Temporalis Research Articles

The other face of facioscapulohumeral muscular dystrophy: Exploring orofacial weakness using muscle ultrasound.

One of the most distinct clinical features of facioscapulohumeral muscular dystrophy (FSHD) is facial weakness. It leads to diminished facial expression and functional impairments. Despite its clinical relevance, little else is known about orofacial muscle involvement. We therefore evaluated orofacial muscle involvement in a sizeable cohort of FSHD participants with muscle ultrasound. Muscle ultrasound images of the following orofacial muscles were scored visually and quantitatively: depressor anguli oris (DAO), orbicularis oris (OO), buccinator, temporalis, masseter, digastric, zygomaticus major and minor bilaterally, and the geniohyoid. Reliability analyses of both visual and quantitative evaluations were performed. Ultrasound results were correlated with other measures: the FSHD clinical score, facial weakness score, and facial function scale. We included 107 FSHD participants (male 54%; age 52 ± 14 years), of whom 92% showed signs of facial weakness. The reliability of visual ultrasound analysis varied widely (κ 0.0-1.0). Quantitative ultrasound reliability was high (intraclass correlation analysis ≥ 0.96). The DAO, buccinator, OO, temporalis, and zygomaticus minor muscles were affected most often (15%-39%). The digastric, geniohyoid, zygomaticus major, and masseter muscles were least often affected (<5%). The ultrasound compound score correlated weakly to moderately with other outcome measures used (ρ = 0.3-0.7). This study adds to the understanding of orofacial weakness in FSHD, confirming the involvement of the muscles of facial expression in FSHD using ultrasound. We showed that orofacial muscle ultrasound is feasible and reliable when quantitatively assessed. Future studies should evaluate orofacial muscle ultrasound longitudinally, alongside clinical and patient-reported facial weakness outcome measures, to assess their potential as outcome measures.

Masticatory function in growing individuals with hypohidrotic ectodermal dysplasia: A longitudinal study.

Hypohidrotic ectodermal dysplasia (HED) is a hereditary disorder with agenesis of ectodermal derivatives, causing oligodontia or anodontia. Dentures are needed to improve the patients' mastication. This study aimed at preliminarily evaluating the masticatory function changes in Chinese individuals with HED after prosthetic rehabilitation from childhood to adolescence. This longitudinal study enrolled 10 HED patients. Data were collected during childhood and adolescence, respectively. The healthy children and adolescents were recruited as the control group. The surface electromyography (EMG) of masseter (MM) and anterior temporalis (TA) muscles during clenching and chewing were recorded. The EMG activity, asymmetry index (As), activity index (Ac), and chewing cycle were analyzed. The masticatory efficiency was measured by spectrophotometry with subjective masticatory ability assessed by a questionnaire. The EMG activities and masticatory efficiency of HED patients during childhood and adolescence were mostly lower with a higher As (p < .05). The chewing process enhanced the TA activity and balanced the As of HED adolescents (p > .05). The HED adolescents showed a more prevalent TA activity (p < .05). The masticatory function of the growing HED patients was functionally inferior to the dentate individuals with a narrowed gap from childhood to adolescence.

Mechanics- and Behavior-Related Temporomandibular Joint Differences

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.

The preliminary study of the effects of individual musculoskeletally stable position in the treatment of temporomandibular disorders

BackgroundTemporomandibular 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).MethodsIn 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.ResultsThe 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.ConclusionsIMS 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.

The utility and outcomes of the temporalis muscle flap for palate reconstruction after maxillectomy for malignancy

Back groundA common pedicled facial technique in head and neck reconstruction is the TMF It can be utilised to replace missing tissues in a variety of conditions, including oral deformities of the hard and soft palate.Aim of the study was to document the utility and outcomes with the reconstruction of the palate using TM flaps following Maxillectomy For maxillary sinus malignancies MethodologyThe study included 24 patients who were operated on for cancer maxilla and eligible for maxillectomy and reconstruction of the Palate using temporalis flap. Follow-up was planned for at least 12 months postoperative. Postoperative physical and speech therapy are initiated to help improve speech and swallow outcomes and to prevent trismus ResultsThe current study included 24 cases with Maxillary sinus cancer with a mean age of 42.34±4.67. The mean operative time was 5.4±1.22 hours with no reported intraoperative bleeding or injury of important structures .No cases of facial palsy or trismus were reported while partial flap loss was reported in one case where oronasal fistula was evident. The donor site complications were minimal where seroma occurred in two patients and alopecia , wound infection and dehiscence were reported in one case each. The donor site depression was evident in 25% of cases ConclusionTMF is an excellent option for the reconstruction of many craniofacial defects, it is easy to be harvested with good blood supply with minimal postoperative complications

EP574 - Outcomes of temporalis muscle based facial reanimation surgery: A systematic review and meta-analysis

Abstract Aims Despite encouraging findings of temporalis based facial reanimation surgery without the need for nerve grafting, there remains a need for a comprehensive evaluation of the impact of temporalis based facial reanimation surgery on key outcome measures. Methods Comprehensive search in MEDLINE and Embase databases were done up to 25th February 2023. The inclusion criteria for this study focused on articles that examined facial reanimation surgery utilising the temporalis muscle. Postoperative changes in smile excursion and angle of mouth while smiling were pooled using the DerSimonian and Laird random effects model. Narrative synthesis was conducted for other outcomes including assessments of spontaneous smile, subjective evaluation of facial symmetry using validated rating tools, functional outcomes, aesthetic outcomes, and patient-reported outcomes owing to heterogeneity in reporting of outcomes. Results 24 studies were included in the analysis. Conflicting evidence was demonstrated regarding emotional smile outcomes and its definition. The pooled changes in smile excursion post-surgery was 7.06mm (95 CI 3.73-10.40, P&amp;lt;0.001; I2= 0%) and in angle of mouth while was 11.76 degree (95 CI 8.80-14.71, P&amp;lt;0.001; I2= 0%). Significant improvement was reported across validated rating scales of symmetry, functional outcomes, aesthetic outcomes, and patient-reported outcomes while superiority compared to other procedures remain inconclusive. Conclusion Overall, temporalis-based facial reanimation surgery is a promising option for addressing the negative effects of facial nerve paralysis on patients' quality of life. The study highlights the uncertainty surrounding the technique and the need for further studies.

Effectiveness of Laser Therapy in Treatment of Temporomandibular Joint and Muscle Pain.

Background/Objectives: Temporomandibular joint disorders (TMDs) express a condition derived from a broad spectrum of etiological factors and clinical manifestations. Many treatment options have been developed for TMDs; nevertheless, conservative and non-invasive approaches ought to be prioritized. Laser therapy is an effective treatment for pain management due to its non-invasive nature and capacity for tissue regeneration. This review aimed at bringing an overview of the present evidence regarding the efficiency of laser therapy on myofascial or temporomandibular joint disorders pain. Methods: The search was conducted in four electronic databases: PubMed, Web of Science, Embase, and Scopus, of studies published between January 1997 and January 2023. The following terms have been extensively searched: "laser treatment", pain management", "temporomandibular joint disorders", "masseter muscle pain", "pterygoid muscle pain", and "temporal muscle pain". The inclusion criteria were original papers, available in full text, and written in English. Cohen's Kappa coefficient was used to assess the inter-rater reliability for article selection. The methodological quality was assessed with the Cochrane Risk of Bias tool for randomized controlled trials and the National Heart, Lung, and Blood Institute's quality assessment tool for before-after studies with no control group. Results: Out of 846 identified records, 7 studies were included, of which 5 were randomized controlled trials. The inter-rater reliability for article selection showed an almost perfect agreement (Cohen's Kappa = 0.832, p < 0.001). The protocol of laser application was not standardized; the laser wavelength ranged from 633 to 940 nm, with a power output range from 25 to 1600 mW. The number of sessions varied from 3 to 12, with a frequency of application from 1 time per week to 3 times per week. All studies reported pain reduction after laser therapy. Conclusions: Laser therapy is an efficient method to treat TMDs related to muscle pain. To accomplish the desired results, a standard procedure must be followed; however, the protocol is still not fully designed.

Contributions of jaw functional orthopedics in temporomandibular joint ankylosis (TMA) – clinical case report

Temporomandibular joint (TMJ) ankylosis is one of the most disabling pathological conditions that can occur in the maxillofacial region, often occurring at an early age, limiting growth and causing facial deformity, which significantly affects the quality of life of the individual. The objective of the study was to evaluate the contribution of Jaw Functional Orthopedics (JFO) in TMJ ankylosis after the surgical phase. The case of a 7-year-old female patient diagnosed with bilateral condylar ankylosis (fibrous ankylosis on the right side and bony ankylosis on the left side) is presented. On clinical examination, facial asymmetry, retrognathia, muscle contraction and opening limitation were observed. Treatment consisted of temporalis muscle flap rotation surgery with condylectomy and coronoidectomy, physical therapy, and functional therapy with OFM. The clinical results at 4 months of follow-up suggest significant progress in oral opening and protrusion. The patient showed a high degree of satisfaction with the results obtained. She is currently continuing with the use of orthopedic appliances to correct the sequelae of ankylosis and improve mandibular kinematics.

Application of Ultrasonic Bone Scalpel in Surgery for Masticatory Muscle Tendon-Aponeurosis Hyperplasia.

Masticatory muscle tendon-aponeurosis hyperplasia (MMTAH) is a disease that presents as a hard trismus due to hyperplasia of the masseter and temporalis aponeurosis. Standard surgical methods for MMTAH include masseter resection, temporalis aponeurosis, and coronoidectomy. The operation of resecting the tendon aponeurosis attached to the posterior surface of the coronoid process carries the risk of bleeding and nerve damage because it cannot be observed directly. Therefore, the authors introduce a safer method by using an ultrasonic bone scalpel for this procedure. The authors used an ultrasonic bone scalpel with a long neck blade to scrape the posterior side of the coronoid process from the bottom to the top. The authors have treated 4 cases using this technique, and in all cases, the surgical procedure was performed safely and easily. In conclusion, ultrasonic bone scalpels are effective in MMTAH surgery for removing the attachment of the stiffened temporalis muscle tendon and aponeurosis.

23-year review of spheno-orbital meningioma: clinical, radiological, and pathological insights from 100 cases

BackgroundSpheno-orbital meningioma (SOM) represents a unique variant of sphenoid wing meningiomas, distinguished by its propensity for bone infiltration and cranio-orbital involvement. SOM exhibits a considerable incidence of misdiagnosis and recurrence.PurposesTo elucidate the clinical, radiological, and pathological characteristics of SOM.MethodsReview of electronic medical records, histopathology, radiological images and follow-up information of 100 SOM patients.ResultsOf the 100 patients (28 males, 72 females) with SOM, mean age was 46.8 ± 12.6 years and prevalent symptoms were proptosis (99%). All the CT scans showed hyperostosis with 89.3% of the hyperostosis having an irregular edge. In MRI scans, dural tail sign was observed across all patients and the cranio-orbital tumors often penetrated temporal muscle (74.1%), extraocular muscle (74.1%) and lacrimal gland (63%). All the 100 patients underwent surgical intervention, and among them, 62 individuals received postoperative radiotherapy. Grade I resections had a lower recurrence rate(16.7%), which further decreased with the addition of radiotherapy(13.9%). In contrast, all patients with grade II or higher grade resections without radiotherapy experienced recurrence, indicating a higher risk associated with less complete tumor removal. The pathological examination revealed that intraorbital sections exhibited comparable tumor density to intraorbital SOM tumors, along with increased fibrous density but decreased vascular distribution.ConclusionsRadiological characteristics of SOM included cranio-orbital tumors, hyperostosis of the sphenoid wing with an irregular edge, and dural tail sign. Combination of gross total resection and adjuvant radiotherapy was recommended to minimize recurrence rate. Intracranial SOM tumors tended to be softer and more bleed-prone than intraorbital sections, necessitating surgical precision.

Three-dimensional evaluation of facial asymmetry and its association to occlusal and muscular imbalance in young women.

Diagnosing asymmetries and restoring functional balance are challenges in facial rehabilitation and aesthetic procedures. This cross-sectional observational study aimed to evaluate whether occlusal imbalance and the electromyographic activity of the masseter and temporalis muscles in young women may be associated with facial asymmetry. Fifty women (mean age ± standard deviation: 22.5 ± 2.7), without temporomandibular dysfunction and with balanced facial profiles, were divided into two groups categorized by receiver operating characteristic analysis: symmetric (n=25) and asymmetric (n=25). The variables included the evaluation of asymmetry through clinical examination, quantification of asymmetry using stereophotogrammetry through the root mean square method, asymmetry of occlusal contacts, and electromyographic activity of the masseter and temporal muscles in both latero-lateral and antero-posterior directions. The mean asymmetry indices were compared using Welch's t-test and the Mann-Whitney test. The impact of occlusal and muscular imbalance on facial asymmetry was assessed through linear regression analysis. A significant difference was observed between the groups in the asymmetry of occlusal contacts, with a considerable effect size (p<0.01 - Cohen's d=0.73). The imbalance in the electromyographic activities of the masseter and temporal muscles was considered a predictor of facial asymmetry (F=4.00, p<0.02, R²=0.15). Occlusal imbalance and electromyographic activity of the masseter and temporal muscles are associated with facial asymmetry. Key words:Facial asymmetry, masticatory muscles, stereophotogrammetry, occlusion, electromyography.

Recent Research in Singing

Abstract: This “Recent Research in Singing” article chronicles three academic documents authored during 2023 and 2024. Dissertations by Osman, Amanda, “Lost Voices: A Survey of Knowledge of Temporal Mandibular Joint Disorder and Muscle Tension Dysphonia in the Professional Voice Studio”; Sowell, Bradley Thomas, “An Analysis of Ben Moore’s Comedy Songs Using J. Peter Burkholder’s Music-Borrowing Techniques”; and You, Mengxi, “A Comprehensive Study of Alexander Tcherepnin’s Op. 71, Seven Songs on Chinese Poems With Musical Analysis and Historical Context.” Each includes a complete bibliographic citation and an Author/ProQuest abstract.

Assessment of the role of coronoid in restrictive jaw disorders and physiologic mandibular movements

Introduction: Restricted mouth opening has major health implications, such as malnutrition, difficulty in speech, and poor oral hygiene resulting in a functional shortage of the masticatory system. Reduced mouth opening can occur due to trismus, as in the oral submucous fibrosis (OSMF) condition. Excision of fibrous bands in OSMF leads to reestablishment of the mouth opening. Other than trismus, temporomandibular joint (TMJ) ankylosis is another common condition that causes fibrosis or bony ankylosis between articular surfaces. Coronoidectomy is a useful procedure that various authors nowadays apply. It is the most popular surgical procedure used as a conventional method of treatment, which includes the detachment of temporalis muscle. Materials and Methods: A group of 15 patients with OSMF and TMJ ankylosis with written informed consent were selected for the study and were operated on under general anesthesia. Preoperative and postoperative assessment was done for bite force management, measuring and comparing mandibular movements, and the electromyography (EMG) study. Results: Statistical analysis shows the increase in maximum mouth opening and lateral excursions in OSMF and TMJ ankylosis patients on the seventh, 15th, 90th days, and six months postoperatively treated either without coronoidectomy and with coronoidectomy; however, there was no significant difference was found in mean EMG and bite force readings in both groups. Conclusion: The present study concludes that the coronoidectomy not only increases the mouth opening, but masticatory efficacy is also improved with an increase in mandibular movements postoperatively in patients with OSMF and TMJ ankylosis.

Multimodal Management of Ruptured Internal Carotid Artery Blood Blister-like Aneurysm: Technical Notes and Case Series of Surgical Muscle Wrapping and Fenestration Clipping Combined with Flow-Diverter Embolization

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 2-3weeks after the clipping. All 3 patients had right ICA BBAs (mean age, 52years). 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 27.7months (15, 31, and 37months). 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.

Comparison of muscle response in patients treated with rigid and flexible fixed functional appliances.

The present study was undertaken to evaluate and compare muscle activity after the treatment with rigid and flexible fixed functional appliance. 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. 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. 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.

Temporalis muscle thickness as a predictor of functional outcome after reperfusion therapies for acute ischemic stroke: a retrospective, cohort study.

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. 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 3months represented the main endpoint of functional outcome. 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. 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.

КРИТЕРИИ ЭФФЕКТИВНОСТИ ЛЕЧЕНИЯ ПАЦИЕНТОВ С МИОФАСЦИАЛЬНЫМ БОЛЕВЫМ СИНДРОМОМ ЖЕВАТЕЛЬНОЙ МУСКУЛАТУРЫ

There are quite a lot of predictor factors for the development of myofascial pain syndrome of the chewing muscles. At the moment, there is no single pathogenetic theory of the development of this pathology. Accordingly, uniform criteria for evaluating the effectiveness of the therapy have not been developed, which was the purpose of this study. The aim of the study is to develop and implement criteria for the effectiveness of treatment of patients with myofascial masticatory muscle pain syndrome. Materials and methods. 45 people with myofascial masticatory muscle pain syndrome were examined and treated. Screening diagnostics of 30 conditionally healthy people was carried out to obtain control values. The study was conducted in three stages – assessment of stress levels according to the data of filling out a questionnaire on the level of susceptibility to stress, clinical examination – determination of qualitative and quantitative criteria, ultrasound and electromyographic examination. Relief of myofascial pain syndrome of the masticatory muscles was performed by injections of botulinum toxin type A into the masticatory and temporal muscles. The dynamics was assessed at the time of 14 days and 1 month. Results. The developed criteria clearly reflect the effectiveness of the therapy. Statistically significant results of the effectiveness of treatment have been obtained, allowing timely optimal therapy and preventing the development of chronic disorders of the temporomandibular joint. Understanding the combined influence of the psychoemotional state and somatic factors led to the development of uniform criteria for the effectiveness of treatment of this category of patients. The analysis and dynamics of changes in qualitative and quantitative indicators reflect the current trend towards the development of minimally invasive approaches to diagnosis and treatment based on the principles of biofeedback, which prevent the chronization of the process and the development of temporomandibular joint dysfunction.

Temporoparietal Fascial Flap Combined With Vascularized Outer Table Calvarial Bone Graft and Entire Temporalis Muscle: A Stable Pedicled Flap for Orbital Floor Reconstruction After Total Maxillectomy.

Orbital reconstruction after total maxillectomy is essential to maintain ocular function and facial contour. Free flap transfer with simultaneous orbital bone reconstruction is a straightforward approach; however, it is challenging in medically unstable patients with multimorbidity. The authors developed an easily harvested temporoparietal fascial flap combined with vascularized outer table calvarial bone and entire temporalis muscle. The authors applied this technique in an 81-year-old patient with multiple comorbidities who required orbital floor reconstruction following total maxillectomy. Intraoperative indocyanine green fluorescence imaging confirmed excellent perfusion of the temporoparietal fascia, entire temporalis muscle, and calvarial bone. Although the patient developed postoperative local wound infection, the vascularized bone graft resisted infection and preserved the orbital structure without bone exposure. Our technique is minimally invasive and results in a well-vascularized flap for orbital reconstruction after total maxillectomy involving the orbital bone, and particularly beneficial in patients with multimorbidity or at high risk of local infection.

Advanced Sensing System for Sleep Bruxism across Multiple Postures via EMG and Machine Learning.

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.

Effect of passive jaw opening on the electromyographic activity of the temporalis, masseter, digastric, and infrahyoid muscles in healthy adults

ABSTRACT Objective To investigate the surface electromyography (EMG) activity of the temporalis, masseter, digastric, and infrahyoid muscles during passive jaw opening in healthy adults. Methods The EMG activity of the masseter, temporalis, digastric anterior belly, and infrahyoid muscles on the right side was recorded during the four jaw-opening tasks: active opening to 20 mm (AO20); active opening to 40 mm (AO40); passive opening to 40 mm with a rubber mouth prop on the right posterior teeth (POR40); and passive opening to 40 mm with a mouth prop on the left posterior teeth (POL40). Results The EMG amplitude of the digastric anterior belly and infrahyoid muscles in either POL40 or POR40 was significantly less than that in AO20 or AO40, respectively. Conclusion Passive jaw opening reduces the EMG activity of the digastric and infrahyoid muscles significantly and could help reduce the load on these muscles during prolonged mouth-opening conditions.