Receptive Field Properties of Human Periodontal Afferents Responding to Loading of Premolar and Molar Teeth

2003 ◽  
Vol 89 (3) ◽  
pp. 1478-1487 ◽  
Author(s):  
Skjalg E. Johnsen ◽  
Mats Trulsson
Keyword(s):  
Horizontal Plane ◽  
Vertical Plane ◽  
Inferior Alveolar Nerve ◽  
Vertical Direction ◽  
Dental Arch ◽  
Posterior Teeth ◽  
Directional Bias ◽  
Mechanical Coupling ◽  
Molar Teeth ◽  
Stimulation Of

Impulses in 45 single mechanoreceptive afferents were recorded from the human inferior alveolar nerve with permucosally inserted tungsten microelectrodes. All afferents responded to mechanical stimulation of one or more premolar or molar teeth and most likely innervated their periodontal ligaments. For each afferent, isolated “ramp-and-hold” shaped force profiles of similar magnitudes (252 ± 24 mN; mean ± SD) were applied to the lower first premolar, the second premolar, and the first molar on the recording side. The tooth loads were applied in six directions: lingual, facial, mesial, and distal in the horizontal plane and up and down in the vertical direction of the tooth. The afferents response during the static phase of the stimulus was analyzed. All afferents were slowly adapting, discharging continuously in response to static forces in at least one stimulation direction. Twenty-nine afferents (64%) were spontaneously active, exhibiting an ongoing discharge in the absence of external stimulation. Stimulation of a single tooth was found to excite each afferent most strongly. The most sensitive tooth (MST) was the first premolar for 23, the second premolar for 13, and the first molar for 9 afferents. About half of the afferent population also responded to loading of one or two more teeth. The response profiles of these afferents indicated that the multiple-teeth receptive fields were due to mechanical coupling between the teeth rather than branching of single afferents to innervate several teeth. The afferent responses to loading the mesial and distal halves of the first molars were very similar. Thus both intensive and directional aspects of the afferent response when loading one side of the tooth was preserved to a great extent when loading the other side. When loading the MST, the afferents typically showed excitatory responses in two to four of the six stimulation directions, i.e., the afferents were broadly tuned to direction of tooth loading. In the horizontal plane, the afferent populations at the premolar teeth expressed no clear directional preferences. The afferents at the molar, however, showed a strong directional bias in the distal-lingual direction. In the vertical plane, there was a preference for downward-directed forces with a gradually decreasing sensitivity distally along the dental arch. The present results demonstrate that human periodontal afferents supplying anterior and posterior teeth differ in their capacity to signal horizontal and vertical forces, respectively.

scholarly journals Dielectric anisotropy as indicator of crystal orientation fabric in Dome Fuji ice core: method and initial results

2021 ◽  
pp. 1-12
Author(s):  
Tomotaka Saruya ◽  
Shuji Fujita ◽  
Ryo Inoue
Keyword(s):  
Crystal Orientation ◽  
Horizontal Plane ◽  
Ice Core ◽  
Vertical Plane ◽  
Vertical Direction ◽  
Core Sample ◽  
Dielectric Anisotropy ◽  
Principal Axes ◽  
Polycrystalline Ice ◽  
Initial Results

Abstract Polycrystalline ice is known to exhibit macroscopic anisotropy in relative permittivity (ɛ) depending on the crystal orientation fabric (COF). Using a new system designed to measure the tensorial components of ɛ, we investigated the dielectric anisotropy (Δɛ) of a deep ice core sample obtained from Dome Fuji, East Antarctica. This technique permits the continuous nondestructive assessment of the COF in thick ice sections. Measurements of vertical prism sections along the core showed that the Δɛ values in the vertical direction increased with increasing depth, supporting previous findings of c-axis clustering around the vertical direction. Analyses of horizontal disk sections demonstrated that the magnitude of Δɛ in the horizontal plane was 10–15% of that in the vertical plane. In addition, the directions of the principal axes of tensorial ɛ in the horizontal plane corresponded to the long or short axis of the elliptically elongated single-pole maximum COF. The data confirmed that Δɛ in the vertical and horizontal planes adequately indicated the preferred orientations of the c-axes, and that Δɛ can be considered to represent a direct substitute for the normalized COF eigenvalues. This new method could be extremely useful as a means of investigating continuous and depth-dependent variations in COF.

Coherent Structures in Shallow Water Jets

2011 ◽  
Vol 133 (1) ◽  
Author(s):  
A.-M. Shinneeb ◽  
J. D. Bugg ◽  
R. Balachandar
Keyword(s):  
Coherent Structures ◽  
Horizontal Plane ◽  
Large Scale ◽  
Solid Wall ◽  
Vertical Wall ◽  
Vertical Plane ◽  
Vertical Direction ◽  
Particle Image Velocimetry System ◽  
Identification Algorithm ◽  
Vortical Structures

This paper reports an experimental investigation of a round jet discharging horizontally from a vertical wall into an isothermal body of water confined in the vertical direction by a flat wall on the bottom and a free surface on top. Specifically, this paper focuses on the effects of vertical confinement on the characteristics of large vortical structures. The jet exit velocity was 2.5 m/s, and the exit Reynolds number was 22,500. Experiments were performed at water layer depths corresponding to 15, 10, and 5 times the jet exit diameter (9 mm). The large-scale structures were exposed by performing a proper orthogonal decomposition (POD) analysis of the velocity field obtained using a particle image velocimetry system. Measurements were made on vertical and horizontal planes—both containing the axis of the jet. All fields-of-view were positioned at an axial location in the range 10<x/D<80. The number of modes used for the POD reconstruction of the velocity fields was selected to recover ∼40% of the turbulent kinetic energy. A vortex identification algorithm was then employed to quantify the size, circulation, and direction of rotation of the exposed vortices. A statistical analysis of the distribution of number, size, and strength of the identified vortices was carried out to explore the characteristics of the coherent structures. The results clearly reveal the existence of numerous vortical structures of both rotational senses in the jet flow, and their number generally decreases in the axial direction while their size increases. The size of vortices identified in the vertical plane is restricted by the water depth, while they are allowed to increase in size in the horizontal plane. Moreover, the results show a significant decrease in the number of small vortices for the shallowest case in the horizontal plane, with a corresponding increase in the number of large vortices and a significant increase in their size. This behavior was accompanied with an increase in the vortex circulation in the horizontal plane and a reduction in the circulation in the vertical plane. This is indicative of the dominance of the pairing process due to shallowness. Moreover, the balance between the positive and negative vortices in the vertical plane changed because of the formation of negative (clockwise) vortices near the solid wall at downstream locations.

scholarly journals A Prototype Orthogonal Vertical Beamforming for Indoor Wireless Communications

2021 ◽  
pp. 516-521
Author(s):  
Paleerat Wongchampa ◽  
Keyword(s):  
Error Rate ◽  
Horizontal Plane ◽  
Indoor Environment ◽  
Vertical Plane ◽  
Vertical Direction ◽  
Signal Interference ◽  
Packet Error Rate ◽  
Indoor Wireless ◽  
Orthogonal Property ◽  
Indoor Wireless Communications

The concept of Orthogonal Vertical Beamforming (OVB) is proposed in this paper to eliminate interference when users remain at the same angle in the horizontal plane but are positioned at different distances. This orthogonal property helps systems avoid interference in the vertical direction of the mainbeam. A fully constructed prototype tested in a real indoor environment validates the proposed concept, revealing that the proposed OVB provides higher Signal Interference plus Noise Ratio (SINR) and Packet Error Rate (PER) in the vertical plane than conventional vertical beamforming and Orthogonal Beamforming.

scholarly journals Millimeter-wave multi-mode circular antenna array for uni-cast multi-cast and OAM communication

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Stylianos D. Assimonis ◽  
Muhammad Ali Babar Abbasi ◽  
Vincent Fusco
Keyword(s):  
Antenna Array ◽  
Radiation Pattern ◽  
Data Transmission ◽  
Electromagnetic Waves ◽  
Horizontal Plane ◽  
Impedance Matching ◽  
Vertical Plane ◽  
Vertical Direction ◽  
Low Complexity ◽  
Circular Antenna Array

AbstractThis paper investigates uni-/multi-cast and orbital angular momentum (OAM) mode data transmission in orthogonal directions by the utilization of a new circular antenna array, operating at 28 GHz. In the horizontal plane the proposed antenna array operates as multimode transmitter (i.e., it provides broad-, uni- and/or multi-cast communication), while in the vertical direction OAM transmission occurs (i.e., it is capable of generating up to 15 spatially orthogonal OAM modes). Antenna array is designed using twelve, low-complexity, electromagnetically coupled microstrip patch antennas with high radiation efficiency. Each of these can transmit power of equivalent order of magnitude in both horizontal (i.e., broadside radiation pattern) and vertical direction (i.e., endfire radiation pattern) over electromagnetic waves of orthogonal electric components. This property leads to the formation of uni-/multi-cast and OAM modes in the horizontal plane and vertical direction, respectively. Antenna was tested through full-wave electromagnetic analysis and measurements in terms of impedance matching, mutual coupling and radiation pattern: good agreement between simulated and measurement results was observed. Specifically, it presents up to 8.65 dBi and 6.48 dBi realized gain under the uni-cast (in the horizontal plane) and OAM mode (in the vertical plane), respectively. The proposed antenna array is perfect candidate for high spectral efficiency data transmission for 5G and beyond wireless applications, where orthogonality in communication links and OAM multiplexing is a requirement.

scholarly journals RCT on the effectiveness of the intraligamentary anesthesia and inferior alveolar nerve block on pain during dental treatment

2021 ◽  
Author(s):  
Bahaa R. Youssef ◽  
Andreas Söhnel ◽  
Alexander Welk ◽  
Mohamed H. Abudrya ◽  
Mohamed Baider ◽  
...  
Keyword(s):  
Postoperative Complications ◽  
Nerve Block ◽  
Rating Scale ◽  
Dental Treatment ◽  
Inferior Alveolar Nerve ◽  
Numeric Rating Scale ◽  
Inferior Alveolar Nerve Block ◽  
Posterior Teeth ◽  
Mandibular Posterior Teeth ◽  
Numeric Rating

Abstract Objective To compare the effectiveness and complications of intraligamentary anesthesia (ILA) with conventional inferior alveolar nerve block (IANB) during injection and dental treatment of mandibular posterior teeth. Materials and methods In this randomized, prospective clinical trial, 72 patients (39 males, 33 females), scheduled for dental treatment of mandibular posterior teeth, were randomly allocated to ILA group (n = 35) received ILA injection or IANB group (n = 37) received the conventional IANB. Our primary outcome was to assess pain and stress (discomfort) during the injection and dental treatment, using the numeric rating scale (NRS) from 0 to 10 (0 = no pain, 10= the worst pain imaginable), whereas recording 24-h postoperative complications was our secondary outcomes. Results Patients in ILA group reported significantly less pain during injection when compared with IANB group (p = 0.03), while pain during dental treatment was similar in both groups (p = 0.2). Patients in both groups also reported similar law values of discomfort during treatment (p = 0.7). Although no signs of nerve contact or any other postoperative complications were observed, five patients in IANB group (none in ILA group) reported temporary irritations. Conclusion This study showed equivalent effectiveness of both intraligamentary anesthesia and conventional inferior alveolar nerve block, for pain control during routine dental treatment of mandibular posterior teeth. Nevertheless, ILA showed significantly less pain during injection. No major postoperative complications in both groups were observed. Clinical relevance ILA could be considered as an effective alternative for routine dental treatment. Trial registration NCT04563351

scholarly journals Anesthetic Efficacy of a Combination of 0.5 M Mannitol Plus 127.2 mg of Lidocaine With 50 μg Epinephrine in Inferior Alveolar Nerve Blocks: A Prospective Randomized, Single-Blind Study

2013 ◽  
Vol 60 (1) ◽  
pp. 3-10 ◽  
Author(s):  
Steven Smith ◽  
Al Reader ◽  
Melissa Drum ◽  
John Nusstein ◽  
Mike Beck
Keyword(s):  
Postoperative Pain ◽  
Inferior Alveolar Nerve ◽  
Blind Study ◽  
Maximum Output ◽  
Nerve Blocks ◽  
Posterior Teeth ◽  
Solution Deposition ◽  
The Times ◽  
Pulpal Anesthesia ◽  
Single Blind

Abstract The purpose of this prospective, randomized, single-blind study was to determine the anesthetic efficacy of 127.2 mg lidocaine with 50 μg epinephrine compared to 127.2 mg lidocaine with 50 μg epinephrine plus 0.5 M mannitol in inferior alveolar nerve (IAN) blocks. Forty subjects randomly received 2 IAN blocks consisting of a 3.18 mL formulation of 127.2 mg lidocaine with 50 μg epinephrine and a 5 mL formulation of 127.2 mg lidocaine with 50 μg epinephrine (3.18 mL) plus 0.5 M mannitol (1.82 mL) in 2 separate appointments spaced at least 1 week apart. Mandibular anterior and posterior teeth were blindly electric pulp tested at 4-minute cycles for 60 minutes postinjection. Pain of solution deposition and postoperative pain were also measured. No response from the subject to the maximum output (80 reading) of the pulp tester was used as the criterion for pulpal anesthesia. Total percent pulpal anesthesia was defined as the total of all the times of pulpal anesthesia (80 readings) over the 60 minutes. One hundred percent of the subjects had profound lip numbness with both inferior alveolar nerve blocks. The results demonstrated that a 5 mL formulation of 127.2 mg lidocaine with 50 μg epinephrine plus 0.5 M mannitol was significantly better than the 3.18 mL formulation of 127.2 mg lidocaine with 50 μg epinephrine for all teeth. Solution deposition pain and postoperative pain were not statistically different between the lidocaine/mannitol formulation and the lidocaine formulation without mannitol. We concluded that adding 0.5 M mannitol to a lidocaine with epinephrine formulation was significantly more effective in achieving a greater percentage of total pulpal anesthesia than a lidocaine formulation without mannitol.

scholarly journals Horizontal versus vertical charge and energy transfer in hybrid assemblies of semiconductor nanoparticles

2012 ◽  
Vol 3 ◽  
pp. 629-636 ◽  
Author(s):  
Gilad Gotesman ◽  
Rahamim Guliamov ◽  
Ron Naaman
Keyword(s):  
Energy Transfer ◽  
Charge Transfer ◽  
Horizontal Plane ◽  
Quartz Substrate ◽  
Vertical Direction ◽  
Time Resolved ◽  
Transfer Processes ◽  
Donor And Acceptor ◽  
Hybrid Assemblies ◽  
Time Resolved Photoluminescence

We studied the photoluminescence and time-resolved photoluminescence from self-assembled bilayers of donor and acceptor nanoparticles (NPs) adsorbed on a quartz substrate through organic linkers. Charge and energy transfer processes within the assemblies were investigated as a function of the length of the dithiolated linker (DT) between the donors and acceptors. We found an unusual linker-length-dependency in the emission of the donors. This dependency may be explained by charge and energy transfer processes in the vertical direction (from the donors to the acceptors) that depend strongly on charge transfer processes occurring in the horizontal plane (within the monolayer of the acceptor), namely, parallel to the substrate.

Treatment of deep overbite in mixed dentition: a clinical case report

2021 ◽  
Vol 21 (2) ◽  
pp. 132-137
Author(s):  
A. S. Shishmareva ◽  
E. S. Bimbas ◽  
E. V. Menshikova
Keyword(s):  
Mixed Dentition ◽  
Dental Arch ◽  
Treatment Results ◽  
Harmonious Development ◽  
Posterior Teeth ◽  
Deep Bite ◽  
Curve Of Spee ◽  
Suggested Technique ◽  
Short Period ◽  
Distal Occlusion

Relevance. Deep overbite is one of the most frequent malocclusions in children and teenagers of different ages. Distal occlusion with a deep overbite is the most common (59.6-67.6% according to the literature) in early mixed dentition. Most Russian and international authors state in their research that the severity of malocclusion increases with age. The treatment of the pathology in children is relevant due to deterioration of the deep overbite with age, worsening of functional disorders.Materials and methods. The study analyses the treatment results of a child with a deep bite using the authors’ technique.Results. The study demonstrated the advantages of the authors’ technique. The treatment allowed achieving normal dentoalveolar heights in the posterior mandible on molar and premolar eruption, establishing the correct relationship between the upper and lower dental arches that promoted harmonious development of the child’s maxillofacial area. The treatment regulated the length and width of the upper dental arch and corrected its form. The active intrusion of the lower incisors and extrusion of the lower posterior teeth were observed during the treatment. The curve of Spee was restored, and an increased overlap reduced. Occlusal contacts of posterior teeth improved, and deep overbite decreased. The technique is easy to use and allows curing 9-12-year-old children in a short period (7-10 months).Conclusions. The suggested technique treats deep overbite as well as creates conditions for the further harmonious development of the maxillofacial area. Thus, it can be recommended for the treatment in early mixed dentition.

scholarly journals A New Method for the Calculation of Energy and Power Requirements of Bucket Wheel Excavators

2019 ◽  
Vol 10 (1) ◽  
pp. 15-20
Author(s):  
József András ◽  
József Kovács ◽  
Endre András ◽  
Ildikó Kertész ◽  
Ovidiu Bogdan Tomus
Keyword(s):  
Energy Consumption ◽  
Numerical Method ◽  
Horizontal Plane ◽  
Vertical Plane ◽  
New Method ◽  
Energy Requirements ◽  
Belt Conveyor ◽  
Analytical Formulas ◽  
Power And Energy ◽  
Continuous Working

Abstract The bucket wheel excavator (BWE) is a continuous working rock harvesting device which removes the rock by means of buckets armoured with teeth, mounted on the wheel and which transfers rock on a main hauling system (generally a belt conveyor). The wheel rotates in a vertical plane and swings in the horizontal plane and raised / descended in the vertical plane by a boom. In this paper we propose a graphical-numerical method in order to calculate the power and energy requirements of the main harvesting structure (the bucket wheel) of the BWE. This approach - based on virtual models of the main working units of bucket wheel excavators and their working processes - is more convenient than those based on analytical formulas and simplification hypotheses, and leads to improved operation, reduced energy consumption, increased productivity and optimal use of available actuating power.

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