Subperiosteal Anchorage in Orthodontics: A Narrative Review

Orthodontic anchorage is a necessity for every treatment and must be carefully evaluated by the orthodontist. It is defined as the resistance to unwanted dental movement of a tooth or a number of teeth by using different techniques. The purpose of the present paper is to highlight the subperiosteal anchorage applied to orthodontics; this technique has been debated in the literature and the purpose here is to summarize the fields of application. During the first check of previous literature 548 results were found, which have been reduced to 19 selected papers after application of the inclusion criteria and the elimination of duplicates. Multiple electronic databases were searched from 1 January 1995 to 31 December 2020 in order to identify papers eligible for current review. The data obtained by this review underlined the versatility of onplants used as absolute anchorage during orthodontic treatments, the advantages and disadvantages, the biomechanical properties and survival rates, and the clinical procedure. Further clinical studies and research are required to explore other kinds of application and to state specific guidelines; however, this study represents an update and a starting point for clinicians who want to use these devices and for further improvement of the technique.

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Biomechanics of Neutrophil Tethers

Life ◽

10.3390/life11060515 ◽

2021 ◽

Vol 11 (6) ◽

pp. 515

Author(s):

Andrea Cugno ◽

Alex Marki ◽

Klaus Ley

Keyword(s):

Cell Activation ◽

Optical Trap ◽

Biomechanical Properties ◽

Force Microscopy ◽

Advantages And Disadvantages ◽

Atomic Force ◽

Microfluidic Flow ◽

Biomembrane Force Probe ◽

Membrane Reservoir

Leukocytes, including neutrophils, which are propelled by blood flow, can roll on inflamed endothelium using transient bonds between selectins and their ligands, and integrins and their ligands. When such receptor–ligand bonds last long enough, the leukocyte microvilli become extended and eventually form thin, 20 m long tethers. Tether formation can be observed in blood vessels in vivo and in microfluidic flow chambers. Tethers can also be extracted using micropipette aspiration, biomembrane force probe, optical trap, or atomic force microscopy approaches. Here, we review the biomechanical properties of leukocyte tethers as gleaned from such measurements and discuss the advantages and disadvantages of each approach. We also review and discuss viscoelastic models that describe the dependence of tether formation on time, force, rate of loading, and cell activation. We close by emphasizing the need to combine experimental observations with quantitative models and computer simulations to understand how tether formation is affected by membrane tension, membrane reservoir, and interactions of the membrane with the cytoskeleton.

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Biomechanics of insect cuticle: an interdisciplinary experimental challenge

Applied Physics A ◽

10.1007/s00339-021-04439-3 ◽

2021 ◽

Vol 127 (5) ◽

Author(s):

Karen Stamm ◽

Brian Daniel Saltin ◽

Jan-Henning Dirks

Keyword(s):

Meta Analysis ◽

Biomechanical Properties ◽

Measurement Methods ◽

Insect Cuticle ◽

Body Parts ◽

Scientific Methods ◽

Advantages And Disadvantages ◽

Examination Techniques ◽

Evolutionary Success ◽

Experimental Challenge

AbstractThe cuticle exoskeleton plays a key role in facilitating the evolutionary success of insects. Since the mid of the last century, many different biomechanical properties of exoskeletons have been investigated, always utilizing the most sophisticated scientific methods available at the time. So far, information on the biomechanical properties of cuticle seems to be as diverse as the methods used to measure them. As a consequence, insect cuticle is often considered to exhibit the most complex and diverse biomechanical properties of any biological material. However, it remains unclear which role the respective measurement methods and sample treatments used in previous studies play in supporting this claim. This review provides a broad overview of examination techniques used to study biomechanical properties of insect exoskeletons and discusses their respective advantages and disadvantages in describing the properties of a complex material such as cuticle. Our meta-analysis of the present data confirms significant effects of the respective measurement methods, sample treatments and body parts on the obtained mechanical properties. Based on our findings, we highlight research gaps and point out important factors which should be taken into account in future studies on insect cuticle.

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‘More Product, Less Process’ (MPLP): An early printed book project

Journal of Librarianship and Information Science ◽

10.1177/09610006211026739 ◽

2021 ◽

pp. 096100062110267

Author(s):

Karen Attar

Keyword(s):

18Th Century ◽

The United States ◽

Global Changes ◽

Main Research ◽

Advantages And Disadvantages ◽

Main Research Interest ◽

Printed Books ◽

Starting Point ◽

19Th And 20Th Century

This article addresses the challenge to make printed hidden collections known quickly without sacrificing ultimate quality. It takes as its starting point the archival mantra ‘More product, less process’ and explores its application to printed books, mindful of projects in the United States to catalogue 19th- and 20th-century printed books quickly and cheaply with the help of OCLC. A problem is lack of time or managerial inclination ever to return to ‘quick and dirty’ imports. This article is a case study concerning a collection of 18th-century English imprints, the Graveley Parish Library, at Senate House Library, University of London. Faced with the need to provide metadata as quickly as possible for digitisation purposes, Senate House Library decided, in contrast to its normal treatment of early printed books, to download records from the English Short Title Catalogue and amend them only very minimally before releasing them for public view, and to do this work from catalogue cards rather than the books themselves. The article describes the Graveley Parish collection, the project method’s rationale, and the advantages and disadvantages of sourcing the English Short Title Catalogue for metadata. It discusses the drawbacks of retrospective conversion (cataloguing from cards, not books): insufficient detail in some cases to identify the relevant book, and ignorance of the copy-specific elements of books which can constitute the main research interest. The method is compared against cataloguing similar books from photocopies of title pages, and retrospective conversion using English Short Title Catalogue is compared against retrospective conversion of early printed Continental books from cards using Library Hub Discover or OCLC. The control groups show our method’s effectiveness. The project succeeded by producing records fast that fulfilled their immediate purpose and simultaneously would obviously require revisiting. The uniform nature of the collection enabled the saving of time through global changes.

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Sampling Efficacy and Survival Rates of Labarrus pseudolividus (Coleoptera: Scarabaeidae) and Onthophagus taurus (Coleoptera: Scarabaeidae) Using Flotation and Sieve-Separation Methodology

Journal of Insect Science ◽

10.1093/jisesa/ieaa083 ◽

2020 ◽

Vol 20 (6) ◽

Author(s):

Fallon Fowler ◽

Tashiana Wilcox ◽

Stephanie Orr ◽

Wes Watson

Keyword(s):

Habitat Restoration ◽

Survival Rates ◽

Dung Beetles ◽

Light Traps ◽

Safety Issues ◽

Advantages And Disadvantages ◽

Onthophagus Taurus ◽

Baited Traps ◽

Laboratory Colony ◽

Sampling Efficacy

Abstract Understanding collection methodologies and their limitations are essential when targeting specific arthropods for use in habitat restoration, conservation, laboratory colony formation, or when holistically representing local populations using ecological surveys. For dung beetles, the most popular collection methodology is baited traps, followed by light traps and unbaited flight-intercept traps during diversity surveys. A less common collection method, flotation, is assumed to be laborious and messy, and so only a handful of papers exist on its refinement and strengths. Our purpose was threefold: First, we tested the recovery and survival rates of Labarrus (=Aphodius) pseudolividus (Balthasar) and Onthophagus taurus (Schreber) when floating beetle-seeded dung pats to determine potential collection and safety issues. We collected 72.4 and 78% of the seeded L. pseudolividus and O. taurus, respectively, with >95% survival rating. Second, we developed a flotation-sieving technique that enables users to rapidly collect and passively sort dung beetles with less time and effort. Specifically, we often collected 50–100 g of wild dung beetles within a couple of hours of gathering dung and sorted them in a couple more by allowing dung beetles to sort themselves by size within a series of sieves; Third, we reviewed flotation-based advantages and disadvantages in comparison to other methodologies.

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Activation of Cilia-Independent Hedgehog/GLI1 Signaling as a Novel Concept for Neuroblastoma Therapy

Cancers ◽

10.3390/cancers13081908 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1908

Author(s):

Anke Koeniger ◽

Anna Brichkina ◽

Iris Nee ◽

Lukas Dempwolff ◽

Anna Hupfer ◽

...

Keyword(s):

Hedgehog Signaling ◽

Primary Cilia ◽

Survival Rates ◽

Genetic Alterations ◽

Novel Therapy ◽

Therapeutic Concept ◽

Pathway Activation ◽

Starting Point ◽

Novel Concept ◽

Neural Crest Differentiation

Although being rare in absolute numbers, neuroblastoma (NB) represents the most frequent solid tumor in infants and young children. Therapy options and prognosis are comparably good for NB patients except for the high risk stage 4 class. Particularly in adolescent patients with certain genetic alterations, 5-year survival rates can drop below 30%, necessitating the development of novel therapy approaches. The developmentally important Hedgehog (Hh) pathway is involved in neural crest differentiation, the cell type being causal in the etiology of NB. However, and in contrast to its function in some other cancer types, Hedgehog signaling and its transcription factor GLI1 exert tumor-suppressive functions in NB, rendering GLI1 an interesting new candidate for anti-NB therapy. Unfortunately, the therapeutic concept of pharmacological Hh/GLI1 pathway activation is difficult to implement as NB cells have lost primary cilia, essential organelles for Hh perception and activation. In order to bypass this bottleneck, we have identified a GLI1-activating small molecule which stimulates endogenous GLI1 production without the need for upstream Hh pathway elements such as Smoothened or primary cilia. This isoxazole compound potently abrogates NB cell proliferation and might serve as a starting point for the development of a novel class of NB-suppressive molecules.

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Revision Rates After Total Ankle Replacement: A Comparison of Clinical Studies and Arthroplasty Registers

Foot & Ankle International ◽

10.1177/10711007211053862 ◽

2021 ◽

pp. 107110072110538

Author(s):

Georg Hauer ◽

Reinhard Hofer ◽

Markus Kessler ◽

Jan Lewis ◽

Lukas Leitner ◽

...

Keyword(s):

Clinical Studies ◽

Revision Rate ◽

Mobile Bearing ◽

Total Ankle Replacement ◽

Second Step ◽

Fixed Bearing ◽

Inclusion Criteria ◽

Level Of Evidence ◽

Ankle Replacement ◽

Significant Difference

Background: The aim of this study was to assess the outcome of total ankle replacement (TAR) regarding revision rates by comparing clinical studies of the last decade to data displayed in arthroplasty registers. The secondary aim was to evaluate whether dependent clinical studies show a superior outcome to independent publications. Additionally, revision rates of mobile bearing implants (MB-TARs) were compared to those of fixed bearing implants (FB-TARs). Methods: Clinical studies on TARs between 2010 and 2020 were systematically reviewed, with the endpoint being a revision for any reason. The parameter “revision rate per 100 observed component years (CYs)” was calculated for each publication. The pooled revision rate for clinical studies was compared to the data reported in arthroplasty registers. In a second step, revision rates were subdivided and analyzed for independent and dependent publications and for FB-TARs and MB-TARs. Results: A total of 43 publications met the inclusion criteria comprising 5806 TARs. A revision rate of 1.8 per 100 observed CYs was calculated, corresponding to a 7-year revision rate of 12.6%. The 3 arthroplasty registers included showed revision rates ranging from 8.2% to 12.3% after 7 years. No significant difference between dependent and independent publications nor between FB-TARs and MB-TARs was detected. Conclusion: Revision rates of clinical studies and arthroplasty registers are comparable. Surgeons can compare their own revision rates with those from this study. Dependent studies do not seem to be biased, and no superiority for one bearing type can be described. Level of Evidence: Level III, systematic review of level III studies

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Advanced Hydrogels for Cartilage Tissue Engineering: Recent Progress and Future Directions

Polymers ◽

10.3390/polym13234199 ◽

2021 ◽

Vol 13 (23) ◽

pp. 4199

Author(s):

Mahshid Hafezi ◽

Saied Nouri Khorasani ◽

Mohadeseh Zare ◽

Rasoul Esmaeely Neisiany ◽

Pooya Davoodi

Keyword(s):

Tissue Engineering ◽

Cartilage Tissue Engineering ◽

Cartilage Regeneration ◽

Biomechanical Properties ◽

Tissue Growth ◽

Cartilage Tissue ◽

Self Healing ◽

Advantages And Disadvantages ◽

Wide Range

Cartilage is a tension- and load-bearing tissue and has a limited capacity for intrinsic self-healing. While microfracture and arthroplasty are the conventional methods for cartilage repair, these methods are unable to completely heal the damaged tissue. The need to overcome the restrictions of these therapies for cartilage regeneration has expanded the field of cartilage tissue engineering (CTE), in which novel engineering and biological approaches are introduced to accelerate the development of new biomimetic cartilage to replace the injured tissue. Until now, a wide range of hydrogels and cell sources have been employed for CTE to either recapitulate microenvironmental cues during a new tissue growth or to compel the recovery of cartilaginous structures via manipulating biochemical and biomechanical properties of the original tissue. Towards modifying current cartilage treatments, advanced hydrogels have been designed and synthesized in recent years to improve network crosslinking and self-recovery of implanted scaffolds after damage in vivo. This review focused on the recent advances in CTE, especially self-healing hydrogels. The article firstly presents the cartilage tissue, its defects, and treatments. Subsequently, introduces CTE and summarizes the polymeric hydrogels and their advances. Furthermore, characterizations, the advantages, and disadvantages of advanced hydrogels such as multi-materials, IPNs, nanomaterials, and supramolecular are discussed. Afterward, the self-healing hydrogels in CTE, mechanisms, and the physical and chemical methods for the synthesis of such hydrogels for improving the reformation of CTE are introduced. The article then briefly describes the fabrication methods in CTE. Finally, this review presents a conclusion of prevalent challenges and future outlooks for self-healing hydrogels in CTE applications.

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DENTAL IMPLANTS IN MEDICALLY COMPROMISED PATIENTS

10.36106/ijar/6912181 ◽

2021 ◽

pp. 64-65

Author(s):

A.Bhagya Mathivanan ◽

Balakrishnan Balakrishnan

Keyword(s):

Literature Review ◽

Dental Implants ◽

Clinical Studies ◽

Meta Analysis ◽

Endocrine Disorders ◽

Oral Bisphosphonates ◽

Inclusion Criteria ◽

Vital Function ◽

The Status ◽

Compromised Patients

The present study was carried out with an aim and interest to evaluate the status of implant, its function, and durability which are placed in the medically compromised patient .The literature review was done in order to identify the medically compromised patients with implants and were on medication with oral bisphosphonates for the ossication to be formed around dental implants for its vital function. The articles published between the years2001 to 2010 were included in the study. The articles of clinical studies in which 7-8 patients were treated, consensus articles,review articles and meta analysis were included. The total of 34 articles was found in which 26 articles met the inclusion criteria. The systematic diseases/ medically compromised are those patients with cardiac, diabetic,endocrine disorders and who are also seems to treated with dental implant and its outcomes.

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Dual-Mobility Cups in Primary Total Hip Arthroplasty

Zeitschrift für Orthopädie und Unfallchirurgie ◽

10.1055/a-1527-7758 ◽

2021 ◽

Author(s):

Petri Bellova ◽

Jens Goronzy ◽

Roman Riedel ◽

Tim Grothe ◽

Albrecht Hartmann ◽

...

Keyword(s):

Hip Arthroplasty ◽

Neuromuscular Disorders ◽

Survival Rates ◽

High Survival ◽

Dual Mobility ◽

Advantages And Disadvantages ◽

Large Head ◽

Dual Mobility Cups ◽

Primary Hip Arthroplasty

AbstractDual-mobility cups (DMCs) were introduced in France more than 40 years ago and are increasingly used not only in hip revision but also primary hip arthroplasty. Due to a simulated large-head articulation and increased jumping distance, DMCs can contribute to a high range of motion in the hip joint and reduce the risk of instability. Numerous studies have reported low dislocation rates and high survival rates in the mid-term follow-up. Nevertheless, long-term data, especially on primary hip replacement, remain limited, and the effect of recent designs and material innovations is still unclear. Therefore, primary DMCs are mainly proposed in patients at high risk for dislocation (i.e. pelvitrochanteric insufficiency, compromised spinopelvic mobility, neuromuscular disorders, obesity and femoral neck fractures). Based on a review of recently published studies referring to these indications, the current study discusses the advantages and disadvantages of DMCs.

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Coadjuvant Anti-VEGF A Therapy Improves Survival in Patients with Colorectal Cancer with Liver Metastasis: A Systematic Review

Gastrointestinal Disorders ◽

10.3390/gidisord2020007 ◽

2020 ◽

Vol 2 (2) ◽

pp. 71-85

Author(s):

Isabel Novo ◽

Bárbara Campos ◽

Filipa Pinto-Ribeiro ◽

Sandra F. Martins

Keyword(s):

Colorectal Cancer ◽

Overall Survival ◽

Liver Metastasis ◽

Survival Rates ◽

Progression Free Survival ◽

Vascular Endothelial ◽

Inclusion Criteria ◽

Effective Treatment Modality ◽

Endothelial Growth Factor ◽

The Impact

Background: the presence of liver metastasis in colorectal cancer (CRC) remains one of the most significant prognostic factors. Objective: systematically review the results of studies evaluating the benefit of adding bevacizumab to a normal chemotherapy regime in the survival of patients with colorectal-cancer liver metastasis (CRLM). Search methods: Pubmed and Google Scholar databases were searched for eligible articles (from inception up to the 2 April 2019). Inclusion criteria: studies including patients with CRLM receiving anti-vascular endothelial growth factor (VEGF; bevacizumab) as treatment, overall survival as an outcome; regarding language restrictions, only articles in English were accepted. Main results: Eleven studies met the inclusion criteria. In 73% of these cases, chemotherapy with bevacizumab was an effective treatment modality for treating CRLM, and its administration significantly extended both overall survival (OS) and/or progression-free survival (PFS). Nevertheless, three articles showed no influence on survival rates of bevacizumab-associated chemotherapy. Author conclusions: It is necessary to standardize methodologies that aim to evaluate the impact of bevacizumab administration on the survival of patients with CRLM. Furthermore, follow-up time and the cause of a patient’s death should be recorded, specified, and cleared in order to better calculate the survival rate and provide a comparison between the produced literature.

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