Reliability of an intraoral extension for intraoral palpation and assessment of mechanical sensitivity of the temporal tendon.

BACKGROUND: The temporal tendon is a structure often compromised in patients suffering from temporomandibular disorders (TMD), yet its intraoral location makes a standardised assessment difficult. OBJECTIVES: To evaluate the variability and accuracy to target force of a newly designed intraoral extension for a palpometer device (Palpeter, Sunstar Suisse) when compared to manual palpation, in addition to clinically assessing the mechanical sensitivity and referred sensations of the temporal tendon in healthy individuals. METHODS: Experiment 1: 12 individuals were asked to target on a scale 0.5, 1 and 2 kg, for 2 and 5 s by using five different methods (Palpeter, Palpeter with three different extension shapes and manual palpation). Experiment 2: 10 healthy participants were recruited for a randomised double-blinded assessment by applying pressure of 0.5, 1 and 2 kg to the right temporal tendon with the three extensions and manual palpation. Participants rated the intensity of their sensation/pain on a 0-50-100 numeric rating scale (NRS), unpleasantness on a 0-100 NRS, and if present, they rated and drew the location of referred sensations. Repeated measures analysis of variance (ANOVA) was used in both experiments to compare differences between palpation methods. Tukey's HSD tests were used for the post hoc comparisons, and p values below .05 were considered significant. RESULTS: Experiment 1: The extensions showed no significant differences between them regarding reliability and accuracy for all forces and durations (p > .05). The manual method was significantly less reliable and accurate when compared to the other methods (p < .05). Experiment 2: There were no significant differences between the Palpeter extensions regarding pain intensity or unpleasantness NRS scores (p > .05), but all the extensions had significantly increased pain intensity and unpleasantness when compared to manual palpation (p < .05). Similarly, the frequency of referred sensations was similar between extensions but increased when compared to manual palpation. CONCLUSIONS: The new Palpeter extensions proved to be significantly more accurate and have lower test-retest variability than the manual method in a non-clinical setting. Clinically, they showed no significant differences in NRS scores for pain intensity nor unpleasantness, with no major differences in referred sensations, making any of the extensions suitable for clinical testing of the temporal tendon in future studies.

Comparison of force profiles from two musculoskeletal palpation methods: A methodological study.

BACKGROUND: The Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) protocol recommends a 5 s and 1 kg force dynamic palpation around the lateral condylar pole of the temporomandibular joint. However, the accuracy and precision of the generated force are not known. OBJECTIVE: To assess and compare the force profiles generated from dynamic palpation manually and using a palpometer, based on the forces and time recommendations suggested by the DC/TMD protocol. METHODS: Nineteen healthy adults applied forces of 0.5 kg, 1.0 kg and 2.0 kg on a calibrated force sensor in a circular motion within target times of 2 s and 5 s. Participants used their right index finger for manual palpation and a calibrated palpometer for device-assisted palpation. Ten repetitions of each target force at both target times were applied. Time taken to complete each application was recorded. Repeated measures analysis of variance was used for analysis of accuracy measured as the relative difference between targeted force and actual force values and precision measured as the coefficient of variation (CV) within the 10 repeated measurements. RESULTS: Accuracy was significantly lower (better) and precision higher (lower CV) with the palpometer than with manual palpation (p < .001). There were significant differences in accuracy and precision between the different forces but not palpation times. Most participants could not achieve the target times and tended to be faster, irrespective of the palpation method (p > .063). CONCLUSION: A palpometer is a more accurate and precise palpation method for dynamic force assessment compared to manual palpation; however, it remains difficult to standardize the palpation duration.

Correlations between sleep architecture and sleep-related masseter muscle activity in children with sleep bruxism.

BACKGROUND: Sleep bruxism (SB) occurring during No-REM (nREM) sleep and increase in microarousals per hour have been described in adults, but not in children. OBJECTIVE: To assess the correlation between sleep architecture and masseter muscle activity related to sleep bruxism (SB/MMA) in children. MATERIALS AND METHODS: Forty-three children aged 7-12 years (mean age: 9.4 ± 1.3) with confirmed SB underwent a two-night polysomnographic (PSG) study in a sleep laboratory, for accommodation (first night) and data collection (second night). Data on sleep architecture (total sleep duration (TSD), sleep efficiency (SE), sleep onset latency (SOL), REM and nREM sleep duration and proportion and microarousals/hour during REM and nREM sleep) and episodes/hour of SB/MMA were recorded. Single and multiple-variable linear regression analyses were performed to assess the correlation between data on sleep architecture (predictors) and SB/MMA (dependent variable). RESULTS: Shorter TSD, REM and nREM stage 1 sleep duration, longer SOL and more microarousals/hour during REM and nREM sleep were found to be positive predictors of SB/MMA in children in the multiple-variable regression analysis (R2  = 0.511). CONCLUSION: Within the limitations of this study, it can be concluded that SB/MMA is correlated with altered sleep architecture in children (shorter total sleep duration (TSD), shorter nREM and REM sleep and higher microarousals during REM and nREM sleep). Nevertheless, the clinical significance of these findings need to be demonstrated in future studies.

Estrés académico asociado a proteína C-reactiva y síndrome metabólico en estudiantes de medicina / Academic stress associated with C - reactive protein and metabolic syndrome in medical students

Introducción: El estrés académico resulta de la confrontación de un individuo con las demandas del medio universitario, lo cual puede producir cambios a nivel neuro-endocrino-inmunológico y generar un estado de inflamación crónica en donde los niveles de proteína C-reactiva aumentan. Objetivo: Determinar los niveles de estrés académico y proteína C-reactiva en estudiantes de medicina y su posible asociación con síndrome metabólico. Métodos: Se realizó un estudio observacional descriptivo de corte longitudinal que determinó el estrés académico en 68 estudiantes de medicina (41 mujeres y 27 hombres). Se obtuvo información sociodemográfica y clínica de cada estudiante. Se aplicó un cuestionario para la evaluación del estrés académico y se obtuvieron dos muestras de sangre para realizar dos pruebas de proteína C-reactiva de alta sensibilidad en dos tiempos diferentes. Resultados: Pese a que se observaron niveles altos de estrés académico y proteína C-reactiva, no hubo una asociación directa; sin embargo, se encontraron relaciones significativas entre proteína C-reactiva y las variables clínicas, además de un riesgo alto de desarrollar síndrome metabólico. Conclusiones: Se observaron altos niveles de estrés académico asociado a las demandas y exigencias de un programa de medicina con acreditación de alta calidad. Los altos niveles de proteína C-reactiva fueron asociados a los altos niveles de obesidad abdominal, lo que hace que un número significativo de estudiantes se encuentre en riesgo de desarrollar enfermedades cardiovasculares y diabetes mellitus tipo 2, sobre todo aquellos en los que se detectó prehipertensión. No se encontró una relación significativa entre el estrés académico y los niveles de proteína C-reactiva(AU)

Introduction: Academic stress results from the confrontation of an individual with the demands of the university environment, which can produce changes at the neuro-endocrine-immunological level and generate a state of chronic inflammation where the levels of C-reactive protein increase. Objective: To determine the levels of academic stress and C-reactive protein in medical students and their possible association with metabolic syndrome. Methods: A longitudinal descriptive observational study was conducted to determine academic stress in 68 medical students (41 women and 27 men). Sociodemographic and clinical information was obtained from each student. A questionnaire was applied to assess academic stress and two blood samples were obtained to perform two high-sensitivity C-reactive protein tests at two different times. Results: Although high levels of academic stress and C-reactive protein were observed, there was no direct association; however, significant relationships were found between C-reactive protein and clinical variables, in addition to a high risk of developing metabolic syndrome. Conclusions: High levels of academic stress associated with the demands and requirements of a medicine program with high quality accreditation were observed. High levels of C-reactive protein were associated with high levels of abdominal obesity, which means that a significant number of students are at risk of developing cardiovascular diseases and type 2 diabetes mellitus, especially those in whom prehypertension was detected. No significant relationship was found between academic stress and C-reactive protein levels(AU)

Estado de salud oral de pacientes hospitalizados con trastornos mentales: Revisión sistemática de la literatura / Oral Health Status of Hospitalized Patients with Mental Disorders: Systematic Review of the Literature

RESUMEN De acuerdo a la literatura, los pacientes hospitalizados con trastornos mentales (TM), tienen mayor riesgo a desarrollar caries y enfermedad periodontal que la población general, asociado a la dificultad motora para hacerse una adecuada higiene oral, a los efectos adversos que ocasionan los medicamentos para el control de los síntomas psiquiátricos y a la falta de cuidado oral y atención clínica. El objetivo era realizar una revisión sistemática de la literatura sobre el estado de salud oral de pacientes hospitalizados con TM. Se hizo una búsqueda sistemática de la literatura en PubMed, de acuerdo con la metodología de la declaración PRISMA, a través de los descriptores en salud MeSh "Dental Caries" y "Mental Disorders" a febrero de 2017. De acuerdo a los diferentes filtros que fueron aplicados, se obtuvieron 14 artículos que describieron el estado de salud oral -mediante el índice COP-D (dientes con caries, dientes con restauraciones, dientes perdidos y dientes con extracción mandatoria)- de pacientes hospitalizados con TM. Se debe promover el reconocimiento de la importancia de la salud oral por parte de los profesionales de la salud, cuidadores y familiares; se debe explorar la cavidad oral para determinar el estado de salud además de instruir a los pacientes y personal de apoyo en higiene oral; las instituciones de salud mental deben establecer un programa de intervención para eliminar focos infecciosos orales y luego implementar un programa preventivo multidisciplinario para mantener la salud oral de acuerdo al diagnóstico del TM.

ABSTRACT According to the literature, hospitalized patients with mental disorders have a higher risk of developing cavities and periodontal disease than the general population, associated with the motor difficulty to perform adequate oral hygiene, to the adverse effects caused by drugs for the control of psychiatric symptoms, as well as the lack of oral care and clinical care. The aim was to carry out a systematic review of the literature on the oral health status of hospitalized patients with mental disorders (MD). A systematic search of the literature was carried out in PubMed, according to the PRISMA statement methodology, through the MeSh health descriptors "Dental Caries" and "Mental Disorders" in February 2017. According to the different filters that were applied, 14 articles describing the oral health status were obtained - through the DMF-T index (teeth with cavities, teeth with restorations, missing teeth and teeth with necessary extraction)- of hospitalized patients with MD. The recognition of the importance of oral health by health professionals, carers and family members should be promoted; the oral cavity should be explored to determine the state of health in addition to instructing patients and support personnel in oral hygiene; mental health institutions should establish an intervention programme to eliminate oral infectious sites and then implement a multidisciplinary preventive programme to maintain oral health according to the MD diagnosis.

Oral health status of hospitalised patients with mental disorders: Systematic review of the literature.

According to the literature, hospitalised patients with mental disorders have a higher risk of developing cavities and periodontal disease than the general population, associated with the motor difficulty to perform adequate oral hygiene, to the adverse effects caused by drugs for the control of psychiatric symptoms, as well as the lack of oral care and clinical care. The aim was to carry out a systematic review of the literature on the oral health status of hospitalised patients with mental disorders (MD). A systematic search of the literature was carried out in PubMed, according to the PRISMA statement methodology, through the MeSh health descriptors "Dental Caries" and "Mental Disorders" in February 2017. According to the different filters that were applied, 14 articles describing the oral health status were obtained-through the DMF-T index (teeth with cavities, teeth with restorations, missing teeth and teeth with necessary extraction)-of hospitalised patients with MD. The recognition of the importance of oral health by health professionals, carers and family members should be promoted; the oral cavity should be explored to determine the state of health in addition to instructing patients and support personnel in oral hygiene; mental health institutions should establish an intervention programme to eliminate oral infectious sites and then implement a multidisciplinary preventive programme to maintain oral health according to the MD diagnosis.

Remote physical examination for temporomandibular disorders.

ABSTRACT: There is a need to further develop telemedicine approaches because of the immediate and perhaps long-term consequences of the coronavirus disease 2019. Thus, a remote protocol for assessment of patients with temporomandibular disorders (TMD) was developed, and the agreement of this protocol was compared with the guidelines of the Diagnostic Criteria for TMD (DC/TMD). A total of 16 individuals were first assessed by a reference standard examination (RSE) and 3 other examinations applied in a random order by 3 examiners: standard physical examination (standard examination), physical examination keeping 2-m distance (physical distanced examination), and examination conducted with the aid of video communication technology (video communication examination). The primary outcomes were the diagnoses of myalgia of the masseter and temporalis muscles and arthralgia. The diagnoses of intra-articular joint disorders were considered secondary outcomes because of a less impact on psychosocial functioning and quality of life when compared with the pain-related diagnoses. The Fleiss kappa coefficient and its 95% confidence interval were computed to determine the level of agreement in diagnoses between each examination protocol and the RSE. There was substantial to almost perfect agreement between the RSE and all the examination protocols for the diagnoses of myalgia (0.86-1.00) and arthralgia (0.74-0.87) (P < 0.001). On the other hand, there was an overall poor agreement (0.30-0.58) between the RSE and all the protocols for the diagnosis of disk displacement with reduction. Remote assessment of patients with pain-related TMD is feasible and presents a high degree of accuracy.

Effect of mandibular advancement device on plasticity in corticomotor control of tongue and jaw muscles.

STUDY OBJECTIVES: This study aims to investigate whether the use of a mandibular advancement device (MAD) is associated with neuroplasticity in corticomotor control of tongue and jaw muscles. METHODS: Eighteen healthy individuals participated in a randomized crossover study with 3 conditions for 2 weeks each: baseline, wearing an oral appliance (sham MAD), or MAD during sleep. The custom-made MAD was constructed by positioning the mandible to 50% of its maximal protrusion limit. Transcranial magnetic stimulation was applied to elicit motor-evoked potentials (MEPs). The MEPs were assessed by constructing stimulus-response curves at 4 stimulus intensities: 90%, 100%, 120%, and 160% of the motor threshold from the right tongue and right masseter and the first dorsal interosseous muscles (control) at baseline, after the first and the second intervention. RESULTS: There was a significant effect of condition and stimulus intensity both on the tongue and on masseter MEPs (P < .01). Tongue and masseter MEPs were significantly higher at 120% and 160% after the MAD compared with the oral appliance (P < .05). There were no effects of condition on first dorsal interosseous muscle MEPs (P = .855). CONCLUSIONS: The finding suggests that MAD induces neuroplasticity in the corticomotor pathway of the tongue and jaw muscles associated with the new jaw position. Further investigations are required in patients with obstructive sleep apnea to see whether this cortical neuroplasticity may contribute or perhaps predict treatment effects with MADs in obstructive sleep apnea. CITATION: Matsuzaki S, Shimada A, Tanaka J, et al. Effect of mandibular advancement device on plasticity in corticomotor control of tongue and jaw muscles. J Clin Sleep Med. 2021;17(9):1805-1813.

Local anaesthesia decreases nerve growth factor induced masseter hyperalgesia.

The aim of this investigation was to evaluate the effects of local anaesthesia on nerve growth factor (NGF) induced masseter hyperalgesia. Healthy participants randomly received an injection into the right masseter muscle of either isotonic saline (IS) given as a single injection (n = 15) or an injection of NGF (n = 30) followed by a second injection of lidocaine (NGF + lidocaine; n = 15) or IS (NGF + IS; n = 15) in the same muscle 48 h later. Mechanical sensitivity scores of the right and left masseter, referred sensations and jaw pain intensity and jaw function were assessed at baseline, 48 h after the first injection, 5 min after the second injection and 72 h after the first injection. NGF caused significant jaw pain evoked by chewing at 48 and 72 h after the first injection when compared to the IS group, but without significant differences between the NGF + lidocaine and NGF + IS groups. However, the mechanical sensitivity of the right masseter 5 min after the second injection in the NGF + lidocaine group was significantly lower than the second injection in the NGF + IS and was similar to the IS group. There were no significant differences for the referred sensations. Local anaesthetics may provide relevant information regarding the contribution of peripheral mechanisms in the maintenance of persistent musculoskeletal pain.

Oral Health Status of Hospitalised Patients with Mental Disorders: Systematic Review of the Literature. / Estado de salud oral de pacientes hospitalizados con trastornos mentales: Revisión sistemática de la literatura.

BACKGROUND: According to the literature, hospitalised patients with mental disorders have a higher risk of developing cavities and periodontal disease than the general population, associated with the motor difficulty to perform adequate oral hygiene, to the adverse effects caused by drugs for the control of psychiatric symptoms, as well as the lack of oral care and clinical care. AIM: To carry out a systematic review of the literature on the oral health status of hospitalised patients with mental disorders (MD). MATERIALS AND METHODS: A systematic search of the literature was carried out in PubMed, according to the PRISMA statement methodology, through the MeSh health descriptors "Dental Caries" and "Mental Disorders" in February 2017 RESULTS: According to the different filters that were applied, 14 articles describing the oral health status were obtained - through the DMF-T index (teeth with cavities, teeth with restorations, missing teeth and teeth with necessary extraction)- of hospitalised patients with MD. CONCLUSIONS: The recognition of the importance of oral health by health professionals, carers and family members should be promoted; the oral cavity should be explored to determine the state of health in addition to instructing patients and support personnel in oral hygiene; mental health institutions should establish an intervention programme to eliminate oral infectious sites and then implement a multidisciplinary preventive programme to maintain oral health according to the MD diagnosis.

Consensus-based clinical guidelines for ambulatory electromyography and contingent electrical stimulation in sleep bruxism.

As yet, there are still no evidence-based clinical diagnostic and management guidelines for ambulatory single-channel EMG devices, like the BUTLER® GrindCare® (GrindCare), that are used in patients with sleep bruxism. Therefore, a consensus meeting was organised with GrindCare developers, researchers, and academic and non-academic clinicians experienced with the use of ambulatory EMG devices. The aim of the meeting was to discuss and develop recommendations for clinical guidelines for GrindCare usage, based on the existing clinical and research experience of the consensus meeting's participants. As an important outcome of the consensus meeting, clinical guidelines were proposed in which an initial 2-week baseline phase with the device in its inactive (non-stimulus) mode for habituation and assessment of the number of jaw-muscle activities is followed by a 4-week active phase with contingent electrical stimuli suppressing the jaw-muscle activities. As to avoid the commonly reported reduction in sensitivity to the stimuli, a 2-week inactive phase is subsequently installed, followed by a repetition of active and inactive phases until a lasting reduction in the number of jaw-muscle activities and/or associated complaints has been achieved. This proposal has the characteristics of a single-patient clinical trial. From a research point of view, adoption of this approach by large numbers of GrindCare users creates a great opportunity to recruit relatively large numbers of study participants that follow the same protocol.

Masseter corticomotor excitability is decreased after intramuscular administration of nerve growth factor.

BACKGROUND: Quantification of motor-evoked potentials (MEPs) can contribute to better elucidate the central modulation of motor pathways in response to nociceptive inputs. The primary aim of this study was to assess the modulatory effects of nerve growth factor (NGF) injection on masseter corticomotor excitability. METHODS: The healthy participants of this randomized, double blind placebo-controlled experiment were assigned to have injected into the right masseter muscle either NGF (n = 25) or isotonic saline (IS, n = 17). The following variables were assessed at baseline and 48 hr after the injection: right masseter MEP amplitude and corticomotor mapping and clinical assessment of jaw pain intensity and function. Repeated Measures ANOVA was applied to the data. RESULTS: NGF caused jaw pain and increased jaw functional disability after the injection (p < 0.050). Also, the participants in the NGF group decreased the MEP amplitude (p < 0.001) but the IS group did not present any significant modulation after the injection (p > 0.050). Likewise, the participants in the NGF group reduced corticomotor map area and volume (p < 0.001), but the IS group did not show any significant corticomotor mapping changes after the injection (p > 0.050). Finally, there was a significant correlation between the magnitude of decreased corticomotor excitability and jaw pain intensity on chewing 48 hr after the NGF injection (r = -0.51, p = 0.009). CONCLUSION: NGF-induced masseter muscle soreness can significantly reduce jaw muscle corticomotor excitability, which in turn is associated with lower jaw pain intensity and substantiates the occurrence of central changes that most likely aim to protect the musculoskeletal orofacial structures. SIGNIFICANCE: Intramuscular administration of nerve growth factor into masseter muscle causes inhibitory corticomotor plasticity, which likely occurs to prevent further damage and seems associated with lower pain intensity on function.

Revisited relationships between probable sleep bruxism and clinical muscle symptoms.

OBJECTIVES: Sleep bruxism (SB), characterized by repetitive jaw-muscle activity during sleep, is often suggested as a cause of temporomandibular disorders (TMD), orofacial pain, and headache. This study aimed to challenge the relationship between jaw-muscle electromyographic (EMG) activity during sleep and jaw muscle symptoms including pain by modulation of the levels of EMG activity. Contingent electrical stimulation (CES) using a portable single-channel EMG device was applied at different stimulus intensities to inhibit jaw muscle activity. MATERIALS AND METHODS: Sixty probable sleep-bruxers, screened and confirmed by a 2-week use of a portable EMG device, were randomly allocated into one of 3 groups (High/Low/Placebo CES). At baseline and after 2 weeks CES intervention, the participants were asked to score pain intensity, as well as unpleasantness, fatigue, tension, soreness and stiffness in their jaw muscles, on 0-10 numerical rating scales (NRS). RESULTS: Only in the High CES group, the number of EMG events/hour was significantly decreased (P = 0.024). Although the NRS scores of pain did not change, interestingly the NRS scores of unpleasantness (P = 0.037), tension (P < 0.001) and soreness (P = 0.004) in the High CES group and tiredness (P = 0.002) and soreness (P = 0.006) in the Low CES group were significantly decreased after the CES intervention compared to baseline. CONCLUSION: High intensity CES demonstrated inhibitory effect on masticatory muscle EMG activity during sleep and was associated with significant decreases in jaw muscle symptoms (unpleasantness/tiredness/soreness) but not pain responses. These findings challenge the traditional concept that probable sleep bruxism is directly related to pain but appears related to more unspecific muscle symptoms.

Importance of Standardized Palpation of the Human Temporomandibular Joint.

AIMS: To test whether standardized palpation around the lateral pole of the condyle can influence mechanical sensitivity and unpleasantness and evoke referred sensations/pain in healthy individuals. METHODS: Palpometers (0.5, 1.0, and 2.0 kg) with spherical extensions were applied around the lateral pole of the condyle in relaxed and protruded positions of the mandible for 2, 5, and 10 seconds in 30 healthy participants. Mechanical sensitivity, unpleasantness, and referred sensations/pain were assessed using a 0 to 100 numeric rating scale (NRS) for each palpation. The NRS scores were compared using analysis of variance and McNemar test. RESULTS: Participants reported significantly higher mechanical sensitivity and unpleasantness scores for the 2.0-kg stimulus compared to the 0.5- and 1.0-kg stimuli for 2, 5, and 10 seconds (mean NRS > 50; P < .001). Application of a 1.0-kg stimulus was significantly different from the 0.5- and 2.0-kg stimuli applied for 5 seconds (mean NRS < 50; P < .001). One-third of participants reported referred sensations/pain. CONCLUSION: Application of a 2.0-kg stimulus around the lateral pole of the condyle is painful and unpleasant regardless of time of palpation. Application of a 1.0-kg stimulus for 5 seconds was found to be nonpainful and not unpleasant in healthy participants. Thus, this study supports the Diagnostic Criteria for TMD recommendation for standardized examination of the TMJ and indicates that referred sensation/pain is a common finding in healthy individuals.

Sleep Bruxism and Pain.

Bruxism is an oral behavior that may lead to repetitive jaw-muscle activity characterized by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible with 2 distinct circadian manifestations: sleep bruxism or awake bruxism. They share common risk factors and lead to similar consequences for the masticatory system but may have different etiology and pathophysiology. This oral behavior has been associated with tooth wear, masticatory muscle tenderness, headaches, and painful temporomandibular disorders. Available scientific evidence does not support the view that bruxism is a direct cause of pain, which should be taken into account when treating/managing patients.

Efficacy of gamification-based smartphone application for weight loss in overweight and obese adolescents: study protocol for a phase II randomized controlled trial.

BACKGROUND: Overweight and obesity are significant public health concerns that are prevalent in younger age cohorts. Preventive or therapeutic interventions are difficult to implement and maintain over time. On the other hand, the majority of adolescents in the United States have a smartphone, representing a huge potential for innovative digitized interventions, such as weight loss programs delivered via smartphone applications. Although the number of available smartphone applications is increasing, evidence for their effectiveness in weight loss is insufficient. Therefore, the proposed study aims to assess the efficacy of a gamification-based smartphone application for weight loss in overweight and obese adolescents. The trial is designed to be a phase II, single-centre, two-arm, triple-blinded, randomized controlled trial (RCT) with a duration of 6 months. METHOD: The intervention consists of a smartphone application that provides both tracking and gamification elements, while the control arm consists of an identically designed application solely with tracking features of health information. The proposed trial will be conducted in an urban primary care clinic of an academic centre in the United States of America, with expertise in the management of overweight and obese adolescents. Eligible adolescents will be followed for 6 months. Changes in body mass index z score from baseline to 6 months will be the primary outcome. Secondary objectives will explore the effects of the gamification-based application on adherence, as well as anthropometric, metabolic and behavioural changes. A required sample size of 108 participants (54 participants per group) was calculated. DISCUSSION: The benefits of the proposed study include mid-term effects in weight reduction for overweight and obese adolescents. The current proposal will contribute to fill a gap in the literature on the mid-term effects of gamification-based interventions to control weight in adolescents. This trial is a well-designed RCT that is in line with the Consolidated Standards of Reporting Trials statement.

Spontaneous jaw muscle activity in patients with acquired brain injuries-Preliminary findings.

PATIENTS: High or excessive parafunctional jaw muscle activity is a frequent complication of acquired brain injury (ABI) and may have some similarities to bruxism. Bruxism has been associated with increased tooth wear, masseter hypertrophy and headaches. The aim of this observational study was to identify the levels of jaw muscle activity from fourteen ABI patients having different functional and cognitive levels in their early phase of neurological rehabilitation (according to their Ranchos Los Amigos Scale (RLAS) score). Nine patients were severely cognitive impairement (RLAS score 1-3): with no or little response to any external stimuli due to low arousal and five patients were with RLAS score 4-8: depending on responses to stimuli and confusion level i.e. defining that patients had enough arousal to respond and react and therefore were able to follow the instructions. A single-channel electromyographic (EMG) device was used to assess the jaw muscle EMG activity in ABI patients for two hours continuously at two different days. DISCUSSION: The mean (±SD) jaw muscle activity observed in patients with ABI was 46.9±6.5 EMG events/h with a wide range between 1-163 EMG events/h but with no significant difference between days (P=0.230). CONCLUSION: Irrespective of functional and cognitive ability scores patients with ABI had a wide range of EMG activity. The use of ambulatory single-channel EMG devices might open a path for further studies to determine levels of jaw muscle activity associated with potential side effects in ABI patients.

Agreement between jaw-muscle activity measurement with portable single-channel electromyography and polysomnography in children.

BACKGROUND: Polysomnography (PSG) is the gold standard for sleep bruxism (SB) assessment. High economical costs, complex technical equipment, and unfamiliar laboratory setting limit its use in children. AIM: To determine the night-to-night variability of electromyography (EMG) episodes during a five-night recording with the GrindCare Measure (GCM), and the agreement in the assessment of masticatory muscle activity (MMA) between GCM and PSG in children. DESIGN: Forty-seven children from clinics of Universidad CES participated. Each participant was assessed with GCM for five consecutive nights. The last night, children underwent a single-night PSG study, together with the GCM. Spearman correlation coefficients were used to analyze data. RESULTS: The frequency of SB occurrence was 'sometimes' in 12 (25.5%) and 'usually' in 19 (40.4%) children. Simultaneous measurements with GCM and PSG obtained during the fifth night of measurement were not significantly correlated. Correlation between GCM total EMG episodes and EMG episodes/h and PSG total SB episodes, SB episodes/h, total bursts and burst/h measured with PSG was also not significant. CONCLUSION: EMG measurement with GCM was not accurate to detect PSG/SB in children. There was not advantage of multiple assessment for five nights with GCM, reducing the impact of night-to-night EMG episodes' variability on the GCM/PSG correlation.

Influence of glutamate-evoked pain and sustained elevated muscle activity on blood oxygenation in the human masseter muscle.

This study aimed to investigate the effect of glutamate-evoked masseter muscle pain on intramuscular oxygenation during rest and sustained elevated muscle activity (SEMA). Seventeen healthy individuals participated in two sessions in which they were injected with glutamate and saline in random order. Each session was divided into three, 10-min periods. During the first (period 1) and the last (period 3) 10-min periods, participants performed five intercalated 1-min bouts of masseter SEMA with 1-min periods of 'rest'. At onset of the second 10-min period, glutamate (0.5 ml, 1 M; Ajinomoto, Tokyo, Japan) or isotonic saline (0.5 ml; 0.9%) was injected into the masseter muscle and the participants kept the muscle relaxed in a resting position for 10 min (period 2). The hemodynamic characteristics of the masseter muscle were recorded simultaneously during the experiment by a laser blood-oxygenation monitor. The results demonstrated that glutamate injections caused significant levels of self-reported pain in the masseter muscle; however, this nociceptive input did not have robust effects on intramuscular oxygenation during rest or SEMA tasks. Interestingly, these findings suggest an uncoupling between acute nociceptive activity and hemodynamic parameters in both resting and low-level active jaw muscles. Further studies are needed to explore the pathophysiological significance of blood-flow changes for persistent jaw-muscle pain conditions.

Systematic Mapping of Pressure Pain Thresholds of the Masseter and Temporalis Muscles and Assessment of Their Diversity Through the Novel Application of Entropy.

AIMS: To assess the diversity of pressure pain thresholds (PPTs) within the masseter and temporalis muscles by using the novel concept of entropy and to assess the differences in PPT scores between different sites of the masseter and temporalis muscles. METHODS: In this randomized, single-blinded study, the left and right masseter and temporalis muscles of 14 healthy volunteers were divided into 15 sites each, and the PPT was assessed for each of these sites. PPT assessments were performed in two different sessions. Entropy and center of gravity (COG) values were calculated for the PPTs of each muscle. Repeated measures analysis of variance was used to assess differences between muscles, sides, and sites for PPT, entropy, and COG scores. RESULTS: The main findings were: (1) PPT scores varied significantly between the masseter and temporalis muscles and within each of these muscles; (2) entropy values of PPT scores were not different between the masseter and temporalis muscles; and (3) COG values of PPT scores varied statistically, but these changes do not seem to be clinically relevant. CONCLUSION: The results of this study suggest that the anatomical layout of the masseter and temporalis muscles has implications for mechanical pain sensitivity and that areas have different sensitivities within these muscles. Furthermore, reference values for the entropy of PPTs in healthy individuals have been estimated, and comparing these values with those of patients with muscle-related pain conditions can provide quantitative information about the spatial heterogeneity of mechanical pain sensitivity, which may be a valuable clinical outcome measure.