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Treatment of vertical problems with jaw functional orthopedics based on scientific evidence. Part 1: anterior open bite
Get PDFThe vertical problems of the stomatognathic system that alter the overbite, either by increasing in the deep bite (DB) or decreasing in the anterior open bite (AOB), are among the great challenges of the dentofacial corrections in the treatment and the retention and stability protocols. It is always good to report that a correct diagnosis is fundamental in the choice of treatment protocol and that skeletal involvement, be it hyper divergence in case of open bite or hypo divergence in case of deep bite, aggravates the problem and as a rule tends to increase treatment and containment time. In this paper the state of art of AOB treatment with Jaw Functional Orthopedics (JFO) will be discussed. It should be emphasized that JFO has a unique diagnostic tool for changes in vertical growth of the face, the Articular Compass, developed by Simões. Studies show that the use of treatment protocols developed by Simões, the SNs (SN2, SN3, SN6) act in the increase of overbite efficiently (P= 0.003) in cases of open bite. This is weak evidence, due to the design of the study, but with promising results, so Randomized Clinical Trials are needed to investigate if these results are replicable
Tongue-and lip-tie beyond breastfeeding difficulties
Get PDFThe diagnosis and treatment of tethered oral tie tissues, such as ankyloglossia (tongue-tie) and lip-tie, have grown substantially. Although robust evidence indicates that these abnormal anatomic variations are associated with breastfeeding difficulties, impaired craniofacial growth, sleep, speech and posture in children, both diagnosis and treatment of oral ties remain controversial. The oral cavity displays considerable morphological variation across individuals. One of these variations includes tight, restrictive connective tissue between oral structures known as tethered oral tie tissues (TOTs). The clinical view regarding these anomalies has evolved with increasing interest not only in tongue-tie (ankyloglossia) but also in lip-tie [1-3]. Ankyloglossia has been considered a risk factor for breastfeeding difficulties [4-16]. Recent evidence indicates that TOTs can be also associated with whole-body consequences, such as reflux, dental malocclusion, and respiratory disorders, ultimately increasing the risk of sleep and speech disorders, and detrimental changes in posture and eating patterns [13, 17-25]. The prevalence of TOTs is highly variable across populations and is still a matter of ample debate. Currently, there is a lack of consensus on diagnosis criteria, best surgical treatment techniques, and pre- and post-surgery care [19, 26, 27]. Yet, the diagnosis and surgical treatment of TOTs have substantially increased in recent years [28-31]. This mini-review will summarize evidence-based data regarding the cascade of consequences of tongue-tie and lip-tie in children and the main signs and symptoms of these anomalies in newborns. It will also discuss the available evidence on treatment options for TOTs, including pre- and post-surgical care that may enable better outcomes and prevention of possible complications. For a better understanding, tongue-tie and lip-tie will be addressed separately
Is jaw functional orthopedics an efficient tool to treat anterior open bite? A retrospective study
Get PDFAnterior Open Bite (AOB) is a malocclusion for which the choice of a treatment protocol it is challenging. There are some protocols that have been shown to be effective for open bite treatment. The aim of this investigation was to study the behavior of overbite during AOB treatment with Jaw Functional Orthopedics (JFO). The behavior of overbite was studied retrospectively in 17 patients treated in the Specialization Course in (JFO – ABO Muriaé (Muriaé, MG Brazil). Monthly overbite measurements in millimeters were taken with a pachymeter and the data were stored in an individual paper worksheet. Data obtained before functional appliance installation (T0) and after 12-months of treatment (T1) were compared. Wilcoxon non-parametric test for 2 paired samples was use for statical treatment of the data. P= 0.003 for overbite comparison T1-T0. It could be concluded that Functional orthopedic appliance has shown to be an effective tool for treating anterior open bite in the sample studied. Further studies, mainly Randomized Clinical Trials, with larger samples are necessary to confirm this result and to study stability and skeletal behavior in anterior open bite treated with Jaw Functional orthopedics
Experiment and analysis of active vibration isolation system based on rigid pedestal using SDOF actuator
Get PDFThis paper is about the active-passive isolation system based on single degree of freedom electromagnetic actuator and focuses on different control effect of different measure points. In view of this problem, the authors analyze the vibration characteristics of the active and passive vibration isolation systems of electromagnetic airbags under single and multi-vibration isolators. Then they decompose the rigid pedestal vibration into two orthogonal components, the vertical translation and the fix axis rotation. After that compare simulation and experiment results in terms of the control effect when the single active-passive isolator location varies. Finally, the authors draw a conclusion about the reason why the rigid pedestal vibration can be globally controlled by arranging more than 3 active-passive isolations and design a multiple isolator system experiment to verify
Assessing the nonlinear static stiffness of rail pad using finite element method
Get PDFThe unintended vibrations and sound emerging from train operation have an enormous impact on the surroundings, including the deterioration of the way, buildings, and structures. One proposed strategy to mitigate this issue is the installation of a rail pad inserted between the steel rail and concrete sleeper to provide flexibility to the track and cushion the shocks and vibrations generated by the train wheels’ movement. These materials have nonlinear, dissipative properties influenced by service conditions like temperature and toe load. This work aimed to investigate the static stiffness of different materials of the rail pad under the influence of temperature and toe load. The rail pads were categorized as soft, medium, or hard based on static stiffness. A 3D model of the rail pad, steel rail, and concrete sleeper was simulated and analyzed using ANSYS FEM software. The neo-Hookean model was used to model the rail pad, and the isotropic elasticity model was used for the steel rail and concrete sleeper. The static stiffness of the ethylene propylene diene monomer (EPDM) pad was 85.42 kN/mm, lower than that of thermoplastic elastomers (TPEs, 138.98 kN/mm) and ethylene vinyl acetate (EVA, 303.70 kN/mm) under reference conditions (20 °C), without including toe load effects. Increasing the temperature decreased the rail pad’s static stiffness, with the highest reduction of 53.49 %. However, increasing the toe load contributed up to a 23.53 % increase in the static stiffness of the rail pad
Parameter estimation of underwater propeller based on inverse Radon transform
Get PDFAiming at improving the method of underwater target recognition, this paper proposes a method to estimate the micro-Doppler spectrum parameters of propeller by using inverse Radon transform, so as to obtain the characteristic parameters of propeller. This paper firstly analyzes the basic concepts of micro-Doppler and inverse Radon transform, then defines the algorithm steps of inverse Radon transform for propeller parameter estimation and carries out simulation. The simulation results show that this method can effectively estimate the propeller rotational speed, blade number, blade length and initial spatial position
Simulation and experimental investigation of kinematic characteristics of the wheeled in-pipe robot actuated by the unbalanced rotor
Get PDFMobile robotic systems are currently of significant interest due to the wide range of possible applications. Among a great variety of mobile robots, specific attention is paid to the wheeled ones. The main purpose of this research consists in substantiating the possibilities of improving the vibration-driven robot equipped with the unidirectionally rotating wheels. The methodology of the present study contains the development of the robot’s 3D-model in the SolidWorks software, constructing the simplified dynamic diagram of the robot’s oscillatory system, and developing its simulation model in the MapleSim software. The research results are obtained by numerical solving of the motion equations in the MapleSim software, by simulating the robot locomotion conditions in the SolidWorks software, and by conducting experiments. The results present the main kinematic characteristics of the robot motion under different operational conditions. The major scientific novelty of this paper consists in developing the improved design of the wheeled robot driven by the centrifugal (inertial) vibration exciter and substantiating its operational peculiarities. The obtained results can be effectively used while creating the production prototypes of mobile robotic systems, particularly those for cleaning the pipelines and monitoring (inspecting) their inner surfaces, welds, joints, couplings, etc
Effect of acoustic black hole parameters on vibration suppression of rectangular plate
Get PDFThe acoustic black hole has the ability to gather and manipulate the flexural wave in the structure, and can be used to achieve vibration suppression of the structure. A group of FEM models for the vibration analysis of the rectangular plate embedded with acoustic black holes were established in this paper. Four monitoring points on the ABH plate were selected to calculate their vibration velocity response in 100 Hz-3 kHz frequency interval. In order to study the effects of acoustic black hole geometric parameters and damping layer geometric parameters on the vibration response of the ABH plate, 15 combinations of different parameters of the maximum ABH diameter, the truncated thickness of the ABH, the power index of the ABH, and the damping layer thickness, the maximum diameter of the damping layer were selected to calculate the vibration velocity response of the four monitoring points. The calculation result can help us understand the effects of acoustic black hole geometric parameters and damping layer geometric parameters on the vibration suppression of rectangular plate
Sloshing mitigation using vertical cylindrical baffle
Get PDFThis study has looked into the phenomenon of liquid vibrations in a rigid cylindrical container. The impacts of rigid vertical baffle positioned in the container on frequencies have been examined. The container is partially filled with an impermeable and non-viscous fluid. ANSYS software is used to report the mode shapes of the baffle and fluid domain
Simulation of dynamic performance and wheel-rail wear of railway wagon under deviation of cargo gravity center
Get PDFA multibody dynamic model of railway wagon is established by Simpack software, and the derailment coefficient, wheel load reduction rate, impact angle and wear index of freight car are calculated under different gravity center offsets and different curve conditions. The simulation results show that the lateral and longitudinal offsets of cargo gravity center have a great influence on the derailment coefficient, wheel unloading rate, impact angle and wear index of the vehicle. The larger the offset of the cargo gravity center is, the worse the operation performance of the wagon is, the more serious the wheel-rail wear is, and the shorter the transport life of the wagon is. The smaller the radius of the curve is, the greater the impact is