Bite Force, Thickness, and Thermographic Patterns of Masticatory Muscles Post-Hemorrhagic Stroke.

OBJECTIVE: Stroke is a neurological deficit of cerebrovascular origin, considered a 21st-century epidemic that causes functional changes in the human body. This study aimed to evaluate the stomatognathic system of patients after hemorrhagic stroke through the bite force, thickness, and skin temperature in the region of the masseter and temporalis muscles. MATERIAL AND METHODS: Twenty-four subjects were divided into groups: post-hemorrhagic stroke; with right side of the affected body (n = 12) and without the neurological disorder (n = 12). Maximum molar bite force was verified using a digital dynamometer. Muscle thickness was measured using ultrasound images obtained at rest and during maximal voluntary contraction of the masseter and temporalis muscles. Thermographic camera was used to record the thermographic patterns of the masseter and temporalis muscles. Data were subjected to Student's t-test (P < .05). RESULTS: The maximum molar bite force showed significant differences in the right (P = .04) and left (P = .03) sides, with a reduction in force in the post-hemorrhagic stroke group on the affected and unaffected sides. There was a significant difference (P < .05) in the thickness of the left temporal muscle at mandibular rest (P = .01) between groups. The post-hemorrhagic stroke group clinically presented greater muscle thickness in almost 100% of the muscles evaluated in both clinical conditions. There were no significant differences in skin temperature in the masseter and temporal muscles between the groups. CONCLUSIONS: Our results suggest functional changes in the stomatognathic system of subjects after a hemorrhagic stroke, especially concerning molar bite force and masticatory muscle thickness in the temporal muscle (unaffected side).

High protein intake after subarachnoid hemorrhage improves oral intake and temporal muscle volume.

BACKGROUND & AIMS: Dysphagia is a common sequela following stroke. Patients with subarachnoid hemorrhage (SAH) often develop atrophy of the temporal muscle, but its clinical significance remains unclear. This study aimed to investigate whether temporal muscle volume (TMV) is related to subsequent oral intake in patients with SAH and evaluate the predictors of temporal muscle atrophy. METHODS: We performed a retrospective analysis of 60 SAH patients receiving enteral nutrition in the acute hospitalization phase at a single center between 2009 and 2019. The TMV was segmented automatically from computed tomography images and measured on admission and at week 2. Patients with a ≥20% TMV reduction were assigned to the atrophy group (n = 24) and those with a <20% TMV reduction were included in the maintenance group (n = 36). The patients' oral intake status was assessed at week 2 using the Food Intake LEVEL Scale (grade of 7-9 considered good ingestion), and the modified Rankin scale (mRS) was used at discharge (grade of 0-2 considered good prognosis). Additional data on age, sex, body mass index, severity of SAH, and protein intake were collected on day 4. RESULTS: The maintenance group had significantly better oral intake and mRS scores compared to the atrophy group. TMV maintenance significantly affected oral intake at week 2 and the mRS score at discharge. Multivariable logistic regression analysis revealed that protein intake on day 4 significantly influenced the maintenance of TMV. CONCLUSIONS: High protein nutrition in the acute stage of SAH contributes to temporal muscle maintenance and improves oral intake.

Efecto de las técnicas neuromusculares y de jones en pacientes bruxistas con cefaleas tensionales episódicas y crónicas / No disponible

INTRODUCCIÓN: El bruxismo es una disfunción temporomandibular que tensa los músculos de la masticación, especialmente los músculos temporales y maseteros, y que a su vez puede causar cefaleas tensionales episódicas o crónicas. OBJETIVOS: Valorar el efecto de las técnicas neuromusculares y de Jones aplicadas sobre el músculo temporal en la amplitud de la apertura vertical de la boca, el umbral del dolor a la presión y la extensión craneocervical, en pacientes bruxistas con cefaleas tensionales episódicas y crónicas. MATERIAL Y MÉTODOS: Estudio experimental, tipo ensayo clínico aleatorizado y doble ciego. Se realizaron con cada paciente tres sesiones de osteopatía. La muestra estuvo formada por 52 pacientes diagnosticados de bruxismo y cefaleas tensionales episódicas y crónicas, a los que se aplicó las técnicas neuromuscular y técnica de Jones en el músculo temporal (grupo experimental), o una intervención control (contacto occipital). Se llevaron a cabo mediciones antes de hacer la intervención, inmediatamente después de realizar las técnicas y tres días después de realizar las técnicas con algometría de los puntos gatillos de la musculatura temporal, inclinometría para el movimiento craneocervical, así como mediciones de la apertura vertical de la boca con pie del rey. RESULTADOS: El grupo experimental obtuvo mejoras significativas en la apertura vertical de la boca (p < 0,001), en el umbral del dolor a la presión sobre el punto seleccionado del músculo temporal (p < 0,001) y en la en extensión craneocervical (p < 0,001). CONCLUSIONES: Las técnicas neuromusculares y de Jones aplicadas sobre el músculo temporal en pacientes bruxistas con cefaleas tensionales son útiles de cara a obtener mejoras en aspectos de interés en patologías álgicas diversas a nivel craneocervical

No disponible

Effects of 4-Week Diacutaneous Fibrolysis on Myalgia, Mouth Opening, and Level of Functional Severity in Women With Temporomandibular Disorders: A Randomized Controlled Trial.

OBJECTIVE: The purpose of this study was to assess the effects of 4-week protocol of diacutaneous fibrolysis (DF) compared with simulated DF (sham-DF) on myalgia and mouth opening. METHODS: In a sham randomized controlled trial, 34 women with temporomandibular disorders and myofascial pain were randomly divided as intervention group (IG) and sham-DF group (SG). The IG received 4 weeks of real DF, and the SG received sham. Pain was assessed through the visual analog scale and pressure pain thresholds (PPTs) on the temporomandibular joint (TMJ), and over the temporal and masseter muscles. The Mandibular Function Impairment Questionnaire was used to classify the participants regarding to the severity of the functional limitation related to TMD. RESULTS: Pain scores decreased for both groups, but the IG showed lower values at week 4, with between-group differences. Bilateral temporal PPT showed higher values at week 4, with between-group differences. The SG had lower PPTs but the IG had higher PPTs, both compared to baseline results. The time-by-group interaction and the frequency of participants above 40 mm of mouth opening showed a significant difference for the IG over time with higher results at the 4-week assessment compared to its own baseline. Both groups showed lower MFIQ scores from baseline to 4-week assessment. There was a lower frequency of a moderate level of severity for the IG. No differences were observed for TMJ or for the masseter muscles PPT. CONCLUSION: Improvements were observed for visual analog scale scores and PPTs on temporal muscles. There was a group-by-time interaction in the IG, suggesting a possible potential use of DF for mouth opening.

Assessment of Masticatory Muscle Function in Patients with Bilateral Complete Cleft Lip and Palate and Posterior Crossbite by means of Electromyography.

Aim: The aim of this study was to evaluate the electrical activity of the masticatory muscles in children with a bilateral complete cleft lip and palate (BCCLP) and posterior crossbite as well as in noncleft subjects with no malocclusion. Another purpose of the study was to examine the possible factors associated with this muscle activity. Methods: The study included 52 children with mixed dentition and Class I occlusions (20 patients with nonsyndromic BCCLP and 32 subjects with no clefts). All the cleft patients had posterior crossbite. The surface electromyography (sEMG) was used to identify the electrical potentials of the temporalis and masseter muscles. The electromyographical (EMG) recordings were taken with a DAB-Bluetooth Instrument (zebris Medical GmbH, Germany) at rest and during maximum voluntary clenching (MVC). The relationships between muscle EMG activity and independent variables were identified through multivariate logistic regression analysis. Results: The EMG activity of the temporalis muscles at rest was significantly higher in BCCLP patients with malocclusion in comparison with the noncleft subjects with normal occlusion. During MVC, significantly lower electrical potentials of the temporalis and masseter muscles were observed in cleft patients compared to the noncleft group. The presence of BCCLP, unilateral posterior crossbites, increased vertical overlap, and increased overjet are factors strongly associated with higher temporalis muscle EMG activity at rest. Conclusion: The use of surface electromyography in imaging muscle function showed that children with BCCLP and posterior crossbite exhibited altered masticatory muscle potentials at rest and during clenching. The presence of unilateral posterior crossbites, increased vertical overlap, and increased overjet had a significant impact on temporalis muscle activity in cleft patients. This knowledge is important in the aspect of early and proper diagnosis and orthodontic treatment of malocclusions, thereby achieving correct occlusion and improvement in muscle function.

Muscular pattern in patients with temporomandibular joint disc displacement with reduction: an electromyographical assessment.

OBJECTIVE: Surface Electromyography of masticatory muscles (sEMG) is used as a tool to support diagnosis and treatment of Temporomandibular disorders (TMDs). The study aimed at examining jaw muscles pattern in individuals with temporomandibular joint disc displacement with reduction (TMJ/DDR). This sort of subjects was supposed to have a different muscular pattern compared to the control group. MATERIALS AND METHODS: Sixty-four women with unilateral TMJ/DDR and forty TMD-free women underwent a sEMG assessment of masticatory muscles. Descriptive statistics were performed. Student T-Test assessed differences between the two groups. Statistical significance was set at ρ < 0.05. RESULT: The t-test showed statistically significant results only in BAR and SMI scores (ρ value < 0,0001). The other measurements did not differ between the two groups. BAR index values of all healthy subjects were within the reference range. Almost the entire TMJ/DDR group had BAR index out of reference range and anteriorly placed. CONCLUSION: Women with TMJ/DDR showed an altered recruitment of the jaw muscles, with significant difference between the activity of the couple of temporalis and the one of masseters, compared to the control group. A lower chewing efficiency was found in the DDR group compared to the control one.

Intra-Day and Inter-Day Reliability of Measurements of the electromyographic signal on masseter and temporal muscles in patients with Down syndrome.

The aim of the present study was to evaluate intra-day (test) and inter-day (re-test) reliability of surface electromyography (sEMG) signals of the masseter and temporal muscles in patients with Down syndrome (DS). We determined the reliability of sEMG variables in 33 patients with DS. EMG signals were recorded at rest as well as during maximum voluntary clenching and maximum habitual intercuspation (MHI). The signals were analyzed considering the amplitude in the root mean square (RMS), mean frequency (MNF), median frequency (MDF) and approximate entropy (ApEn). The intraclass correlation (ICC2,1) for the three trials recorded during MHI in the two sessions (test and retest) revealed excellent intra-session and inter-session reliability (ICC2,1 = 0.76 to 0.97) for all sEMG variables and muscles. In the rest position, excellent reliability was found for RMS and ApEn (ICC2,1 = 0.75 to 1.00) and good to excellent reliability was found for MDF and MNF (ICC2,1 = 0.64 to 0.93). The intra-session (test) and inter-session (re-test) analyses demonstrated the reliability of nonlinear sEMG variables of the masticatory muscles in adults with Down Syndrome.

Analysis of Masticatory Muscle Activity Based on Presence of Temporomandibular Joint Disorders.

BACKGROUND This study was conducted to analyze the activity of masticatory muscles depending on the presence of temporomandibular joint disorders (TMD) when foods of various hardness are masticated. MATERIAL AND METHODS We enrolled 20 subjects (13 men and 7 women) who met our selection criteria, and they were divided into 3 groups (the Disorder Group, the Malalignment Group, and the Control Group) based on surveys and screening inspection. The average of reference voluntary contraction (RVC) was used to measure masticatory muscle activity. Using surface electromyography (SEMG) for each group during masticatory activity, the activities of the masseter muscle and temporalis muscle were measured based on the hardness of 3 different foods (soft, sticky, and hard). RESULTS Characteristics of these 3 groups prior to the experiment were identical, and subsequent findings were as follows: First, when masticating sticky food, the Disorder Group and Malalignment Group showed significant differences from the Control Group in activities of the masseter muscle and temporalis muscle (p<0.05). Second, when masticating hard food, the Malalignment Group and Control Group showed significant differences from the Disorder Group in the masseter muscle and temporalis muscle activities (p<0.05). Based on these findings, the study showed that malalignment affects movement of the temporomandibular joint during mastication of sticky food, and the temporomandibular joint movement was affected by the presence of pain during mastication of hard food. CONCLUSIONS Our results provide basic data useful in the diagnosis of temporomandibular joint disorder, as well as guiding future studies on this topic.

Spatial Distribution of Temporalis Pressure Pain Sensitivity in Men with Episodic Cluster Headache.

(1) Background: Spatial changes in pressure sensitivity have been described in migraine and tension-type headaches. Our aim was to determine differences in the spatial distribution of pressure pain sensitivity of the temporalis muscle between cluster headache (CH) patients and headache-free controls; (2) Methods: Pressure pain thresholds (PPTs) were determined over nine points covering the temporalis muscle in 40 men with episodic CH and 40 matched headache-free controls in a blinded fashion. Topographical pressure pain sensitivity maps were constructed based on interpolation of the PPTs. Patients were evaluated in a pain-free period (remission phase), at least 3 months from the last attack and without medication; (3) Results: The analysis of covariance (ANCOVA) found significant difference between points (F = 21.887; P < 0.001) and groups (F = 24.416; P = 0.602), but not between sides (F = 0.440; P = 0.508). No effect of depression (F = 0.014; P = 0.907) or anxiety (F = 0.696; F = 0.407) was observed. A post-hoc analysis revealed: 1) lower PPTs at all points in patients than in controls, 2) an anterior-to-posterior gradient in patients but not in controls, with lower PPTs located in the anterior column. Large between-groups effects were shown in all points (standardized mean difference, SMD > 0.8); (4) Conclusions: Bilateral pressure pain hypersensitivity to pressure pain in the temporalis muscle and an anterior-to-posterior gradient to pressure pain was observed in men with episodic CH.

Ankylosing spondylitis presenting with enthesitis at an uncommon site and fever of unknown origin.

A 58-year-old man presented with a 2-month history of arthralgia and bilateral temporal region pain, and a 1-month history of fever. He had had refractory neck pain since his 20s. Reduced cervical and lumbar mobility was observed. Radiographs of cervical and thoracic vertebrae disclosed syndesmophytes. Pelvic radiographs showed sclerosis in the right sacroiliac joint and ankylosis in the left sacroiliac joint. MRI with contrast enhancement showed enthesitis in the upper extremities and enhancement in the bilateral temporal muscle, which indicated enthesitis of temporal muscle. He was diagnosed with ankylosing spondylitis based on the limitation in mobility of the lumbar spine and radiographic findings. To the best of our knowledge, this is the first report describing enthesitis of the temporal muscle. This case highlights that ankylosing spondylitis can be accompanied with enthesitis at the temporal muscle and fever of unknown origin at the initial presentation.

The Electrical Activity of Masseter and Anterior Temporal Muscles in Patients With Unilateral Cleft Lip and Palate.

This study aimed to determine the electrical activity of masseter and anterior temporal muscles in patients with unilateral cleft lip and palate (CLP) and compare it with healthy volunteers. The study involved 20 female patients (mean age 20 ±â€Š4 years) with unilateral cleft lip and palate who had undergone lip and palate surgery in childhood and finished the first-phase orthodontic therapy with level and align teeth. Twenty age- and sex-matched volunteers with no cleft lip and palate were involved as controls. Electromyographic (EMG) signals of masseter and anterior temporal muscles were recorded at rest position, during swallowing and during maximum bite force (MBF). EMG signals at different test conditions were compared between the cleft and noncleft sides of CLP patients and between CLP patients and healthy individuals. The EMG potentials of masseter (rest, swallowing, MBF) and temporal (rest, MBF) muscles were significantly higher in the cleft than the noncleft side of CLP patients (P value <0.001). Generally, patients with unilateral cleft lip and palate experienced a significant increase in the electrical activity of the masseter and temporal muscles in both sides compared to the control group (P <0.05). In conclusion, patients with unilateral cleft lip and palate exhibit overall greater masticatory muscle activity compared to healthy individuals. The asymmetric masticatory function in subjects with unilateral cleft lip and palate may be associated with severe consequences such as asymmetric facial growth, implying the importance of early diagnosis and orthodontic treatment to achieve a favorable environment for balanced facial growth in CLP affected patients.

Spinocerebellar ataxia: Functional analysis of the stomatognathic system.

BACKGROUND: Neurodegenerative diseases that affect the cerebellum, especially in elderly individuals, cause impairment of motor coordination and quality of life. The presente study evaluated the electromyographic activity and thickness of the right and left masseter and temporal muscles, and the maximum molar bite force of individuals with spinocerebellar ataxia. MATERIAL AND METHODS: Twenty-eight individuals were divided into two groups: those with (n=14) and without (n=14) spinocerebellar ataxia. Data on the masticatory muscles obtained from the electromyographic activity (resting, right and left laterality and protrusion), muscle thickness (maximal voluntary contraction and tensile strength) and maximum bite force (right and left) were tabulated and descriptive analysis using Student's t-test (P ≤ 0.05). RESULTS: In the comparison between groups, greater electromyographic activity was demonstrated for individuals with spinocerebellar ataxia, with a statistically significant difference in protrusion and laterality for the temporal muscles (P = 0.05). There was no statistically significant difference between the groups for masticatory muscles thickness in the conditions evaluated. For maximum molar bite force, the group with spinocerebellar ataxia showed lower bite force (P ≤ 0.05). CONCLUSIONS: The data obtained suggest that spinocerebellar ataxia promotes functional reduction in the stomatognathic system, mainly affecting the electromyographic activity and bite force, hindering chewing, with a resultant alteration of nutritional intake and a decrease of quality of life.

Spinocerebellar ataxia: Functional analysis of the stomatognathic system

Background: Neurodegenerative diseases that affect the cerebellum, especially in elderly individuals, cause impairment of motor coordination and quality of life. The presente study evaluated the electromyographic activity and thickness of the right and left masseter and temporal muscles, and the maximum molar bite force of individuals with spinocerebellar ataxia. Material and Methods: Twenty-eight individuals were divided into two groups: those with (n=14) and without (n=14) spinocerebellar ataxia. Data on the masticatory muscles obtained from the electromyographic activity (resting, right and left laterality and protrusion), muscle thickness (maximal voluntary contraction and tensile strength) and maximum bite force (right and left) were tabulated and descriptive analysis using Student’s t-test (P ≤ 0.05). Results: In the comparison between groups, greater electromyographic activity was demonstrated for individuals with spinocerebellar ataxia, with a statistically significant difference in protrusion and laterality for the temporal muscles (P = 0.05). T here was no statistically significant d ifference b etween t he g roups for m asticatory muscles thickness in the conditions evaluated. For maximum molar bite force, the group with spinocerebellar ataxia showed lower bite force (P ≤ 0.05). Conclusions: The data obtained suggest that spinocerebellar ataxia promotes functional reduction in the stomatognathic system, mainly affecting the electromyographic activity and bite force, hindering chewing, with a resultant alteration of nutritional intake and a decrease of quality of life

No disponible

Distribución nerviosa interna del músculo temporal humano: consideraciones anatómicas y quirúrgicas / Internal nervous distribution of the human temporal muscle: anatomical and surgical considerations

Resumen Introducción: Conocer en detalle la inervación interna del músculo temporal humano permite realizar múltiples técnicas quirúrgicas y tratamientos de patologías que involucran al territorio craneofacial. Si bien en la literatura se ha descrito la inervación interna del músculo temporal humano basado en micro-disección directa, la técnica de tinción de Sihler es una herramienta ventajosa para el estudio anatómico ya que permite observar ramos nerviosos pequeños sin perder su relación tridimensional con las fibras musculares. Objetivo: Describir la distribución nerviosa al interior del músculo temporal humano en cadáveres al aplicar el método de Sihler y analizar su asociación anátomo quirúrgica. Materiales y Método: Ocho músculos temporales humanos previamente disecados fueron sometidos al método de tinción de Sihler. Cada una de las muestras se observó bajo lupa estereoscópica y transiluminación; finalmente para su descripción se dividió al músculo en tres regiones. Resultados: Se determinó la presencia de tres troncos nerviosos principales: el temporal profundo anterior, el temporal profundo medio y temporal profundo posterior, los que discurren de profundo a superficial. Además, se observaron ramos colaterales de menor calibre del nervio temporal profundo posterior que en forma de arco comunican las tres regiones del músculo. Conclusión: Se describió una distribución nerviosa interna común para los músculos estudiados en las tres dimensiones del espacio, conocimiento útil para innovar en terapias clínico-quirúrgicas del territorio craneofacial.

Introduction: Knowing in detail the inner innervation of the human temporal muscle allows to perform multiple surgical techniques and treatments of pathologies that involve the craniofacial territory. Although the internal innervation of the human temporal muscle based on direct microdissection has been described in the literature, the Sihler staining technique is an advantageous tool for anatomical study since it allows observing small nerve branches without losing its three-dimensional relationship with muscle fibers. Aim: To describe the nervous distribution within the human temporal muscle in cadavers by applying the Sihler method and analyzing its surgical anatomical association. Materials and Method: Eight previously dissected human temporal muscles were subjected to the Sihler staining method. Each one of the samples was observed under stereoscopic magnification and transillumination, finally for its description the muscle was divided into three regions. Results: The presence of three main nervous trunks was determined: the anterior deep temporal, the deep medium temporal and the posterior deep temporal, those that run from deep to superficial. In addition, collateral branches of lesser caliber of the posterior deep temporal nerve that in the form of an arc communicate the three regions of the muscle were observed. Conclusion: A common internal nervous distribution was described for the muscles studied in the three dimensions of space, useful knowledge to innovate in clinical-surgical therapies of the craniofacial territory.

Trigeminocardiac Reflex: Case Report and Literature Review of Intraoperative Asystole in Response to Manipulation of the Temporalis Muscle.

BACKGROUND: The trigeminocardiac reflex is a sudden onset of bradycardia, hypotension, apnea, or gastric hypermotility in response to stimulation of the trigeminal nerve. CASE DESCRIPTION: A 60-year-old female underwent a left orbitozygomatic craniotomy to debulk a large skull base epidermoid cyst compressing the brainstem and cranial nerves. Intraoperatively, retraction of the temporalis muscle consistently produced asystole. Cessation of retraction resulted in prompt return of sinus rhythm. CONCLUSIONS: Our report describes an unusual and extreme example of the trigeminocardiac reflex and explores possible etiologies. This is the third reported surgical case in which manipulation of the temporalis muscle alone was sufficient to elicit bradycardia and asystole, and the first such case within the context of neurosurgery. We emphasize the importance of surgical teams to be cognizant of such extreme examples of this reflex.

Evaluation of the electromyographic fatigue of the masseter and temporalis muscles in individuals with osteoporosis.

OBJECTIVES: The objective of this study was to evaluate the electromyographic fatigue of the masseter and temporalis muscles in individuals with and without osteoporosis. METHODS: Median frequency of the initial, mid, and final periods of the electromyographic signal in the 33 subjects with osteoporosis (OG) and 33 subjects without osteoporosis [control (CG)] was analyzed. RESULTS: OG showed a decrease in median frequency along the electromyographic signal, with a significant difference for the right masseter: initial vs. mid periods, initial vs. final periods; left masseter: initial vs. final periods; temporal (right and left): initial vs. mid periods, initial vs. final periods, and mid vs. final periods. Percentage comparison of median frequency between the initial and mid periods and between initial and final periods in the OG showed a significant difference in the masticatory muscles. DISCUSSION: The findings suggest that osteoporosis is associated with changes in the function of masticatory muscles, especially when measured by electromyographic fatigue.

Evaluation of masticatory muscle activity in patients with unilateral posterior crossbite before and after rapid maxillary expansion.

Objectives: The relationship between unilateral posterior crossbite (UPCB) and the possible asymmetric activation of the jaw muscles in children is still under debate. This study aimed at evaluating the jaw muscle activity of children with UPCB before and after rapid maxillary expansion (RME) by means of surface electromyography and a standardized sampling protocol. Subjects and methods: Twenty-nine children with UPCB (UPCB-group, mean age 9.6 ± 1.6 years) and 40 UPCB-free controls (Control-group, 10.5 ± 1.1) were recruited. The activity of the left and right anterior temporalis (AT) and superficial masseter muscles (MM) was recorded during maximum voluntary clenching and a chewing task (T0). In the UPCB-group, data were collected, also, after the correction of the UPCB with RME (T1) and 6 months later (T2), without any further treatment. Electromyographic indices comparing the activity of paired muscle were computed via software to estimate the extent of asymmetric AT and MM activity. Paired and unpaired t-test or Wilcoxon-signed rank and Mann-Whitney U test, ANOVA or Friedman test and chi-squared test were used in the statistical analysis. Results: Both groups presented with asymmetric activity of the muscles, which did not differ between groups (T0, all P > 0.05). The treatment determined a decrease in muscular activity (T1, P = 0.040), and a more asymmetric pattern of muscle activation during chewing (T1, P = 0.040), which returned similar to baseline values at T2 (all P > 0.05). Conclusions: UPCB does not contribute to an asymmetric activation of AT and MM during functional tasks. The treatment of UPCB by RME did not determine a more symmetric activity of the assessed muscles.

Chronic stress and temporalis muscle activity in TMD patients and controls during sleep: a pilot study in females.

OBJECTIVES: The aim of this study was to assess the correlation between chronic stress and temporalis muscle activity during four nights. MATERIAL AND METHODS: Forty-four female subjects were recruited in five dental practices located in different areas of the federal state of Saarland, Germany (dental practice network in Saarland). The following inclusion criteria were used: female, aged between 18 and 65, no somatization or depression, and no pain medication, graded chronic pain status < 3. Both subjects reporting about sleep bruxism and subjects negating sleep bruxism during anamnesis were included. Anamnestic issues, sleep bruxism, anxiety, and chronic stress were assessed using validated questionnaires. Temporalis muscle activity was measured for four nights using a portable electromyographic device. Correlation coefficient was used to assess the correlation (Spearman-correlation) between chronic stress and number of temporalis muscle episodes/hour and between anxiety and the number of episodes/hour. RESULTS: The analysis showed that the factors "work overload" (adulthood chronic stress because of too many demands at work) and "pressure to perform" (necessity to be successful at work) were significantly correlated with the number of temporalis muscle episodes per hour. In contrast, anxiety was not correlated with temporalis muscle episodes per hour. CONCLUSIONS: Work-related chronic stress seems to be associated with an increased level of temporalis muscle activity during sleep. CLINICAL RELEVANCE: During anamnesis, work-related aspects should be assessed in females presenting with sleep-bruxism.

Effect of Breast Cancer Treatment on the Stomatognathic System.

Breast cancer is the most common cancer affecting women in the world and provides functional changes in the human body. Evaluate women submitted to unilateral mastectomy, through electromyographic activity (mandibular rest, right and left laterality, protrusion, maximum voluntary contraction with and without Parafilm, habitual and non-habitual mastication) and thickness (rest and maximum voluntary contraction) of the right temporal muscle (RT), left temporal (LT), right masseter (RM) and left masseter (LM), also the molar bite force (right and left) and compare the data with healthy women. Material and Methods: 32 women were divided into two groups: unilateral mastectomy group (MG), average ± standard deviation 56.50±14.50 years (n=16) and without the disease group (CG), average ± standard deviation 56.56±14.15 years (n=16). The normalized electromyographic data, muscle thickness and maximal molar bite force were tabulated and submitted to statistical analysis (SPSS 21.0; student t test, p≤0.05). Significant statistical differences between MG and CG were found in right laterality, for RM (p=0.02); left laterality, for LT (p=0.01); chewing with peanuts, for RM (p=0.04); chewing with raisins, for LM (p=0.04) and right molar bite force (p=0.03). There was no statistically significant difference between MG and CG for muscle thickness. The results of this study suggest that women undergoing unilateral mastectomy may present functional changes, with emphasis on muscular hyperactivity, lower masticatory efficiency and lower maxillary bite force.