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Indirect bypass using autologous tissue is effective in Moyamoya disease, especially among pediatric patients. This study aimed to evaluate the effectiveness of indirect bypass using DuraGen (absorbable artificial dura mater composed of collagen matrix), as a substitute for autologous tissue in a rat model of chronic cerebral hypoperfusion. Male Wistar rats were subjected to bilateral internal carotid artery occlusion and divided into three groups: a control group without bypass surgery, a group wherein indirect bypass was performed using the temporalis muscle (encephalo-myo-synangiosis [EMS] group), and a group wherein DuraGen was used (Dura group). The ratio of the number of vascular endothelial cells, detected by antibodies to CD31 and glucose transporter type 1 (Glut-1), on the operative side to that on the non-operative side was measured and compared between the three groups. The ratio of CD31-positive cells was 1.50 ± 0.13 and 1.92 ± 0.29 in the EMS and Dura groups, respectively, and that of Glut-1-positive cells was 1.32 ± 0.10 and 1.53 ± 0.18 in the EMS and Dura groups, respectively. No significant difference was observed in the ratio of vascular endothelial cells on the bypass side between the EMS and Dura groups. Indirect bypass with DuraGen resulted in an increased ratio of vascular endothelial cells, equivalent to that of an indirect bypass with the temporalis muscle in a rat model. Thus, in an actual indirect bypass for patients with Moyamoya disease, the use of DuraGen may produce the same angiogenesis as using autologous tissue. [ABSTRACT FROM AUTHOR]

Aim: Aberrative occlusal contacts were associated with Temporomandibular disorder (TMD), but whether stabilization splints with therapeutic exercises alleviate the symptoms is unclear. Hence, this study aims to compare the short-term efficacy of occlusal splint therapy and the synergistic effect of therapeutic exercise with occlusal splint therapy for 3 weeks in individuals with TMD. Settings and Design: in-vivo observational pilot study. Materials and Methods: Fourteen participants were grouped based on the type of treatment: Group A, assigned with combination therapy, stabilization splint with therapeutic exercises, and Group B, with only stabilization splint therapy. Surface electromyography (EMG) was taken to evaluate the masseter and temporalis muscle activity at baseline and 2nd week. The patient's perception of TMD was evaluated using the Fonseca questionnaire at baseline, 48 h, 14th, and 21st days. Statistical analysis: Chi-square statistical analysis was applied to the quantitative data obtained from the Fonseca questionnaire and EMG analysis, with P < 0.05 as significant. Results: Fonseca questionnaire revealed a significant difference between the two groups at 48 h (P < 0.05). EMG outcome showed no significant difference between the groups at baseline and 14th day (P > 0.05). However, the mean muscle activity recorded at the masseter in Group B was increased on 14th day (56.5 ± 3 μV) and an isotonic muscle pattern was observed in Group A. Conclusion: Combination therapy, which included stabilization splint and home care exercises for moderate to severe TMD patients, led to earlier curative changes in the temporomandibular joint and improved functional jaw movements, along with a reduction in pain. An isotonic muscle activity pattern was also observed, confirming the effect of combination therapy. [ABSTRACT FROM AUTHOR]

Objective: This study aims to systematically review and meta-analyze the electromyographic activity of masticatory muscles in cleft palate and non-cleft patients, and identify influencing factors. Design: Systematic Review and Meta-analysis Patients and Exposures: Patients with cleft lip/ palate Comparison: Patients without CL/P. Main Outcome Measures: Electrical activity of masseter and temporalis muscles at rest and during peak activation Results: After a comprehensive search in MEDLINE, Web of Science, EMBASE, Scopus, and Cochrane's CENTRAL up to December 2022, without language or date restrictions. Eligible trials were selected based on the PECO question and assessed for bias using Cochrane's ROBINS-E tool. Eight clinical trials with 474 participants were included in the review. Then relevant data was extracted from included studies using customized forms. A random-effects meta-analysis was performed to combine the results of the studies, meta-analyses showed that CL/P patients have elevated electrical activity in the masseter (P =.01) and temporalis (P = <.01) muscles at rest compared to non-cleft control patients. During maximum bite force, cleft patients exhibited a statistically significant decrease in electrical activity in both the masseter (P =.03) and temporalis (P = <.01) muscles. Conclusions: According to our meta-analysis, cleft patients exhibited increased resting muscle activity but decreased activity during maximum bite force, indicating reduced efficiency of masticatory muscles compared to non-cleft patients. These differences can be attributed to anatomical variations, compensatory mechanisms, and previous treatments. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Objective Methods Results Conclusion Botulinum toxin Type A (BTX‐A) is increasingly used in the management of myofascial pain; however, the evidence to support this treatment modality is still inconclusive.To evaluate the change in days with functional jaw pain after one session of BTX‐A or placebo injections into the masseter and temporalis muscles in subjects with jaw myalgia. The hypothesis was that BTX‐A is effective in reducing the number of days with functional jaw pain.This was a randomised, double‐blind, parallel group study in subjects with jaw myalgia. After randomisation, BTX‐A or placebo injections were made in the masseter and temporalis muscles. The number of days with jaw pain on function was evaluated after 2 months. Adverse events were registered.Twenty‐three subjects were randomly assigned to BTX‐A and 22 to placebo. Between baseline and the 2‐month follow‐up, the number of days with jaw pain at function changed from a median (interquartile range) of 14 (4) to 10.5 (6) days in the BTX‐A group and from 14.0 (1.5) to 14 (5) in the saline group (p < 0.585). Adverse events were mild and transient and similar in the two groups.A single treatment of BTX‐A injections in the masseter and temporalis muscles was not effective in treating jaw myalgia. However, an adequately powered study might provide sufficient support for efficacy. [ABSTRACT FROM AUTHOR]

Background: Migraine diagnosis is mainly clinically based on symptomatology. The objectives of this study were (1) to determine the ability of pain thresholds to differentiate between women with and without migraines and (2) to determine the ability of clinical, psychological and psychophysical variables to differentiate between women with episodic and chronic migraines. A diagnostic accuracy study was conducted. Methods: Pressure-pain thresholds (PPTs) at one trigeminal (temporalis muscle) and one extra-trigeminal (cervical spine) and two distant-pain free (second metacarpal and tibialis anterior muscle) areas, as well as dynamic pain thresholds (DPTs), were bilaterally assessed in 100 women with migraines, recruited from tertiary hospitals (50% episodic, 50% chronic), and 50 comparable women without headaches. Migraine pain features (headache diary), migraine-associated burden (HDI), anxiety and depressive levels (HADS) and state (STAI-S)–trait (STAI-T) anxiety were also evaluated. The area under the receiver operating characteristic (ROC) curve, with optimal cut-off points, as well as the sensitivity, specificity and positive/negative likelihood ratios (LR) for each variable, were calculated. The women with migraines showed lower PPTs and DPTs than those without migraines. Results: The women with chronic migraines showed lower PPTs in the temporalis muscle than the women with episodic migraines. No clinical, psychological or psychophysical variables exhibited acceptable ROC values (≥0.7) for differentiating between women with and without migraines or between women with episodic and chronic migraines. Conclusions: Although the women with migraines had widespread pressure-pain hyperalgesia, neither the clinical, psychological nor psychophysical (pain threshold) variable exhibited the proper diagnostic accuracy to distinguish between women with and without migraines or between women with episodic and chronic migraines. New studies should clarify the clinical relevance of the findings of the current study. [ABSTRACT FROM AUTHOR]

Background and Objectives: Sport climbing's popularity has grown with its inclusion in the Olympics and increased accessibility. Understanding the relationship between hand dominance, grip strength, endurance, and the involvement of masticatory and neck muscles can provide valuable insights into the neuromuscular adaptations specific to sport climbing, potentially aiding performance optimization and injury prevention in intermediate and advanced climbers. This study analyzes if the dominant hand has greater isometric endurance and isometric manual grip strength parameters than the non-dominant one and examines its relation to the masticatory and neck muscles in intermediate and advanced sport climbers. Materials and Methods: The study was conducted on 41 participants who were divided into two groups according to the IRCRA classification. A level 2 (Lv2) group consisting of 18 climbers and a level 3 (Lv3) group consisting of 23 climbers were identified. First, isometric manual grip strength and isometric endurance were measured using a dynamometer following the protocol of the first three and the last three repetitions (PC3) and the first six and the last six repetitions (PC6). Next, masticatory and neck muscle activity was assessed using surface electromyography, following the same protocol. Results: Greater activity of the temporalis muscle was observed on the non-dominant side in the advanced climber's group (p = 0.045). The decrease in bioelectric activity was lower on the dominant side in group Lv3 compared to Lv2. In intermediate climbers, the bioelectrical activity of the masseter muscles in PC3 was greater on the non-dominant side, and in PC6, was greater on the dominant side. The digastric muscles showed a greater decrease in isometric endurance on the non-dominant side. Conclusions: Advanced climbers demonstrated greater isometric endurance and isometric manual grip strength parameters in both dominant and non-dominant hands compared to intermediate climbers. The masticatory muscles exhibited higher electromyographic activity on the non-dominant side in the masseter muscles and higher electromyographic activity on the dominant side in the temporalis muscles and digastric muscles. [ABSTRACT FROM AUTHOR]

Objectives: To compare masticatory muscles' recruitment in patients with temporomandibular disorders and asymptomatic control subjects. To evaluate if the masticatory muscles' recruitment pattern may predict symptoms' improvement after temporomandibular disorders treatment. Materials and Methods: Standardized surface electromyography of anterior temporalis and superficial masseters muscles were recorded and compared at baseline in 26 patients with arthrogenous temporomandibular disorders (study group) and 26 asymptomatic subjects (control group). The study group was treated pharmacologically and by means of five arthrocentesis sessions. Pre‐, during‐, and post‐treatment pain and mandibular function were assessed and compared among timepoints. Clinical improvement in terms of pain and mandibular function was correlated with pre‐treatment standardized surface electromyography values. Results: Temporomandibular disorders patients showed improved maximum mouth opening and pain during and after treatment with arthrocentesis compared to baseline (T‐test p < 0.01). Standardized surface electromyography values were significantly different in temporomandibular disorders subjects compared to controls (T‐test p < 0.05). Improvement in pain at rest after treatment was inversely correlated with pre‐treatment masseters standardized surface electromyography symmetry (R‐coefficient 0.3936; p < 0.05). Conclusions: Temporomandibular disorders patients showed a different muscular recruitment pattern compared to controls. The lesser the pre‐treatment masseters symmetry, the greater the improvement of pain at rest after treatment. [ABSTRACT FROM AUTHOR]

To evaluate the effects of a multimodal management technique combining surgical muscle wrapping, clipping, and flow-diverter stent (FDS) placement in patients with ruptured blood blister-like aneurysms (BBAs) in the internal carotid artery (ICA). In a retrospective case series review from 2020 to 2023, 3 patients with ruptured ICA BBAs underwent multimodal management, an approach combining muscle wrapping, surgical clipping, and FDS embolization. The aneurysm sac was initially packed and wrapped with multiple tailored temporalis muscle grafts and then secured using fenestration clips, with good preservation of the ICA branches. The FDS was placed 2–3 weeks after the clipping. All 3 patients had right ICA BBAs (mean age, 52 years). The modified Hunt and Hess grades ranged from 2 to 3, and the Fisher grades ranged from 3 to 4. The mean angiography follow-up time was 27.7 months (15, 31, and 37 months). There were no instances of symptomatic vasospasm or visible ischemic stroke during follow-up computed tomography. No patient required cerebrospinal fluid shunt implantation, and all achieved favorable neurological outcomes (modified Rankin scale 0–1). Follow-up digital subtraction angiography revealed no evidence of aneurysm recurrence or significant ICA stenosis. We discuss a promising multimodal management approach for ruptured ICA BBAs combining muscle wrapping, surgical clipping, and FDS embolization. This technique was safe and effective in preventing re-rupture, achieving positive short-term clinical outcomes. Further research and more extensive studies are required to validate the long-term efficacy of this approach. [ABSTRACT FROM AUTHOR]

Aim: To assess the changes in muscle activity after replacing the missing teeth or teeth with implants in distal extension edentulous patients and to evaluate the patient's satisfaction levels. Materials and Methods: This was a single-group experimental study, based on convenience sampling with a sample size of 40 patients. Only unilateral mandibular distal extension edentulous sites were included and endo-osseous dental implants were placed in delayed protocol. Electrical activities of the masseter and temporalis muscles were recorded at rest and clench before, immediately, and one month after the cementation using electromyography. Patient satisfaction was analyzed through a questionnaire. Descriptive statistics an inferential statistics with repeated measures of ANOVA followed by the Bonferroni post hoc test were done to analyze the study data. P value <.05 would be considered statistically significant for all the analyses. Results: Right temporalis showed significantly higher surface electromyography (sEMG) activity at one-month post cementation than baseline at rest and clench. Similarly, the left temporalis has shown significant sEMG activity at one-month post cementation than baseline at clench. However, there was no statistical difference with the right and left masseter. The implant-supported prosthesis was well received by the majority of patients. Conclusion: Definitive improvement in the electrical activity of the temporalis before and after the replacement of prosthesis was noticed with positive patient satisfaction levels with implant-supported prosthesis. [ABSTRACT FROM AUTHOR]

The analysis of the masticatory cycle plays a fundamental role in studying the functions of the stomatognathic system and evaluating temporomandibular dysfunctions (TMD). The primary objective of this study is to investigate the complex interplay between mandibular kinematics and surface electromyography (sEMG) activity during the masticatory cycle using advanced 4D dentistry technology in 22 healthy subjects (without TMD). By employing electromyography, it becomes feasible to capture the electrical activity of the masticatory muscles throughout the chewing process. The BTS TMJOINT (© 2023 BTS Bioengineering, Garbagnate Milanese, MI, Italy) electromyograph was utilized in this study. Mandibular tracking, on the other hand, allows for recording the movements of the mandible during chewing and condylar slopes. This latest technology (ModJaw®, Tech in motion™, Villeurbanne, France) utilizes motion sensors placed on the jaw to accurately track three-dimensional movements, including jaw opening, closing, and lateral movements. Nowadays, in clinical gnathology, it is common practice to examine masticatory function by analyzing mandibular kinematics and muscle contraction as distinct entities. Similarly, the results obtained from these analyses are typically assessed independently. The investigation of a correlation between electromyography data and mandibular kinematics during the masticatory cycle could provide several advantages for clinicians in diagnosis and lead to a combined analysis of muscle activities and intraarticular dynamics. In conclusion, it can be inferred from the results obtained in the present study that the chewing cycle with a greater vertical movement results in increased masseter muscular activity, and condylar slopes are positively correlated to an increase in temporalis muscle activation. This comprehensive approach can provide valuable insights into the relationship between muscle activity and mandibular movement, enabling clinicians to gain a deeper understanding of the functional dynamics of the stomatognathic system. [ABSTRACT FROM AUTHOR]

Objectives: The Functional Clear Aligner (FCA) is a novel orthodontic appliance designed for the treatment of Class II malocclusion with mandibular retrognathia in adolescents. The aim of this study was to investigate the biomechanical characteristics of the masticatory muscles, jawbone, and temporomandibular joint (TMJ) during mandibular advancement using either FCA or Class II elastics combined with clear aligner (Class II elastics) through finite element analysis. Materials and methods: A 3D finite element model of the 'muscle-jawbone-TMJ-appliance' system was constructed based on CBCT and MRI images of a boy with skeletal Class II malocclusion. Masticatory muscles included masseter, temporal, medial pterygoid, and lateral pterygoid muscles. The TMJ consists of the temporal bone's glenoid fossa, disc, and mandibular condyle. To observe the biomechanical characteristics of the muscles and TMJ during orthodontic appliance wearing and the retention phase, two different protocols were used: Model 1: The mandibular advancement using FCA; Model 2: The mandibular advancement using Class II elastics. Results: The FCA group produced greater and more coordinated masticatory muscle forces compared to the Class II elastics group. Temporal and masseter muscles exhibited the most pronounced variation in muscle strength during mandibular advancement. The FCA group exhibited greater TMJ region stress compared to the Class II elastics group. Interestingly, the stress on the articular discs in both models decreased over time. Tensile stresses were observed in both the condyle and the posterior region of the articular fossa. Conclusion: During skeletal Class II malocclusion treatment, masticatory muscle forces and stress on the TMJ were higher in the FCA group compared to the Class II elastics group. In both models, stress cushioning was provided by the articular disc. [ABSTRACT FROM AUTHOR]

Background: This study aimed to elucidate the effects of botulinum toxin A (BoNT-A) treatment for patients diagnosed with masseter hypertrophy on the temporalis muscle, with a particular focus on assessing alterations in muscle thickness, electromyographic (EMG) activity, and the development of muscle pain. Methods: The present randomized triple-blinded clinical trial enrolled 26 female participants aged between 25 and 50 years complaining about masseter hypertrophy. Participants received 75U of BoNT-A (abobotulinumtoxinA) in both masseter muscles and after three months were randomized to receive a second treatment session of saline solution (S-BoNT-A) or BoNT-A (M-BoNT-A). Longitudinal assessments included temporalis muscle thickness through ultrasound, EMG activity, subjective pain, and masseter prominence severity after one, three, and six months of the first injection session. Muscle thickness, EMG, and subjective pain were analysed using two-way ANOVA with repeated measures and post hoc Sidak test, and for masseter prominence severity, Friedman and Mann–Whitney tests were used. Results: Regarding inter-group comparisons, a higher muscle thickness (p < 0.02) and a higher EMG activity (p < 0.01) were found in the M-BoNT-A group at the 6-month follow-up. For subjective pain assessments, inter-group comparisons showed a higher prevalence of painful regions in M-BoNT-A group at the 6-month follow-up (p < 0.02). No significant differences were found in masseter prominence severity at the 6 months assessment between groups. Conclusion: BoNT-A treatment for masseter hypertrophy lead to structural and functional changes in the temporalis muscle, presenting higher changes after multiple injections of this treatment. Level of Evidence I: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266. [ABSTRACT FROM AUTHOR]

Patients with petrous bone cholesteatoma most commonly present with hearing loss and facial paralysis. Other clinical presentations can include otorrhea, tinnitus, aural fullness, otalgia, and dizziness. Here, we report a patient with petrous bone cholesteatoma who presented with cerebrospinal fluid rhinorrhea. This patient was initially misdiagnosed with rhinogenic cerebrospinal fluid leakage, and was finally diagnosed with the supralabyrinthine type of petrous bone cholesteatoma. During the surgical repair through the transmastoid trans-superior semicircular canal approach, the fistula was found in the superior wall of the internal auditory canal. He had satisfactory outcomes after the surgery, with no recurrent cerebrospinal fluid rhinorrhea. [ABSTRACT FROM AUTHOR]

We report the case of a cochlear implant patient who developed multiple infections with device extrusion necessitating explanation and reimplantation twice. An approach using a vancomycin washout followed by a temporalis muscle rotation and scalp rotation flap was utilized to salvage the device. [ABSTRACT FROM AUTHOR]

Fatigue of temporomandibular joint (TMJ) tissues reflects the effects of magnitude (energy density; ED) and frequency of loading (jaw muscle duty factor; DF). This observational study measured these variables and tested for differences in mechanobehavior scores (MBS = ED2 × DF) and component variables in subjects with and without TMJ disc displacement (±D). In accordance with Institutional Review Board and STROBE guidelines, written informed consent was obtained, and examination and imaging protocols identified eligible adult subjects. Specifically, magnetic resonance imaging was used to assign subjects' TMJs to ±D groups. Subjects were trained to record in-field jaw muscle activities, from which DFs (percentage of recording time) were determined. EDs (mJ/mm3) were estimated using modeled TMJ loads and in vivo dynamic stereometry. Multivariate analysis of variance, post hoc independent t tests, and K-means cluster analysis identified significant group differences (P < 0.05). Of 242 individuals screened, 65 females (TMJs: 78 +D, 52 −D) and 53 males (TMJs: 39 +D, 67 −D) participated. Subjects produced 312 daytime and 319 nighttime recordings of average duration 6.0 ± 0.2 h and 7.6 ± 0.1 h, respectively, and 219 (114 right, 105 left) intact dynamic stereometry recordings. Average EDs were 2-fold and significantly larger in +D than −D TMJs (P < 0.0001). DFs were on average 3-fold larger during the daytime versus nighttime for both masseter and temporalis muscles and 1.8- and 3.0-fold larger for the masseter versus temporalis muscle during the daytime and nighttime, respectively. Daytime masseter MBSs for +D TMJs in females were the largest overall at 621 ± 212 (mJ/mm3)2% and 2- to 43-fold larger versus −D TMJs in both sexes during daytime and nighttime. Cluster analysis (P < 0.0001) identified groups 2 and 3, which comprised 87% +D TMJs and had average MBSs 21-fold larger than group 1. The results show MBS as a potential biomarker to predict homeostasis versus progression or reversal of degenerative TMJ structural changes. [ABSTRACT FROM AUTHOR]

This document is a letter to the editor discussing the topic of trismus, or difficulty opening the mouth, in patients with head and neck tumors who have undergone radiotherapy. The letter highlights the use of advanced radiotherapy techniques, such as Intensity Modulated Radiotherapy Technology (IMRT) and Volumetric Modulated Arc Therapy (VMAT), in the treatment of head and neck cancers. The study conducted a prospective cohort study on 14 patients receiving IMRT/VMAT and found a correlation between radiation doses to the masticatory muscles and temporomandibular joint and the development of trismus. The study also reported declines in nutritional status and quality of life post-treatment. Further research is being conducted to investigate additional risk factors for trismus. [Extracted from the article]

Background: Temporomandibular Disorders (TMD) is the dysfunction of group of muscles and bones in the joint area, the main symptoms of TMD are the pain of the chewing muscles and (or) the temporomandibular joints, mandibular movement disorders and joint noise. This study was designed to explore the therapeutic effects following Individual Musculoskeletally Stable (IMS) position stabilization splint therapy for TMD patients using Fricton index, cone beam computed tomography (CBCT) and surface-Electromyogram (sEMG). Methods: In this study, we enrolled 31 TMD patients (ranging from 18 to 26 years old, including 7 males and 24 females), first Fricton index was used to evaluate the clinical curative effect of TMD with the treatment of IMS stabilization splint; then CBCT was used to observe the TMJ condylar position changes of TMD before and after the treatment of IMS stabilization splint; finally sEMG was used to observe the changes of electromyography of anterior temporalis (AT) and masseter muscles (MM) of TMD before and after the treatment of IMS stabilization splint. Results: The course of treatment was 6–8 months, with an average of 7.6 months. After the IMS stabilization splint treatment, TMD symptoms relieved, especially in pain, mandibular movement disorder, but still slightly inferior in the treatment of joint noise. And there was a statistically significant difference in the anterior and inner joint space, the condyle had the tendency of moving forward and outward. AT presented reduction significantly of EMG value at rest position after treatment. Conclusions: IMS stabilization splint is a therapeutic reversible treatment for TMD, especially for pain and mandibular movement disorder; it produces effects of forward and outward condylar movement and elimination of the masticatory muscles antagonism. [ABSTRACT FROM AUTHOR]

The article discusses a surgical procedure called Fronto-Orbital Advancement and Anterior Calvarial Remodeling for Trigonocephaly, focusing on cranio-orbital deformities and their management. The surgery involves various steps such as raising flaps, harvesting bone, and fixing bones in an advanced position. The outcome of the surgery was successful, with the patient showing good cosmetic correction and no neurological deficits postoperatively. The article emphasizes the importance of preoperative imaging, detailed surgical planning, and careful execution of the procedure for optimal results in correcting craniosynostosis. [Extracted from the article]

Background: In patients with facial nerve palsy, reconstruction using the facial nerve as a force source can lead to spontaneous laughter. However, reconstruction using the masseter nerve of the trigeminal nerve branch as the force source can also produce involuntary laughter independent of occlusal movements. This process remains largely unexplored. Material and Methods: Surface electromyography was performed simultaneously on six channels of the bilateral zygomatic major, temporalis, and masseter muscles for seven facial expressions. There were 10 subjects for a total of 20 sides on both sides. Ratings were scored on a 4-point scale, with a score of 2 or higher and an average score of 1.5 or higher considered valid muscle contraction. Results: Effective contraction of the temporalis muscle was observed in more than one-third of the upper facial expression movements. In voluntary and involuntary laughter, effective contractions of both the temporalis and masseter muscles were observed in some cases. Conclusion: The present results indicate that the masticatory muscles are also active in conjunction with the facial muscles during facial expression muscle activity and suggest that co-relating activity between mimic muscles and the masticatory muscle may be one of the factors that contribute to the development of involuntary laughter in facial nerve palsy reconstruction in which the trigeminal nerve is the source of power. [ABSTRACT FROM AUTHOR]

Background: Sarcopenia, defined as the loss of skeletal muscle mass, has been associated with a worse functional outcome after stroke. Measurement of temporal muscle thickness (TMT) has been introduced as an easily obtainable surrogate marker to identify patients with sarcopenia. Our study aims to investigate the correlation between pre-stroke sarcopenia, measured by TMT assessment, and functional outcome in patients treated with revascularization procedures for acute ischemic stroke. Methods: We included consecutive adult patients who underwent thrombolysis, endovascular thrombectomy or both for acute ischemic stroke at our Centre from January 2020 to June 2022. Besides collecting baseline clinical and neuroradiological features, TMT was measured on brain computed tomography scans according to a standardized protocol. Modified Rankin Scale (mRS) scores at 3 months represented the main endpoint of functional outcome. Results: A total of 261 patients were available for the analysis. In univariate models, patients with excellent outcomes (mRS = 0–1) were younger, had higher TMT values and lower pre-event disability and stroke severity. In multivariate models higher TMT values resulted independently associated with reduced mortality (Odds Ratio 0.708, 95% Confidence Interval 0.538–0.930, p = 0.013). Age, diabetes, brain bleeding events and stroke severity were found to be predictors of mortality, too. Conclusions: Our retrospective analysis shows that in patients who underwent revascularization treatments for ischemic stroke TMT is as an independent predictor of survival easily obtainable from the baseline CT scan. Further investigation is required to confirm the role of sarcopenia assessment and TMT measurement in the prognostication toolkit of this disease. [ABSTRACT FROM AUTHOR]

AIM: The present study was undertaken to evaluate and compare muscle activity after the treatment with rigid and flexible fixed functional appliance. MATERIAL AND METHOD: The study was conducted on 14 skeletal Class II malocclusion patients in the age group of 13–17 years, divided into two groups comprising 7 patients in each group. Group I was treated with a rigid fixed functional appliance (MPA IV), and Group II was treated with a flexible fixed functional appliance (Churro Jumper). Masseter and anterior temporalis muscle activities were recorded using needle electromyography (EMG) at postural rest, saliva swallowing, and clenching during five intervals (T0 to T4) during fixed functional appliance treatment. Unpaired t -test, Mann–Whitney U, and Wilcoxon sign rank test were applied for statistical analysis, and a P value of <.05 was considered statistically significant. RESULTS: Group I (MPA IV) showed a significant increase in EMG activity during postural rest position (P = 0.003, P = 0.001), swallowing (P = 0.013, P = 0.005), and clenching (P = 0.001, P = 0.002) in masseter and anterior temporalis muscle, respectively. Group II (Churro jumper) also showed a significant increase in EMG activity during postural rest position (P = 0.000, P = 0.000), swallowing (P = 0.001, P = 0.000), and clenching (P = 0.001, P = 0.000) in masseter and anterior temporalis muscle, respectively. CONCLUSION: Both rigid (MPA IV) and flexible (Churro Jumper) fixed functional appliances caused a significant increase in EMG activity of masseter and anterior temporalis muscle during postural rest position, swallowing, and clenching in 6 months of the observation period, but the flexible appliance (Churro Jumper) showed more significant increase. [ABSTRACT FROM AUTHOR]

Diagnosis of bruxism is challenging because not all contractions of the masticatory muscles can be classified as bruxism. Conventional methods for sleep bruxism detection vary in effectiveness. Some provide objective data through EMG, ECG, or EEG; others, such as dental implants, are less accessible for daily practice. These methods have targeted the masseter as the key muscle for bruxism detection. However, it is important to consider that the temporalis muscle is also active during bruxism among masticatory muscles. Moreover, studies have predominantly examined sleep bruxism in the supine position, but other anatomical positions are also associated with sleep. In this research, we have collected EMG data to detect the maximum voluntary contraction of the temporalis and masseter muscles in three primary anatomical positions associated with sleep, i.e., supine and left and right lateral recumbent positions. A total of 10 time domain features were extracted, and six machine learning classifiers were compared, with random forest outperforming others. The models achieved better accuracies in the detection of sleep bruxism with the temporalis muscle. An accuracy of 93.33% was specifically found for the left lateral recumbent position among the specified anatomical positions. These results indicate a promising direction of machine learning in clinical applications, facilitating enhanced diagnosis and management of sleep bruxism. [ABSTRACT FROM AUTHOR]

Purpose: Facial paralysis results from congenital or acquired facial nerve damage, leading to significant cosmetic and functional deficits. Surgical resection of parotid and midface tumors can cause facial paralysis, necessitating effective treatment strategies. This review addresses the challenge of restoring movement and function in late-stage facial paralysis, focusing on dynamic repair techniques involving nerve and muscle transplantation. Methods: The review encompasses studies on dynamic repair surgery for late facial paralysis, including techniques such as local muscle flap with pedicle transfer, vascularized nerve flap with pedicle transfer, and multiple muscle flap procedures. A systematic literature search was conducted using PubMed, Web of Science, and Google Scholar, covering studies from 2000 to 2024. Keywords included "dynamic repair", "late-stage facial paralysis", "nerve and muscle transplantation", "muscle flap", and "tendon transposition". Included were clinical studies, systematic reviews, and meta-analyses reporting surgical outcomes. Exclusion criteria included studies with insufficient data and non-peer-reviewed articles. Results: Dynamic repair techniques involving nerve and muscle transplantation are essential for treating late-stage facial paralysis. Each surgical method has strengths and limitations. The masseter muscle flap demonstrates high success rates, although it can cause horizontal tension and jaw contour issues. The temporalis muscle flap is effective for smile restoration but may lead to temporal concavity. The gracilis muscle flap is widely used, especially with dual nerve innervation, showing high success in spontaneous smiles but requiring a longer recovery period. The latissimus dorsi flap is effective but can cause edema and shoulder issues. The serratus anterior free flap offers flexibility with precise vector positioning but may not achieve adequate lip elevation and can cause cheek swelling. Combined multi-flap surgeries provide more natural facial expressions but increase surgical complexity and require advanced microsurgical skills. Conclusions: Dual nerve innervation shows promise for restoring spontaneous smiles. One-stage surgery offers faster recovery and reduced financial burden. Comprehensive patient evaluation is crucial to select the most suitable surgical method. Dynamic repair techniques involving nerve and muscle transplantation provide effective solutions for restoring function and aesthetics in late-stage facial paralysis. Future research should focus on long-term outcomes, patient satisfaction, and standardizing surgical protocols to optimize treatment strategies. [ABSTRACT FROM AUTHOR]

Background: Surgical dissection and partial detachment of the temporalis muscle during neurosurgical procedures might result in a temporal depression known as "temporal hollowing". Reconstructive procedures to correct this condition include the implantation of synthetic materials (e.g., hydroxyapatite, methacrylate or polyethylene), injection of autologous fat or fillers as well as the use of flaps (e.g., temporo-parietal local flap and latissimus dorsi free flap). However, none of these techniques proved to be an ideal option due to a high complication rate or need for invasive and complex surgery. Adipo-dermal grafts are autologous; the resorption rate seems to be limited and the complexity of the procedure is minor. Moreover, autologous fat grafting can be performed to enhance the final outcome by correcting residual contour deformities. Methods: In this series of five patients, an institutional experience is presented using multi-layered adipo-dermal grafts harvested from the supra-pubic area for the restoration of volume and contour in post-surgical temporal hollowing. During the last follow-up, patients were asked to express their satisfaction, which was assessed by a survey. Results: this approach demonstrates a marked improvement in temporal hollowing associated with a low complication rate and good patient satisfaction. Conclusions: the aim of this consecutive case series is to emphasize the effectiveness of this surgical technique as one of the options to address temporal hollowing. [ABSTRACT FROM AUTHOR]

Background: Tension-type headache (TTH) is the most prevalent primary headache. Pressure pain thresholds (PPTs) reflect the pressure pain sensitivity of the tissues. Women with TTH have showed greater pressure hypersensitivity in some muscles compared to men. The aim of this study was to compare the PPTs from myofascial trigger points in cervical and cranial muscles which might contribute to headaches between men and women with TTH. Methods: An observational and correlation cross-sectional study was performed. PPTs were evaluated bilaterally and compared between men and women in the following muscles: upper trapezius, splenius capitis and cervicis, semispinalis, rectus capitis posterior major, obliquus capitis superior and inferior, occipitofrontalis posterior and anterior, temporalis, masseter, clavicular and sternal head of sternocleidomastoid, zygomaticus major, and levator scapulae. The mean PPT was calculated as well. Results: Significant differences showing lower PPTs in women compared to men were found in the mean PPT (p = 0.000) and in all the points except in the left clavicular head of the sternocleidomastoid (p = 0.093) and in the left masseter (p = 0.069). Conclusions: Lower PPTs from myofascial trigger points in cervical and cranial muscles, which might contribute to headaches, were observed in women compared to men with TTH. The mean PPT was also lower in women than in men, suggesting the need for gender-specific approaches in the treatment of TTH. [ABSTRACT FROM AUTHOR]

Background: Electromyographic activity (EMG) of masticatory muscles during wakefulness is understudied. It is unclear if single channel ambulatory EMG devices are sensitive enough to detect masticatory muscle activity (MMA) during wakefulness. Objectives: To compare the MMA of various oral tasks recorded with a single channel EMG device ((Grindcare4‐datalogger Prototype device) (GC4‐β)) and a conventional EMG (cEMG) device. Methods: EMG activity of 30 standardised oral tasks was recorded unilaterally from the masseter and anterior temporalis muscle in 24 healthy volunteers using GC4‐β and a cEMG device. To compare the EMG data, signal‐to‐noise ratios (SNR) were calculated as a way to normalise EMG activity across tasks. Analysis of variance was used to compare the SNR between the devices, muscles and oral tasks. Results: SNR measured from GC4‐β was overall significantly higher than the cEMG device (p =.001). The SNR for maximum voluntary contraction (MVC) was significantly higher than all other tasks (p <.001). SNR for temporalis with GC4‐β was significantly higher for MVC, hard food, soft food, gum chewing (dominant side), rhythmic clenching and upper lip biting compared to the cEMG device (p <.021). The SNR for masseter with GC4‐β was significantly higher for hard food and gum chewing (dominant side), rhythmic clenching, rhythmic biting of an object and yawning compared to the cEMG device (p <.022). Conclusions: This study provides novel insight into the EMG patterns of numerous oral tasks enhancing knowledge of physiological differences between the masticatory muscles. Further, single channel EMG devices can effectively measure the EMG activity of various oral tasks during wakefulness. [ABSTRACT FROM AUTHOR]

Background The use of clear aligners is becoming more common for aesthetic orthodontic treatment, but there are still concerns about how they affect mastication biomechanics in the short and long term. The clear aligners treatment (CAT) mechanism changes the position of the mandible and maxilla, especially impacting the masseter muscle. Surface electromyography (sEMG) proves to be a useful method to evaluate masticatory muscle activity (MMA). Objectives To analyze the effect of clear aligners treatment on alterations in masticatory muscles (masseter, temporalis) using surface electromyography. Search methods Five databases (PubMed, Web of Science, SCOPUS, Cochrane Library, and Google Scholar) were searched up to March 2024. Selection criteria Studies in which MMA was evaluated after the installation of orthodontic clear aligners. Data collection and analysis Screening, data extraction, and quality assessments were performed by four investigators independently. The data, which evaluated temporalis and masseter muscle characteristics during CAT using surface electromyography, was extracted, and the quality of the studies was evaluated. The risk of bias was assessed using the Newcastle-Ottawa Scale (NOS). Results Six studies (two prospective cohort studies, three observational longitudinal studies, and one observational longitudinal case–control study) with low and moderate risk of bias were included in the qualitative synthesis. Six of these were also included in the meta-analysis. Our study investigated the dynamics of masseter and temporalis muscle activity during CAT. The results show that during maximal voluntary clenching, the masseter muscle demonstrated a significant initial increase (P  < .05) followed by a subsequent non-significant decrease. It also showed that submaximal voluntary clenching consistently exhibited a significant reduction in muscle activity throughout the study period (P  < .01). Assessment of muscle activity at the mandibular resting position revealed a variety of responses, with some participants showing a significant increase while others exhibited non-significant changes (P  < .05, P  > .05, respectively). However, the meta-analysis showed a non-significant difference in measuring masseter and temporalis muscles activity during CAT. Conclusions Based on existing evidence, it is reasonable to conclude that CAT affected MMA. During maximal voluntary clenching, masseter muscle activity initially increased but later decreased, while temporalis muscle activity showed mixed results. Submaximal voluntary clenching revealed a consistent decrease in muscle activity over time. Mandibular resting position assessments showed both increases and no significant changes in muscle activity. However, the existing literature is insufficient to draw concrete conclusions; therefore, well-conducted further research is needed to confirm this statement. Registration This systematic review and meta-analysis were registered in the International Prospective Register of Systematic Reviews (PROSPERO CRD42024522231). [ABSTRACT FROM AUTHOR]

This study aimed to predict dental freeway space by examining the clinical history, habits, occlusal parameters, mandibular hard tissue movement, soft tissue motion, muscle activity, and temporomandibular joint function of 66 participants. Data collection involved video-based facial landmark tracking, mandibular electrognathography, surface electromyography of mandibular range of motion, freeway space, chewing tasks, phonetic expressions, joint vibration analysis, and 3D jaw scans of occlusion. This resulted in a dataset of 121 predictor features, with freeway space as the target variable. Six models were trained on synthetic data ranging from 500 to 25,000 observations, with 65 original observations reserved for testing: Linear Regression, Random Forest, CatBoost Regressor, XGBoost Regressor, Multilayer Perceptron Neural Network (MPNN), and TabNet. Explainable AI indicated that key predictors of freeway space included phonetics, resting temporalis muscle activity, mandibular muscle activity during clenching, body weight, mandibular hard tissue lateral displacements, and dental arch parameters. CatBoost excelled with a test error of 0.65 mm using 5000 synthetic data points, while a refined MPNN achieved the best performance with 25,000 synthetic data points and 121 unique predictors, yielding an absolute error of 0.43 mm on the 65 original observations. [ABSTRACT FROM AUTHOR]

The INSPIRE randomized clinical trial demonstrated that a high protein diet (HPRO) combined with neuromuscular electrical stimulation (NMES) attenuates muscle atrophy and may improve outcomes after aneurysmal subarachnoid hemorrhage We sought to identify specific metabolites mediating these effects. Blood samples were collected from subjects on admission prior to randomization to either standard of care (SOC; N = 12) or HPRO + NMES (N = 12) and at 7 days. Untargeted metabolomics were performed for each plasma sample. Sparse partial least squared discriminant analysis identified metabolites differentiating each group. Correlation coefficients were calculated between each metabolite and total protein per day and muscle volume. Multivariable models determined associations between metabolites and muscle volume. Unique metabolites (18) were identified differentiating SOC from HPRO + NMES. Of these, 9 had significant positive correlations with protein intake. In multivariable models, N-acetylleucine was significantly associated with preserved temporalis [OR 1.08 (95% CI 1.01, 1.16)] and quadricep [OR 1.08 (95% CI 1.02, 1.15)] muscle volume. Quinolinate was also significantly associated with preserved temporalis [OR 1.05 (95% CI 1.01, 1.09)] and quadricep [OR 1.04 (95% CI 1.00, 1.07)] muscle volume. N-acetylserine and β-hydroxyisovaleroylcarnitine were associated with preserved temporalis or quadricep volume. Metabolites defining HPRO + NMES had strong correlations with protein intake and were associated with preserved muscle volume. [ABSTRACT FROM AUTHOR]

Quantitative muscle ultrasound (QMUS) is potentially valuable as a diagnostic tool in central neurological disorders, as it provides information about changes in muscle architecture. This study aimed to investigate whether ultrasound images of the submental and masticatory muscles in children with spastic cerebral palsy (CP) differ from those obtained in a reference group, and whether observed ultrasound abnormalities differ between subgroups of children with different Eating and Drinking Ability Classification System (EDACS) levels to support its construct validity.A prospective cohort study was conducted in 25 children with spastic CP aged 3-18 years. QMUS of selected muscles was performed. Muscle thickness and echogenicity in the CP group were compared to previously collected reference values, and between different EDACS levels within the CP group.Median echogenicity of all muscles was significantly higher in children with CP than in healthy controls. The temporalis muscle was significantly thinner in the CP group. There were no differences in muscle thickness or echogenicity between EDACS levels.QMUS is able to detect abnormal architecture of submental and masticatory muscles in children with spastic CP, but the interpretation of abnormalities in relation to the severity of mastication and swallowing problems needs further investigation. [ABSTRACT FROM AUTHOR]

This article discusses the challenges involved in rehabilitating worn dentition, including preserving the health of natural tissues, restoring functionality, and meeting aesthetic desires. The article emphasizes the importance of planning and customization in successful rehabilitation, as well as the need to identify and eliminate risk factors. A case report is presented, detailing a step-by-step approach using the Chronological Reconstruction Concept, which involves a 13-appointment procedure divided into three phases. The article concludes by highlighting the success of the treatment and the importance of meticulous planning and phased reconstruction in managing complex dental cases. [Extracted from the article]

Purpose: We prospectively assessed the effects of botulinum toxin type-A (BTX-A) on primary and secondary outcomes in a population of refractory myofascial pain and dysfunction patients when conservative management had proven ineffective. Methods: In this study, 26 patients with masticatory myofascial pain, who were refractory to conservative management, were enrolled prospectively to evaluate responses following the injection of botulinum toxin-A (BTX-A). Masseter muscles were injected with 30 units BTX-A and 20 units into the temporalis muscles. Pain, tenderness to palpation, and oral function were evaluated subjectively using a visual analog scale (VAS). Objective outcomes of maximal mouth opening (MMO) and reduction in total facial width after injection with BTX-A were measured. Participants were reassessed at 1-week, 1, 3, and 6-month intervals. A linear mixed-effect model was employed to assess the level of correlation (dependence) among different outcomes. Results: Administration of BTX-A had a significant strong positive correlation with the reduction of pain (Phi = 0.641, P < 0.0005); significant strong positive correlation with increase in oral function (Phi = 0.738, P < 0.0015); significant strong positive correlation with increase in maximal mouth opening (Phi = 0.645, P < 0.0085); significant strong positive correlation with tenderness to palpation (Phi = 0.510, P < 0.0011); and significant strong positive correlation with reduction in facial width (Phi = 0.565, P < 0.0001). Conclusion: The results from this study demonstrate that BTX-A administration may provide a safe and effective means to treat myofascial pain from hyperfunctioning masticatory muscles. It is not recommended to replace first-line treatment but may provide relief from chronic facial pain if properly administered in patients where standard conservative management has been unsuccessful. [ABSTRACT FROM AUTHOR]

Objectives: Periodontitis is one of the most common chronic inflammatory diseases. It causes changes in the biting abilities of individuals. However, periodontal treatment has positive effects on masticatory function. The aim of this study is to determine the effect of periodontitis and periodontal treatment on masticatory abilities by measuring masseter and temporal muscle thicknesses with ultrasonography before and after periodontal treatment in chronic periodontitis patients. Methods: The patients included in the study were determined by clinical and radiological examination. The thickness of the masseter and temporal muscles of the patients were measured by ultrasonography. Periodontal measurements and treatments of the patients were completed by a single physician. IBM SPSS 20.0 (IBM Corp., Armonk, NY) statistical program was used for statistical analysis. Results: A statistically significant difference was found between the values of periodontal measurements before and after treatment (p<0.05). In the ultrasonography measurements of the thickness of masseter and anterior temporal muscles, a statistically significant increase was observed in both rest and contraction values at all time intervals (p<0.05). Muscle thicknesses of male patients were higher than female patients. Conclusions: Periodontitis negatively affects the masticatory performance of individuals. Chronic periodontitis patients should be referred for periodontal treatment without wasting time. [ABSTRACT FROM AUTHOR]

The morphology and biomechanics of infant crania undergo significant changes between the pre- and post-weaning phases due to increasing loading of the masticatory system. The aims of this study were to characterize the changes in muscle forces, bite forces and the pattern of mechanical strain and stress arising from the aforementioned forces across crania in the first 48 months of life using imaging and finite element methods. A total of 51 head computed tomography scans of normal individuals were collected and analysed from a larger database of 217 individuals. The estimated mean muscle forces of temporalis, masseter and medial pterygoid increase from 30.9 to 87.0 N, 25.6 to 69.6 N and 23.1 to 58.9 N, respectively (0–48 months). Maximum bite force increases from 90.5 to 184.2 N (3–48 months). There is a change in the pattern of strain and stress from the calvaria to the face during postnatal development. Overall, this study highlights the changes in the mechanics of the craniofacial system during normal development. It further raises questions as to how and what level of changes in the mechanical forces during the development can alter the morphology of the craniofacial system. [ABSTRACT FROM AUTHOR]

Purpose: Skull base reconstruction is one of the most difficult reconstructive surgical procedures. Due to its complexity, most surgeons have modified the reconstruction methods to minimize the postoperative complications and mortality rate. In the past, flap surgery was not usually performed, but it has recently become more common due to advances in medicine. In this study, we analyzed successful flap surgery methods in skull base reconstruction for large cranial-nasal communications. Methods: Patients who underwent skull base reconstruction from April 2015 to January 2024 were eligible for this study. Of these patients, we included those who underwent reconstruction using a volumetric flap. Reconstructions that only used the conventional galeal flap, allograft skin, or bone substitute were excluded. The reconstruction methods used local flaps and free flaps. Results: In total, 22 patients underwent skull base reconstruction. The most frequently used local flap was the bilateral reverse temporalis muscle flap (seven of 11 cases), and the most frequent free flap was the anterior lateral thigh flap (10 of 11 cases). Other local flap operations used the modified temporalis muscle flap and scalp flap. A rectus myocutaneous flap was also used. There were no cases of flap necrosis. Conclusion: Flap surgery is needed for skull base reconstruction in patients with large cranial-nasal communications. As long as the flap volume is large enough to block and fill the defect, either a local flap or a free flap can be used for reconstruction. [ABSTRACT FROM AUTHOR]

The temporal fascia is a double lamina sandwiching a thick fat layer above the zygomatic bony arch. To characterize each lamina, their developmental processes were examined in fetuses. We observed histological sections from 22 half-heads of 10 mid-term fetuses at 14–18 weeks (crown-rump length, 95–150 mm) and 12 near-term fetuses at 26–40 weeks (crown-rump length, 215–334 mm). The superficial lamina of the temporal fascia was not evident at mid-term. Instead, a loose subcutaneous tissue was attached to the thin, deep lamina of the temporal fascia covering the temporalis muscle. At near-term, the deep lamina became thick, while the superficial lamina appeared and exhibited several variations: i) a monolayered thick membrane (5 specimens); ii) a multi-layered membranous structure (6) and; iii) a cluster of independent thick fasciae each of which were separated by fatty tissues (1). In the second and third patterns, fatty tissue between the two laminae was likely to contain longitudinal fibrous bands in parallel with the deep lamina. Varying proportions of the multi-layered superficial lamina were not attached to the zygomatic arch, but extended below the bony arch. Whether or not lobulation or septation of fatty tissues was evident was not dependent on age. The deep lamina seemed to develop from the temporalis muscle depending on the muscle contraction. In contrast, the superficial lamina developed from subcutaneous collagenous bundles continuous to the cheek. Therein, a difference in development was clearly seen between two categories of the fasciae. [ABSTRACT FROM AUTHOR]

Background: While mastoid obliteration techniques have received much attention in decreasing the disadvantages associated with the resultant mastoid cavity from canal wall down procedures, techniques for an anatomically normal looking ear canal reconstruction to increase the feasibility of hearing aid fitting are less commonly discussed as an alternative. Methods: Our mastoidoplasty technique basically utilises an inferiorly based periosteal flap with or without temporalis muscles and fascia to obliterate the epitympanum and reconstruct the external auditory canal (EAC). Stay sutures are used to keep them in place. For larger cavities, demineralized bone matrix (DBM) is used to obliterate the mastoid cavity and support the neo-EAC. Conclusions: The concept of our mastoidoplasty potentially provides a very useful alternative in recreating a near normal ear canal anatomy avoiding cavity problems as well as facilitating hearing aid fitting with canal type hearing aids after canal wall down mastoidectomy. [ABSTRACT FROM AUTHOR]

Primate mandibular morphology is often associated with jaw functionality of the masticatory complex in the context of variation in diets. Recent research into the disparities between the diet and jaw functionality in male and female hominoids is inconclusive and suggests that sexual dimorphism in the mandible may be influenced by external factors such as temporalis and masseter muscle morphology, which in turn may be influenced by sexual selection. As the muscles associated with mastication (i.e., the type of chewing exhibited by primates and other mammals) encompass the mandible as well as the neurocranium, including the sagittal crest among some individuals, this study investigates sex‐specific associations between regions of the mandibular ramus and neurocranium associated with mastication in a dentally mature sample of Gorilla and Pongo. A total of four cranial and mandibular variables were measured in two Gorilla taxa (Gorilla gorilla gorilla and Gorilla beringei graueri) and one Pongo taxon (Pongo pygmaeus pygmaeus) (n = 220). For all three taxa, we investigate (a) whether the degree of sexual dimorphism in cranial regions associated with sagittal cresting (sagittal crest size (SCS) and temporalis muscle attachment area (TMAA)) is proportional to the degree of mandibular ramus area (MRA) and coronoid process height (CPH) sexual dimorphism, (b) whether there are sex differences in scaling relationships between TMAA and MRA, and (c) whether there are sex differences in the strength of association between TMAA and CPH. We show that for G. g. gorilla, variables associated with sagittal cresting show higher sexual dimorphism values than our two mandibular ramus variables, which is not the case for G. b. graueri or for P. p. pygmaeus. All three taxa show similar sex‐specific scaling relationships between TMAA and MRA, where for males this relationship does not diverge from isometry, and for females there is a negative allometric relationship. Our findings also show intraspecific sex differences in allometric slopes between MRA and TMAA for all three taxa. Only G. g. gorilla shows a significant association between TMAA and CPH, which is observed in both sexes. Although there are some statistical associations between the cranial and mandibular regions associated with mastication, our results show that among male gorillas and orangutans, patterns of variation in the sagittal crest, TMAA, mandibular ramus and the coronoid process cannot be explained by the muscle attachment hypothesis alone. These findings have implications surrounding the associations between social behaviour and the morphology of the craniofacial complex. [ABSTRACT FROM AUTHOR]

Background: Data from patients with post‐ablative dural defects reconstructed using a free temporalis muscle fascia graft (FTFG) after resection of anterior or central skull base tumors were retrospectively analyzed. Methods: The primary predictor and outcome variables were the reconstructive methods for dural repair and postoperative cerebrospinal fluid (CSF) leakage rate, respectively. Results: Eighty patients were included, and 94 postoperative dural reconstructions were performed using FTFG. The postoperative CSF leakage rate was 3.19%. The postoperative CSF leakage rates did not significantly differ between open and endonasal endoscopic surgeries (1.92% vs. 4.88%; p > 0.05). In cases completed using the endonasal endoscopic approach, the postoperative CSF leakage rate was significantly associated with the intraoperative CSF leak flow (p < 0.05). Conclusions: Post‐ablative dural defect reconstruction using FTFG resulted in low postoperative CSF leakage and complication rates comparable to those of free fascia lata graft from available literature. [ABSTRACT FROM AUTHOR]

Sarcopenia, characterized by progressive muscle loss and functional decline, poses significant risks, including falls, impaired daily activities, and increased mortality. We developed Allgeun, a novel device that measures handgrip strength, muscle mass, and physical performance. This study aimed to investigate whether temporal muscle thickness (TMT) could be used as a sarcopenia marker and to evaluate the usability of Allgeun. This prospective study enrolled 28 participants without medical or neurological disorders. They underwent three-dimensional T1-weighted imaging using a 3 Tesla magnetic resonance imaging scanner. TMT was measured based on T1-weighted images by a board-certified neuroradiologist. Allgeun was used to measure the following three key components of sarcopenia: muscle strength (handgrip strength), muscle mass (calf and thigh circumference), and physical performance (five times the chair stand test). Correlation analysis was conducted between TMT and the results of the handgrip strength, calf and thigh circumferences, and chair stand tests. There were moderate positive correlations between TMT and calf circumference (r = 0.413, p = 0.029), thigh circumference (r = 0.486, p = 0.008), and handgrip strength (r = 0.444, p = 0.018). However, no significant correlation was observed between TMT and physical performance (r = −0.000, p = 0.998). Our findings underscore TMT's potential as an indicator of sarcopenia, particularly regarding muscle mass and strength. Additionally, we demonstrated that the new device, Allgeun, is useful for screening and diagnosing the severity of sarcopenia. [ABSTRACT FROM AUTHOR]

Orofacial pain can significantly affect physical, psychological, and overall quality of life. This study aimed to compare the effectiveness of combining photobiomodulation (PBM) with orofacial myofunctional therapy (OMT) in managing orofacial pain disorders. An electronic search of randomized controlled trials in electronic databases was performed until March 2024. Randomized controlled trials (RCTs) focusing on PBM and OMT for the management of orofacial pain were included. Risk of bias across individual studies was performed using the Cochrane risk of bias tool for interventions. A total of 10 RCTs were included, out of which 7 RCTs revealed that the combined approach of PBM and OMT had a more pronounced impact on diminishing pain and enhancing functional activity in patients with orofacial disorders. One study reported significant increases in pressure pain threshold for TMJ, masseter, and anterior temporalis muscles at both sides in the post-treatment compared with the pre-treatment in both groups. The risk of bias was low in 7, moderate in 2, and high in 1 study. The efficacy of a combined modality treatment of PBM with OMT for orofacial pain disorder shows promising results. However, further randomized controlled trials with extended follow-up periods standardized PBM and OMT parameters are warranted to obtain firm conclusions. [ABSTRACT FROM AUTHOR]

Describe a new, safe, technique that uses titanium mesh to partially cover skull defects immediately after decompressive craniectomy (DC). This study is a retrospective review of 8 patients who underwent DC and placement of a titanium mesh. The mesh partially covered the defect and was placed between the temporalis muscle and the dura graft. The muscle was sutured to the mesh. All patients underwent cranioplasty at a later time. The study recorded and analyzed demographic information, time between surgeries, extra-axial fluid collections, postoperative infections, need for reoperation, cortical hemorrhages, and functional and aesthetic outcomes. After craniectomy, all patients underwent cranioplasty within an average of 112.5 days (30–240 days). One patient reported temporalis muscle atrophy, which was the only complication observed. During the cranioplasties, no adhesions were found between temporalis muscle, titanium mesh, and underlying dura. None of the patients showed complications in the follow-up computerized tomography scans. All patients had favorable aesthetic and functional results. Placing a titanium mesh as an extra step during DC could have antiadhesive and protective properties, facilitating subsequent cranioplasty by preventing adhesions and providing a clear surgical plane between the temporalis muscle and intracranial tissues. This technique also helps preserve the temporalis muscle and enhances functional and aesthetic outcomes postcranioplasty. Therefore, it represents a safe alternative to other synthetic anti-adhesive materials. Further studies are necessary to draw definitive conclusions and elucidate long-term outcomes, however, the results obtained hold great promise for the safety and efficacy of this technique. [ABSTRACT FROM AUTHOR]

Simple Summary: Temporal muscle thickness has become an interesting parameter in recent neuro-oncological research due to promising results regarding the estimation of patients' prognosis. The aim of our study was to assess its usefulness in terms of estimating prognosis after the surgical resection of brain metastases compared to functional scales. This research did not confirm previously published data postulating a significant influence of thicker temporal muscle on patient survival, but proved no association with better outcomes after neurosurgical therapy. Metastases are the most frequent intracranial malignant tumors in adults. While Karnofsky Performance Status (KPS) and Clinical Frailty Scale (CFS) are known to have significant impact on overall survival (OS), temporal muscle thickness (TMT) has been postulated to be a promising new parameter to estimate prognosis. Patients who received a resection of one to three brain metastases in our institution were included. Temporal muscle thickness was measured in preoperative MRI scans according to a standardized protocol. In 199 patients, the mean TMT was 7.5 mm (95CI 7.3–7.7) and the mean OS during follow-up was 31.3 months (95CI 24.2–38.3). There was no significant correlation of TMT and preoperative or follow-up CFS and KPS. While CFS and KPS did significantly correlate with OS (p < 0.001 for each), no correlation was demonstrated for TMT. CFS showed a superior prognostic value compared to KPS. TMT failed to show a significant impact on OS or patient performance, whereas the clinical scales (KPS and CFS) demonstrate a good correlation with OS. Due to its superiority over KPS, we strongly recommend the use of CFS to estimate OS in patients with brain metastases. [ABSTRACT FROM AUTHOR]

Simple Summary: This study aimed to analyse morphological parameters related to the bite apparatus in representatives of seven families of captive animals. Thirty-three measurements were taken of the skull, mandible, and surfaces of the masseter and temporalis muscles. Some were used to calculate the bite force on the maxillary canine and molar teeth. A high correlation between bite force and animal size was confirmed. The bending strength of the upper canines was determined using their lateromedial and anteroposterior dimensions. The aim of this study was to analyse the bite forces of seven species from three carnivore families: Canidae, Felidae, and Ursidae. The material consisted of complete, dry crania and mandibles. A total of 33 measurements were taken on each skull, mandible, temporomandibular joint, and teeth. The area of the temporalis and masseter muscles was calculated, as was the length of the arms of the forces acting on them. Based on the results, the bite force was calculated using a mathematical lever model. This study compared the estimated areas of the masticatory muscles and the bending strength of the upper canines among seven species. A strong correlation was found between cranial size and bite force. The results confirmed the hypothesis that the weight of the animal and the size of the skull have a significant effect on the bite force. [ABSTRACT FROM AUTHOR]

Abstract This study used ultrasonography to compare the thickness and cross-sectional area of the masticatory muscles in patients with temporomandibular joint arthralgia and investigated the differences according to sex and the co-occurrence of headache attributed to temporomandibular disorders (HATMD). The observational study comprised 100 consecutive patients with TMJ arthralgia (71 females and 29 males; mean age, 40.01 ± 17.67 years) divided into two groups: Group 1, including 86 patients with arthralgia alone (60 females; 41.15 ± 17.65 years); and Group 2, including 14 patients with concurrent arthralgia and HATMD (11 females; 33.00 ± 16.72 years). The diagnosis of TMJ arthralgia was based on the diagnostic criteria for temporomandibular disorders. The parameters of the masticatory muscles examined by ultrasonography were subjected to statistical analysis. The pain area (2.23 ± 1.75 vs. 5.79 ± 2.39, p-value = 0.002) and visual analog scale (VAS) score (3.41 ± 1.82 vs. 5.57 ± 12.14, p-value = 0.002) were significantly higher in Group 2 than in Group 1. Muscle thickness (12.58 ± 4.24 mm) and cross-sectional area (4.46 ± 2.57 cm2) were larger in the masseter muscle than in the other three masticatory muscles (p-value

Abstract To compare masticatory muscle thickness in patients with temporomandibular disorders (TMDs) during rest and clenching, and by body position, using ultrasonography. This prospective study included 96 patients with TMD (67 females, 29 males; mean age: 40.41 ± 17.88 years): group 1, comprising 66 patients with TMD without bruxism (TMD_nonbruxer), and group 2, comprising 30 patients with concurrent TMD and bruxism (TMD_bruxer). In patients with TMD, bruxism was correlated with the presence of tinnitus, muscle stiffness, sleep problems, psychological stress, and restricted mouth opening. The masseter muscle significantly thickened during clenching (11.16 ± 3.03 mm vs 14.04 ± 3.47 mm, p

Introduction: Dirofilariasis, a parasitic infection typically affecting animals, occasionally presents in humans, transmitted through mosquito bites. This article explores an unusual case of dirofilariasis affecting the temporalis muscle, a rare occurrence. With 40 identified Dirofilaria species, human infections are primarily attributed to Dirofilaria repens and Dirofilaria immitis, causing pulmonary and subcutaneous lesions. While deep tissue infections are exceptionally rare, we present a unique case in a 15-year-old girl. Case Report: The patient exhibited a 3-month history of a slowly growing swelling in the left temporal region, accompanied by intermittent pain and limited jaw movement. Initial differential diagnoses included benign tumors, cysts, or abscesses. Ultrasound revealed a hypoechoic mass, leading to surgical excisional biopsy. Histopathological examination confirmed Dirofilaria, prompting a combination of antiparasitic medication and surgical intervention. Discussion: Dirofilariasis in deep tissues, especially muscles, is uncommon. Diagnosis challenges arise due to its rarity and similarity to other conditions. Imaging may not be specific, necessitating histopathological examination. Treatment involves antiparasitic medications like ivermectin, supplemented with surgery in specific cases. Our patient's favorable outcome underscores the importance of early recognition and a multidisciplinary approach for effective management. [ABSTRACT FROM AUTHOR]

This study used ultrasonography to compare the thickness and cross-sectional area of the masticatory muscles in patients with temporomandibular joint arthralgia and investigated the differences according to sex and the co-occurrence of headache attributed to temporomandibular disorders (HATMD). The observational study comprised 100 consecutive patients with TMJ arthralgia (71 females and 29 males; mean age, 40.01 ± 17.67 years) divided into two groups: Group 1, including 86 patients with arthralgia alone (60 females; 41.15 ± 17.65 years); and Group 2, including 14 patients with concurrent arthralgia and HATMD (11 females; 33.00 ± 16.72 years). The diagnosis of TMJ arthralgia was based on the diagnostic criteria for temporomandibular disorders. The parameters of the masticatory muscles examined by ultrasonography were subjected to statistical analysis. The pain area (2.23 ± 1.75 vs. 5.79 ± 2.39, p-value = 0.002) and visual analog scale (VAS) score (3.41 ± 1.82 vs. 5.57 ± 12.14, p-value = 0.002) were significantly higher in Group 2 than in Group 1. Muscle thickness (12.58 ± 4.24 mm) and cross-sectional area (4.46 ± 2.57 cm2) were larger in the masseter muscle than in the other three masticatory muscles (p-value < 0.001). When examining sex-based differences, the thickness and area of the masseter and lower temporalis muscles were significantly larger in males (all p-value < 0.05). The area of the masseter muscle (4.67 ± 2.69 vs. 3.18 ± 0.92, p-value = 0.004) and lower temporalis muscle (3.76 ± 0.95 vs. 3.21 ± 1.02, p-value = 0.049) was significantly smaller in Group 2 than in Group 1. An increase in VAS was significantly negatively correlated with the thickness of the masseter (r = − 0.268) and lower temporalis (r = − 0.215), and the cross-sectional area of the masseter (r = − 0.329) and lower temporalis (r = − 0.293). The masseter and lower temporalis muscles were significantly thinner in females than in males, and their volumes were smaller in patients with TMJ arthralgia and HATMD than in those with TMJ arthralgia alone. HATMD and decreased masseter and lower temporalis muscle volume were associated with increased pain intensity. [ABSTRACT FROM AUTHOR]

Background: Reduced clearance of cerebrospinal fluid (CSF) has been suggested as a pathological feature of Alzheimer's disease (AD). With extensive documentation in non-human mammals and contradictory human neuroimaging data it remains unknown whether the nasal mucosa is a CSF drainage site in humans. Here, we used dynamic PET with [1-11C]-Butanol, a highly permeable radiotracer with no appreciable brain binding, to test the hypothesis that tracer drainage from the nasal pathway reflects CSF drainage from brain. As a test of the hypothesis, we examined whether brain and nasal fluid drainage times were correlated and affected by brain amyloid. Methods: 24 cognitively normal subjects (≥ 65 years) were dynamically PET imaged for 60 min. using [1-11C]-Butanol. Imaging with either [11C]-PiB or [18F]-FBB identified 8 amyloid PET positive (Aβ+) and 16 Aβ- subjects. MRI-determined regions of interest (ROI) included: the carotid artery, the lateral orbitofrontal (LOF) brain, the cribriform plate, and an All-turbinate region comprised of the superior, middle, and inferior turbinates. The bilateral temporalis muscle and jugular veins served as control regions. Regional time-activity were used to model tracer influx, egress, and AUC. Results: LOF and All-turbinate 60 min AUC were positively associated, thus suggesting a connection between the brain and the nose. Further, the Aβ+ subgroup demonstrated impaired tracer kinetics, marked by reduced tracer influx and slower egress. Conclusion: The data show that tracer kinetics for brain and nasal turbinates are related to each other and both reflect the amyloid status of the brain. As such, these data add to evidence that the nasal pathway is a potential CSF drainage site in humans. These data warrant further investigation of brain and nasal contributions to protein clearance in neurodegenerative disease. [ABSTRACT FROM AUTHOR]