bluuebunny/crossref_metadata_2025 huggingface dataset:
Evolution of the geological structure and mechanical properties due to the collision of multiple basement topographic highs in a forearc accretionary wedge: Insights from numerical simulations
Authors: Miyakawa Ayumu , Noda Atsushi , Koge Hiroaki
Published: September 2021

We propose a conceptual geological model for the collision of multiple basement topographic highs (BTHs; e.g., seamounts, ridges, and horsts) with a forearc accretionary wedge. Even though there are many BTHs on an oceanic plate, there are few examples of modeling the collision of multiple BTHs. We conducted numerical simulations using the discrete element method to examine the effects of three BTH collisions with forearcs. The typical geological structure associated with a BTH collision was reproduced during the collision of the first BTH, and multiple BTH collisions create a cycle of formation of BTH collisional structures. Each BTH forces the basal décollement to move up to the roof décollement, and the roof décollement becomes inactive after the passage of the BTH, and then the décollement moves down to the base. As the active décollement position changes, the sequences of underthrust sediments and uplifted imbricate thrusts are sandwiched between the décollements and incorporated into the wedge. At a low horizontal compressive stress, a “shadow zone” is formed behind (i.e., seaward of) the BTH. When the next BTH collides, the horizontal compressive stress increases and tectonic compaction progresses, which reduce the porosity in the underthrust sediments. Heterogeneous evolution of the geological and porosity structure can generate a distinctive pore pressure pattern. The underthrust sediments retain fluid in the “shadow” of the BTH. Under the strong horizontal compressive stresses associated with the next BTH collision, pore pressure increases along with a rapid reduction of porosity in the underthrust sediments. The distinctive structural features observed in our model are comparable to the large faults in the Kumano transect of the Nankai Trough, Japan, where a splay fault branches from the plate boundary and there are old and active décollements. A low-velocity and high-pore-pressure zone are located at the bottom of the accretionary wedge and in front (i.e., landward) of the subducting ridge in the Kumano transect. This suggests that strong horizontal compressive stresses associated with the current BTH collision has increased the pore pressure within the underthrust sediments associated with previous BTHs.
Resveratrol Nanocrystal Loaded Orodispersible Films: Formulation Development and In Vitro Characterization
Authors: Ozdemir Samet , Uner Burcu , Karakucuk Alptug
Published: September 2021

Nanocrystals are a feasible system to improve the aqueous solubility of poorly soluble compounds. Orodispersible films (ODFs) offer a rapid release of the drug in the mouth and are preferred for patients with dysphagia or paediatrics. The objective of the current study was to develop resveratrol (RES) nanocrystal-loaded ODFs. RES nanocrystals were prepared by antisolvent precipitation in the existence of Poloxamer 188 as a polymeric stabilizer. Polyvinyl alcohol was used for the preparation of the ODFs by using the solvent casting method. Then, RES nanocrystals were incorporated into the films. Particle size (PS), polydispersity index (PDI), and zeta potential (ZP) values were measured for nanocrystals. ODFs were characterized, and bioadhesion, disintegration, and in vitro release studies were performed. RES nanocrystals were obtained with 631 nm PS, 0.314 PDI and − 14.3 ZP values. Over 90% of RES nanocrystals were loaded in ODFs, which were approximately 75 µm in thickness. The thermal and crystal properties of nanocrystals in ODFs were preserved regarding DSC and FTIR analyses. Homogenous distribution in smooth films was observed on SEM. Mechanical properties and bioadhesion forces were found to be appropriate for ODFs. The disintegration time was found below 30 seconds for nanocrystal loaded films. RES nanocrystal loaded film formulations showed > 85% release in 5 minutes, significantly higher (p < 0.05) than those prepared with coarse RES. Novel RES nanocrystal-loaded ODFs can be a promising delivery system for use as an antioxidant with improved patient compliance by increasing solubility and physical stability of RES.
Prevalence and Associated Factors of Early Initiation of Complementary Feeding among Infants in Hawassa City, Southern Ethiopia
Authors: Bekele Fekadu , Meshesha Berhan , Eshetu Bethlehem
Published: September 2021

Background: Nutrition in infancy and early childhood is a critical determinant of health outcomes and productivity of the individual throughout his/her life years. Thus, World Health Organization and United Nations Children’s Fund recommend initiation of complementary foods at 6 months to ensure optimal child growth and development. In Ethiopia, compliance with infant and young child feeding recommendations is low despite its adoption of different international policies and guidelines. Thus, the aim of this study was to assess the magnitude and associated factors of early initiation of complementary feeding among infants in Hawassa City, Southern Ethiopia, 2021. Methods: A community-based cross-sectional study was conducted in Hawassa City, in January 2021. A systematic random sampling technique was applied to recruit 543 mothers who had infants aged 6 to 12 months. A structured and interviewer-administered questionnaire was used to collect data. by six. A multivariable logistic regression analysis was applied to identify factors associated with the early initiation of complementary feeding. Adjusted odds ratio with corresponding 95% confidence interval was calculated to show the strength of association. Result: A total of 543 mothers/caregivers of infants were interviewed face to face, giving a response rate of 97%. Approximately 38% of mothers initiated complementary foods before six months of age. After adjusting for confounders, maternal employment status [AOR (95%CI): 4.72 (2.84, 7.87)] and postnatal care checkup [AOR (95%CI): 1.92 (1.24, 2.97)] were significantly associated with early initiation of complementary feeding. Conclusion: A high proportion of mothers initiated complementary feeding before six months of infant's age. Postnatal care checkup and mother’s occupational status were significantly associated with early initiation of complementary feeding. Thus, increasing the coverage of postnatal care utilization and creating mother-friendly workplaces for breastfeeding mothers is of paramount importance to realize appropriate complementary feeding practices.
A Simple and Effective Method to Improve Pinnacle Auto-planning Based on Rectal Cancer
Authors: Hua Lei , Chen Gang , Xiao Han , Pan Xiangou , Zhang JianYing
Published: September 2021

Background: Try to re-optimize the results of pinnacle Auto-planning (AP) and explore the feasibility of obtaining more dosiologically advantageous AP plans by reducing "experience-based optimization parameters". Methods: 35 rectal cancer cases with preoperative radiotherapy were selected and all plans are designed retrospectively with Pinnacle9.1 AP. Firstly we take the doctor's clinical prescription as a universal optimization parameters, get the first reference group CP; secondly we set the results of manual plans (MP) which were already used for clinical treatments as the optimization parameters, replacing the physicist's initial experience, get the second reference group IE; at last we reduce the results of MP by 15% as the optimization parameters , get the control group T. By keeping the other optimization conditions unchanged, we designed AP plans for all three groups. Wilcoxon rank sum tests were performed for CP-T and IE-T based on the dosiological parameters of the planning target volume(PTV) and organs at risk(OARs). Results: Dose distribution of all three groups was in a clinically acceptable range. The dose of OARs in T group was significantly lower than CP and IE,the differences were statistically significant. Conclusion: Experience-based AP plan has a space for re-optimization, and appropriately reducing the results of MP as optimization parameters is a simple and feasible way.
Quantum sensing for gravitational cartography
Authors: Stray* Ben , Lamb* Andrew , Kaushik Aisha , Vovrosh Jamie , Rodgers Anthony , Winch Jonathan , Hayati Farzad , Boddice Daniel , Stabrawa Artur , Niggebaum Alexander , Langlois Mehdi , Lien Yu-Hung , Lellouch Samuel , Roshanmanesh Sanaz , Ridley Kevin , de Villiers Geoffrey , Brown Gareth , Cross Trevor , Tuckwell George , Faramarzi Asaad , Metje Nicole , Bongs Kai , Holynski Michael
Published: September 2021

The sensing of gravity has emerged as an important tool in geophysics for applications such as engineering and climate research 1,2,3 where it provides the capability to probe otherwise inaccessible features under the surface of the Earth. Examples include the monitoring of temporal variations such as those found in aquifers4 and geodesy5. However, resolving metre scale underground features is rendered impractical by the long measurement times needed for the removal of vibrational noise6. Here, we overcome this limitation and open up the field of gravity cartography by realising a practical quantum gravity gradient sensor. Our design suppresses the effects of micro-seismic and laser noise, as well as thermal and magnetic field variations, and instrument tilt. The instrument achieves an uncertainty of 20 E (1 E = 10-9 s-2) and is used to perform a 0.5 m spatial resolution survey across a 8.5 m long line, detecting a 2 m tunnel with a signal to noise ratio of 8. The tunnel centre is localised using a Bayesian inference method, determining the centre to within ± 0.19 m in the horizontal direction and finding the centre depth as (1.89 -0.59/+2.3) m. The removal of vibrational noise enables improvements in instrument performance to directly translate into reduced measurement time in mapping. This opens new applications such as mapping the water distribution of aquifers and evaluating impacts on the water table7, detecting new features in archaeology8,9,10,11, determination of soil properties12 and water content13, and reducing the risk of unforeseen ground conditions in the construction of critical energy, transport and utilities infrastructure14, providing a new window into the underground.
A novel radiographic grid aiming device for percutaneous renal puncture
Authors: Xu Guibin
Published: September 2021

Background

This in-vitro study aims to assess the efficacy of a novel radiographic grid aiming device as compared to the conventional “bull’s eye” puncture technique for percutaneous renal puncture.
Methods

This new device uses two radiopaque rings for targeting, somewhat similar to the concept of gun sights. The device is designed to improve the ease and accuracy of the “bull’s eye” puncture technique. We compared this device to the conventional “bull’s eye” puncture technique using a porcine kidney inside a chicken carcass as the study model. Two first-year residents used both the radiographic grid aiming device in turn, Group A, and the conventional bull’s eye technique, Group B, to perform punctures to reach the target porcine calyces in order. Related data were recorded and analyzed.
Results

23 renal calyceal punctures were performed per group. There were no statistical differences in the overall puncture success rate, puncture time, or radiation exposure time and dose between the two groups. The number of punctures required to achieve success was higher in group B and the distance between the puncture site to the center of papillary fornix was shorter in group A, all P < 0.05.
Conclusions

The novel radiographic grid aiming device showed no advantage in the overall success rate for renal puncture. However, it offered the advantages of more precise puncture with fewer puncture attempts. It may serve as a useful tool for training. It may also offer some benefit to surgeons who are novices at percutaneous renal puncture.
Ibrutinib plus obinutuzumab as frontline therapy for chronic lymphocytic leukemia is associated with a lower rate of infusion-related reactions and with sustained remissions after ibrutinib discontinuation: a single-arm, open-label, phase 1b/2 clinical trial NCT0231576
Authors: Castro Januario E. , Lengerke-Diaz Paula A. , Velez-Lujan Juliana , Choi Michale Y. , Moreno-Cortes Eider F. , Forero Jose V. , Garcia-Robledo Juan Esteban , Jacobs Chaja , McCarthy Colin , Heinen Alaina , Amaya-Chanaga Carlos I. , Kipps Thomas J.
Published: September 2021

Ibrutinib-based therapies are costly and require continuous administration. We hypothesized combining BTK inhibition with anti-CD20 monoclonal antibodies would yield deep remissions allowing discontinuation. We enrolled 32 therapy-naïve CLL patients to receive ibrutinib plus obinutuzumab, followed by single-agent ibrutinib. Patients could discontinue ibrutinib after 36 months with sustained complete response (CR). We evaluated treatment safety, efficacy, and outcomes after ibrutinib discontinuation. The overall response rate was 100%, 28% achieved a CR, and 12.5% achieved bone marrow undetectable minimal residual disease. At a three-year median follow-up, 91% remain in remission with 100% overall survival. Five patients in sustained CR stopped ibrutinib and have not progressed. Eight non-CR patients discontinued for other reasons, with only two progressing. The treatment was safe, with a lower IRR rate. All patients responded to treatment with longer time-to-progression after discontinuation of ibrutinib. Our data support the evaluation of ibrutinib discontinuation strategies in more extensive clinical trials.
Characterization of the mitochondrial Huso huso genome with new aspects into its organization with presence of tandem repeat in the 12SrRNA and tRNA-Glu
Authors: Dadkhah Khadijeh , Mianji Ghodrat Rahimi , barzegar Ali , Farhadi Ayoub
Published: September 2021

The sturgeon group is an economically important group in the world due to the production of caviar, and they are also a suitable old species for researching on the evolution of the mitochondrial genome. In H.huso sequencing, we identified a distinct genome organization relative to other species that has never been reported before. In this specie, the mitochondrial genome consisted of 13 genes encoding proteins, 22tRNA and 2rRNA, and two non-coding regions that followed other vertebrates. In addition, H.huso had an pseudo tRNA-Glu between ND6 and Cytb and also had a 52-nucleotide tandem repeat with two replications in the 12SrRNA. This duplication event is related to the slipped strand during replication, which can remain in the strand as a result of mispairing during replication. Furthermore, an 82 bp repeat sequence with three replications was observed in the D-loop control region, which is usually visible in different species. Regulatory elements are also visible in the control region of the mitochondrial genome that include termination sequences and conserved regulatory blocks. Genomic compounds showed the highest conservation in terms of rRNA and tRNA, while protein-encoded genes and non-encoded regions had the highest divergence. The mitochondrial genome was phylogenetically assayed using 13 protein-encoding genes.
Sentiment Analysis Using Treebank Filtered Preprocess with Relevant Vector Boost Classifier
Authors: P.Rajendiran Rajendiran , Priyadarsini P.L.K.
Published: September 2021

The procedure of identifying and classifying opinions in a piece of text to find out whether customer reviews towards a particular product or service are positive, negative, or neutral is termed as sentiment analysis. Stock market prediction is one of the most attractive topics in academic and real-life business. Many data mining techniques about sentiment analysis are suffering from the inaccuracy of prediction. The low classification accuracy has a direct effect on the reliability of stock market indicators. Treebank filtering Data Preprocessing based Ochiai-Barkman Relevance Vector Linear Programming Boost Classification (TFDP-ORVLPBC) technique is used for stock market prediction using sentimental analysis with higher prediction accuracy and lesser classification time for enhancing accuracy of stock market based on product review. Initially, the customer reviews and feedback on services or products are collected from the large database. After that, the collected customer reviews are preprocessed by performing the process such as tokenization, stemming, filtering. In order to achieve sentimental analysis through classifying customer reviews as positive and negative, Ochiai-Barkman Relevance Vector Linear Programming Boost Classification algorithm is used. The Linear Programming Boost Classification algorithm constructs with an empty set of weak classifiers as the Ochiai-Barkman Relevance Vector machine. The customer reviews are classified based on the Ochiai-Barkman similarity coefficient. The ensemble technique combines the weak classification results into strong by minimizing the error. In this way, the classification performance gets improved and the prediction of the stock market is carried out in a more accurate manner. Experimental evaluation is carried out on factors such as prediction accuracy, sensitivity, specificity, and prediction time versus amount of customer reviews.
A Hydraulic Soft Microhand with an Application of Live Insect Manipulation
Authors: Kordmahale Sina Baghbani , Qu Jian , Muliana Anastasia Hanifah , Kameoka Jun
Published: September 2021

We have developed micro scale hydraulic/pneumatic soft grippers and demonstrated the handling of an insect. These grippers are built on Polydimethylsiloxane (PDMS) with the soft material casting technique to form three finger-like columns, which are placed on a circular membrane. The fingers have a length of 1.5mm/2mm and a diameter of 300µm each; the distance between two fingers is 600µm of center-to-center distance. Membrane is built as a 150µm soft skin on the top of a cylindrical void. Applying a pressure difference between the interior of the void and the exterior can bend the membrane. Bending the membrane causes the motion of opening/closing of the gripper, and as a result, the three fingers can grip an object or release it. The PDMS was characterized and the experimental results were used later in Abaqus software to simulate the gripping motion. The produced force and range of deformation of the grippers were investigated by simulation and experiment. The results of the simulation agrees with the experiments. The maximum 543 µN force was measured for the microfluidic compatible microgrippers.Using this microhand gripper, the an ant was manipulated successfully without any damage. Results showed fabricated devices have great potential as a micro/bio manipulator.
Blackleg in cattle in the Irkutsk region
Authors: Blokhin Andrei A. , Toropova Nadezhda N. , Burova Olga A. , Zakharova Olga I.
Published: September 2021

Blackleg is an acute, toxic, infectious, non-contagious disease of domestic and wild ruminants that occurs while the animals are pastured. This article describes an outbreak of blackleg on a farm in Siberia (Russia). This article provides a detailed description of these cases based on the results of comprehensive diagnostic and epidemiological investigations. The distinctive features (in addition to the characteristic features) were as follows: the outbreak of the disease occurred in early spring when there was abundant snow cover; the disease appeared in both vaccinated and unvaccinated cattle; the characteristic clinical signs were low-grade fever, the absence of crepitus, and the presence of haematomas containing erythrocytes with basophilic granularity. The evidence suggests that blackleg can present with a variety of conditions and symptoms in cattle.
Domination for subordinated positive semigroups
Authors: Chen-Yu Li
Published: September 2021

We first give a necessary and sufficient condition for -f(B) to be dominated by -f(A), where f is a completely Bernstein function, B and A are C0-semigroup generators. Then we prove that there is no domination relationship between a semigroup and the subordinated semigroup if additional conditions are satisfied.
Identification of hub-genes, lncRNAs, and skin cancer inducer genes through meta-analysis of Hidradenitis Suppurativa disease transcriptome data.
Authors: Shahbazi Mehrdad , Ziaei Nikta
Published: September 2021

This research is aimed to explore the molecular response of the skin cells to Hidradenitis Suppurativa (HS). Microarray transcriptome data for patients with HS, merged and employed to identify the differentially expressed genes (DEGs), gene ontology (GO), and long non-coding RNAs (lncRNAs). A protein-protein interaction network, and consequently, a co-expression network, was constructed for the essential genes. The key genes' clinical relevance was also established by survival analysis, relative expression level, immunohistochemistry, and immune infiltration correlation analysis. Finally, potential herbal ingredients with inhibitory effects on cancer inducer proteins were characterized using the Traditional Chinese Medicine (TCMD) database. The chemokine signaling pathway was the gene ontology of the most significant cluster found by clusterONE. Myocardial Infarction Associated Transcript (MIAT) and RNA Polymerase II Subunit J4, Pseudogene (POLR2J4) are the predicted lncRNAs for up-and down-regulated genes. Interleukin 6 (IL6), Formyl Peptide Receptor 2 (FPR2), C-X-C Motif Chemokine Ligand 10 (CXCL10), C-C Motif Chemokine Receptor 7 (CCR7), and C-C Motif Chemokine Ligand 5 (CCL5) genes were predicted as hub-genes. Tryptophan 2,3-Dioxygenase (TDO2), Serpin Family B Member 4 (SERPINB4), and Matrix Metallopeptidase 3 (MMP3) were demonstrated to be potential cancer inducers due to their high expression level in HS disease. These genes also were positively correlated with dendritic cells, T cell CD4+, monocytes, and neutrophils in the skin cancer microenvironment. Piceatannol, Salicylic acid, and magnolol herbal ingredients were predicted as potential compounds with inhibitory effects on SERPIN B4, MMP3, and TDO2, respectively. The output of the present study will aid in a better understanding of the HS disease and consequent cancer induction mechanism.
Use of the pass-through method to solve sound radiation problems of a spherical electro-elastic source of zero order
Authors: Korzhyk Oleksii , Naida Sergey , Kurdiuk Sergii , Nizhynska Valeriia , Korzhyk Maxim , Naida Anton
Published: September 2021

In the article was solved the problem of radiation of a sound by the electroacoustic transducer which is executed in the form of a thin spherical cover, using a pass-through method. The outer and inner surfaces of the shell are completely electroded.

The application of this method provides an opportunity to avoid inaccuracies that arise during the traditional formulation of boundary conditions for acoustic mechanical fields, the use of equivalent substitution schemes and the absence of boundary conditions for the electric field in general. Given methodology eliminates these shortcomings by applying conjugation conditions, taking into account the types of electroding of the surfaces of piezoceramic transducers, the introduction of boundary conditions for current and voltage. The results of the solution demonstrate the high capabilities of this pass-through method, in terms of taking into account the peculiarities of determining the characteristics of these fields, values and dependences of the main complex characteristics of the electroelastic transducer, and auxiliary material constants of the piezoelectric material.

The proposed approach is relevant, because it allows to increase the reliability of modeling the operating conditions of acoustic transducers in the context of wave problems of acoustics. Aim is to enhance the range of performances and build algorithms solving problems of stationary mode hydroelectroelasticity sound radiation. The expected results are presented in terms of improving approaches to studying the features of the oscillatory process of the active elements of sound-emitting systems and the accompanying effects of the transformation of interconnected fields involved in the formation of the acoustic signal in the liquid
Study on model for cutting force when milling SCM440 steel
Authors: Thien Nguyen Van , Trung Do Duc
Published: September 2021

This article presents empirical study results when milling SCM440 steel. The cutting insert to be used was a TiN coated cutting insert with tool tip radius of 0.5 mm. Experimental process was carried out with 18 experiments according to Box-Behnken matrix, in which cutting speed, feed rate and cutting depth were selected as the input parameters of each experiment. In addition, cutting force was selected as the output parameter. Analysis of experimental results has determined the influence of the input parameters as well as the interaction between them on the output parameters. From the experimental results, a regression model showing the relationship between cutting force and input parameters was built. Box-Cox and Johnson data transformations were applied to construct two other models of cutting force. These three regression models were used to predict cutting force and compare with experimental results. Using parameters including coefficient of determination (R-Sq), adjusted coefficient of determination (R-Sq(adj)) and percentage mean absolute error (% MAE) between the results predicted by the models and the experimental results are the criteria to compare the accuracy of the cutting force models. The results have determined that the two models using two data transformations have higher accuracy than model not using two data transformations. A comparison of the model using the Box-Cox transformation and the model using the Johnson transformation was made with a t-test. The results confirmed that these two models have equal accuracy. Finally, the development direction for the next study is mentioned in this article
Fully guided placement of orthodontic miniscrews— a technical report
Authors: Kirnbauer Barbara , Rugani Petra , Santigli Elisabeth , Tepesch Philipp , Ali Kamran , Jakse Norbert
Published: September 2021

Introduction

Orthodontic miniscrews are used to obtain skeletal anchorage during orthodontic treatment and their application is growing due to the simple method of placement and removal, which invites improved patient compliance without significant impact on function and aesthetics. However, complications and risks are reported that underscore the need for a thorough preoperative assessment to enable accurate placement, especially in confined sites. A novel approach is presented which employs a custom-designed 3D-printed splint to facilitate a fully-guided placement of orthodontic miniscrews.

Materials and methods

The presented splint was virtually planned using coDiagnostiX® software after matching the DICOM data and STL file, to enable fully-guided screw insertion. Insertion depth was defined by a sleeve tube height that provided a depth stop when contact was reached with the head of the hand piece. Additionally, to prevent movement of the insertion instrument, a custom metallic sleeve was designed and 3D-printed by a metallic printer.

Results

Accurate placement was achieved and no complications were experienced during insertion and use.

Conclusions

The insertion approach provides more predictable results and enables accurate placement of orthodontic screws. The procedure avoids associated risks and complications primarily encountered in difficult cases.
Effectiveness of different psychological interventions in reducing fixed orthodontic pain: A systematic review and meta-analysis
Authors: Feng Chong , Wu Chenzhou , Jiang Zhaowei , Zhang Linkun , Zhang Xizhong
Published: September 2021

Background/Objective

Pain induced by tooth movement is a common experience for orthodontic patients. The effectiveness of psychological intervention, as a new approach to control pain, has not been fully explored. Hence, this systematic review and meta-analysis is intended to evaluate the analgesic effect of psychological intervention within the week after fixed orthodontic initial arch wire placement.

Methods

A computerised literature search was conducted in the Medline (1966-2019), Embase (1984-2019), Cochrane Library (Issue 1 of 2019), CBMdisk (1978-2019) and CNKI (1994-2019) databases to identify randomised clinical trials (RCTs), which used psychological interventions to relieve pain during fixed orthodontic treatment. Specific inclusion and exclusion criteria were applied to identify relevant articles. The data were extracted independently by two reviewers and a quality assessment was carried out by using the Cochrane Collaboration ‘risk of bias’ tool. Meta-analyses were conducted with fixed or random effects models as appropriate. Statistical heterogeneity was also examined. The RevMan 5.3 software was used for data analysis.

Results

A total of 472 articles were identified, from which nine RCTs were finally included. A meta-analysis revealed that after initial arch wire placement, cognitive behaviour therapy (CBT) and music therapy could significantly reduce pain within three days compared with a control group. In addition, there were no differences in pain reduction between CBT and music therapy within one week. Furthermore, a structured phone and text follow-up could significantly reduce and control pain and had the same effectiveness in pain reduction.

Conclusions

In the short term after initial arch wire placement, all psychological interventions could significantly reduce the intensity of pain without adverse effects. In the current study, there was no significant difference in pain relief between the different psychological interventions. In the future, more high-quality research with consistency in research design is needed for further evaluation.
Congenitally absent maxillary lateral incisors. A case report illustrating the use of a Mesialslider and a customised lingual appliance
Authors: Pies Stephan , Wilmes Benedict , Vasudavan Sivabalan
Published: September 2021

Background

A young adolescent female, aged 17 years and one month, presented seeking orthodontic treatment to address the congenital absence of her maxillary lateral incisors.

Aims

The therapeutic aims were to provide an adequate aesthetic and functional occlusion, coupled with sound adjunctive periodontal tissue relationships and a favourable long-term prognosis.

Methods

The malocclusion was managed by customised lingual orthodontic appliances and the adjunctive use of direct skeletal anchorage derived from two palatal mini-implants.

Results

The treatment objectives of good aesthetics, a functional occlusion, normal function, a healthy periodontium and a balanced profile were readily achieved. The retention records demonstrate the stability of the correction. The treatment duration was approximately 41 months, which encompassed the use of full fixed customised lingual appliances over a period of 24 months.
The effect of headgear treatment on the development of obstructive sleep apnoea. A systematic review
Authors: Studer Vera , Koletsi Despina , Iliadi Anna , Eliades Theodore
Published: September 2021

Aim

To evaluate the effect of the cervical headgear on the development of obstructive sleep apnoea and subsequent alterations of oropharyngeal dimensions.

Materials and method

An electronic database search of published and unpublished literature was performed (MEDLINE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Clinical Trials.gov and National Research Register). Search terms included obstructive sleep apnoea, sleep disorders, pharyngeal dimensions and headgear. A risk of bias assessment was conducted using the ACROBAT-NRSI tool for non-randomised studies.

Results

Of the 51 articles initially retrieved, only three were eligible for inclusion, while the remainder were retrospective cohort studies presenting serious risk of bias primarily due to undetected confounding factors or selection bias. No quantitative synthesis was possible. One study assessed the potential effect of isolated headgear treatment on apnoeic indices, while two studies described pharyngeal airway dimensions after the use of headgear alone or in combination with an activator appliance. Overall, increased apnoeic indices and the oxygen desaturation index were detected for headgear users. Dimensional changes in the posterior airway space were comparable after headgear or activator use, while combined headgear-activator treatment led to an increase in posterior pharyngeal area when compared with isolated fixed appliance therapy.

Conclusions

Due to methodological inconsistencies and apparent risk of bias of the existing studies, no robust conclusions can be drawn. Prospective controlled or randomised controlled trials are deemed necessary to provide evidence on the effect of headgear treatment on sleep apnoea or pharyngeal airway dimensions.
Dentoskeletal and airway effects of the X-Bow applian ce versus removable functional appliances (Frankel-2 and Trainer) in prepubertal Class II division 1 malocclusion patients
Authors: Atik Ezgi , Görücü-Coşkuner Hande , Kocadereli Ilken
Published: September 2021

Objectives

The aim of the present study was to evaluate the dentoskeletal and airway effects of three different functional appliances (Frankel-2, Trainer and X-Bow) in prepubertal Class II division 1 patients.

Methods

The sample consisted of 54 patients with a Class II relationship as a result of mandibular retrognathia and relative maxillary constriction. Group I included 15 patients treated with a Frankel-2 appliance. Group II consisted of 14 patients treated with a T4-K Trainer. Group III consisted of 15 patients treated with the X-Bow appliance. Group IV consisted of 10 untreated Class II patients who served as a control group. Pretreatment (T1) and post-treatment (T2) cephalograms were used to evaluate dentoskeletal and airway changes. Parametric one-way variance analysis (ANOVA) and a paired t-test were used to perform statistical analysis.

Results

The decrease in SNA angle was significant in groups I and III, compared with the control group (p < 0.05). SNB angle and Co-GN length changes from T1 to T2 were statistically significant in groups I and II (p < 0.05), but not relative to the control group. The upper and lower incisors were significantly retruded and protruded, respectively, in all treatment groups (p < 0.05). Except PNS-AD2 and MAS measurements in group I, nasopharyngeal and oropharyngeal airway dimensions did not significantly change from T1 to T2 in all groups.

Conclusions

The Frankel-2 and X-Bow appliances were efficient in restricting the forward growth of the maxilla. The Frankel-2 and Trainer appliances produced a larger sagittal increase in mandibular length than the X-Bow appliance. Lower incisor proclination was more pronounced in the X-Bow group. The effect of the treatment protocols was similar and matched the control group with respect to the airway.
Influence of facial types on sliding mechanics
Authors: Cadenas-Llano María , Castillo-Oyagüe Raquel , Iglesias-Linares Alejandro , Yáñez-Vico Rosa María , Solano Enrique , Torres-Lagares Daniel
Published: September 2021

Background/objectives/aims

The present study considered the effect of orthodontic friction in an evaluation of the relationship of craniofacial pattern and surface micro-roughness of fixed appliances as determinants of treatment response and time.

Methods

Brachyfacial (BF; N = 17) and dolichofacial (DF; N = 18) patients treated by canine retraction using sliding mechanics, were identified. One archwire and one bracket per patient (those of the hemi-arch showing the fastest space closure of 4 mm) were subjected to confocal scanning microscopic analysis. Total treatment duration, sliding time, tooth movement rate, topographical surface average roughness (Ra), root mean square roughness (RMS), surface-kurtosis (SK), and surface-skewness (SS) were recorded and compared between groups using the Mann-Whitney U test. Correlations between final micro-roughness and treatment time were investigated using Pearson’s coefficient within each craniofacial type (a = 0.05). The post-treatment appliance surfaces were examined by SEM.

Results

BF patients recorded a significantly higher sliding time, lowest retraction rates, and greatest final Ra and RMS (p < 0.001). A comparison of total treatment time and final SK and SS values yielded no significant differences. Significant positive correlations between sliding time and final Ra were identified in both groups.

Conclusions

Compared with DF subjects, BF patients registered higher friction between the orthodontic components, required longer sliding time, and showed lower retraction rates.
Porcelain surface conditioning protocols and shear bond strength of orthodontic brackets
Authors: Lestrade Ashley M. , Ballard Richard W. , Xu Xiaoming , Yu Qingzhao , Kee Edwin L. , Armbruster Paul C.
Published: September 2021

Aim

The objective of the present study was to determine which of six bonding protocols yielded a clinically acceptable shear bond strength (SBS) of metal orthodontic brackets to CAD/CAM lithium disilicate porcelain restorations. A secondary aim was to determine which bonding protocol produced the least surface damage at debond.

Methods

Sixty lithium disilicate samples were fabricated to replicate the facial surface of a mandibular first molar using a CEREC CAD/CAM machine. The samples were split into six test groups, each of which received different mechanical/chemical pretreatment protocols to roughen the porcelain surface prior to bonding a molar orthodontic attachment. Shear bond strength testing was conducted using an Instron machine. The mean, maximum, minimal, and standard deviation SBS values for each sample group including an enamel control were calculated. A t-test was used to evaluate the statistical significance between the groups.

Results

No significant differences were found in SBS values, with the exception of surface roughening with a green stone prior to HFA and silane treatment. This protocol yielded slightly higher bond strength which was statistically significant.

Conclusion

Chemical treatment alone with HFA/silane yielded SBS values within an acceptable clinical range to withstand forces applied by orthodontic treatment and potentially eliminates the need to mechanically roughen the ceramic surface.
Invisalign treatment of lower incisor extraction cases
Authors: Weir Tony
Published: September 2021

Aim

To demonstrate the use of the Invisalign appliance in lower incisor extraction cases.

Method

Twelve patients, consecutively treated by the removal of a single lower incisor and Invisalign appliances, were selected from the author’s private practice. Pretreatment, treatment and post-treatment photographic records were obtained and are presented.

Results

All cases completed treatment, with a mean treatment time of 42 weeks. Fifty percent of the cases required a brief period of refinement (average six weeks) at the end of the initial projected treatment period.

Conclusion

The Invisalign appliance, in correctly diagnosed cases, with careful ‘ClinCheck’ set-ups and good clinical monitoring, can routinely produce satisfactory outcomes in patients who require the removal of a lower incisor.
Fresh stirrings among statisticians: statistical commentary
Authors: Godfrey Keith
Published: September 2021

For some years there has been unrest in the statistical world regarding the use of the p-value. It has been indicated that the significance of p-values is open to question, which therefore reduces the ability to measure the strength of evidence. This paper examines the use and misuse of the p-value and recommends consideration in its application.
The Herbst appliance and the Activator: influence of the vertical facial pattern
Authors: Turnock Christopher , Woods Michael G.
Published: September 2021

Aim

To compare the effects of the Herbst appliance and the Activator at the completion of two-phase treatment, with respect to the vertical facial pattern (VFP) and to identify possible predictors of treatment effect.

Materials and methods

Pretreatment, post-treatment and overall cephalometric change data were used to assess the dental and skeletal effects. Results for the change in mandibular length were also compared with changes reported for an untreated external control group.

Results

Clinically significant dental and skeletal changes (including mandibular incisor proclination and overjet reduction) were characteristics of both treatment methods. Any increases in mandibular length and chin prominence were not greater than those expected following natural growth. The pretreatment VFP remained essentially unaltered, while mean changes as a result of treatment were similar for brachyfacial, mesofacial, and dolichofacial subjects. No predictive factors were identified.

Conclusions

Clinicians are advised to expect significant overjet reduction and mandibular incisor proclination with either treatment method. Significant skeletal change may be observed in growing subjects; however, any increase in mandibular length or chin projection is not likely to be beyond the limit set by nature. While there will be some individual variation, no significant long-term alteration in the pretreatment vertical facial pattern should be expected with either treatment. Long faces will remain long and short faces will remain short.
A computed tomographic, mixed dentition, space analysis comparison
Authors: Queijo Luís , do Vale Francisco , Corte-Real Ana , Alves Sónia
Published: September 2021

Introduction

A considered space analysis aims to predict the combined mesiodistal widths of unerupted permanent canine and premolars. A miscalculation can lead to the application of inadequate and irreversible treatments.

Objective

To assess the level of agreement between predictions generated by three methods (Moyers’ predictive tables at the 50th and 75th percentiles and Tanaka-Johnston’s equations) on the sum of unerupted teeth compared with measurements derived from cone beam computed tomography, considered in the present study as a ‘gold standard’.

Materials and methods

The study sample was comprised of children (N = 26) aged 8–13 who visited the Department of Dentistry. Moyers’ predictive tables and the Tanaka-Johnston equation were applied to ascertain the space requirements. Cone beam computed tomography was performed on each patient and the volumetric data analysed. A concordance correlation coefficient between each method’s predictions was applied.

Results

The three methods tended to overestimate the cone beam computed tomography readings and were not able to entirely capture the variability of the sum of the unerupted teeth. Moyers’ 50th percentile estimate revealed a more balanced distribution between over-and underestimation.

Conclusion

The present study suggested that Moyers’ 50th percentile is the predictive method with the lowest absolute error and is preferred for clinical use.
Effectiveness of photographs of study models for IOTN scoring
Authors: Malik Ovais H. , Stevenson Helen , Mandall N.A. , Alsaeed Mubarak A.
Published: September 2021

Aim

The aim of the present study was to investigate whether the same orthodontic information can be obtained from study models or photographs of study models in order to assess the Index of Orthodontic Treatment Need (IOTN). The study also aimed to assess inter- and intra-examiner reliability in the assessment of orthodontic treatment need.

Sample

Thirty sets of start and finish study models, demonstrating a range of malocclusions, were non-randomly obtained from patients treated at the University of Manchester Dental Hospital. The start models demonstrated a range of malocclusions (according to The British Standard Institute Incisor Classification 1983) of varying complexity.

Method

Six photographic views of each set of study models were taken against a dark background. Millimetric distances were determined by using dividers to measure photographic distances and actual distances in millimeters from a ruler embedded in the image. Four examiners assessed the study models and photographs of the models in a random order and the Aesthetic and Dental Health components of the IOTN were recorded.

Results

There were no statistically significant differences in the IOTN scores from photographs of study models compared with IOTN scores from study models of the same patient.

Conclusion

The IOTN scores derived from photographs of study models are valid and reliable measures of malocclusion.
Evaluation of the mandibular arch in patients with impacted permanent lower canines
Authors: Jain Shikha , Agrawal Mamta , Jain Sachin , Jain Shweta
Published: September 2021

Aim

To determine the features of the mandibular dental arch in subjects presenting with impacted permanent lower canines.

Methods

The ‘impaction group’ consisted of 48 Indian subjects with mandibular canine impaction (Females:Males, 1.5:1; mean age, 15.03 ± 0.49 years). The ‘control group’ was comprised of 96 age-, gender- and malocclusion-matched Indians who were randomly selected from subjects initially screened but who had completely erupted mandibular canines. Arch width, arch length, arch shape and space status (total tooth size, arch-length – tooth-size discrepancy) were assessed using dental models and were compared between the groups using comparative measurements and statistics.

Results

Statistically significant differences were demonstrated with respect to the arch length, arch shape, total tooth size and arch-length – tooth-size discrepancy (p = 0.03, 0.02, 0.04, 0.01; independent 2-sample t-tests, respectively). Crowding was more prevalent in subjects with impaction than in the controls, with the difference being statistically significant (chi-square = 13.202; degrees of freedom (df) = 4; p = 0.010).

Conclusion

Patients with permanent mandibular canine impaction have adequately wide but shorter lower dental arch forms along with wider mandibular total tooth size and greater arch-length – tooth-size discrepancy when compared with a control sample.
An evaluation of the antibacterial properties and shear bond strength of copper nanoparticles as a nanofiller in orthodontic adhesive
Authors: Argueta-Figueroa Liliana , Scougall-Vilchis Rogelio J. , Morales-Luckie Raúl A. , Olea-Mejía Oscar F.
Published: September 2021

Objectives

To evaluate the antibacterial properties and effects of an orthodontic adhesive containing copper nanoparticles (NPs) on the material’s shear bond strength.

Methods

Antimicrobial activity was analysed by a disk diffusion test against S. aureus, E. coli and S. mutans. The NPs were added to the orthodontic adhesive at 0.0100 wt%, 0.0075 wt%, and 0.0050 wt%. Sixty extracted bicuspids were divided into two groups and the enamel of all teeth was conditioned with phosphoric acid. A coat of moisture insensitive primer (MIP) was applied prior to the bonding of brackets with composite resin. Group I served as a control and the bonding procedure was performed according to the manufacturer’s instructions. Group II comprised the test teeth, into which 0.0100 wt% copper NPs were included in the MIP Samples were tested and statistically analysed (p ≤ 0.05). The adhesive remnant index (ARI) was also assessed microscopically.

Results

The adhesive with copper NPs showed a bactericidal effect against the bacteria under study. A significantly higher bond strength was obtained with the orthodontic adhesive that included 0.0100 wt% of copper NPs (15.23 ± 6.8 MPa) in comparison with the control group (9.59 ± 4.3 MPa). The ARI scores indicated that the groups were significantly different and strengthened by the incorporation of NPs (p = 0.004).

Conclusion

The results of the present study suggested that an orthodontic adhesive, which included copper NPs, significantly increased material shear bond strength without adverse side effects on colour and appearance. The adhesive interface was strengthened by homogeneously dispersed copper NPs added as a nanofiller.