Hemimasticatory spasm: a series of 17 cases and a comprehensive review of the literature.

Hemimasticatory spasm (HMS) is a rare movement disorder characterized by paroxysmal spasms or twitches of the unilateral jaw-closing muscles. This study aimed to comprehensively evaluate the clinical features of patients with HMS. Data from 17 patients newly diagnosed with HMS (12 females and 5 males; mean age at onset: 46.7 years) who visited our department were retrospectively analyzed, and a literature search based on electronic medical databases from their inception until November 30, 2023, was conducted. A manual search was conducted for articles cited in the related literature. A total of 117 cases (72 females and 45 males; mean age at onset: 37.1 years) from 57 studies were analyzed. The muscles involved were the masseter (97.4%), temporalis (47.9%), and medial pterygoid (6%). Morphea or scleroderma was observed in 23.9% of the patients, and facial hemiatrophy in 27.4%. In 17.9% of the cases, Parry-Romberg syndrome was either complicated or suspected. Typical electromyographic findings included the absence of a silent period during spasms (23.9%) and irregular brief bursts of multiple motor unit potentials. Oral medicines, such as clonazepam or carbamazepine, alleviated the symptoms for some patients but were often unsatisfactory. Botulinum toxin therapy was effective in most cases. Recently, microvascular decompression surgery is increasingly being used, resulting in complete relief in some cases. In conclusion, highly effective modalities are currently available, and it is necessary to raise awareness of HMS to ensure that it can be diagnosed and treated accurately by both medical and dental professionals.

Japanese Wooden Plate Denture as Origin of Suction Retention.

The modern theory of complete denture retention using suction was applied to wooden plate dentures in Japan from the first half of the 16th century, which is an astonishing achievement since it was clinically applied in North America and Europe in the latter half of the 19th century nearly 300 years later. Wooden dentures are unique to Japan resulting from skilled Japanese craftsmanship and are not found in other countries. We comprehensively reviewed reports on wooden plate dentures, analyzed 145 complete and partial dentures, and discussed their history. Japanese wooden plate dentures are mainly made of box wood, and artificial teeth are made of pagodite, ivory, and natural teeth. Small nails were driven into the molar region. Many existing dentures revealed attrition on the occlusal faces, thereby indicating that the wearers were able to masticate sufficiently. Wooden plate dentures have been used for 400 years in the early 20th century. Although Japanese wooden dentures have not been mentioned in the history of dentistry in Western literature, they comprise an important part of the history of denture development.

Guillain-Barré Syndrome Presenting With Masticatory Disturbance and Reduction in Bite Force.

Guillain-Barré syndrome is a rare, rapidly progressive, and potentially fatal immune-mediated neuropathy. A 17-year-old male patient with a fever of 38°C developed masticatory impairment a few days later. Although the fever resolved after one week, the restricted mouth opening and decreased bite force persisted. Thirty-five days after disease onset, the patient was referred to our clinic and reported severe masticatory dysfunction due to a significant reduction in maximum bite force (left: 0 N, right: 12.7 N). His maximal mouth opening was 24 mm without jaw deviation. An electrophysiological study revealed Guillain-Barré syndrome (acute motor axonal neuropathy). The patient was closely monitored as he underwent rehabilitation comprising mouth opening and mastication training. The patient's bite force and masticatory impairment due to the weakness of the muscles of mastication gradually improved. At one year and five months after disease onset, the masticatory impairment had fully resolved. His maximum bite force two years after disease onset was 158.3 N on the left side and 172.2 N on the right side.

[A Recurrent Colon Cancer Successfully Treated by Nivolumab plus Ipilimumab with On and Off for Preventing Exacerbation of Skin Disorders].

Here, we report a case in which nivolumab plus ipilimumab combination therapy was significantly effective for MSI-high recurrent colon cancer with acute exacerbation after 5-FU/L-OHP/CPT-11 treatment. At the end of 4 cycles of combination therapy, clinical CR was obtained on diagnostic imaging. At the end of the 2 cycles of transition from combination therapy to monotherapy, eosinophilia was observed in a quadratic function, and exacerbation of skin disorders was observed. Eosinophil counts normalized promptly after discontinuation of treatment, and skin disorders gradually improved. Two months after the discontinuation of treatment, monotherapy was restarted. After the resumption of treatment, an increase in eosinophils and worsening of skin symptoms were observed again, and stopped treatment. We report an interesting case in which immune checkpoint inhibiter were turned on and off according to eosinophil counts for preventing exacerbation of skin disorders, and for maintaining cancer remission by continuing immune checkpoint inhibitor treatment.

Superior Dislocation of the Mandibular Condyle into the Middle Cranial Fossa: A Comprehensive Review of the Literature.

The superior dislocation of the condyle into the cranium occasionally requires invasive procedures due to the absence of a timely diagnosis. This review analyzed the available clinical data to provide information on treatment decisions. The reports were assessed using electronic medical databases from inception to 31 October 2022. A total of 116 cases from 104 studies were assessed; among the patients, 60% and 87.5% of the affected women and men required open reduction, respectively. The ratio of closed to open procedures within 7 days after injury was maintained; however, closed reduction decreased over time, and all cases required open reduction after 22 days. Eighty percent of the patients with a total intrusion of the condyle required open reduction, whereas the frequency for both procedures was comparable in the remaining patients. Open reduction was significantly more frequently performed for men (p = 0.026, odds ratio; 4.959, 95% confidence interval; 1.208-20.365) and less frequently performed in cases with partial intrusion (p = 0.011; odds ratio: 0.186; 95% confidence interval: 0.051-0.684); the frequency varied according to the time until treatment (p = 0.027, odds ratio; 1.124, 95% confidence interval; 1.013-1.246). Appropriate diagnostic imaging and prompt diagnosis are indispensable for minimally invasive treatment of this condition.

Task-Specific Lingual Dystonia During Japanese Religious Services.

INTRODUCTION: Lingual dystonia is a subtype of oromandibular dystonia characterized by involuntary contractions of the tongue muscles, often provoked by speaking or eating. METHODS: This study reports six Japanese cases (four female and two male, mean age at onset of 49.5 years) with task-specific lingual dystonia during praying. In the early phase, all patients experienced lingual protrusion exclusively during Japanese religious services. When the patients start speaking, the tongues protrude forward, making it difficult to pronounce words. The patients were treated with multimodal treatment, including muscle afferent block (MAB) therapy comprising local anesthetic injection, botulinum toxin (onabotulinumtoxinA) injection, and a sensory trick splint. RESULTS: MAB therapy was conducted in five patients (mean time: 5.8), and botulinum toxin injection was administered in four patients (mean time: 8). The injected muscles were the genioglossal muscles and, in one case, the lateral pterygoid muscle. Sensory trick splints were inserted in three patients. After the multimodal therapy, the patients were able to pronounce words smoothly and clearly. Oromandibular Dystonia Rating Scale scores improved significantly (P<0.005) from baseline (187 points) to endpoint (47 points) with a mean follow-up of 4.7 years. CONCLUSION: Although this entity is rare, medical and dental professionals should be aware of this peculiar symptom. Multimodal therapy is required to ensure effective treatment of praying-induced lingual dystonia.

Neurophysiological Basis of Deep Brain Stimulation and Botulinum Neurotoxin Injection for Treating Oromandibular Dystonia.

Oromandibular dystonia (OMD) induces severe motor impairments, such as masticatory disturbances, dysphagia, and dysarthria, resulting in a serious decline in quality of life. Non-invasive brain-imaging techniques such as electroencephalography (EEG) and magnetoencephalography (MEG) are powerful approaches that can elucidate human cortical activity with high temporal resolution. Previous studies with EEG and MEG have revealed that movements in the stomatognathic system are regulated by the bilateral central cortex. Recently, in addition to the standard therapy of botulinum neurotoxin (BoNT) injection into the affected muscles, bilateral deep brain stimulation (DBS) has been applied for the treatment of OMD. However, some patients' OMD symptoms do not improve sufficiently after DBS, and they require additional BoNT therapy. In this review, we provide an overview of the unique central spatiotemporal processing mechanisms in these regions in the bilateral cortex using EEG and MEG, as they relate to the sensorimotor functions of the stomatognathic system. Increased knowledge regarding the neurophysiological underpinnings of the stomatognathic system will improve our understanding of OMD and other movement disorders, as well as aid the development of potential novel approaches such as combination treatment with BoNT injection and DBS or non-invasive cortical current stimulation therapies.

Effects of Botulinum Toxin Therapy on Health-Related Quality of Life Evaluated by the Oromandibular Dystonia Rating Scale.

Oromandibular dystonia (OMD) refers to a focal dystonia in the stomatognathic system. Health-related quality of life (HRQoL) in isolated dystonia is associated with non-motor symptoms such as depression, anxiety, and pain, as well as motor symptoms. To evaluate HRQoL in patients with OMD, the therapeutic effects of botulinum neurotoxin (BoNT) therapy were assessed using a recently developed and validated comprehensive measurement tool called the Oromandibular Dystonia Rating Scale (OMDRS). Altogether, 408 patients (jaw closing dystonia, n = 223; tongue (lingual) dystonia, n = 86; jaw opening dystonia, n = 50; jaw deviation dystonia, n = 23; jaw protrusion dystonia, n = 13; and lip (labial) dystonia, n = 13) were evaluated at baseline and after the end of BoNT therapy or in a stable status. The total OMDRS score reduced significantly from 149.1 to 57.6 (p < 0.001). Mean improvement was 63.1%. All examiner-rated subscales (severity, disability, and pain) and patient-rated questionnaire scores (general, eating, speech, cosmetic, social/family life, sleep, annoyance, mood, and psychosocial function) were significantly lower at the endpoint than at baseline (p < 0.001). The BoNT injection had a highly positive impact on patient HRQoL, and the OMDRS could evaluate both motor phenomena and non-motor symptoms.

Pneumoparotid related to obstructive sleep apnea syndrome treated by oral appliance with anterior opening to reduce intraoral pressure.

Pneumoparotid is associated with retrograde air insufflation in Stensen's duct and the parotid gland. A 57-year-old man experienced swelling and pain in the right parotid region after sleeping during a flight. Pneumoparotid and obstructive sleep apnea syndrome were diagnosed. Pneumoparotid was suspected as caused by increased intraoral pressure during sleep; thus, an oral appliance to reduce intraoral pressure was effective. After 9 years, the symptoms recurred on the left side. The appliance was reinserted and helped substantially. This is the first case report of obstructive sleep apnea syndrome accompanying pneumoparotid, treated effectively with an oral appliance, with a 10-year follow-up.

Botulinum Toxin Therapy for Oromandibular Dystonia and Other Movement Disorders in the Stomatognathic System.

Various movement disorders, such as oromandibular dystonia, oral dyskinesia, bruxism, functional (psychogenic) movement disorder, and tremors, exist in the stomatognathic system. Most patients experiencing involuntary movements due to these disorders visit dentists or oral surgeons, who may be the first healthcare providers. However, differential diagnoses require neurological and dental knowledge. This study aimed to review scientific advances in botulinum toxin therapy for these conditions. The results indicated that botulinum toxin injection is effective and safe, with few side effects in most cases when properly administered by an experienced clinician. The diagnosis and treatment of movement disorders in the stomatognathic system require both neurological and dental or oral surgical knowledge and skills, and well-designed multicenter trials with a multidisciplinary team approach must be necessary to ensure accurate diagnosis and proper treatment.

Etiology of Pneumoparotid: A Systematic Review.

Pneumoparotid describes retrogradely insufflated air within the Stensen's duct and/or parotid gland. It is a rare condition with variable causative factors. This study aimed to elucidate the clinical characteristics of pneumoparotid. Reports in all languages were evaluated following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement 2020. A literature search was conducted using electronic medical databases (PubMed, Scopus, Web of Science, EBSCO, Ovid, Google Scholar, SciElo, LILIACS, and others) from 1890 to 30 June 2022. One hundred and seventy patients (mean age; 28.4 years) from 126 studies were reviewed. Common symptoms included swelling (84.7%) and pain (35.9%). Characteristic findings were crepitus in the parotid region (40%) and frothy saliva from the orifice (39.4%). The common etiologies included abnormal habits such as blowing out the cheeks (23.5%), idiopathic (20%), self-induced (15.9%), playing wind instruments such as trumpets or flutes (8.8%), and diseases inducing coughing or sneezing (8.2%). The treatments included antibiotic therapy (30%), behavioral therapy to avoid continuing causative habits (25.9%), psychiatric therapy (8.2%), and surgical procedures (8.2%). Treatment should be individualized and etiology-based. However, the etiology was not identified in 20% of patients. Further detailed data from larger samples are required to clarify and improve the recognition of this entity.

Population genetic structure of raccoons as a consequence of multiple introductions and range expansion in the Boso Peninsula, Japan.

The raccoon (Procyon lotor) is an invasive carnivore that invaded various areas of the world. Although controlling feral raccoon populations is important to reduce serious threats to local ecosystems, raccoons are not under rigid population control in Europe and Japan. We examined the D-loop and nuclear microsatellite regions to identify spatially explicit and feasible management units for effective population control and further range expansion retardation. Through the identification of five mitochondrial DNA haplotypes and three nuclear genetic groups, we identified at least three independent introductions, range expansion, and subsequent genetic admixture in the Boso Peninsula. The management unit considered that two were appropriate because two populations have already genetic exchange. Furthermore, when taking management, we think that it is important to monitor DNA at the same time as capture measures for feasible management. This makes it possible to determine whether there is a invasion that has a significant impact on population growth from out of the unit, and enables adaptive management.

Effects of Botulinum Toxin Type A on Pain among Trigeminal Neuralgia, Myofascial Temporomandibular Disorders, and Oromandibular Dystonia.

The differences in analgesic effects of botulinum toxin type A were compared in 28 patients with trigeminal neuralgia, 53 patients with myofascial temporomandibular disorders, and 89 patients with the jaw closing oromandibular dystonia. The patients were treated by injection of botulinum toxin type A into the masseter, temporalis, medial pterygoid, and other muscles based on the symptoms of each patient. The pain severity was evaluated using the visual analog scale, pain frequency, and pain scale of the oromandibular dystonia rating scale. Botulinum toxin injection was performed 1068 times in all patients without significant adverse effects. The visual analog, pain frequency, and pain scales at baseline were reduced (p < 0.001) after two, four, eight, and 12 weeks after the first botulinum toxin therapy and at the endpoint. The effects differed significantly (p < 0.001) among the groups (repeated-measures analysis of variance). The mean improvement (0%, no effect; 100%, complete recovery) at the endpoint was 86.8% for trigeminal neuralgia, 80.8% for myofascial pain, and 75.4% for oromandibular dystonia. Injection of the botulinum toxin can be a highly effective and safe method to treat trigeminal neuralgia, myofascial pain, and oromandibular dystonia.

Should spring water cysts of the mediastinum require excisional resection? A case report.

INTRODUCTION AND IMPORTANCE: Mediastinal cysts account for 20-32% of all mediastinal lesions. Complete surgical excision is the standard therapy for mediastinal cysts. Translucent cysts containing crystal-clear fluid are called "spring water cysts." We experienced a case of mediastinal spring water cyst fenestrated under video-assisted thoracoscopy with a miniaturized endoscope (mini-VATS) as an alternative to excisional resection. CASE PRESENTATION: A 49-year-old woman presented with back pain. Chest CT revealed a posterior mediastinal mass measuring 4.2 × 1.8 × 3.2 cm closed to the tenth thoracic vertebra. Chest MRI demonstrated hypo-intensity on T1-weighted images and hyper-intensity on T2-weighted images. It was estimated that the posterior mediastinal mass did not contain a tumor component. The tumor was growing and symptomatic; therefore, we performed surgical cyst fenestration without excision of the cyst under mini-VATS. The patient experienced complete relief of symptoms. Fluid accumulation in the cyst was not observed on CT images 12 months postoperatively. CLINICAL DISCUSSION: Kozu et al. reported that all 108 primary mediastinal cysts were resected completely and were recurrence-free after a mean follow-up of 41 ± 26 months. In the case of a functional hydrocele such as spring water cyst, we believe that even if fluid is produced, the thoracic pleura is capable of absorbing the fluid, and the cyst wall might not recur even if the wall is left in place. Fluid drainage through fenestration may prevent recurrent fluid collection. CONCLUSION: Fenestration of non-neoplastic mediastinal cysts under mini-VATS might be a less invasive radical procedure compared to complete resection.

Prevalence and incidence of oromandibular dystonia: an oral and maxillofacial surgery service-based study.

OBJECTIVES: Oromandibular dystonia is a focal dystonia characterized by sustained or intermittent contractions of the masticatory and/or tongue muscles. This epidemiological study aimed to estimate the prevalence and incidence of oromandibular dystonia in Kyoto (population: 1,465,701). MATERIALS AND METHODS: The population sample was citizens of Kyoto who visited our department between 2015 and 2019 and were differentially diagnosed by an oromandibular dystonia specialist having idiopathic (primary) and acquired (secondary) oromandibular dystonia. A total of 144 patients (100 women and 44 men; mean age, 57.5 years) were analyzed for clinical features, and the prevalence (prevalence date, January 1, 2020) and annual incidence were estimated. RESULTS: The male-to-female ratio was 1:2.3 (p<0.001). Age at onset was significantly (p<0.01) earlier in men (47.5 years) than that in women (56.9 years). The crude prevalence of oromandibular dystonia was estimated at 9.8 per 100,000 persons (95% confidence interval: 8.3-11.6) (idiopathic dystonia, 5.7 [4.6-7.1]; tardive dystonia, 3.4 [2.5-4.5]) and incidence at 2.0 (1.3-2.8) per 100,000 person-years (idiopathic dystonia, 1.2 [0.68-1.9], tardive dystonia, 0.68 [0.32-1.3]). The prevalence was 13.0 (10.5-15.8) in women and 6.3 (4.6-8.5) in men. All age groups showed female predominance. The highest prevalence was 23.6 (14.4-36.5) in women aged 60-69 years. CONCLUSIONS: As this is an oral and maxillofacial surgery service-based study, the actual prevalence of oromandibular dystonia may be even higher. CLINICAL RELEVANCE: It was suggested that oromandibular dystonia might be more common than cervical dystonia or blepharospasm.

[Therapeutic strategies for oromandibular dystonia]. / Behandlungsstrategien bei oromandibulärer Dystonie.

Oromandibular dystonia is characterized by tonic or clonic involuntary spasms of the masticatory, lingual and / or muscles in the stomatognathic system. It is often misdiagnosed as craniomandibular dysfunction or psychiatric disease. According to clinical features, the oromandibular dystonia is classified into 6 subtypes (jaw closing-, jaw opening-, tongue-, jaw deviation-, jaw protrusion-, and lip dystonia). There are several treatment methods like botulinum toxin injection, muscle afferent block (injection of lidocaine and alcohol into the masticatory or tongue muscles for blocking muscle afferents from muscle spindle), occlusal splint, and oral surgery (coronoidotomy). Most of patients can be treated successfully according to subtype by combination of these treatments. Special treatment recommendations for each subtype were described in this focus article. Accurate diagnosis and treatment of oral dystonia requires comprehensive knowledge and skills of both oral and maxillofacial surgery and neurology. Therefore, collaboration among these departments is very important.

Development of the binary vector pTACAtg1 for stable gene expression in plant: Reduction of gene silencing in transgenic plants carrying the target gene with long flanking sequences.

Genetic modification in plants helps us to understand molecular mechanisms underlying on plant fitness and to improve profitable crops. However, in transgenic plants, the value of gene expression often varies among plant populations of distinct lines and among generations of identical individuals. This variation is caused by several reasons, such as differences in the chromosome position, repeated sequences, and copy number of the inserted transgene. Developing a state-of-art technology to avoid the variation of gene expression levels including gene silencing has been awaited. Here, we developed a novel binary plasmid (pTACAtg1) that is based on a transformation-competent artificial chromosome (TAC) vector, harboring long genomic DNA fragments on both sides of the cloning sites. As a case study, we cloned the cauliflower mosaic virus 35S promoter:ß-glucuronidase (35S:GUS) gene cassettes into the pTACAtg1, and introduced it with long flanking sequences on the pTACAtg1 into the plants. In isolated transgenic plants, the copy number was reduced and the GUS expressions were detected more stably than those in the control plants carrying the insert without flanking regions. In our result, the reduced copy number of a transgene suppressed variation and silencing of its gene expression. The pTACAtg1 vector will be suitable for the production of stable transformants and for expression analyses of a transgene.