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

Peripherally induced movement disorders in the stomatognathic system after oral surgical or dental procedures

OBJECTIVES

Peripherally induced movement disorders (PIMD) are hyperkinetic movement disorders that can occur after injury to a part of the body. This study aimed to identify PIMD in the stomatognathic system following dental or oral surgical procedures.

MATERIALS AND METHODS

A total of 229 patients with PIMD (144 women and 85 men; mean age: 53.4 years) triggered by oral surgical or dental interventions were evaluated retrospectively.

RESULTS

The average latency between the procedures and onset of PIMD was 14.3 days. Oral surgery (40.2%), including tooth extraction, trauma treatment, and other surgical procedures, was the most frequent trigger of PIMD. This was followed by general dental treatment, including periodontal, endodontic, and restorative procedures (36.7%), prosthetic treatment (19.7%), and orthodontic treatment (3.5%). PIMD consisted of oromandibular dystonia (73.8%), functional (psychogenic) movement disorders (11.4%), orolingual dyskinesia (7.9%), and hemimasticatory spasms (5.7%).

CONCLUSIONS

These results suggest that even minor alterations in normal anatomy or physiology after dental procedures may result in PIMD in predisposing patients.

CLINICAL RELEVANCE

Dental professionals should be aware that although infrequently, PIMD can develop after various dental treatments. If such symptoms precipitate, the attending physician should properly explain them to the patient and provide appropriate treatment or consultation with a movement disorder specialist.

Efficacy and Safety of Botulinum Toxin in the Management of Temporomandibular Symptoms Associated with Sleep Bruxism: A Systematic Review

Sleep bruxism, characterized by involuntary grinding or clenching of teeth during sleep, poses significant challenges in management due to its potential to induce temporomandibular joint disorders (TMDs) and other related symptoms. The use of Botulinum toxin Type A (BoNT-A), also known as Botox®, has been proposed as a therapeutic intervention. This systematic review aims to evaluate the efficacy and safety of BoNT-A in the management of sleep bruxism, focusing on pain reduction, improvement in jaw function, reduction in bruxism episodes, and the incidence of adverse effects. An exhaustive search was conducted across PubMed, Scopus, and Embase databases up to January 2024, adhering to the PRISMA guidelines. Nine randomized clinical trials (RCTs) involving 137 participants were analyzed for efficacy and safety outcomes. The studies demonstrated a significant reduction in mean pain scores (from 7.1 to 0.2 at 6 months and 1 year post-treatment in one study) and a notable decrease in the number of bruxism events (from 4.97/h to 1.70/h in the BoNT-A group in another study). Additionally, improvements were observed in jaw stiffness and total sleep time. Adverse effects varied but were generally mild and transient, including injection site pain in 20% of participants in one study and cosmetic changes in smile in 15.4% of patients in another. These findings suggest that BoNT-A injections may provide some benefits for treating nocturnal bruxism, potentially reducing TMD symptoms like pain and improving jaw function. However, these findings are preliminary due to variability in study designs and the absence of detailed statistical analysis.

Therapeutic Uses and Efficacy of Botulinum Toxin in Orofacial Medicine: A Dental Perspective

Botulinum neurotoxin (BoNT) is the exotoxin of Clostridium botulinum, a Gram-positive, spore-forming bacterium [...].

Aesthetic Rehabilitation Medicine: Enhancing Wellbeing beyond Functional Recovery

Although rehabilitation medicine emphasizes a holistic health approach, there is still a large gap of knowledge about potential interventions aimed at improving overall wellbeing through cosmetic interventions. Therefore, this narrative review investigates the role of different rehabilitative techniques in enhancing aesthetics, quality of life, and psychosocial wellbeing for patients with disabilities. The study follows the SANRA framework quality criteria for a narrative review. Literature searches across PubMed/Medline, Web of Science, and Scopus identified articles focusing on rehabilitation strategies within the aesthetic rehabilitation domain. The review identified evidence supporting injection procedures, such as Botulinum Toxin, Platelet-Rich Plasma, Hyaluronic Acid, Ozone, and Carboxytherapy, and assessing their applications in several disabling disorders. Additionally, physical therapies like Extracorporeal Shock Wave Therapy, Laser Therapy, Microcurrent Therapy, Tecar Therapy, and physical exercises were explored for their impact on cutaneous microcirculation, cellulite treatment, wound healing, and scar appearance improvement. Lastly, the manuscript underlines the role of manual therapy techniques in addressing both physical discomfort and aesthetic concerns, discussing their effectiveness in adipose tissue therapy, scar tissue mobilization, and regional fat thickness reduction. Taken together, this review emphasizes the role of a multidisciplinary approach, aiming to provide valuable insights into potential benefits for both functional and aesthetic outcomes.

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.

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.

Task-specific oromandibular dystonia secondary to chewing Khat (Catha edulis)- A series of 35 cases

BACKGROUND

The leaves of "Khat" (Catha edulis), an indigenous shrub of Yemen and Arabian Peninsula are habitually chewed by the inhabitants for psychostimulant properties.

OBJECTIVE

To describe a unique task specific Oro-mandibular dystonia (OMD) in Yemenese men, with a temporal association with chewing "Khat".

METHODS

Multicentric, retrospective analysis (2009-2020) of patients with OMD associated with "Khat" chewing, evaluating clinical features and response to Onabotulinum toxin A.

RESULTS

35 Yemenese men with a negative family history, normal neuroimaging mean age of 44.31(±3.21) years and prolonged (20.31 ± 3.27 years) history of chewing Khat, around 5.16(±0.80) hours/day presented with OMD-20 jaw opening, 13 jaw closing and 2 mixed affecting chewing (n = 6), speech (n = 3), or both (n = 26). Additional lingual dystonia was seen in five.

CONCLUSIONS

Chewing of khat is a repetitive task involving the jaw musculature and may be one of the causative factors of this task specific OMD. Recognition can prevent disability in these regions.

It Is Time for a Multidisciplinary Rehabilitation Approach: A Scoping Review on Stomatognathic Diseases in Neurological Disorders

Patients affected by neurological disorders can develop stomatognathic diseases (SD) related to decreased bite force and quality of mastication, bruxism, severe clicking and other temporomandibular disorders (TMD), which deeply affect patients' swallowing, masticatory and phonation functions and, therefore, their quality of life. The diagnosis is commonly based on medical history and physical examination, paying attention to the temporomandibular joint (TMJ) range of movements, jaw sounds and mandibular lateral deviation. Diagnostic tools such as computed tomography and magnetic resonance imaging are used instead in case of equivocal findings in the anamnesis and physical evaluation. However, stomatognathic and temporomandibular functional training has not been commonly adopted in hospital settings as part of formal neurorehabilitation. This review is aimed at describing the most frequent pathophysiological patterns of SD and TMD in patients affected by neurological disorders and their rehabilitative approach, giving some clinical suggestions about their conservative treatment. We have searched and reviewed evidence published in PubMed, Google Scholar, Scopus and Cochrane Library between 2010 and 2023. After a thorough screening, we have selected ten studies referring to pathophysiological patterns of SD/TMD and the conservative rehabilitative approach in neurological disorders. Given this, the current literature is still poor and unclear about the administration of these kinds of complementary and rehabilitative approaches in neurological patients suffering from SD and/or TMD.

Botulinum Toxin and Percutaneous Needle Electrolysis for the Treatment of Chronic Masticatory Myalgia

Botulinum toxin type A (BTA) is applied in muscle hyperactivity disorders and injected into affected muscles, producing deep and persistent muscle relaxation. Several multidisciplinary groups investigated the treatment of temporomandibular disorders for several years, and there is currently some data on the beneficial effects of BTA in specific cases of chronic masticatory myalgia. Percutaneous needle electrolysis (PNE), which applies a low-intensity galvanic current to promote tissue regeneration, has been shown to be effective in reducing pain and improving masticatory function. The purpose of this study was to investigate the efficacy and safety of BTA and to assess whether its application in patients with localized masticatory myalgia can significantly reduce pain and improve function compared to a group treated with PNE. Fifty-two patients with long-term refractory masticatory myalgia were randomly assigned to two groups. The BTA group (n = 26) received a bilateral botulinum toxin injection and the PNE group (n = 26) received percutaneous electrolysis. The dose of BTA injected was 100 units distributed among the main primary masticatory muscles, and PNE was administered at 0.5 mA/3 s/3 consecutive times in a single session. Patient assessments were performed prior to treatment and one, two, and three months after treatment. The results revealed good therapeutic response in both groups. In the long term, both BTA and PNE showed high efficacy and safety in reducing pain and improving muscle function for the treatment of chronic masticatory myalgia. This improvement was sustained over a three-month period in both groups. Therefore, the use of BTA and PNE could be considered a valid and safe therapeutic alternative among the available options to treat refractory and localized masticatory myalgia when a better therapeutic response is expected as it demonstrated high efficacy.

Botulinum toxin for motor disorders

Botulinum neurotoxins are a group of biological toxins produced by the gram-negative bacteria Clostridium botulinum. After intramuscular injection, they produce dose-related muscle relaxation, which has proven useful in the treatment of a large number of motor and movement disorders. In this chapter, we discuss the utility of botulinum toxin treatment in three major and common medical conditions related to the dysfunction of the motor system, namely dystonia, tremor, and spasticity. A summary of the existing literature is provided along with different techniques of injection including those recommended by the authors.

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.

Tardive Oromandibular Dystonia Induced by Trazodone: A Clinical Case and Management from the Perspective of the Dental Specialist

BACKGROUND

Tardive Oromandibular Dystonia is an iatrogenic drug-induced movement form of extrapyramidal symptoms associated primarily with chronic consumption of dopamine receptor blocking agents. Tardive symptoms attributable to selective serotonin reuptake inhibitors antidepressants are far less prevalent.

CLINICAL CASE

The authors will present a clinical case and management, from the dental specialist perspective, of a 55-year-old female patient who developed tardive oromandibular dystonia induced by Trazodone prescribed for sleep insomnia.

CONCLUSIONS

Trazodone-induced oromandibular dystonia is extremely rare. Early identification and assessment of tardive symptoms are imperative for successful treatment. Trazodone should be prescribed with caution in patients taking other medications with the potential to cause tardive syndromes.

Botulinum Toxin, a Drug with Potential Interest for Dentists—An Introduction

The review is an introduction to medical, non-cosmetic treatments with botulinum neurotoxin (BoNT) in the orofacial region. It focuses on the current most common, best-documented and safest indications of interest for dentists in terms of dystonia and sialorrhea. These conditions are recommended to start with and suitable to gain better skill and experience with BoNT. The introduction also stresses the importance of correct diagnostics based on interdisciplinary cooperation, precise targeting of the injections, measurements of treatment effect, and control of the oral health with regard to side effects.

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.

Patient selection and injection techniques for botulinum neurotoxin in oromandibular dystonia

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Botulinum toxin is considered as the first-line therapy in oromandibular dystonia (OMD) by most experts and evidence-based literature.

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Oromandibular dystonia (OMD) can be classified into several subtypes so primary muscle involvements can be identified for botulinum toxin (BoNT) injections.

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This review article aims to provide a framework for practical clinical approaches in patients with OMD for BoNT injections.

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Careful stepwise planning is recommended to identify primary muscles responsible and employ a conservative approach to dosing titration.

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Treating physicians should be diligent to observe for adverse events as muscles involved in OMD are small, delicate and situated in close proximity.

Oromandibular dystonia (OMD) is a form of focal dystonia that involves the masticatory, lower facial, labial, and lingual musculature. It is a disabling disorder which had limited treatment options until the recent introduction of botulinum toxin (BoNT) as the recommended first-line therapy by most experts and evidence-based literature. Owing to the complex relationship between the muscles of mastication and surrounding muscles, there is a wide variety of dynamic clinical presentations, making clinical recognition and the corresponding approach to BoNT injection therapy difficult. In this review, the authors provide a framework for practical clinical approaches, beginning with the recognition of clinical subtypes of OMD (jaw-opening, jaw-closing, jaw-deviating, lingual, peri-oral, and/or pharyngeal dystonias), followed by patient selection and clinical evaluation to determine function interferences, with injection techniques illustrated for each subtype. Careful stepwise planning is recommended to identify the muscles that are primarily responsible and employ a conservative approach to dosing titration. Treating physicians should be diligent in checking for adverse events, especially for the first few injection cycles, as muscles involved in OMD are small, delicate, and situated in close proximity. It is recommended that future studies should aim to establish the clinical efficacy of each subtype, incorporating muscle targeting techniques and patient-centred outcome measures that are related to disturbed daily functions.