The use of botulinum toxin-a in the treatment of muscular temporomandibular joint disorders

Does the Use of Botulinum Toxin in Treatment of Myofascial Pain Disorder of the Masseters and Temporalis Muscles Reduce Pain, Improve Function, or Enhance Quality of Life?

BACKGROUND

The efficacy of botulinum toxin for management of myofascial pain disorder (MPD) remains controversial.

PURPOSE

The purpose was to determine if the use of onabotulinumtoxinA (onabotA) in patients with MPD reduces pain, improves function, or enhances quality of life (QoL).

STUDY DESIGN, SETTING, AND SAMPLE

This is a multicenter, prospective, randomized, double-blinded, placebo-controlled clinical trial. Subjects with orofacial pain were screened for MPD as defined by the Diagnostic Criteria for Temporomandibular Disorders.

PREDICTOR VARIABLE

The primary predictor variable was MPD treatment with random assignment to onabotA or placebo (saline).

MAIN OUTCOME VARIABLE

The primary outcome variable was pain before treatment (T0) and at 1 month (T1) using a visual analog scale. Secondary outcome variables included pain at 2 months (T2) and 3 months (T3), maximal incisal opening (MIO), jaw function (jaw functional limitation scale), and QoL (Short Form 36) measured at T0, T1, T2, and T3.

COVARIATES

Covariates included subject demographics, prior treatments, and temporomandibular joint signs/symptoms.

ANALYSES

Descriptive and bivariate statistics included χ2 test, Fisher's exact test, or t-test.

RESULTS

Seventy five subjects with a mean age of 37 (±11) and 35 (±12) years in the onabotA and placebo groups, respectively (P = .6). Females represented 32 (86%) and 29 (76%), respectively (P = .3). Mean visual analog scale pain score in the onabotA group was 58 (±15), 39 (±24), 38 (±23), and 38 (±20) at T0, T1, T2, and T3, respectively; and the placebo group was 54 (±14), 40 (±23), 34 (±20), and 36 (±22) at T0, T1, T2, and T3, respectively. There was no statistically significant difference in pain between groups at any time point (P = .36). There was no statistically significant difference between groups in MIO (P = .124), jaw function (P = .236), or QoL domains (P > .05) at any time point. Within-group improvement in pain was seen in both groups (P < .005). Within-group improvement in jaw function was seen in the onabotA (P = .007) and placebo (P = .005) groups. There was no within-group improvement in MIO or QoL with either group (P > .05).

CONCLUSIONS

OnabotA and saline (placebo) injections both decrease pain and improve jaw function in subjects with MPD.

Comparative Efficacy of Non-Invasive Therapies in Temporomandibular Joint Dysfunction: A Systematic Review

Temporomandibular disorder (TMD) is a multifaceted disorder impacting the temporomandibular joint (TMJ), causing substantial discomfort and functional limitations. This systematic review aims to comprehensively assess the effectiveness of non-invasive treatment modalities for TMJ dysfunction, prioritizing a definitive protocol to ensure patient safety and enhance quality of life. Employing the PRISMA guidelines, we meticulously analyzed 20 studies from a pool of 1,417 articles sourced from databases such as PubMed, Google Scholar, ScienceDirect, and Medline. These studies underscore the multifarious nature of TMD and the varied responses to treatments such as physical therapy, laser therapy, ultrasound and electrical stimulation, splint therapy, injections, and arthrocentesis. Notably, the review highlights the paramount importance of precise diagnosis, often through surface electromyography, followed by a tailored treatment approach integrating manual therapy, counseling, and splint therapy. The systematic analysis revealed that while certain treatments such as transcutaneous electrical nerve stimulation and low-level laser therapy showed limited efficacy, combination therapies, especially those involving manual therapy, counseling, and splint therapy, demonstrated substantial improvement in reducing pain, depression, and anxiety. The findings advocate for a non-invasive, patient-centric approach, emphasizing education and symptom management before considering more invasive procedures such as injections and arthrocentesis. The review identifies the need for more comprehensive, longitudinal studies to establish a standardized, evidence-based treatment protocol for TMJ dysfunction, aiming to improve patient outcomes holistically.

Preliminary Findings of the Efficacy of Botulinum Toxin in Temporomandibular Disorders: Uncontrolled Pilot Study

Temporomandibular disorders are a common pathology affecting up to 70% of the population, with a maximum incidence in young patients. We used a sample of twenty patients recruited in the Maxillofacial Surgery Service of the University Hospital of Salamanca (Spain), who met the inclusion criteria, with unilateral painful symptomatology of more than three months' duration. All patients were randomly treated by intramuscular and intra-articular injections of botulinum toxin (100 U) in eight predetermined points. Pain symptomatology was assessed by the visual analog scale (VAS) at the different locations, together with joint symptomatology, at baseline and six weeks after treatment. Adverse effects were also evaluated. In 85% of the patients, pain upon oral opening improved and 90% showed improvement in pain upon mastication. A total of 75% of the patients reported improvement in joint clicking/noise. Headaches improved or disappeared in 70% of the patients treated. Despite the limitations of the study and the preliminary results, intramuscular and intra-articular infiltrations with botulinum toxin were effective in the treatment of symptoms associated with temporomandibular disorders (TMDs), with minimal adverse effects.

Patient experience and satisfaction with different temporomandibular joint treatments: A retrospective study

This retrospective study aimed to evaluate patient satisfaction with different temporomandibular joint (TMJ) treatments. Patients were included in the study according to the following inclusion criteria: 1) arthrogenous and/or myogenous temporomandibular disorders (TMD); 2) Dimitroulis classification category between 1-4; 3) conservative treatment without any improvement at least for 3 months; 4) indication for one of the following TMD treatments: injection of botulinum toxin; arthrocentesis; arthroscopy, and open surgery without alloplastic material; and 5) age ≥16 years. An independent satisfaction questionnaire with 11 queries was applied via phone call to all patients, which included 6 questions using a 10-point Likert scale and 5 yes-or-no questions. The principal outcome was the overall satisfaction with the clinical result of the treatment, and the secondary outcomes were specific satisfaction with the following: 1) pain reduction; 2) range of mouth opening; 3) chewing ability; 4) postoperative recovery; 5) the fulfillment of expectations; 6) treatment choice; 7) treatment recommendation to a friend; and 8) the need for another intervention. Anxiety and depression were also included as variables. Data were analyzed using descriptive statistics, non-parametric Kruskal-Wallis and Spearman rank correlation coefficient tests. A total of 120 patients (mean age 41.20 ± 17.78 years) were enrolled, comprising 109 women (90%) and 11 men (10%). The overall clinical satisfaction of all patients was 8.24 ± 2.23 (mean ± SD), and 97 patients (80.8%) stated that they would repeat the treatment. Patients submitted to TMJ arthrocentesis and arthroscopy had higher overall clinical satisfaction (9.09 ± 0.971 and 9.03 ± 1.13, p = 0.021) followed by open surgery (8.38 ± 1.84). The authors observed three statistically significant correlations: 1) overall clinical satisfaction and patient expectations (r = 0.803; p < 0.0001); 2) overall clinical satisfaction and post-treatment pain (r = -0.299; p = 0.003); and (3) the presence of depression and the need for further TMJ treatment (r = 0.186; p = 0.043). Within the limitations of the study it seems that patient expectations should be addressed ad initium, and the presence of a diagnosis of depression with concomitant TMD must alert the clinical team and patient for the possible need of additional treatment.

Diagnosis and Treatment of Myogenous Temporomandibular Disorders: A Clinical Update

Myogenous temporomandibular disorders (M-TMDs) are the most common chronic orofacial pain, affecting the masticatory muscles and, thus, jaw movement. While a concise diagnosis is crucial to formulate a rational treatment plan, the similarities in clinical presentations that M-TMDs share with other neuromuscular disorders affecting the temporomandibular joint (TMJ) could easily confuse physicians. In addition to the basics, such as thorough history taking and meticulous clinical examinations, different imaging techniques are useful adjuncts to facilitate the diagnostic process. This review presents an overview of the current understanding on a variety of diagnostic and treatment modalities for M-TMD patients. It is essential to highlight that there is not a single treatment for all, and the benefits of multidisciplinary strategies have been noted for the effective management of myogenous TMD pain. Treatment modalities ranging from conservative to minimally invasive options are discussed in this review.

Can Botulinum Toxin-A Contribute to Reconstructing the Physiological Homeostasis of the Masticatory Complex in Short-Faced Patients during Occlusal Therapy? A Prospective Pilot Study

The physiological homeostasis of the masticatory complex in short-faced patients is too robust to be disintegrated and reconstructed due to the powerful masseter muscle. This study innovatively introduced the botulinum toxin-A (BTX-A) into the field of dental occlusal treatment, providing a novel and minimally invasive therapy perspective for the two major clinical problems in these patients (low treatment efficiency and high rates of complications). In total, 10 adult patients with skeletal low angle seeking occlusal treatment (age: 27.0 ± 6.1 years; 4 males and 6 females) were administered 30−50 U of BTX-A in each masseter muscle and evaluated before and 3 months after injection based on cone-beam computed tomography (CBCT). We found a significant reduction in the thickness of the masseter muscle (MMT) (p < 0.0001). With regards to occlusion, we found a significant increase in the height of the maxillary second molar (U7-PP) (p < 0.05) with significantly flattened occlusal curves (the curve of Spee [COS] (p < 0.01), and the curve of Wilson [COW] (p < 0.05)). Furthermore, the variations in the temporomandibular joint exhibited a significant reduction in the anterior joint space (AJS) (p < 0.05) and superior joint space (SJS) (p < 0.05). In addition, the correlation analysis of the masticatory complex provided the basis for the following multiple regression equation: MMT = 10.08 − 0.11 COW + 2.73 AJS. The findings from our pilot study indicate that BTX-A, as a new adjuvant treatment attempt of occlusal therapy for short-faced patients, can provide a more favorable muscular environment for subsequent occlusal therapy through the adjustment of the biting force and may contribute to the reconstruction of healthier homeostasis of the masticatory complex. However, further research is required to establish the reliability and validity of these findings.

Botulinum toxin A in dentistry and orofacial surgery: an evidence-based review - part 1: therapeutic applications

Objective An evidence-based review on the safety and efficacy of botulinum toxin type-A (BoNTA) in orofacial conditions, focusing on the therapeutic applications and role of BoNTA as an adjuvant treatment.Data source and selection Data was collected using PubMed (Medline), Cochrane Library of Systematic Reviews and Cochrane Central Register of Controlled Trials electronic databases. Having satisfied the search parameters, 32 studies for therapeutic applications and 26 for BoNTA as an adjunctive treatment were included. The quality of relevant studies was assessed using the Best Evidence Topics (BETs) Critical Appraisal Tool.Data extraction The highest level of evidence (LOE) behind BoNTA safety and efficacy was for wound healing and scar management in the orofacial surgery context, where BoNTA was presented as an adjunctive modality. Level-I evidence was controversial for temporomandibular disorders and bruxism. However, it showed promising results for painful temporomandibular disorders of myogenic origin refractory to conservative therapies, and to decrease muscle contraction intensity in sleeping bruxism. There was only one level-II study for persistent recurrent aphthous stomatitis. Data showed limited level-III evidence for orofacial pain conditions (temporomandibular joint recurrent dislocation and pain, burning mouth syndrome or atypical odontalgia), oral cancer complications, or as an adjuvant to maxillofacial and orthognathic surgeries. Benefits of BoNTA in prosthodontics had weak level-IV evidence. No evidence was found among the periodontology field.Conclusion There is growing evidence to support the safety and efficacy of BoNTA in the investigated orofacial pathological conditions, with high levels of satisfaction from the patient and clinician perspective. However, there are some inconsistencies and limited high-quality evidence available. Well-designed controlled clinical trials are necessary to evaluate long-term safety, efficacy and cost-effectiveness before BoNTA is widely adopted with irrefutable evidence-based clinical guidelines.

The Effect of Zirconium Dioxide (ZrO2) Nanoparticles Addition on the Mechanical Parameters of Polymethyl Methacrylate (PMMA): A Systematic Review and Meta-Analysis of Experimental Studies

The number of studies on the subject of effects of zirconium dioxide (ZrO2) nanoparticles addition on the mechanical parameters of polymethyl methacrylate (PMMA) is still very limited. Therefore, in this research, the authors wanted to assess PMMA modified with the nano-ZrO2 additive in terms of changes in flexural, impact and tensile strength values in relation to PMMA without such component. A systematic review and meta-analysis were performed to evaluate the effect of incorporating nano-ZrO2 into PMMA on individual types of material strength. The obtained numerical data were tabulated and analyzed in the search for percentage changes in those parameters. It was then calculated for each set and the procured model was examined using residual sum of squares (RSS) to assess the discrepancy between the data and the estimation model whilst mean absolute deviation (MAD) was employed to determine robustness. The results of the systematic review were composed of data obtained from individual studies presented in eight independent articles. Overall, the addition of nano-ZrO2 increases the flexural strength of the composite with the PMMA matrix depending on the size of the ZrO2 grains administered. Unfortunately, these conclusions are based on a very limited amount of research and require further verification, especially regarding tensile strength.

Effects of ultrasound-assisted botulinum neurotoxin-A injection in patients with bruxism and masseter hypertrophy

Objectives

This study aims to explore effects of ultrasound-assisted injection of the botulinum neurotoxin-A (BoNT-A) on muscle thickness (MT) in patients with masseter hypertrophy.

Patients and methods

Between December 2018 and December 2019, a total of 20 patients (3 males, 17 females; mean age: 28±6.9 years; range, 18 to 42 years) with bruxism who underwent BoNT-A injections were reviewed retrospectively. The patients were treated using individualized injection dosages and sites. Assessment methods included length between the tragus and the angle of the mouth, maximal bite force, and MT of the masseter muscle. Follow-up data were collected from the hospital electronic database.

Results

There were 26 masseter muscles with masseter hypertrophy in 20 patients. There was a significant difference in ultrasonographic measurements of the relaxed and contracted masseter muscles between the baseline and two weeks, one month and three months after the treatment (p<0.05). In the ultrasonographic measurement of the relaxed masseter muscle, post-treatment third month values significantly differed from the second week values. The differences in the measurement of the line between the tragus and the angle of the mouth between the baseline and two weeks, one month and three months after the treatment were statistically significant (p<0.05). In the maximal bite force measurements, no significant difference was observed between the baseline and post-intervention measurements (p>0.05).

Conclusion

The MT decreases after a single dose of BoNT-A injection in patients with masseter muscle hypertrophy and ultrasonography is a convenient imaging modality for BoNT-A injection to the masseter.

Efficacy of botulinum toxin type A in the management of masticatory myofascial pain: A retrospective clinical study

BACKGROUND

Muscular pain is the main cause of disability worldwide. Myofascial pain of orofacial origin is a frequent condition, the treatment of which is not always accomplished with traditional treatment. Botulinum toxin type A (BTA) is being studied for the treatment of this type of pain with contradicting results. Thus, the objective of this study was to assess the efficacy of BTA in the therapeutic management of masticatory myofascial pain (MFP).

CASE DESCRIPTION

A retrospective study of 100 patients with a diagnosis of MFP was conducted. The control group (50 patients) received conventional treatment (prescription of a muscle relaxant and craniocervical physical therapy). The BTA group (50 patients) received this same treatment and the infiltration of 100 units of BTA in the masticatory musculature. Subjective and objective pain ratings and range of mandibular movements were recorded before and after the treatment. No differences were found between groups in the baseline values. Statistically significant improvements were found in both groups compared with baseline values in all studied parameters. Moreover, BTA improved the subjective pain ratings compared with the control group. The administration of BTA added to the conventional treatment does not seem to improve objective pain ratings and functional measurements, but it improves the subjective pain ratings.

PRACTICAL IMPLICATIONS

The addition of BTA could be beneficial in the treatment of MFP in addition to conventional treatment, but further studies are needed to elucidate the mechanisms underlying this positive effect.

Temporomandibular Disorder Patients Benefit From Intramuscular Botulinum Toxin Type a Injections

PURPOSE

The aim of this study was to analyze the clinical outcome of the use of botulinum toxin type A (BTX) intramuscular injections to the head and neck, particularly the masticatory muscles of patients with temporomandibular disorder (TMD).

METHODS

The medical records of all patients who had received intramuscular BTX injections between 2005 and 2018 at Päijät-Häme Central Hospital, Lahti, Finland were analyzed retrospectively. Gender, age, previous medical history, number of injections, injection areas, and therapeutic results were collected and analyzed. The outcome was divided into three categories based on the patients' subjective reports: not beneficial, beneficial, and highly beneficial.

RESULTS

A total of 68 patients had received intramuscular BTX injections in our unit for TMD symptoms. Clinical effectiveness could be analyzed from 63 patients. Overall, 87% of them reported favorable outcomes. 8 (13%) reported BTX injections as not beneficial, 15 (24%) as beneficial, and 40 patients (63%) as highly beneficial.Most patients had already received conventional treatment with an occlusal splint (93%) combined with pain medication (60%) in the primary care units before they were referred to our hospital.There were 59 (83%) female patients, and they responded better to BTX therapy than the male patients: 91% versus 57% (P value = 0.04). Average age at the first BTX injection visit was 44.6 years (range 17.8-77.2). Most commonly (65%), BTX was divided bilaterally to the masseter and temporalis muscles.

CONCLUSIONS

BTX injections had good therapeutic outcomes for our TMD patients. However, most patients require multiple injection visits.

Pharmacologic Treatment for Temporomandibular and Temporomandibular Joint Disorders

Temporomandibular joint disorder is defined by pain and/or loss of function of the temporomandibular joint and its associated muscles and structures. Treatments include noninvasive pharmacologic therapies, minimally invasive muscular and articular injections, and surgery. Conservative therapies include nonsteroidal anti-inflammatory drugs, muscle relaxants, benzodiazepines, antidepressants, and anticonvulsants. Minimally invasive injections include botulinum toxin, corticosteroids, platelet-rich plasma, hyaluronic acid, and prolotherapy with hypertonic glucose. With many pharmacologic treatment options and modalities available to the oral and maxillofacial surgeon, mild to moderate temporomandibular joint disorder can be managed safely and effectively to improve symptoms of pain and function of the temporomandibular joint.

Intramuscular Injections and Dry Needling within Masticatory Muscles in Management of Myofascial Pain. Systematic Review of Clinical Trials

Background: Myofascial pain is an important cause of disability among the whole population, and it is a common symptom of temporomandibular joint disorders (TMDs). Its management techniques vary widely; however, in recent years, there has been a growing interest especially in needling therapies within masticatory muscles, due to their simplicity and effectiveness in pain reduction. Methods: The construction of the following study is based on PICOS and PRISMA protocols. A systematic literature search was conducted based on the PubMed and BASE search engines. Searching the abovementioned databases yielded a total of 367 articles. The screening procedure and analysis of full texts resulted in the inclusion of 28 articles for detailed analysis. Results: According to analyzed data, clinicians manage myofascial pain either with wet or dry needling therapies. The most thoroughly studied approach that prevails significantly within the clinical trials is injecting the botulinum toxin into the masseter and temporalis. Other common methods are the application of local anesthetics or dry needling; however, we notice the introduction of entirely new substances, such as platelet-rich plasma or collagen. In the analyzed articles, the target muscles for the needling therapies are most commonly localized by manual palpation although there are a variety of navigational support systems described: EMG, MRI or EIP electrotherapy equipment, which often aid the access to located deeper lateral and medial pterygoid muscle. Conclusions: Needling therapies within masticatory muscles provide satisfactory effects while being simple, safe and accessible procedures although there still is a need for high quality clinical trials investigating especially injections of non-Botox substances and needling within lateral and medial pterygoid muscles.