primary osteoblast and chondrocyte cell cultures, also plated on 3D-bone scaffold. Knee articular biopsies of patients previously treated with adipose tissue were analyzed. Immunohistochemistry (IHC) and scanning electron microscopy (SEM) were performed to detect cell differentiation and tissue regeneration. RESULTS: The treatment resulted safe, and all patients reported an improvement in terms of pain reduction and increase of function. According to the osteogenic or chondrogenic stimulation, ASCs expressed alkaline phosphatase or aggrecan, respectively. The presence of a layer of newly formed tissue was visualized by IHC staining and SEM. The biopsy of previously treated knee joints showed new tissue formation, starting from the bone side of the osteochondral lesion. CONCLUSIONS: Overall our data indicate that adipose tissue infusion stimulates tissue regeneration and might be considered a safe treatment for knee OA.


Assuntos
Tecido Adiposo/transplante , Transplante de Células-Tronco Mesenquimais , Osteoartrite do Joelho/cirurgia , Tecido Adiposo/citologia , Idoso , Artroscopia , Feminino , Humanos , Injeções Intra-Articulares , Articulação do Joelho/cirurgia , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Pessoa de Meia-Idade , Transplante Autólogo
20.
Int J Oral Maxillofac Implants ; 33(6): 1247-1254, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30427955

RESUMO

PURPOSE: The aim of this vitro study was to reproduce and evaluate the response of bone and bacteria to traditional and innovative implant surfaces with difference wettability. MATERIALS AND METHODS: Two hundred fifty-two samples made of grade 4 titanium with different coating (machined [MAC]; double-etched, Ti-AE; zirconium nitride [Ti-ZrN]) were used for this in vitro study. Disks were divided into test (bioactivated using plasma of argon) and control group (untreated). To assess the surface morphology of the specimens, representative images were acquired via scanning electron microscopy (SEM). Murine preosteoblasts (MC3T3-E1) were used to study the biologic response in vitro, while the quantification of protein adsorption was achieved through the incubation of the titanium samples in a 2% solution of fetal bovine serum (FBS) in phosphate-buffered saline (PBS). The sterilized titanium disks were then colonized by bacterial species from a single sputum sample obtained from a healthy volunteer. For every analysis, 24 disks were used (12 for each group). RESULTS: SEM and topographic analyses demonstrated a Sa value of 0.33 (Ti-ZrN), 0.34 (MAC), and 0.62 (Ti-AE). Compared with the control groups, plasma treatment significantly increased the protein adsorption level on all the different titanium surfaces (5.88 ± 0.21 vs 7.85 ± 0.21, 7.13 ± 0.14 vs 9.74 ± 0.65, 4.41 ± 0.62 vs 6.13 ± 0.52, respectively, for MAC, Ti-treated, and Ti-ZrN). Similar behavior was described for cell adhesion (27.67 ± 2.03 vs 58.00 ± 20.13, 116.67 ± 12.02 vs 159.33 ± 8.09, 52.00 ± 4.73 vs 78.33 ± 4.67, respectively, for MAC, Ti-treated, and Ti-ZrN). Plasma treatment significantly augmented the number of CFU only in MAC and ZrN samples. CONCLUSION: With the limitations of this in vitro study, the following conclusions could be drawn: (1) rough implant surfaces present a higher adhesion and proliferation of preosteoblastic cells and bacterial biofilm; (2) rough implant surfaces benefited the most by the plasma of argon treatment.


Assuntos
Aderência Bacteriana/fisiologia , Biofilmes , Adesão Celular/fisiologia , Proliferação de Células/fisiologia , Implantes Dentários/microbiologia , Osteoblastos/citologia , Zircônio/química , Animais , Contagem de Colônia Microbiana , Humanos , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Molhabilidade
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