Jaw-neck motor function 2 years after whiplash trauma.

BACKGROUND: There is limited knowledge about the possible long-term effects on jaw motor function after whiplash trauma. OBJECTIVES: The primary aim was to evaluate integrated jaw and head-neck movement amplitudes during jaw function in individuals 2 years after whiplash trauma, compared to controls. The secondary aim was to evaluate changes between the acute stage and a 2-year follow-up in terms of jaw and head-neck movement amplitudes during jaw function. METHODS: This study included 28 cases exposed to a whiplash trauma 2 years earlier (13 women) and 28 controls (13 women) without previous neck trauma. Head and jaw movement amplitudes were recorded during maximal jaw opening-closing movements using an optoelectronic 3D recording system. For a subpopulation of 12 cases and 15 controls, recordings had also been performed in the acute stage after the whiplash trauma. Jaw and head movement amplitudes were analysed using linear regression with group and sex as independent variables. The subpopulation longitudinal analysis was adjusted for movement amplitudes at baseline. RESULTS: Jaw movement amplitudes were significantly associated with group (coefficient: -0.359: 95% CI: -10.70 to -1.93, p = .006) with smaller amplitudes of jaw movements for whiplash cases. Head movement amplitudes were not associated with group (coefficient: -0.051, 95% CI: -4.81 to 3.20, p = .687). In the longitudinal analysis, both jaw and head movement amplitudes showed significant associations between baseline and the 2-year follow-up. CONCLUSION: The present findings indicate that the effects on jaw function in terms of jaw opening capacity in the acute stage after whiplash trauma do not spontaneously recover.

Effects of Integrating Jaw Opening and Closing Movements with Active Neck Exercises in the Management of Chronic Non-Specific Neck Pain: A Randomized Controlled Trial.

Background and Objectives: It has been seen that jaw opening is associated with neck extension and jaw closing is associated with neck flexion. This natural association between the jaw and neck can be used as a novel approach to treat chronic non-specific neck pain, although the effects of this concept have never been previously evaluated as a treatment strategy. This article intends to study the effects of integrating jaw opening and closing movements along with active neck exercises versus active neck exercises alone in the management of chronic non-specific neck pain. Materials and Methods: A total of 80 patients, aged 20 to 50, with chronic non-specific neck pain were included in a double-blind randomized controlled trial, conducted at the Sindh Institute of Physical Medicine and Rehabilitation, Karachi, Pakistan from 2018 to 2022. The patients were divided into two groups: Group A patients were assigned jaw movements with active neck exercises, while Group B patients were assigned only active neck exercises. Both groups were assigned isometric strengthening exercises and self-resisted strengthening exercises for cervical spine muscles as a home plan. The study used various outcome measures, including the numerical pain rating scale (NPRS), neck disability index (NDI), neck flexion endurance (NFE), neck extension endurance (NEE), the neck proprioception error (NPE): neck flexion proprioception error (NFPE), neck extension proprioception error (NEPE), neck right rotation proprioception error (NRRPE), and neck left rotation proprioception error (NLRPE), with measurements taken at week 1 and week 6, respectively; the mean differences between the groups were measured using a two-way repeated ANOVA. Results: The experimental group showed better improvements compared to the control group, NPRS (73%), NDI (57%), NFE (152%), NEE (83%), NFPE (58%), NEPE (65%), NRRPE (65%), and NLRPE (62%), with a significant difference (p < 0.05). Conclusions: Active neck extension and flexion movements combined with jaw opening and closing are more effective in reducing pain and disability, improving neck muscles endurance and normalizing neck proprioception in patients with chronic neck pain.

Association of Oral Behaviors with Anxiety, Depression, and Jaw Function in Patients with Temporomandibular Disorders in China: A Cross-Sectional Study.

BACKGROUND The aim of this study was to investigate the association of oral behaviors (OBs) with anxiety, depression, and jaw function in patients with temporomandibular disorders (TMDs) in China. MATERIAL AND METHODS A total of 537 patients diagnosed with TMD were included in this study (average age, 31.55±12.08 years; 86 men [16.0%] and 451 women [84.0%]). There were 31 cases of masticatory muscle pain, 459 cases of disc displacement, and 13 cases of arthralgia/arthrosis, and 34 cases were uncategorized. Patients were assessed using the Oral Behaviors Checklist (OBC), Jaw Functional Limitation Scale (JFLS), Generalized Anxiety Disorder-7 (GAD-7) scale, and Patient Health Questionnaire-9 (PHQ-9). The relationships between OBC scores and mouth opening, pain scores, JFLS, PHQ-9, and GAD-7 were evaluated with Spearman's correlation analysis. The median TMD symptom duration was 3 (0.5-154) months; men and women did not differ significantly in symptom duration or in the number of episodes of depression and anxiety. RESULTS The following OBs were common in patients with TMDs: "putting pressure on the jaw (52.9%)", "chewing food on 1 side (47.5%)", and "holding teeth together during activities other than eating (33.3%)". The OBC scores were significantly correlated with the JFLS, PHQ-9, and GAD-7 scores (P<0.01). CONCLUSIONS Patients with TMDs exhibit specific OBs, which are associated with depression, anxiety, and jaw function. It is necessary to further investigate the interaction of OBs with depression and anxiety in the development of TMDs.

Circuit-Specific Early Impairment of Proprioceptive Sensory Neurons in the SOD1G93A Mouse Model for ALS.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease in which motor neurons degenerate, resulting in muscle atrophy, paralysis, and fatality. Studies using mouse models of ALS indicate a protracted period of disease development with progressive motor neuron pathology, evident as early as embryonic and postnatal stages. Key missing information includes concomitant alterations in the sensorimotor circuit essential for normal development and function of the neuromuscular system. Leveraging unique brainstem circuitry, we show in vitro evidence for reflex circuit-specific postnatal abnormalities in the jaw proprioceptive sensory neurons in the well-studied SOD1G93A mouse. These include impaired and arrhythmic action potential burst discharge associated with a deficit in Nav1.6 Na+ channels. However, the mechanoreceptive and nociceptive trigeminal ganglion neurons and the visual sensory retinal ganglion neurons were resistant to excitability changes in age-matched SOD1G93A mice. Computational modeling of the observed disruption in sensory patterns predicted asynchronous self-sustained motor neuron discharge suggestive of imminent reflexive defects, such as muscle fasciculations in ALS. These results demonstrate a novel reflex circuit-specific proprioceptive sensory abnormality in ALS.SIGNIFICANCE STATEMENT Neurodegenerative diseases have prolonged periods of disease development and progression. Identifying early markers of vulnerability can therefore help devise better diagnostic and treatment strategies. In this study, we examined postnatal abnormalities in the electrical excitability of muscle spindle afferent proprioceptive neurons in the well-studied SOD1G93A mouse model for neurodegenerative motor neuron disease, amyotrophic lateral sclerosis. Our findings suggest that these proprioceptive sensory neurons are exclusively afflicted early in the disease process relative to sensory neurons of other modalities. Moreover, they presented Nav1.6 Na+ channel deficiency, which contributed to arrhythmic burst discharge. Such sensory arrhythmia could initiate reflexive defects, such as muscle fasciculations in amyotrophic lateral sclerosis, as suggested by our computational model.

Floppy epiglottis during drug-induced sleep endoscopy: an almost complete resolution by adopting the lateral posture.

PURPOSE: To analyze the presence of a floppy epiglottis (FE) during drug-induced sleep endoscopy in non-apneic snoring patients, non-positional obstructive sleep apnea (OSA) patients (NPP), and position-dependent OSA patients (PP) and to evaluate the impact of maneuvers and body position during drug-induced sleep endoscopy, including jaw thrust and supine and lateral head (and trunk) position. METHODS: Retrospective cohort study. RESULTS: In total, 324 patients were included. In 60 patients (18.5%), a FE was found in supine position: seven non-apneic snoring patients and 53 OSA patients. When performing lateral head rotation only, a FE was present in four patients (NPP, N = 0; PP, N = 4). When patients were tilted to both lateral head and trunk position, a FE was found in only one subject. After applying jaw thrust, a FE was still present in 10 patients. The prevalence of a FE did not differ between NPP and PP. When comparing baseline characteristics between patients with and without a FE in supine position, no significant differences were found. CONCLUSION: A FE appears almost exclusively in supine position. In patients with a FE, positional therapy can be a promising alternative as a standalone treatment, but also as part of combination therapy with for example mandibular advancement devices or less invasive forms of upper airway surgery.

The effect of brief pre-anesthetic exercise therapy of jaw and neck joints on mouth opening, neck extension, and intubation conditions during induction of general anesthesia: a randomized controlled trial.

BACKGROUND: The effort to improve tracheal intubation process is clinically valuable. We hypothesized that a preoperative brief exercise therapy would increase mouth opening and neck extension, enhancing intubation conditions during general anesthesia. METHODS: Patients undergoing general anesthesia were randomized into two groups. The exercise group performed the exercise regimen including masseter muscle massage and stretching of jaw and neck joints before anesthetic induction, while the control did not. Before (baseline) and after the intervention, we evaluated Mallampati score, mouth aperture size, and sternomental distance. After tracheal intubation, intubation difficulty scale with direct laryngoscope and oropharyngeal soft tissue injury were also evaluated. RESULTS: A total of 138 patients completed the analysis (control = 68, exercise = 70). Baseline characteristics did not differ between groups. At anesthetic induction, there was a significant difference in Mallampati score between the two groups (P = 0.039) and the incidence of Mallampati scores of 1 was higher in the exercise group (odds ratio [95% CI]: 2.1 [1.0-4.3], P = 0.043). Mouth opening after the intervention was greater in the exercise group than in the control group (estimated difference [95% CI]: - 2.4 [- 4.8 - -0.1], P = 0.042) and sternomental distance was similar between the two groups (estimated difference [95% CI]: - 3.7 [- 9.0-1.7, P = 0.175). The exercise group showed less soft tissue injuries (odds ratio [95% CI]: 0.2 [0.1-0.8], P = 0.009), however, intubation difficulty scale did not differ between the study groups (P = 0.112). CONCLUSIONS: The brief pre-anesthetic exercise improved intubation conditions and enabled faster tracheal intubation with less injury to oropharyngeal soft tissue. TRIAL REGISTRATION: Clinical Research Information Service (registration number: KCT0002618), registered at December 28, 2017.

Experimentally induced rhythmic jaw muscle activities during non-rapid eye movement sleep in freely moving guinea pigs.

Rhythmic jaw muscle activities frequently occur during non-rapid eye movement sleep in patients with sleep bruxism. The present study aimed to investigate the response characteristics of the masticatory rhythm generation during non-rapid eye movement sleep in animals. Eleven guinea pigs were surgically prepared for polygraphic recordings by electromyography, electrooculography, electroencephalography and electrocardiography with the implantation of a stimulating electrode. Repetitive electrical microstimulations at three intensities were applied to the corticobulbar tract under freely moving conditions. The rhythmic electro-myographic responses of the digastric and masseter muscles were scored and analysed. Changes in cortical electro-encephalographic power and heart rate in association with these stimulations were quantified. Microstimulations to the corticobulbar tract induced rhythmic jaw muscle activities in digastric muscles, occasionally with masseter activities during wakefulness and non-rapid eye movement sleep. The response rate of rhythmic jaw muscle activities was significantly lower (p < 0.01) and the response latency was significantly longer (p < 0.01) during non-rapid eye movement sleep than during wakefulness. At higher stimulus intensities, the response rate increased and response latency decreased. The mean burst intervals of the digastric and masseter muscles were similar regardless of vigilance states and stimulus intensities. Induced rhythmic jaw muscle activities during non-rapid eye movement sleep were followed by a transient decrease in delta power and increases in beta power and heart rate. During non-rapid eye movement sleep, the masticatory motor system is able to generate rhythmic outputs to the jaw muscles in response to facilitatory inputs although the responsiveness was decreased from wakefulness.

Characterizing the Motor Skills in Children with Specific Language Impairment.

BACKGROUND/AIMS: Specific language impairment (SLI) is characterized by deficits in language ability. However, studies have also reported motor impairments in SLI. It has been proposed that the language and motor impairments in SLI share common origins. This exploratory study compared the gross, fine, oral, and speech motor skills of children with SLI and children with typical development (TD) to determine whether children with SLI would exhibit difficulties on particular motor tasks and to inform us about the underlying cognitive deficits in SLI. METHODS: A total of 13 children with SLI (aged 8-12 years) and 14 age-matched children with TD were administered the Movement Assessment Battery for Children - Second Edition and the Verbal Motor Production Assessment for Children to examine gross and fine motor skills and oral and speech motor skills, respectively. RESULTS: Children with SLI scored significantly lower on gross, fine, and speech motor tasks relative to children with TD. In particular, children with SLI found movements organized into sequences and movement modifications challenging. On oral motor tasks, however, children with SLI were comparable to children with TD. CONCLUSION: Impairment of the motor sequencing and adaptation processes may explain the performance of children with SLI on these tasks, which may be suggestive of a procedural memory deficit in SLI.

Orofacial Manifestations and Temporomandibular Disorders of Sjögren Syndrome: An Observational Study.

AIMS: SjÓ§gren Syndrome is a disorder involving oral tissues, with xerostomia, dysgeusia, dysphagia, tooth decay, gingivitis, angular cheilitis and glossitis. Temporomandibular disorders are a generic term referred to clinical conditions involving the jaw muscles and temporomandibular joint. The aim of this study was to investigate the prevalence of oral manifestations and temporomandibular disorders (TMD) in SjÓ§gren Syndrome (SS) patients compared with healthy people. METHODS: The study group included 72 SS patients (2 men, 70 women) diagnosed according to the American-European Consensus Group (AECG) Criteria. A randomly selected group of 72 patients, matched by sex and age, served as control group. The examination for TMD signs and symptoms was based on the standardized Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) through a questionnaire and clinical examination. RESULTS: SS patients complained more frequently (95.8%) of oral symptoms (xerostomia, dysgeusia, dysphagia) than controls (22.2%) (χ2= 80.66 p< 0.001). TMD symptoms (muscle pain on chewing, difficulty in mouth opening, arthralgia, headaches, tinnitus) were complained by 91.7% of SS patients and by 84.7% of controls (χ2= 1,667 p= 0,196). At the clinical examination, 91,7% of SS had at least one oral sign respect to 75 % of controls. The salivary flow measurements showed high statistical significance between the two groups (Unpaired test, p< 0,0001). Myofascial pain (caused by muscular contracture) was significantly higher in the study group than in the control one (p≤ 0,05). Furthermore 18,05% of SS patients showed deflection versus 5,5% of controls (χ2=5,402 p=0,020). CONCLUSIONS: SjÓ§gren's Syndrome seems to play a role in temporomandibular joint disorders.

Lingual and Jaw Kinematic Abnormalities Precede Speech and Swallowing Impairments in ALS.

Early identification of bulbar involvement in persons with ALS is critical for improving diagnosis and prognosis; however, efficacious diagnostic markers have not yet been identified. The purpose of this study was to determine whether kinematic changes of the tongue and jaw during swallowing, measured using 3D electromagnetic articulography (EMA), predate clinically identifiable symptoms of speech and swallowing impairment in persons diagnosed with ALS. Data were collected from 16 adults diagnosed with ALS and 18 neurotypical controls. Groups were aged matched. Eligible participants with ALS were tolerating an unrestricted diet (FOIS = 7), produced intelligible speech (> 97%), and had a speaking rate greater than 150 words per minute. Participants completed a 3-mL water swallow task, during which EMA recorded kinematic measures of the anterior and posterior regions of tongue including lingual speed, range of motion, duration, coordination, and efficiency. Jaw speed and range of motion were also recorded. Persons diagnosed with ALS demonstrated reduced posterior lingual range of motion (11.40 mm ± 4.01 vs. 16.07 mm ± 5.27), slower posterior lingual speeds (83.67 mm/s ± 47.96 vs. 141.35 mm/s ± 66.54), increased lingual movement duration (13.46 s ± 6.75 vs. 9.21 s ± 3.28), and reduced lingual coordination (0.04 s ± 0.11 vs. 17 s ± 0.19) during the 3-oz water swallow task compared to controls. Persons diagnosed with ALS demonstrated increased range of motion (9.86 mm ± 5.38 vs. 6 mm ± 3.78) and increased jaw speed (68.62 mm/s ± 50.13 vs. 34.72 mm/s ± 17.75) during swallowing compared to controls. The current findings suggest that changes in lingual and jaw motor performance during a simple water swallow task are present in persons with ALS who are pre-symptomatic of clinically detectable bulbar impairment.

Complete dentures for a patient after a stroke by means of orofacial myofunctional therapy: A clinical report.

After a stroke, patients frequently show compromised swallowing, mastication, and speech, as well as unfavorable motion and deviation of the tongue and mandible. The dentist can improve the oral rehabilitation of a patient with deteriorated facial and oral muscles after a stroke by incorporating orofacial myofunctional therapy. This report describes a method for tongue exercises and correction of mandible deviation in an edentulous patient after a stroke by using a pearl on a wire in the anteriomedian palatal part of the maxillary denture.

Orthodontic treatment-induced temporal alteration of jaw-opening reflex excitability.

The impairment of orofacial motor function during orthodontic treatment needs to be addressed, because most orthodontic patients experience pain and motor excitability would be affected by pain. In the present study, the temporal alteration of the jaw-opening reflex excitability was investigated to determine if orthodontic treatment affects orofacial motor function. The excitability of jaw-opening reflex evoked by electrical stimulation on the gingiva and recorded bilaterally in the anterior digastric muscles was evaluated at 1 (D1), 3 (D3), and 7 days (D7) after orthodontic force application to the teeth of right side; morphological features (e.g., osteoclast genesis and tooth movement) were also evaluated. To clarify the underlying mechanism of orthodontic treatment-induced alteration of orofacial motor excitability, analgesics were administrated for 1 day. At D1 and D3, orthodontic treatment significantly decreased the threshold for inducing the jaw-opening reflex but significantly increased the threshold at D7. Other parameters of the jaw-opening reflex were also evaluated (e.g., latency, duration and area under the curve of anterior digastric muscles activity), and only the latency of the D1 group was significantly different from that of the other groups. Temporal alteration of the jaw-opening reflex excitability was significantly correlated with changes in morphological features. Aspirin (300 mg·kg-1·day-1) significantly increased the threshold for inducing the jaw-opening reflex, whereas a lower dose (75-150 mg·kg-1·day-1) of aspirin or acetaminophen (300 mg·kg-1·day-1) failed to alter the jaw-opening reflex excitability. These results suggest that an increase of the jaw-opening reflex excitability can be induced acutely by orthodontic treatment, possibly through the cyclooxygenase activation.NEW & NOTEWORTHY It is well known that motor function is affected by pain, but the effect of orthodontic treatment-related pain on the trigeminal motor excitability has not been fully understood. We found that, during orthodontic treatment, trigeminal motor excitability is acutely increased and then decreased in a week. Because alteration of trigeminal motor function can be evaluated quantitatively by jaw-opening reflex excitability, the present animal model may be useful to search for alternative approaches to attenuate orthodontic pain.

A peculiar mechanism of bite-force enhancement in lungless salamanders revealed by a new geometric method for modeling muscle moments.

Desmognathine salamanders possess unusual morphological features for lungless salamanders that have been proposed to aid in burrowing and biting, including well-ossified jaws and skull and a pair of robust ligaments connecting the atlas to the mandible. We evaluated the function of these and other peculiar desmognathine cranial features in biting by examining the morphology, mechanics and in vivo biting performance of the large Desmognathus quadramaculatus We estimated theoretical biting force using a novel geometric method that we describe. Results provide quantitative evidence to bolster earlier conclusions that the unusual atlanto-mandibular ligaments couple ventral head flexion, a unique desmognathine behavior, with biting performance. Our analysis also reveals that the ligaments not only transmit, but also amplify the force of head flexion when acting together with the unusual stalked occipital condyles, enlarged atlas and massive quadratopectoralis muscles. The geometric model predicts that this mechanism contributes five times the biting force of the three jaw levator muscles combined and predicts that maximum biting force in D. quadramaculatus matches or exceeds forces reported for similarly sized lizards. The in vivo biting performance we measured was several times greater in D. quadramaculatus than another plethodontid salamander, Pseudotriton ruber, which lacks the unusual morphology and mechanism of desmognathines. The effective biting mechanism of D. quadramaculatus we describe is an emergent property of many of the distinguishing morphological features of desmognathine salamanders and likely plays an important role in their natural history given that desmognathines use biting in feeding, defense and even courtship.

Association between patterns of jaw motor activity during sleep and clinical signs and symptoms of sleep bruxism.

The aim of this study was to investigate the association between patterns of jaw motor activity during sleep and clinical signs and symptoms of sleep bruxism. A total of 35 university students and staff members participated in this study after providing informed consent. All participants were divided into either a sleep bruxism group (n = 21) or a control group (n = 14), based on the following clinical diagnostic criteria: (1) reports of tooth-grinding sounds for at least two nights a week during the preceding 6 months by their sleep partner; (2) presence of tooth attrition with exposed dentin; (3) reports of morning masticatory muscle fatigue or tenderness; and (4) presence of masseter muscle hypertrophy. Video-polysomnography was performed in the sleep laboratory for two nights. Sleep bruxism episodes were measured using masseter electromyography, visually inspected and then categorized into phasic or tonic episodes. Phasic episodes were categorized further into episodes with or without grinding sounds as evaluated by audio signals. Sleep bruxism subjects with reported grinding sounds had a significantly higher total number of phasic episodes with grinding sounds than subjects without reported grinding sounds or controls (Kruskal-Wallis/Steel-Dwass tests; P < 0.05). Similarly, sleep bruxism subjects with tooth attrition exhibited significantly longer phasic burst durations than those without or controls (Kruskal-Wallis/Steel-Dwass tests; P < 0.05). Furthermore, sleep bruxism subjects with morning masticatory muscle fatigue or tenderness exhibited significantly longer tonic burst durations than those without or controls (Kruskal-Wallis/Steel-Dwass tests; P < 0.05). These results suggest that each clinical sign and symptom of sleep bruxism represents different aspects of jaw motor activity during sleep.

Test-retest reliability of quantitative sensory testing for mechanical somatosensory and pain modulation assessment of masticatory structures.

Assessing the reliability of medical measurements is a crucial step towards the elaboration of an applicable clinical instrument. There are few studies that evaluate the reliability of somatosensory assessment and pain modulation of masticatory structures. This study estimated the test-retest reliability, that is over time, of the mechanical somatosensory assessment of anterior temporalis, masseter and temporomandibular joint (TMJ) and the conditioned pain modulation (CPM) using the anterior temporalis as the test site. Twenty healthy women were evaluated in two sessions (1 week apart) by the same examiner. Mechanical detection threshold (MDT), mechanical pain threshold (MPT), wind-up ratio (WUR) and pressure pain threshold (PPT) were assessed on the skin overlying the anterior temporalis, masseter and TMJ of the dominant side. CPM was tested by comparing PPT before and during the hand immersion in a hot water bath. anova and intra-class correlation coefficients (ICCs) were applied to the data (α = 5%). The overall ICCs showed acceptable values for the test-retest reliability of mechanical somatosensory assessment of masticatory structures. The ICC values of 75% of all quantitative sensory measurements were considered fair to excellent (fair = 8·4%, good = 33·3% and excellent = 33·3%). However, the CPM paradigm presented poor reliability (ICC = 0·25). The mechanical somatosensory assessment of the masticatory structures, but not the proposed CPM protocol, can be considered sufficiently reliable over time to evaluate the trigeminal sensory function.

Exercise intervention for the treatment of trismus in head and neck cancer - a prospective two-year follow-up study.

Background This study aims to investigate the long-term effects of structured trismus intervention in patients with head and neck cancer (HNC) and trismus in terms of mouth opening, trismus-related symptoms and health-related quality of life (HRQL). Material and methods Fifty patients with HNC to receive radiotherapy ± chemotherapy were included in this prospective study along with a matched control group. The intervention group received a 10-week structured exercise with a jaw mobilizing device (TheraBite® jaw device or Engström device). Patients were assessed before and after trismus exercise intervention and at a two-year follow-up. Primary endpoint was maximum interincisal opening (MIO) and secondary endpoints included trismus-related symptoms and HRQL assessed with patient-reported outcome (PRO)-instruments [Gothenburg Trismus Questionnaire (GTQ), European Organization for Research and Treatment of Cancer Core Questionnaire (EORTC QLQ-C30) and the related HNC-specific module the EORTC Head & Neck Questionnaire (EORTC QLQ-H&N35)]. Results The intervention group had a higher MIO at the two-year follow-up compared to the control group (40.5 mm and 34.3 mm, respectively), which was statistically significant. The intervention group also reported less jaw-related problems according to the GTQ and higher functioning as measured by EORTC QLQ-C30 and QLQ-H&N35 compared to the control group. Conclusion A positive persistent effect of exercise intervention for trismus in HNC patients was found with regard to MIO, trismus-related symptoms and HRQL. Exercise intervention is important in long-term treatment of radiation-induced trismus in HNC patients. The trismus-specific questionnaire, GTQ, is a valuable tool for observing and evaluating trismus over time.

Altered neural activation pattern during teeth clenching in temporomandibular disorders.

OBJECTIVE: The aim was to explore the neural activations during teeth clenching in TMDs patients pre- and post-treatment. SUBJECTS AND METHODS: Thirty TMDs patients and 20 controls underwent clinical evaluations and functional magnetic resonance imaging with a teeth clenching task. Eleven patients received repeat evaluation and imaging after wearing a stabilization splint for 3 months. RESULTS: During teeth clench, the TMDs patients showed decreased positive activity in the left precentral gyrus, right and left inferior temporal gyrus, and left cerebellum and increased negative activations in the right medial prefrontal cortex (P < 0.05 after AlphaSim correction). The 11 TMDs patients after treatment showed a return to normal neural activity in these areas. No brain areas in TMDs patients showed differences in activation after treatment compared with the controls, except for an increase in activation in the right cerebellum in the 11 TMDs patients (P < 0.05 after AlphaSim correction). CONCLUSION: Decreased activations in cerebral areas associated with motor and cognitive functions in TMDs patients during teeth clenching were observed. Normalized activations of these areas happened in patients after routine treatment. These findings may facilitate the understanding of TMDs pathogenesis and the therapeutic mechanisms of the stabilization splint.

Validation of Clinical Observations of Mastication in Persons with ALS.

Amyotrophic lateral sclerosis (ALS) is a progressive neurological disease that can result in difficulties with mastication leading to malnutrition, choking or aspiration, and reduced quality of life. When evaluating mastication, clinicians primarily observe spatial and temporal aspects of jaw motion. The reliability and validity of clinical observations for detecting jaw movement abnormalities is unknown. The purpose of this study is to determine the reliability and validity of clinician-based ratings of chewing performance in neuro-typical controls and persons with varying degrees of chewing impairments due to ALS. Adults chewed a solid food consistency while full-face video were recorded along with jaw kinematic data using a 3D optical motion capture system. Five experienced speech-language pathologists watched the videos and rated the spatial and temporal aspects of chewing performance. The jaw kinematic data served as the gold-standard for validating the clinicians' ratings. Results showed that the clinician-based rating of temporal aspects of chewing performance had strong inter-rater reliability and correlated well with comparable kinematic measures. In contrast, the reliability of rating the spatial and spatiotemporal aspects of chewing (i.e., range of motion of the jaw, consistency of the chewing pattern) was mixed. Specifically, ratings of range of motion were at best only moderately reliable. Ratings of chewing movement consistency were reliable but only weakly correlated with comparable measures of jaw kinematics. These findings suggest that clinician ratings of temporal aspects of chewing are appropriate for clinical use, whereas ratings of the spatial and spatiotemporal aspects of chewing may not be reliable or valid.

Headache and jaw locking comorbidity with daytime sleepiness.

PURPOSE: To investigate the relationship between craniofacial pain symptoms (painful conditions present in the cranium and face, including jaw joint-related pathology and primary headache conditions) and daytime sleepiness, determined by the Epworth sleepiness scale (ESS), to correlate comorbidity as well as potential predictive factors. METHODS: 1,171 patients seeking care for chronic pain and/or sleep-related breathing disorders (SRBDs) at 11 international treatment centers were included in the study. Patients completed the ESS and identified their primary craniofacial pain and sleep pathology symptoms. Descriptive statistics and regression analysis were performed to determine comorbidities between craniofacial pain symptoms and daytime sleepiness, and factors predictive of higher ESS scores. RESULTS: There was high comorbidity of some craniofacial pain symptoms and high ESS scores, including headaches. In addition, for the first time to our knowledge, orthopedic craniofacial dysfunction (i.e., jaw locking) was correlated with, and predictive of, high ESS scores.