Effects of Different Gum Hardness on Masseter Muscle Activity During Gum Chewing: An NIRS Oximetry Study.

Gum chewing is used in orofacial therapy to improve oral functions, such as a patient's chewing ability, bite force, tongue pressure, and lip closure strength. However, its effects on masseter muscle oxygen dynamics and muscle activity may vary with the hardness and features of the gum base. Therefore, when considering gum chewing for therapeutic purposes, it is essential to select gum of an appropriate hardness.

Effect of Gum Chewing Training on Masseter Muscle Oxygen Dynamics.

This study aimed to clarify the effect of 1 month of gum chewing (GCh) training on masseter muscle oxygen dynamics and determine its effectiveness in improving muscle endurance and fatigue. A total of 16 healthy adult subjects were included in this study. The subjects were randomly assigned to two groups: control and training groups (eight subjects each).

Effects of Dual Tasks Including Gum Chewing on Prefrontal Cortex Activity.

The purpose of this study was to examine the effects on prefrontal cortex (PFC) activity of listening to pleasant sounds (PS) while walking, gum chewing (GCh), or performing the dual task of walking and gum chewing at the same time (walking + GCh). A total of 11 healthy adult male volunteers participated in the study (mean age: 29.54 ± 3.

rs12411980 single-nucleotide polymorphism related to expression is significantly associated with phantom tooth pain.

Phantom tooth pain (PTP) is one type of non-odontogenic neuropathic toothache, which rarely occurs after appropriate pulpectomy or tooth extraction. The cause of PTP is unknown. We investigated pain-related genetic factors that are associated with PTP.

Effect of Vinyl Acetate, Glass Fibers Contents, and Buffer Space on EVA's Mechanical Property and Shock Absorption Ability.

Objectives:  The aim of the study was to evaluate the mechanical properties and impact absorption capacity of prototype materials comprising ethylene vinyl acetate (EVA) of different hardness reinforced using different amounts of glass fibers (GFs), considering a buffer space.

Materials And Methods: Six prototype materials were made by adding E-GFs (5 and 10 wt%) to EVA with vinyl acetate (VA) contents of 9.4 wt% ("hard" or HA) and 27.

Single-Nucleotide Polymorphisms of the and Genes Are Significantly Associated with Chronic Pain.

Patients with chronic pain are affected psychologically and socially. There are also individual differences in treatment efficacy. Insufficient research has been conducted on genetic polymorphisms that are related to individual differences in the susceptibility to chronic pain.

Intracellular cAMP Signaling Pathway via G Protein-Coupled Receptor Activation in Rat Primary Cultured Trigeminal Ganglion Cells.

G protein-coupled receptors in trigeminal ganglion (TG) neurons are often associated with sensory mechanisms, including nociception. We have previously reported the expression of P2Y receptors, which are G protein-coupled receptors, in TG cells. Activating P2Y receptors decreased the intracellular free Ca concentration ([Ca]).

Clinical Application of Inferior Alveolar Nerve Block Device for Safe and Secure IANB by Any Operator.

The inferior alveolar nerve block (IANB) is an established technique with a success rate of 60-80%; however, large errors have been reported among operators. Some dentists do not prefer to use IANB because of the risk of complications. Nevertheless, it is a useful technique for pain control, and a secure IANB offers significant benefits to operators and patients.

The rs216009 single-nucleotide polymorphism of the gene is associated with phantom tooth pain.

Phantom tooth pain (PTP) is a rare and specific neuropathic pain that occurs after pulpectomy and tooth extraction, but its cause is not understood. We hypothesized that there is a genetic contribution to PTP. The present study focused on the gene, which encodes the α1C subunit of the Ca1.

Improvement in persistent idiopathic facial pain with comorbid ADHD using the combination of a dopamine system stabilizer and psychostimulant: A case report.

Key Clinical Message: Persistent idiopathic facial pain (PIFP) and attention-deficit/hyperactivity disorder (ADHD) may coexist and can be improved with ADHD medications. Thus, clinicians should screen for ADHD by a multidisciplinary approach when treating PIFP and differentiate between other odontogenic disorders.

Abstract: We report a case of a woman with persistent idiopathic facial pain (PIFP) and attention-deficit/hyperactivity disorder (ADHD) that markedly improved with the administration of a combination of aripiprazole (APZ) and methylphenidate (MP) treatment.

Genetic Polymorphisms of Are Possibly Associated with Pain Severity and Opioid Dose Requirements in Patients with Inflammatory Pain Conditions: Clinical Observation Study.

Autotaxin, encoded by the gene, is a known key element of neuropathic pain; however, its involvement in nociceptive pain processing remains unclear. We explored the associations between postoperative pain intensity, 24-h postoperative opioid dose requirements, and 93 -gene single-nucleotide polymorphisms (SNPs) in 362 healthy patients who underwent cosmetic surgery using the dominant, recessive, and genotypic models. Next, we validated the associations between relevant SNPs on the one hand and pain intensity and daily opioid dosages on the other in 89 patients with cancer-related pain.

Effects of Myostatin on Nuclear Morphology at the Myotendinous Junction.

Myostatin (Myo) is known to suppress skeletal muscle growth, and was recently reported to control tendon homeostasis. The purpose of the present study was to investigate the regulatory involvement of Myo in the myotendinous junction (MTJ) in vivo and in vitro. After Achilles tendon injury in mice, we identified unexpected cell accumulation on the tendon side of the MTJ.

Head injuries caused by contact with teeth during sports and exercise activities in Japanese schools during the period 2012-2018.

Background/aim: During sports activities, teeth-related contact can cause injury to both ally and opponent players, which can lead to potential infections and aesthetic problems. However, the extent of such injuries remains unclear. This study aimed to clarify the frequency and situation of head injuries caused by teeth (HICBT) occurring under the supervision of schools in Japan.

Diagnosis and treatment of intractable idiopathic orofacial pain with attention-deficit/hyperactivity disorder.

Attention-deficit/hyperactivity disorder (ADHD) has been reported to be associated with primary chronic pain syndromes, such as fibromyalgia, migraine, and chronic low back pain. Although idiopathic orofacial pain (IOP) is classified as burning mouth syndrome or persistent idiopathic facial or dentoalveolar pain and as a primary chronic pain, the association between IOP and ADHD has not been investigated. This retrospective cohort study investigated the severity of ADHD symptoms measured using the ADHD scale and the effects of treatment using ADHD drugs and the dopamine system stabilizer aripiprazole.

Rs11726196 Single-Nucleotide Polymorphism of the Transient Receptor Potential Canonical 3 () Gene Is Associated with Chronic Pain.

Chronic pain is reportedly associated with the transient receptor potential canonical 3 () gene. The present study examined the genetic associations between the single-nucleotide polymorphisms (SNPs) of the gene and chronic pain. The genomic samples from 194 patients underwent linkage disequilibrium (LD) analyses of 29 SNPs within and around the vicinity of the gene.

Jaw-Clenching Intensity Effects on Masseter Oxygen Dynamics and Fatigue: A NIRS Oximetry Study.

The purpose of this study was to clarify the effects of jaw-clenching intensity on masseter muscle oxygen dynamics during clenching and recovery and masseter muscle fatigue using the spatially resolved method of near-infrared spectroscopy. Pulse rate, mean power frequency from electromyography in the masseter and visual analogue scale for masseter fatigue were also examined as related items. The 25% and 50% maximum voluntary contractions were determined using electromyography before the experiment and used as visual feedback on the screen.

Improving light-cured intermediate resin for hard and space mouthguard using a glass fiber.

Background/aims: A light-cured intermediate material is useful for fabricating a hard insert and a buffer space mouthguard (H&SMG). However, it requires improvement in its mechanical properties and shock-absorbing capacity. The aim of this study was to evaluate the mechanical properties of two prototype light-cured intermediate materials reinforced with glass fibers, and the impact absorption capacity and durability of H&SMGs made with the prototype intermediate materials.

Effects of Mouthguards on Skin Damage In Vitro Study.

Objective:  Mouthguards can prevent and reduce orofacial sports traumas, which occur to the players themselves. However, the effect of mouthguards on skin damage has not been clarified. The present study's purpose was to examine whether the mouthguard can reduce or prevent skin damage caused by teeth (including the difference in mouthguard thickness).

Neurometabolite Levels and Relevance to Central Sensitization in Chronic Orofacial Pain Patients: A Magnetic Resonance Spectroscopy Study.

Background: Refractory chronic pain in the orofacial region involves central sensitization (CS). However, not all chronic pain patients exhibit CS. An objective assessment of CS may be useful for pain management.

Clinical Statistics of Dysphagia Rehabilitation Provided on Dental Visits to a Partner Hospital.

Maintaining oral hygiene is an important yet often neglected aspect of rehabilitation medicine. Our visiting dental team, which provides dental treatments and swallowing rehabilitation, partnered with a medical hospital that had no dental department and began visiting and treating inpatients at this hospital. This study is aimed at evaluating the effects of dysphagia rehabilitation, and this was jointly conducted by medical and dental hospitals.

Short Tandem Repeat Variation in the Gene Associated With Analgesic Requirements of Opioids in Postoperative Pain Management.

Short tandem repeats (STRs) and variable number of tandem repeats (VNTRs) that have been identified at approximately 0.7 and 0.5 million loci in the human genome, respectively, are highly multi-allelic variations rather than single-nucleotide polymorphisms.

Single-nucleotide polymorphisms of the SLC17A9 and P2RY12 genes are significantly associated with phantom tooth pain.

Phantom tooth pain (PTP) is a rare and specific neuropathic pain that occurs after pulpectomy and tooth extraction, but its cause is not understood. We hypothesized that there is a genetic contribution to PTP. We focused on solute carrier family 17 member 9 (SLC17A9)/vesicular nucleotide transporter (VNUT) and purinergic receptor P2Y12 (P2RY12), both of which have been associated with neuropathic pain and pain transduction signaling in the trigeminal ganglion in rodents.

Silicon nanorod formation from powder feedstock through co-condensation in plasma flash evaporation and its feasibility for lithium-ion batteries.

Si nanowires/nanorods are known to enhance the cycle performance of the lithium-ion batteries. However, viable high throughput production of Si nanomaterials has not yet attained as it requires in general expensive gas source and low-rate and multiple-step approach. As one of the potential approaches, in this work, we report the fast-rate Si nanorod synthesis from low-cost powder source by the modified plasma flash evaporation and the fundamental principle of structural formation during gas co-condensation.