scholarly journals Eruption of Bioengineered Teeth: A New Approach Based on A Polycaprolactone Biomembrane

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1315
Author(s):  
Céline Stutz ◽  
François Clauss ◽  
Olivier Huck ◽  
Georg Schulz ◽  
Nadia Benkirane-Jessel ◽  
...  
Keyword(s):  
Optimal Solution ◽  
Test Group ◽  
Titanium Implants ◽  
Recipient Site ◽  
New Approach ◽  
Adult Mice ◽  
Functional Tooth ◽  
Bioengineered Tooth

Obtaining a functional tooth is the ultimate goal of tooth engineering. However, the implantation of bioengineered teeth in the jawbone of adult animals never allows for spontaneous eruption due mainly to ankylosis within the bone crypt. The objective of this study was to develop an innovative approach allowing eruption of implanted bioengineered teeth through the isolation of the germ from the bone crypt using a polycaprolactone membrane (PCL). The germs of the first lower molars were harvested on the 14th day of embryonic development, cultured in vitro, and then implanted in the recipient site drilled in the maxillary bone of adult mice. To prevent the ankylosis of the dental germ, a PCL membrane synthesized by electrospinning was placed between the germ and the bone. After 10 weeks of follow-up, microtomography, and histology of the implantation site were performed. In control mice where germs were directly placed in contact with the bone, a spontaneous eruption of bioengineered teeth was only observed in 3.3% of the cases versus 19.2% in the test group where PCL biomembrane was used as a barrier (p < 0.1). This preliminary study is the first to describe an innovative method allowing the eruption of bioengineered tooth implanted directly in the jawbone of mice. This new approach is a hope for the field of tooth regeneration, especially in children with oligodontia in whom titanium implants are not an optimal solution.

scholarly journals Carbon fiber–reinforced PEEK versus titanium implants: an in vitro comparison of susceptibility artifacts in CT and MR imaging

2020 ◽  
Author(s):  
Theresa Krätzig ◽  
Klaus C. Mende ◽  
Malte Mohme ◽  
Helge Kniep ◽  
Marc Dreimann ◽  
...  
Keyword(s):  
Carbon Fiber ◽  
Vertebral Body ◽  
Titanium Implants ◽  
Fiber Reinforced ◽  
Dose Delivery ◽  
Susceptibility Artifacts ◽  
Carbon Fiber Reinforced ◽  
Radiation Planning

Abstract Artifacts in computed tomography (CT) and magnetic resonance imaging (MRI) due to titanium implants in spine surgery are known to cause difficulties in follow-up imaging, radiation planning, and precise dose delivery in patients with spinal tumors. Carbon fiber–reinforced polyetheretherketon (CFRP) implants aim to reduce these artifacts. Our aim was to analyze susceptibility artifacts of these implants using a standardized in vitro model. Titanium and CFRP screw-rod phantoms were embedded in 3% agarose gel. Phantoms were scanned with Siemens Somatom AS Open and 3.0-T Siemens Skyra scanners. Regions of interest (ROIs) were plotted and analyzed for CT and MRI at clinically relevant localizations. CT voxel–based imaging analysis showed a significant difference of artifact intensity and central overlay between titanium and CFRP phantoms. For the virtual regions of the spinal canal, titanium implants (ti) presented − 30.7 HU vs. 33.4 HU mean for CFRP (p < 0.001), at the posterior margin of the vertebral body 68.9 HU (ti) vs. 59.8 HU (CFRP) (p < 0.001) and at the anterior part of the vertebral body 201.2 HU (ti) vs. 70.4 HU (CFRP) (p < 0.001), respectively. MRI data was only visually interpreted due to the low sample size and lack of an objective measuring system as Hounsfield units in CT. CT imaging of the phantom with typical implant configuration for thoracic stabilization could demonstrate a significant artifact reduction in CFRP implants compared with titanium implants for evaluation of index structures. Radiolucency with less artifacts provides a better interpretation of follow-up imaging, radiation planning, and more precise dose delivery.

A New Approach to Elbow Arthroplasty

1981 ◽  
Vol 10 (2) ◽  
pp. 59-64 ◽  
Author(s):  
W A Souter
Keyword(s):  
Body Weight ◽  
Methyl Methacrylate ◽  
Clinical Results ◽  
Medial Epicondyle ◽  
New Approach ◽  
Articular Surfaces ◽  
Two Component ◽  
And Function

The development of a two component endoprosthesis, the articular surfaces of which are modelled very closely on those of the normal trochlear joint, is described. Fixation is achieved through the use of methyl methacrylate cement around a keel and stem on the ulnar side and around a supracondylar metal stirrup with projecting flanges in the capitellum and medial epicondyle in the humerus. In vitro studies suggest that this fixation should be adequate to resist the forces normally transmitted across the elbow, these forces ranging according to the activity from half to three times body weight. Early clinical results have proved very satisfactory with regard to relief of pain and recovery of flexion, pronation, supination, power and function as a whole. The recovery of lost extension has proved more elusive. A much longer follow-up of two to five years will be required in order to ascertain whether the problem of loosening has been solved.

In Vitro and in Vivo Efficacy of a New Connector Device for Continuous Ambulatory Peritoneal Dialysis

1993 ◽  
Vol 13 (2_suppl) ◽  
pp. 148-151 ◽  
Author(s):  
Giusto Viglino ◽  
Adolfo Colombo ◽  
Paolo Cantu ◽  
Corrado Camerini ◽  
Luigi Catizone ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Continuous Ambulatory Peritoneal Dialysis ◽  
Controlled Trial ◽  
Test Group ◽  
Control Group ◽  
In Vivo Efficacy ◽  
Short Branch

The purpose of this study was to evaluate the In vltro and in vivo efficacy of a new connection system for continuous ambulatory peritoneal dialysis (CAPO), called the T-set. With this system the patient wears a 27–cm extension line filled with Amuchina during the dwell time; the bag is made of a fill container linked to a drainage tube with a Y-shaped set. For bag exchange, only one connection is needed and this is subsequently flushed with the entire drainage volume. The in vitro efficacy of the system was tested with 20 sets filled with 10 mL of Amuchina and inoculated in the distallumen with 2.1x103 colony-forming units (cfu) of S. aureus. After an Incubation of 4–6 hours at 35–37°C, three dialysate samples per set were collected, respectively, at the beginning of drainage and filling. Al1120 samples were negative, whereas two control sets, filled with a phosphate-buffered saline, had positive drainage samples, and at least one positive Infusion sample, Indicating the efficacy of Amuchina in sterilizing the system under conditions simulating touch contamination. To evaluate the in vivo efficacy, safety, and acceptability of the T-system, a prospective randomized controlled trial was performed In seven centers: a control group (CG) of 56 patients (follow-up: 952.3 months, mean±SO: 17.0±7.8) was treated with a long branch (21 patients) or short branch (35 patients) Y-set and a test group (TG) of 66 patients (follow-up: 898.1 months, mean±SO: 13.6±7.8) with the T-set. The two groups were comparable for patient and dialysis characteristics. The incidence of peritonitis was 1143.3 months in the CG and 1129.0 months In the TG (p=NS). The percentage of patients without peritonitis was 67.8% In the CG and 68.2% In the TG (p=NS); the probability of remaining free from peritonitis was, respectively, 76% and 75% In the CG and in the TG at 1 year, and 66% and 60% at 2 years (p=NS). In the CG 26 patients and In the TG 21 patients were already on CAPO before the trial; among these 21 patients, 10 of 10 with the long Y-set and 4 of 11 with the short Y-set who transferred to the T-set preferred the latter for better handling (52.4%) or for less encumbrance (14.3%).

scholarly journals Processing Adipose Tissue to Make it More Stable When Used for Refilling: A Morphologic and Immunohistochemistry Evaluation

2021 ◽  
Vol 58 ◽  
pp. 004695802110610
Author(s):  
Maurizio Sabbatini ◽  
Serena Faruggio ◽  
Giovanni Verna ◽  
Valeria Magnelli ◽  
Francesco Dondero ◽  
...  
Keyword(s):  
Connective Tissue ◽  
Fat Mass ◽  
Immune Cells ◽  
Morphological Changes ◽  
Recipient Site ◽  
Aesthetic Result ◽  
The Aesthetic

Breast reconstruction has gained from lipofilling the possibility to recover the aesthetic outcome of anatomical profile in a more natural appearance. However, until today, the long-term graft survival remains unpredictable, and sometimes it does not guarantee a well-adequate aesthetic result. In the present work, the morphological changes, occurring in fat mass used for refilling, harvested by the Coleman’s procedure or through the washing/fragmenting procedure were analysed. Adipocyte size; immunohistochemistry against CD8, CD31, CD68 and M2-type macrophages and catalase enzyme, were analysed in vitro on fat mass cultured for 4 weeks. Our observation reveals an increase of connective tissue around the mass and a high number of immune cells occurrence in fat mass harvested by the Coleman’s procedure. Instead, the washing/fragmented procedure would reduce the number of immune cells within the fat mass, increase the size of adipocytes, and cause a wider presence of active vessels profile and greater catalase expression. We hypothesize that the fat mass processed by the Coleman’s procedure would remain more reactive due to a higher number of immune and macrophages cells, prone to develop cystic formation, leading to a suboptimal integration in the recipient site. On the other hand, the conditions more prone to realize an optimal integration would occur in the fat mass processed by the washing/fragmenting procedure: a reduced number of immune cells, low amount of connective tissue, presence of larger adipocytes. Follow-up monitoring did support our conclusion, as we observed a reduction of re-intervention for refilling procedure in patients treated with the washing/fragmenting procedure.

A rare case of hypokalaemia and hypophosphataemia secondary to geophagia

2021 ◽  
Vol 14 (5) ◽  
pp. e239322
Author(s):  
Charmaine Schmidt ◽  
Jonathan Oxley Oxland ◽  
Robert Freercks
Keyword(s):  
Creatine Kinase ◽  
Iron Deficiency ◽  
Phosphate Binder ◽  
Rare Case ◽  
Potassium Level ◽  
Serum Potassium Level ◽  
Electrolyte Abnormality ◽  
Distal Muscle

We report a case of severe hypokalaemia and moderate hypophosphataemia from clay ingestion. A 60-year-old woman presented with flaccid paralysis. Investigations revealed a serum potassium level of 1.8 mmol/L, phosphate level of 0.56 mmol/L and creatine kinase level of 30 747 IU/L. She had marked proximal and distal muscle weakness due to severe hypokalaemia and concurrent hypophosphataemia, which likely contributed to the onset of rhabdomyolysis. The patient subsequently admitted to significant pica, most likely secondary to an associated iron deficiency. We conclude that the ingested clay acted as a potassium and phosphate binder. Although we did not investigate the content of the clay in this case, it has been reported that clay can bind potassium in vitro and is rich in minerals such as aluminium that could play a role in the binding of phosphate, although the exact mechanism remains unclear. The patient recovered fully and outpatient follow-up at 6 months and again at 40 months confirmed no electrolyte abnormality, myopathy nor any further geophagia.

scholarly journals Macrophagic Inflammatory Response Next to Dental Implants with Different Macro- and Micro-Structure: An In Vitro Study

2021 ◽  
Vol 11 (12) ◽  
pp. 5324
Author(s):  
Maria Menini ◽  
Francesca Delucchi ◽  
Domenico Baldi ◽  
Francesco Pera ◽  
Francesco Bagnasco ◽  
...  
Keyword(s):  
Inflammatory Response ◽  
Dental Implants ◽  
In Vitro Study ◽  
Titanium Implants ◽  
Implant Surface ◽  
Bone Implant ◽  
Optimal Outcomes ◽  
Negative Controls ◽  
Inflammatory Effect

(1) Background: Intrinsic characteristics of the implant surface and the possible presence of endotoxins may affect the bone–implant interface and cause an inflammatory response. This study aims to evaluate the possible inflammatory response induced in vitro in macrophages in contact with five different commercially available dental implants. (2) Methods: one zirconia implant NobelPearl® (Nobel Biocare) and four titanium implants, Syra® (Sweden & Martina), Prama® (Sweden & Martina), 3iT3® (Biomet 3i) and Shard® (Mech & Human), were evaluated. After 4 h of contact of murine macrophage cells J774a.1 with the implants, the total RNA was extracted, transcribed to cDNA and the gene expression of the macrophages was evaluated by quantitative PCR (qPCR) in relation to the following genes: GAPDH, YWHAZ, IL1β, IL6, TNFα, NOS2, MMP-9, MMP-8 and TIMP3. The results were statistically analyzed and compared with negative controls. (3) Results: No implant triggered a significant inflammatory response in macrophages, although 3iT3 exhibited a slight pro-inflammatory effect compared to other samples. (4) Conclusions: All the samples showed optimal outcomes without any inflammatory stimulus on the examined macrophagic cells.

scholarly journals Age influences susceptibility of brain capillary endothelial cells to La Crosse virus infection and cell death

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Rahul Basu ◽  
Vinod Nair ◽  
Clayton W. Winkler ◽  
Tyson A. Woods ◽  
Iain D. C. Fraser ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Cell Death ◽  
Virus Infection ◽  
La Crosse Virus ◽  
Brain Capillary ◽  
Adult Mice ◽  
Age Related ◽  
Capillary Endothelial Cells ◽  
The Brain

Abstract Background A key factor in the development of viral encephalitis is a virus crossing the blood-brain barrier (BBB). We have previously shown that age-related susceptibility of mice to the La Crosse virus (LACV), the leading cause of pediatric arbovirus encephalitis in the USA, was associated with the ability of the virus to cross the BBB. LACV infection in weanling mice (aged around 3 weeks) results in vascular leakage in the olfactory bulb/tract (OB/OT) region of the brain, which is not observed in adult mice aged > 6–8 weeks. Thus, we studied age-specific differences in the response of brain capillary endothelial cells (BCECs) to LACV infection. Methods To examine mechanisms of LACV-induced BBB breakdown and infection of the CNS, we analyzed BCECs directly isolated from weanling and adult mice as well as established a model where these cells were infected in vitro and cultured for a short period to determine susceptibility to virus infection and cell death. Additionally, we utilized correlative light electron microscopy (CLEM) to examine whether changes in cell morphology and function were also observed in BCECs in vivo. Results BCECs from weanling, but not adult mice, had detectable infection after several days in culture when taken ex vivo from infected mice suggesting that these cells could be infected in vitro. Further analysis of BCECs from uninfected mice, infected in vitro, showed that weanling BCECs were more susceptible to virus infection than adult BCECs, with higher levels of infected cells, released virus as well as cytopathic effects (CPE) and cell death. Although direct LACV infection is not detected in the weanling BCECs, CLEM analysis of brain tissue from weanling mice indicated that LACV infection induced significant cerebrovascular damage which allowed virus-sized particles to enter the brain parenchyma. Conclusions These findings indicate that BCECs isolated from adult and weanling mice have differential viral load, infectivity, and susceptibility to LACV. These age-related differences in susceptibility may strongly influence LACV-induced BBB leakage and neurovascular damage allowing virus invasion of the CNS and the development of neurological disease.

Osseointegrated titanium implants--a new approach in orthodontic treatment

1988 ◽  
Vol 10 (1) ◽  
pp. 98-105 ◽  
Author(s):  
J.  dman ◽  
U. Lekholm ◽  
T. Jemt ◽  
P.-I. Br nemark ◽  
B. Thilander
Keyword(s):  
Orthodontic Treatment ◽  
Titanium Implants ◽  
New Approach

scholarly journals Micro/nano-textured hierarchical titanium topography promotes exosome biogenesis and secretion to improve osseointegration

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Zhengchuan Zhang ◽  
Ruogu Xu ◽  
Yang Yang ◽  
Chaoan Liang ◽  
Xiaolin Yu ◽  
...  
Keyword(s):  
Gene Expression ◽  
Titanium Surface ◽  
Titanium Implants ◽  
Extracellular Secretion ◽  
Exosome Biogenesis ◽  
Marrow Mesenchymal Stem Cells ◽  
Proliferation In Vitro ◽  
Extracellular Environment

Abstract Background Micro/nano-textured hierarchical titanium topography is more bioactive and biomimetic than smooth, micro-textured or nano-textured titanium topographies. Bone marrow mesenchymal stem cells (BMSCs) and exosomes derived from BMSCs play important roles in the osseointegration of titanium implants, but the effects and mechanisms of titanium topography on BMSCs-derived exosome secretion are still unclear. This study determined whether the secretion behavior of exosomes derived from BMSCs is differently affected by different titanium topographies both in vitro and in vivo. Results We found that both micro/nanonet-textured hierarchical titanium topography and micro/nanotube-textured hierarchical titanium topography showed favorable roughness and hydrophilicity. These two micro/nano-textured hierarchical titanium topographies enhanced the spreading areas of BMSCs on the titanium surface with stronger promotion of BMSCs proliferation in vitro. Compared to micro-textured titanium topography, micro/nano-textured hierarchical titanium topography significantly enhanced osseointegration in vivo and promoted BMSCs to synthesize and transport exosomes and then release these exosomes into the extracellular environment both in vitro and in vivo. Moreover, micro/nanonet-textured hierarchical titanium topography promoted exosome secretion by upregulating RAB27B and SMPD3 gene expression and micro/nanotube-textured hierarchical titanium topography promoted exosome secretion due to the strongest enhancement in cell proliferation. Conclusions These findings provide evidence that micro/nano-textured hierarchical titanium topography promotes exosome biogenesis and extracellular secretion for enhanced osseointegration. Our findings also highlight that the optimized titanium topography can increase exosome secretion from BMSCs, which may promote osseointegration of titanium implants.

scholarly journals Single tooth restoration in the maxillary esthetic zone using a one-piece ceramic implant with 1 year of follow-up: case series

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Miren Vilor-Fernández ◽  
Ana-María García-De-La-Fuente ◽  
Xabier Marichalar-Mendia ◽  
Ruth Estefanía-Fresco ◽  
Luis-Antonio Aguirre-Zorzano
Keyword(s):  
Case Series ◽  
Biological Properties ◽  
Titanium Implants ◽  
Plaque Index ◽  
Marginal Bone Loss ◽  
Bleeding On Probing ◽  
Probing Depth ◽  
Zirconia Implants ◽  
Ceramic Implant

Abstract Background Oral implants have helped clinicians to improve the quality of life for many patients. The material of choice for dental implants currently remains titanium type IV, whose mechanical and biological properties have been proven throughout the history of implantology. Yet, this material is not exempt from complications. For these reasons, ceramic alternatives to titanium have emerged. Thus, the purpose of this study is to evaluate peri-implant hard and soft tissue stability with the use of a one-piece ceramic implant (Straumann® PURE Ceramic Implant) during 1 year of follow-up. Study design One-piece all-ceramic zirconia (ZrO2) implants were placed to replace single missing teeth in the esthetic zone. Six to 8 weeks after the procedure, the definitive prosthesis was fabricated. At the time of prosthesis, placement (T0) photographs and periapical radiographs were taken, and the following clinical parameters were recorded: probing depth (PD), plaque index (PI), bleeding on probing (BOP), suppuration on probing (SOP), distance from gingival margin to incisal edge (GM-IE), and Jemt papilla index (JPI). Follow-up appointments were scheduled at 4 (T4), 8 (T8), and 12 (T12) months, when the same parameters were recorded. In addition, plaque control was reinforced and prophylaxis was carried out. In this last appointment, a final periapical radiograph was taken to assess marginal bone loss. Results A total of 32 zirconia implants were placed in 28 patients (16 women and 12 men, aged between 34 and 67 years). The survival and success rate were 96.9%. The increase in probing depth from baseline to 12 months was 0.78 mm. Assessments of plaque index and bleeding on probing showed a slight increase throughout the study. Conclusions The results obtained with the Straumann® PURE Ceramic implants show them to exhibit very good clinical behavior. The survival rate of the implants of our pilot study was 96.9%. For these reasons, we can say that zirconia implants could be an alternative to titanium implants in the esthetic zone.

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