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1.
J Mater Sci Mater Med ; 35(1): 9, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38285196

RESUMO

The reconstruction of bony defects in the alveolar crest poses challenges in dental practice. Guided tissue regeneration (GTR) and guided bone regeneration (GBR) procedures utilize barriers to promote bone regeneration and prevent epithelial growth. This study focuses on evaluating the antibacterial properties of marine algae-polylactic acid (PLA) composite membranes compared to commercially available collagen membranes. Marine algae (Corallina elongata, Galaxaura oblongata, Cystoseira compressa, Saragassum vulgare, and Stypopodium schimperi) were processed into powders and blended with PLA to fabricate composite membranes. Cytocompatibility assays using human periodontal ligament fibroblasts (n = 3) were performed to evaluate biocompatibility. Antibacterial effects were assessed through colony-forming units (CFU) and scanning electron microscopy (SEM) analysis of bacterial colonization on the membranes. The cytocompatibility assays demonstrated suitable biocompatibility of all marine algae-PLA composite membranes with human periodontal ligament fibroblasts. Antibacterial assessment revealed that Sargassum vulgare-PLA membranes exhibited the highest resistance to bacterial colonization, followed by Galaxaura oblongata-PLA and Cystoseira compressa-PLA membranes. SEM analysis confirmed these findings and revealed smooth surface textures for the marine algae-PLA membranes compared to the fibrous and porous structures of collagen membranes. Marine algae-PLA composite membranes show promising antibacterial properties and cytocompatibility for guided bone and tissue regeneration applications. Sargassum vulgare-PLA membranes demonstrated the highest resistance against bacterial colonization. These findings suggest that marine algae-PLA composite membranes could serve as effective biomaterials for infection control and tissue regeneration. Further in vivo validation and investigation of biodegradation properties are necessary to explore their clinical potential.


Assuntos
Colágeno , Poliésteres , Humanos , Processo Alveolar , Antibacterianos/farmacologia
2.
J Craniomaxillofac Surg ; 52(1): 127-135, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38129185

RESUMO

The study aimed to analyze bone regeneration in critical-size defects using hybrid scaffolds biomechanically adapted to the specific defect and adding the growth factor rhBMP-2. For this animal study, ten minipigs underwent bilateral defects in the corpus mandibulae and were subsequently treated with novel cylindrical hybrid scaffolds. These scaffolds were designed digitally to suit the biomechanical requirements of the mandibular defect, utilizing finite element analysis. The scaffolds comprised zirconium dioxide-tricalcium phosphate (ZrO2-TCP) support struts and TCP foam ceramics. One scaffold in each animal was loaded with rhBMP-2 (100 µg/cm³), while the other served as an unloaded negative control. Fluorescent dyes were administered every 2 weeks, and computed tomography (CT) scans were conducted every 4 weeks. Euthanasia was performed after 3 months, and samples were collected for examination using micro-CT and histological evaluation of both hard and soft tissue. Intravital CT examinations revealed minor changes in radiographic density from 4 to 12 weeks postoperatively. In the group treated with rhBMP-2, radiographic density shifted from 2513 ± 128 (mean ± SD) to 2606 ± 115 Hounsfield units (HU), while the group without rhBMP-2 showed a change from 2430 ± 131 to 2601 ± 67 HU. Prior to implantation, the radiological density of samples measured 1508 ± 30 mg HA/cm³, whereas post-mortem densities were 1346 ± 71 mg HA/cm³ in the rhBMP-2 group and 1282 ± 91 mg HA/cm³ in the control group (p = 0.045), as indicated by micro-CT measurements. The histological assessment demonstrated successful ossification in all specimens. The newly formed bone area proportion was significantly greater in the rhBMP-2 group (48 ± 10%) compared with the control group without rhBMP-2 (42 ± 9%, p = 0.03). The mean area proportion of remaining TCP foam was 23 ± 8% with rhBMP-2 and 24 ± 10% without rhBMP-2. Successful bone regeneration was accomplished by implanting hybrid scaffolds into critical-size mandibular defects. Loading these scaffolds with rhBMP-2 led to enhanced bone regeneration and a uniform distribution of new bone formation within the hybrid scaffolds. Further studies are required to determine the adaptability of hybrid scaffolds for larger and potentially segmental defects in the maxillofacial region.


Assuntos
Implantes Dentários , Suínos , Animais , Porco Miniatura , Regeneração Óssea , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Mandíbula/patologia , Proteína Morfogenética Óssea 2/uso terapêutico , Osteogênese , Fator de Crescimento Transformador beta/uso terapêutico , Alicerces Teciduais , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Fosfatos de Cálcio
3.
J Robot Surg ; 17(6): 2861-2867, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37803127

RESUMO

The aim of the current study was to test the technical and clinical feasibility of a robotic system and investigate its potential in the surgical repair of perforated Schneiderian membranes using an ex-vivo porcine model. Eight pig heads were operated conventionally via a surgical loop and eight pig heads with the surgical robot "Symani® Surgical System" (Medical Microinstruments, Inc., Pisa, Italy). On each specimen, the Schneiderian membrane was incised over a length of 0.7 mm resembling a perforation. Operation time, the maximum sinusoidal pressure, the course of the pressure and the filling volume were measured. Additionally, adaptation of the wound edges has been detected via scanning electron microscopy. There were no significant differences for the pressure maximum (p = 0.528), for the time until the pressure maximum was reached (p = 0.528), or for the maximum filling volume (p = 0.674). The time needed for the suturing of the membrane via robotic surgery was significantly longer (p < 0.001). However, the scanning electron microscope revealed a better adaptation of the wound edges with robotic surgery. The technical feasibility of robot-assisted suturing of Schneiderian membrane laceration using the robotic system has been confirmed for the first time. No differences considering the pressure resistance compared to the conventional repair could be observed, but advantages in wound adaptation could be found with an electron microscope. Regarding the material and training costs and limited indications spectrum, robotic surgery systems still might not present financially feasible options in the daily dental practice yet.


Assuntos
Procedimentos Cirúrgicos Robóticos , Humanos , Animais , Suínos , Procedimentos Cirúrgicos Robóticos/métodos , Estudos de Viabilidade , Complicações Intraoperatórias , Mucosa Nasal , Itália
4.
Curr Issues Mol Biol ; 45(8): 6927-6940, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37623256

RESUMO

Successful treatment for any type of carcinoma largely depends on understanding the patterns of invasion and migration. For oral squamous cell carcinoma (OSCC), these processes are not entirely understood as of now. Invadopodia and podosomes, called invadosomes, play an important role in cancer cell invasion and migration. Previous research has established that cortactin (CTTN) is a major inducer of invadosome formation. However, less is known about the expression patterns of CTTN and other genes related to it or invadopodia formation in OSCC during tumor progression in particular. In this study, gene expression patterns of CTTN and various genes (n = 36) associated with invadopodia formation were analyzed to reveal relevant expression patterns and give a comprehensive overview of them. The genes were analyzed from a whole genome dataset of 83 OSCC samples relating to tumor size, grading, lymph node status, and UICC (Union for Internatioanl Cancer Control). The data revealed significant overexpression of 18 genes, most notably CTTN, SRC (SRC proto-onocogene, non-receptor tyrosine kinase), EGFR (epidermal growth factor receptor), SYK (spleen associated tyrosine kinase), WASL (WASP like actin nucleation promotion factor), and ARPC2 (arrestin beta 1) due to their significant correlation with further tumor parameters. This study is one of the first to summarize the expression patterns of CTTN and related genes in a complex group of OSCC samples.

5.
J Funct Biomater ; 14(7)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37504867

RESUMO

Background cold atmospheric plasma (CAP) is known to be a surface-friendly yet antimicrobial and activating process for surfaces such as titanium. The aim of the present study was to describe the decontaminating effects of CAP on contaminated collagen membranes and their influence on the properties of this biomaterial in vitro. Material and Methods: A total of n = 18 Bio-Gide® (Geistlich Biomaterials, Baden-Baden, Germany) membranes were examined. The intervention group was divided as follows: n = 6 membranes were treated for one minute, and n = 6 membranes were treated for five minutes with CAP using kINPen® MED (neoplas tools GmbH, Greifswald, Germany) with an output of 5 W, respectively. A non-CAP-treated group (n = 6) served as the control. The topographic alterations were evaluated via X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Afterward, the samples were contaminated with E. faecalis for 6 days, and colony-forming unit (CFU) counts and additional SEM analyses were performed. The CFUs increased with CAP treatment time in our analyses, but SEM showed that the surface of the membranes was essentially free from bacteria. However, the deeper layers showed remaining microbial conglomerates. Furthermore, we showed, via XPS analysis, that increasing the CAP time significantly enhances the carbon (carbonyl group) concentration, which also correlates negatively with the decontaminating effects of CAP. Conclusions: Reactive carbonyl groups offer a potential mechanism for inhibiting the growth of E. faecalis on collagen membranes after cold atmospheric plasma treatment.

6.
Int J Implant Dent ; 8(1): 34, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36063250

RESUMO

BACKGROUND: The objective of the current study was to assess the clinical and radiological outcomes following autologous grafting from the iliac crest treated with autologous stem cells in-situ to reduce the postoperative bone graft resorption rate. MATERIALS AND METHODS: The study group consisted of patients who underwent vertical augmentation of the jaws via bone grafts harvested from the iliac crest enriched with bone-marrow aspirate concentrates (stem cell group). The first control group (control) included 40 patients underwent a vertical augmentation with autologous bone grafts from the iliac crest. In the second control group, 40 patients received identical surgical procedure, whereas the autologous bone graft was covered with a thin layer of deproteinized bovine bone matrix and a collagen membrane (DBBM group). Clinical complications, implant survival, radiological assessment of the stability of the vertical height and histological evaluation at the recipient site have been followed up for 24 months postoperatively. RESULTS: No differences in terms of implant survival were observed in the groups. In the stem cell group, the resorption after 4-6 months was 1.2 ± 1.3 mm and significantly lower than the resorption of the control group with 1.9 ± 1.6 mm (P = 0.029) (DBBM group: 1.4 ± 1.2 mm). After 12 months, the resorption of the stem cell group was 2.1 ± 1.6 mm and significantly lower compared to the control group (4.2 ± 3.0 mm, P = 0.001) and DBBM group (resorption 2.7 ± 0.9 mm, P = 0.012). The resorption rate in the second year was lower compared to the first year and was measured as 2.7 ± 1.7 mm in the stem cell group (1-year bone loss in the time period of 12-24 months of 0.6 mm compared to 2.1 mm in the first 12 months). The resorption was significantly lower compared to the control group (4.7 ± 2.9 mm; P = 0.003, DBBM group: 3.1 ± 0.5 mm, P = 0.075). CONCLUSIONS: Autologous bone-marrow aspirate concentrate could enhance the dimensional stability of the bone grafts and improve the clinical standard of complex reconstruction of the alveolar ridge. Even though the intraoperative cell enrichment requires an additional equipment and technical specification, it represents an alternative method for in-situ regeneration by osteogenic induction with a contribution of a manageable cost factor.


Assuntos
Aumento do Rebordo Alveolar , Reabsorção Óssea , Processo Alveolar , Aumento do Rebordo Alveolar/métodos , Animais , Medula Óssea , Transplante Ósseo/métodos , Bovinos , Humanos , Ílio/cirurgia
7.
J Mater Sci Mater Med ; 33(2): 13, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35061114

RESUMO

Nickel-titanium (NiTi) belongs to the group of shape-memory alloys (SMAs), which are characterized by flexibility and reversible deformability. Advanced techniques in 3D printing by selective laser-melting (SLM) process allow the manufacturing of complex patient-specific implants from SMAs. Osteosynthesis materials made of NiTi could be used for minimally invasive surgical approaches in oral- and maxillofacial surgery. However, the in vivo biocompatibility has not yet been fully investigated, especially in load-sharing and load-bearing implants. The aim of this study was to evaluate the in vivo biocompatibility of SLM-produced NiTi for intraosseous and subperiosteal applications. Test specimens were implanted into the frontonasal bone of ten miniature pigs. To assess peri-implant bone metabolism, fluorescent dye was administered after 2, 4, 6, 10, 12, and 14 weeks intraperitoneally. Specimens and the surrounding tissues were harvested after 8 and 16 weeks for histological analysis. While the NiTi implants presented a higher bone-to-implant contact ratio (BIC) after 8 than after 16 weeks (43.3 vs. 40.3%), the titanium implants had a significantly higher BIC after 16 weeks (33.6 vs. 67.7%). Histologically, no signs of peri-implant inflammation or foreign-body reaction were detectable. With respect to this preliminary study design, 3D-printed NiTi shows sufficient biocompatibility for intraosseous and subperiosteal implant placement.


Assuntos
Lasers , Níquel/efeitos adversos , Próteses e Implantes , Titânio/efeitos adversos , Animais , Materiais Biocompatíveis , Osso e Ossos , Teste de Materiais , Suínos , Porco Miniatura
8.
J Craniomaxillofac Surg ; 50(1): 70-75, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34620537

RESUMO

The objective of the current study is to retrospectively evaluate cycling related dental and maxillofacial injuries and to gain insight into the epidemiology and results of these accidents. Data of patients who were admitted due to the maxillofacial injuries between April 2018 and September 2020 were retrospectively evaluated regarding the patients' characteristics, helmet wearing, type of radiological assessment required for diagnosis and therapy, injury patterns, duration of hospitalization and concomitant injuries. Data of 162 patients were included. 86 (53.08%) patients presented with at least one maxillofacial fracture. A total of 186 maxillofacial bones were fractured. Zygomatico-maxillary complex was the most commonly affected region (n:103, 55,36%). Analysis of the dental traumata revealed that crown fracture without pulp exposure was the most commonly observed entity (n:37, 32.46%) and upper central incisors (n:61, 53.50%) were the most commonly affected teeth. The overall ratio of the number of the fracture line/fracture case was 2.80. However, this ratio was statistically higher in e-bike cases (4.25) compared to non-e-bike riders (2.34) (p:0.014). Bicycle related maxillofacial injuries could correlate with specific morbidity rates and result in severe injuries of the maxillofacial region.


Assuntos
Traumatismos Maxilofaciais , Traumatismos Dentários , Acidentes de Trânsito , Ciclismo , Dispositivos de Proteção da Cabeça , Humanos , Traumatismos Maxilofaciais/epidemiologia , Traumatismos Maxilofaciais/etiologia , Estudos Retrospectivos
9.
Polymers (Basel) ; 13(6)2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33801946

RESUMO

Biodegradable collagen-based materials have been preferred as scaffolds and grafts for diverse clinical applications in density and orthopedy. Besides the advantages of using such bio-originated materials, the use of collagen matrices increases the risk of infection transmission through the cells or the tissues of the graft/scaffold. In addition, such collagen-based solutions are not counted as economically feasible approaches due to their high production cost. In recent years, incorporation of marine algae in synthetic polymers has been considered as an alternative method for preparation grafts/scaffolds since they represent abundant and cheap source of potential biopolymers. Current work aims to propose a novel composite patch prepared by blending Sargassum vulgare powders (SVP) to polylactide (PLA) as an alternative to the porcine-derived membranes. SVP-PLA composite patches were produced by using a modified solvent casting method. Following detailed material characterization to assess the cytocompatibility, human osteoblasts (HOBs) and osteosarcoma cells (SaOS-2) were seeded on neat PLA and SVP-PLA patches. MTT and BrdU assays indicated a greater cytocompatibility and higher proliferation for HOBs cultured on SVP-PLA composite than for those cultured on neat PLA. SaOS-2 cells cultured on SVP-PLA exhibited a significant decrease in cell proliferation. The composite patch described herein exhibits an antiproliferative effect against SaOS-2 cells without impairing HOBs' adhesion and proliferation.

10.
Int J Implant Dent ; 7(1): 45, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33928447

RESUMO

BACKGROUND: The aim of the study is to evaluate the accuracy of a new implant navigation system on two different digital workflows. METHODS: A total of 18 phantom jaws consisting of hard and non-warping plastic and resembling edentulous jaws were used to stimulate a clinical circumstance. A conventional pilot-drill guide was conducted by a technician, and a master model was set by using this laboratory-produced guide. After cone beam computed tomography (CBCT) and 3D scanning of the master models, two different digital workflows (marker tray in CBCT and 3D-printed tray) were performed based on the Digital Imaging Communication in Medicine files and standard tessellation language files. Eight Straumann implants (4.1 mm × 10 mm) were placed in each model, six models for each group, resulting in 144 implant placements in total. Postoperative CBCT were taken, and deviations at the entry point and apex as well as angular deviations were measured compared to the master model. RESULTS: The mean total deviations at the implant entry point for MTC (marker tray in CBCT), 3dPT (3d-printed tray), and PDG (pilot-drill guide) were 1.024 ± 0.446 mm, 1.027 ± 0.455 mm, and 1.009 ± 0.415 mm, respectively, and the mean total deviations at the implant apex were 1.026 ± 0.383 mm, 1.116 ± 0.530 mm, and 1.068 ± 0.384 mm. The angular deviation for the MTC group was 2.22 ± 1.54°. The 3dPT group revealed an angular deviation of 1.95 ± 1.35°, whereas the PDG group showed a mean angular deviation of 2.67 ± 1.58°. Although there were no significant differences among the three groups (P > 0.05), the navigation groups showed lesser angular deviations compared to the pilot-drill-guide (PDG) group. Implants in the 3D-printed tray navigation group showed higher deviations at both entry point and apex. CONCLUSIONS: The accuracy of the evaluated navigation system was similar with the accuracy of a pilot-drill guide. Accuracy of both preoperative workflows (marker tray in CBCT or 3D-printed tray) was reliable for clinical use.


Assuntos
Cirurgia Assistida por Computador , Desenho Assistido por Computador , Tomografia Computadorizada de Feixe Cônico , Imageamento Tridimensional , Fluxo de Trabalho
11.
J Craniomaxillofac Surg ; 49(8): 726-731, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33676818

RESUMO

The aim of this animal study was to investigate the effect of platelet-rich plasma (PRP) injections into the temporomandibular joint (TMJ) to treat antigen-induced arthritis AIA. AIA was induced via the application of bovine serum albumin (BSA) into the TMJ. Clear histological signs and protein analysis results indicating inflammation of the TMJ were observed. Afterwards, two PRP injections were performed over an interval of 2 weeks. Concentration levels of the proinflammatory cytokines IL-1ß (PRP: 33.7 ± 5.6 pg/mg, untreated: 50.0 ± 2.9 pg/mg; p = 0.04) and TNF-α (PRP: 20.7 ± 2.5 pg/mg, untreated: 31.4 ± 2.7 pg/mg; p = 0.03) were significantly decreased in the PRP-treated joints. A significant reduction in signs of histological inflammation, such as hyperplasia of the synovial membrane, leucocyte infiltration, cartilage surface alterations, and an increase in cartilage-specific glycosaminoglycan content, was observed. This animal study supports the understanding of the underlying effects of PRP treatment in the TMJ, and may enhance novel PRP therapies in the future.


Assuntos
Artrite , Cartilagem Articular , Plasma Rico em Plaquetas , Animais , Injeções Intra-Articulares , Sus scrofa , Suínos , Articulação Temporomandibular
12.
J Craniomaxillofac Surg ; 49(3): 191-195, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33454184

RESUMO

The aim of the study was to assess the surgical outcomes following venous anastomosis with a coupling device and hand-sewn anastomosis in the reconstruction of the maxillofacial region. The study sample was recruited from patients who underwent reconstructive surgeries between January 2011 and November 2016. Tumor type, recipient veins, distribution of flap type, flap survival rates and anastomosis associated complications requiring a flap revision were documented. The follow-up period was four years. In total, 236 patients were included in this study, in which 201 reconstructions were performed via microsurgical venous coupling device (82.04%), whereas hand sewn anastomosis was used in 44 patients (17.96%). Postoperative complications regarding the anastomosis technique revealed that venous coupler devices showed significantly lower complications (4,97%) compared to hand sewn anastomosis (11,36%) (p < 0.05). Within the limitations of the current study, it can be concluded that the coupler system does appear to have advantages over conventional hand-sewn venous anastomosis and should be preferred when possible.


Assuntos
Retalhos de Tecido Biológico , Procedimentos de Cirurgia Plástica , Anastomose Cirúrgica/efeitos adversos , Humanos , Microcirurgia , Estudos Retrospectivos , Resultado do Tratamento
13.
Cancers (Basel) ; 12(12)2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33327621

RESUMO

Most available cancer chemotherapies are based on systemically administered small organic molecules, and only a tiny fraction of the drug reaches the disease site. The approach causes significant side effects and limits the outcome of the therapy. Targeted drug delivery provides an alternative to improve the situation. However, due to the poor release characteristics of the delivery systems, limitations remain. This report presents a new approach to address the challenges using two fundamentally different mechanisms to trigger the release from the liposomal carrier. We use an endogenous disease marker, an enzyme, combined with an externally applied magnetic field, to open the delivery system at the correct time only in the disease site. This site-activated release system is a novel two-switch nanomachine that can be regulated by a cell stress-induced enzyme at the cellular level and be remotely controlled using an applied magnetic field. We tested the concept using sphingomyelin-containing liposomes encapsulated with indocyanine green, fluorescent marker, or the anticancer drug cisplatin. We engineered the liposomes by adding paramagnetic beads to act as a receiver of outside magnetic energy. The developed multifunctional liposomes were characterized in vitro in leakage studies and cell internalization studies. The release system was further studied in vivo in imaging and therapy trials using a squamous cell carcinoma tumor in the mouse as a disease model. In vitro studies showed an increased release of loaded material when stress-related enzyme and magnetic field was applied to the carrier liposomes. The theranostic liposomes were found in tumors, and the improved therapeutic effect was shown in the survival studies.

14.
IET Nanobiotechnol ; 14(7): 584-589, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33010133

RESUMO

The objective of the current in-vitro study was to evaluate the biocompatibility of a new type of CAD/CAM scaffold for bone tissue engineering by using human cells. Porous lightweight titanium scaffolds and Bio-Oss® scaffolds as well as their eluates were used for incubation with human osteoblasts, fibroblasts and osteosarcoma cells. The cell viability was assessed by using fluorescein diazo-acetate propidium iodide staining. Cell proliferation and metabolism was examined by using MTT-, WST-Test and BrdU-ELISA tests. Scanning electron microscope was used for investigation of the cell adhesion behaviour. The number of devitalised cells in all treatment groups did not significantly deviate from the control group. According to MTT and WST results, the number of metabolically active cells was decreased by the eluates of both test groups with a more pronounced impact of the eluate from Bio-Oss®. The proliferation of the cells was inhibited by the addition of the eluates. Both scaffolds showed a partial surface coverage after 1 week and an extensive to complete coverage after 3 weeks. The CAD/CAM titanium scaffolds showed favourable biocompatibility compared to Bio-Oss® scaffolds in vitro. The opportunity of a defect-specific design and rapid prototyping by selective laser melting are relevant advantages in the field of bone tissue engineering and regenerative medicine.


Assuntos
Materiais Biocompatíveis/química , Desenho Assistido por Computador , Engenharia Tecidual/instrumentação , Engenharia Tecidual/métodos , Alicerces Teciduais , Titânio/química , Reabsorção Óssea , Osso e Ossos , Adesão Celular , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Fibroblastos/metabolismo , Humanos , Técnicas In Vitro , Lasers , Teste de Materiais , Microscopia Eletrônica de Varredura , Osteoblastos/metabolismo , Osteossarcoma/metabolismo , Porosidade , Medicina Regenerativa , Sais de Tetrazólio/química , Tiazóis/química
15.
J Craniofac Surg ; 31(6): e560-e563, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32516214

RESUMO

Recently, a technical note describing a promising method for the management of infections after sinus bone grafting by irrigating the corresponding area with hydrogen peroxide based solution with an aid of a drain has been published. The aim of this paper was to present the histological and radiological results of the above mentioned technique. A total of 17 patients who have presented with infections secondary to sinus bone grafting enrolled in the study. During implant placement, bone was collected from the originally grafted site with a trephine burr for radiological examination via micro-computed tomography and histological examination. According to the results of the current study, Bio-Oss acted as a scaffold, and mature fibrous bone formed trabeculae, which assembled to an interlinked trabecular structure. Average results obtained from the microradiography confirmed the higher percentage of Bio-Oss (27.21% ±â€Š3.31%) at the corresponding area; whereas the amount of newly formed bone was slightly lower (6.79% ±â€Š1.13%) As a conclusion, this simple and minimally invasive technique might be beneficial in avoiding removal of bone graft material and could help in rescuing the former laborious procedure.


Assuntos
Transplante Ósseo , Implantação Dentária Endóssea/métodos , Seio Maxilar/cirurgia , Idoso , Substitutos Ósseos , Transplante Ósseo/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Minerais , Microtomografia por Raio-X
16.
Curr Pharm Des ; 26(31): 3828-3833, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32188378

RESUMO

BACKGROUND: Nanoparticle imaging and tracking the release of the loaded material from the nanoparticle system have attracted significant attention in recent years. If the release of the loaded molecules could be monitored reliably in vivo, it would speed up the development of drug delivery systems remarkably. METHODS: Here, we test a system that uses indocyanine green (ICG) as a fluorescent agent for studying release kinetics in vitro and in vivo from the lipid iron nanoparticle delivery system. The ICG spectral properties like its concentration dependence, sensitivity and the fluctuation of the absorption and emission wavelengths can be utilized for gathering information about the change of the ICG surrounding. RESULTS: We have found that the absorption, fluorescence, and photoacoustic spectra of ICG in lipid iron nanoparticles differ from the spectra of ICG in pure water and plasma. We followed the ICG containing liposomal nanoparticle uptake into squamous carcinoma cells (SCC) by fluorescence microscopy and the in vivo uptake into SCC tumors in an orthotopic xenograft nude mouse model under a surgical microscope. CONCLUSION: Absorption and emission properties of ICG in the different solvent environment, like in plasma and human serum albumin, differ from those in aqueous solution. Photoacoustic spectral imaging confirmed a peak shift towards longer wavelengths and an intensity increase of ICG when bound to the lipids. The SCC cells showed that the ICG containing liposomes bind to the cell surface but are not internalized in the SCC-9 cells after 60 minutes of incubation. We also showed here that ICG containing liposomal nanoparticles can be traced under a surgical camera in vivo in orthotopic SCC xenografts in mice.


Assuntos
Verde de Indocianina , Nanopartículas , Animais , Lipossomos , Camundongos , Imagem Óptica , Análise Espectral
17.
Odontology ; 108(1): 133-142, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31278484

RESUMO

The objective of the current study was to demonstrate the 6-year clinical and radiological treatment outcomes of the technique performed by immediately loading of three implants (single straight in the mid-line and two tilted distal implants) for the management of total edentulous mandibles and introduce a simple decision matrix for selection of the most appropriate protocol in cases with insufficient length of the interforaminal area. Re-assessments were performed over a total observation period of 6 years after surgery via measurement of bone resorption around implants, bleeding on probing, plaque accumulation, periodontal probing depth, bite force measurements and oral health impact profile. A total of 29 patients (45% women and 55% men) with a mean age of 65 ± 6 years enrolled in the study. 14 patients received an acryl-based bridge as definitive prosthetic restoration and 15 patients received a ceramic-based restoration. Both during the immediate loading phase and during the 6-year follow-up, there was no implantation loss. Regardless of the implant position, all implants showed continuous bone loss over the observation time. The bone loss around dental implants during observation period was only maximum 1.0 ± 1 mm and it remained well within the limits for 'success' according to the 2007 Pisa consensus (< 2 mm). The plaque index showed no significant fluctuations between the implant positions and the individual examination times. The approach described herein might help the surgeon by avoiding unnecessary loss of bone strength, selecting implant sites, and establishing the biomechanical advantage of increased A-P spread for immediate function.


Assuntos
Perda do Osso Alveolar , Implantes Dentários , Carga Imediata em Implante Dentário , Arcada Edêntula , Idoso , Implantação Dentária Endóssea , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Feminino , Seguimentos , Humanos , Masculino , Mandíbula , Pessoa de Meia-Idade , Resultado do Tratamento
18.
Med Hypotheses ; 135: 109482, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31739080

RESUMO

Current paper aims to hypothesize that, oral surgical interventions such as tooth extractions, endosseous implant placement, subgingival curettage, etc. might result in widespread of fungal species via blood stream and can cause fungal contaminations of the cardiac valves. We hereby suggest that, an additional fungal endocarditis risk assessment and prevention protocol should be created for patients with a possible risk of endocarditis development.


Assuntos
Endocardite/etiologia , Micoses/etiologia , Procedimentos Cirúrgicos Bucais/efeitos adversos , Cirurgia Bucal/métodos , Endocardite/microbiologia , Doenças das Valvas Cardíacas/cirurgia , Valvas Cardíacas/microbiologia , Humanos , Micoses/microbiologia , Medição de Risco
19.
J Craniomaxillofac Surg ; 47(4): 661-667, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30846326

RESUMO

BACKGROUND: Promoting the directional attachment of gingiva to the dental implant leads to the formation of tight connective tissue which acts as a seal against the penetration of oral bacteria. Such a directional growth is mostly governed by the surface texture. MATERIAL AND METHODS: In this study, three different methods, mechanical structuring, chemical etching and laser treatment, have been explored for their applicability in promoting cellular attachment and alignment of human primary gingival fibroblasts (HGFIBs). RESULTS: The effectiveness of mechanical structuring was shown as a simple and a cost-effective method to create patterns to align HGIFIBs. CONCLUSION: Combining mechanical structuring with chemical etching enhanced both cellular attachment and the cellular alignment.


Assuntos
Implantes Dentários , Adesão Celular , Fibroblastos , Gengiva , Humanos , Propriedades de Superfície , Titânio
20.
J Craniomaxillofac Surg ; 47(6): 932-939, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30910433

RESUMO

Rheumatoid arthritis (RA) is a chronic inflammatory disease and the temporomandibular joint (TMJ) is affected in up to 50%, resulting in pain, limited mouth opening and dental malocclusion. The outcome of conservative and surgical therapies is unsatisfying in many cases. The purpose of this study was to establish a large animal model of antigen-induced arthritis (AIA) of the TMJ that enables the investigation of the pathogenesis of RA and the evaluation of new therapies. In five domestic pigs, systemic immunization was performed via consecutive intramuscular injections of bovine serum albumin (BSA). Then, AIA was induced via the application of BSA into the TMJ. Injection with saline served as the control. After ten weeks, the joints and adjacent tissues were harvested for histological analysis and cytokine quantification. The changes observed in the AIA specimens included severe synovial inflammation, cartilage-specific glycosaminoglycan content loss, and cartilage surface and discus alterations as well as the formation of chondrocyte clusters. Protein analyses of the synovia showed enhanced levels of IL-1ß, IL-6, TNFα and VEGF. A porcine model of immunologic arthritis of the TMJ was successfully established. This model may be used in future studies to investigate the underlying pathogenesis of RA and new therapeutic strategies.


Assuntos
Cartilagem Articular , Transtornos da Articulação Temporomandibular , Animais , Soroalbumina Bovina , Sus scrofa , Suínos , Articulação Temporomandibular , Transtornos da Articulação Temporomandibular/veterinária
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