The therapeutic use of botulinum toxin in cervical and maxillofacial conditions: an evidence-based review

Botox: Current and Emerging Trends for Dental Practitioners in Esthetic Dentistry

There are numerous medical and dental disorders for which there are no effective traditional therapy options. For various medical and dental disorders, botulinum toxin (BT) can be employed as an alternate therapeutic option that uses the chemodenervation approach. The range of dentistry treatment choices is expanding quickly. Applications of non-traditional therapy alternatives, such as the use of BT, are becoming more and more common in this situation. Although BT has been shown to be effective in a number of circumstances, its application in esthetic operations, such as the treatment of facial wrinkles, has gained widespread acceptance. This research is especially interested in applications of BT related to dentistry in the craniofacial region. For many diseases that a dentist would be interested in treating, BT provides a temporary, reversible, and generally safe therapy option. Due to their extensive knowledge of the anatomy of the faciomaxillary region, dental surgeons are a potential pool of operators who, with a small amount of skill enhancement, can use BT in their toolkit. This broadens the scope of minimally invasive alternatives to invasive protocols or refractory conditions. An online search was conducted for the use of BT in dentistry; all studies and articles pertaining to the subject were chosen, and dental-related content was removed and summarized. The fundamentals of BT and some of its applications in dentistry are covered in this article. The comprehensive details of its application in dentistry will be covered in the upcoming sections.

Botulinum Toxin-A for the Treatment of Myogenous Temporomandibular Disorders: An Umbrella Review of Systematic Reviews

OBJECTIVE

Temporomandibular disorders (TMDs) encompass several conditions that cause pain and impair function of the masticatory muscles (M-TMDs) and temporomandibular joints. There is a large interest among clinicians and researchers in the use of botulinum toxin-A (BoNT-A) as a treatment for M-TMD. However, due to the lack of consistent evidence regarding the efficacy as well as adverse events of BoNT-A, clinical decision making is challenging. Therefore, this umbrella review aimed to systematically assess systematic reviews (SRs) evaluating BoNT-A treatment effects on pain intensity, mandibular movements, and adverse events in patients with M-TMDs.

METHOD

An electronic search was undertaken in the databases MEDLINE, EMBASE, CINAHL, Cochrane Central Registry of Controlled Trials (CENTRAL), Web of Science, Epistemonikos, ClinicalTrials.gov, and ICTRP to identify SRs investigating BoNT-A effects on M-TMDs, published from the inception of each database until 6 December 2023. The quality of evidence was rated according to the critical appraisal checklist developed by the umbrella review methodology working group. Only high-quality SRs were included.

RESULTS

In total, 18 SRs were included. BoNT-A was shown to be more effective than placebo to reduce pain intensity, but not compared to standard treatments. Additionally, BoNT-A was not superior to placebo or standard treatments regarding improvement of mandibular movements. BoNT-A was considered to have a higher risk for adverse events on muscle and bony tissue compared with other treatments.

CONCLUSION

The synthesis in this umbrella review provides the highest level of evidence present. Taken together, there are indications of effectiveness of BoNT-A for treatment of M-TMDs, supported by moderate evidence. However, considering the risk of causing serious adverse events, treatment with BoNT-A is recommended to be the last treatment alternative.

Effects of different interventions on bruxism: an overview of systematic reviews

OBJECTIVE

This study aimed to evaluate, qualify, and summarize evidence presented in systematic reviews (SR) on treatments for bruxism.

METHODS

The overview was conducted using the PICO strategy: children, adolescents, and adults with bruxism (P) were submitted to different treatments (I) compared to other treatments, placebo, or no treatment (C) in order to evaluate incidence, prevalence, and number of episodes of bruxism (O). The search was carried out in six databases and gray literature up to July 2023. Data were extracted, and the ROBS tool was used, followed by a descriptive synthesis of the results.

RESULTS

A total of 31 SR were included. Sixteen showed a positive effect on episodes of bruxism (BE), while two had negative, one had neutral, and nine had inconclusive effects. Using the risk of bias in systematic reviews tool (ROBIS), risk of bias varied from low (n = 23) to high (n = 5) among the SR. Pharmacological treatment, oral rehabilitation, and other therapeutic approaches presented inconclusive or negative effects on BE, while oral appliances showed controversial effects. Biofeedback, physical therapy, laser therapy, and botulinum toxin showed positive effects on the reduction of BE.

CONCLUSION

Biofeedback, physical therapy, laser therapy, and botulinum toxin showed positive effects on the reduction of BE; there is still a lack of studies to support the safe and long-term use of these therapies.

REGISTRATION NUMBER

PROSPERO CRD42021273905.

Botulinum Toxin Injection into the Digastric Muscle: Current Clinical Use and a Report of Five Cases

The present research aimed to review the clinical applications of botulinum toxin-A (BTX-A) injection into the anterior belly of the digastric muscle (ABDM) and to highlight the potential role of the BTX-A injection into ABDM in preventing postsurgical relapse. Five Class II malocclusion patients who underwent orthognathic surgery received BTX-A injections into both ABDM for the prevention of postoperative relapse. The relapse was evaluated using lateral cephalometric radiographs by comparing the postoperative cephalometric analyses at two different time points, postoperatively at 2 weeks (T1), and long-term, at 9 months after the surgical intervention (T2). The results demonstrated no significant differences between T2 and T1 for the Selle-Nasion-point A (SNA) angle, Selle-Nasion-point B (SNB) angle, point A-Nasion-point B (ANB) angle, mandibular length, and sagittal mandibular position. The patients exhibited stable occlusion without any signs of relapse after the surgery. A single BTX-A injection into the ABDM can effectively prevent postoperative relapse in Class II malocclusion patients, following orthognathic surgery. From a clinical perspective, in case of optimal dosage and procedure, BTX-A injection could be considered as the primary option for the prevention of postsurgical relapse for Class II malocclusion patients.

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.

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.

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.

Ultrasound dimensional changes of the anterior belly of the digastric muscle induced by orthognathic surgery and botulinum toxin A injection in Class II malocclusion

OBJECTIVES

The aim of the study is to evaluate the ultrasonographic dimensional changes of the anterior belly of the digastric muscle (ABDM), occurring after intramuscular botulinum toxin A (BTX-A) injection during orthognathic surgery, in a series of five Class II malocclusion patients.

METHODS

All the patients received 20 units of BTX-A, into both ABDM, intraoperatively. The length, width and cross-sectional area (CSA) of the ABDM were ultrasonographically measured at three different time points: T₀ (preoperatively), T₁ (postoperatively at 2 weeks after the surgical intervention), and T₂ (postoperatively at 6-9 months).

RESULTS

A statistically significant higher length of the ABDM was noted postoperatively, at T₁ and T₂ compared to T₀. The patients showed an increased length by 12.2% at 2 weeks postoperatively and continued to increase, reaching 24.6% at 6 months. A decreased width of ABDM by 6.5% at T₁ compared with T₀ was also found.

CONCLUSIONS

Postoperative ultrasound (US) follow-up measurements in patients with Class II malocclusion, orthognathic surgery and intraoperative BTX-A injection in the ABDM, showed dimensional changes of the muscle, with elongation and thinning. The muscular modifications were more pronounced at 6 months postoperatively, indicating consistency and potential benefit of using BTX-A in reducing the risk of surgical relapse. Further data on longer-term follow-up and larger number of cases are necessary.

Cerebral palsy and bruxism: Effects of botulinum toxin injections-A randomized controlled trial

Objective

Cerebral palsy (CP) includes disturbances in muscular control caused by perinatal brain injury. Masticatory muscle involvement hampers functions such as chewing and talking. Bruxism and temporomandibular disorders are overrepresented. Neuromuscular blocks with botulinum toxin type A (BTX‐A) may alleviate problems due to muscular hyperactivity. The aim was to evaluate masticatory muscle BTX‐A injections in subjects with CP and bruxism.

Methods

A prospective, parallel, randomized, placebo‐controlled, and double‐blind trial in 12 patients with CP was performed. End points were alterations in objective and subjective oral capacities after two BTX‐A or corresponding placebo injections. Matched, healthy references were also evaluated.

Results

The reference group demonstrated stronger and more efficient oral functions compared with the CP group. Subjective and objective oral capacities appeared to vary considerably between CP patients and also over time in this patient group and were poorly correlated. No significant effect of BTX‐A compared with placebo on outcome variables was observed at group level, but continued treatment with BTX‐A was requested by the majority of the patients.

Conclusion

The evidence is unable to support the use of BTX‐A for the treatment of affected masticatory muscles in CP, but the findings are inconclusive in certain respects. Larger, more homogeneous groups of CP patients need to be evaluated in future trials.

Effect of injection of botulinum toxin on decreasing the symptoms and signs of masticatory muscles in patients with temporomandibular dysfunction

Background. Temporomandibular joint dysfunction (TMD) is a term that describes problems in the masticatory system, including the temporomandibular joint, the dento-muscular system and the supporting bones. Injection of botulinum toxin, as a noninvasive technique, might be useful in decreasing symptoms such as muscular spasm, dystonia, migraine headaches and TMD. Therefore, the aim of the present study was to evaluate the effect of injection of botulinum toxin on decreasing the symptoms and signs of masticatory muscles in patients with TMD.

Methods. A total of 61 patients were consecutively included in the present study in 2016‒2017. All the subjects received a 50-unit injection of Dysport botulinum toxin in the masseter muscles using an extraoral injection technique. The results of the injection were evaluated in terms of pain severity using VAS, clinical evaluations of the joint click through palpation and by determining the inter-incisal distance. The patients underwent follow-up examinations at 1-week, 3-month and 6-month intervals after injection. Data were analyzed with appropriate statistical tests.

Results. Comparison of pain severity and articular clicks at different intervals showed decreases in these parameters over time, with significant differences between the time intervals (P<0.05). Comparison of mouth opening at different intervals showed increases in mouth opening over time.

Conclusion. The results of the present study showed that injection of botulinum toxin can be used in patients with TMD as a non-invasive treatment modality

Efficacy of botulinum toxin in the treatment of bruxism: Systematic review

BACKGROUND

Currently it has been shown that botulinum toxin is effective for a wide variety of medical conditions, and can be applied for therapeutic purposes as cosmetic. In recent years, there has been a growing trend in the use of this drug substance to control the muscular overactivity of bruxism. The objective of this study was the use of botulinum toxin type A (BTX-A) than traditional methods, by conducting a systematic review of randomized clinical trials (RCTs) published in the health sciences literature.

MATERIAL AND METHODS

An electronic search was made in the databases of the PubMed, Cochrane Library and Scopus data between March and October 2017, ECA, which will analyze the effect of botulinum toxin in the treatment of bruxism. We included studies of bruxist patients older than 18 years where BTX-A tests were performed on the masseter and / or temporal muscles and the control systems were injections of placebo (saline) or the use of traditional methods for the treatment of bruxism. such as occlusal splints, other medications or cognitive-behavioral therapy.

RESULTS

Of the 68 studies identified, 4 RCTs that fit our inclusion criteria were selected. These studies show that BTX-A injections can reduce the frequency of bruxism episodes, decrease pain levels and maximum occlusal force generated by this pathology, offer superior efficacy in the treatment of bruxism compared to control groups who were treated with placebo or with traditional methods for the treatment of bruxism.

CONCLUSION

Infiltrations with BTX-A are a safe and effective treatment for patients with bruxism, so its use is justified in daily clinical practice, especially in patients diagnosed with severe bruxism.

Mandibular bone effects of botulinum toxin injections in masticatory muscles in adult

OBJECTIVE

Botulinum toxin (BTX) is injected into masticatory muscles to treat various conditions. Animal studies have demonstrated bone loss at the condylar and alveolar regions of the mandible after BTX injection into masticatory muscles. The aim of the present study was to investigate mandibular bone changes in patients who received BTX injections in masticatory muscles.

STUDY DESIGN

Twelve adult patients who received BTX injections into masticatory muscles were included in this study. Cone beam computed tomography (CBCT) was performed before and 12 months after the injection. The condylar and alveolar regions of the mandible were analyzed by using texture analysis of the CBCT images with the run length method. Condylar cortical thickness was measured, and 3-dimensional analysis of the mandible was also performed. Six patients who did not receive BTX injections were used as controls.

RESULTS

A run length parameter (gray level nonuniformity) was found to be increased in condylar and alveolar bones. A significant cortical thinning was found at the anterior portion of the right condyle. Three-dimensional analysis showed significant changes in the condylar bone and at the digastric fossa. No changes in mandibular angles were found.

CONCLUSIONS

This study identified mandibular bone changes in adult patients who received BTX injection into masticatory muscles.

Evaluation of patient satisfaction after botulinum toxin A injection for the management of masticatory myofascial pain and dysfunction - A pilot study

Objective: To evaluate patient satisfaction with botulinum toxin type A injections for the management of masticatory myofascial pain and dysfunction. Methods: The study group included 25 patients with myofascial pain and dysfunction. Maximum mouth opening (MMO), measured with a ruler, and pain, measured on a 10-cm visual analog scale (VAS), were assessed before treatment and six weeks after treatment. Satisfaction with the treatment, measured on a 10-cm VAS, was obtained six weeks post-treatment. Results: The mean satisfaction score six weeks post-injection was 6.74/10, with a significant improvement in both MMO and pain. Satisfaction was positively correlated with a decrease in pain. Discussion: Botulinum toxin type A injections were well tolerated for the treatment of masticatory myofascial pain and dysfunction in patients with temporomandibular disorder. Improvements were observed in both MMO and pain, with most patients satisfied with the management of pain.

Orofacial pain - an update on diagnosis and management

The diagnosis and management of orofacial pain may be challenging due to complex histories, pathophysiology and associated psychosocial co-morbidities such as depression and anxiety. Neuropathic facial pain conditions such as burning mouth syndrome (BMS), persistent idiopathic facial pain (PIFP), atypical odontalgia (AO) and trigeminal neuralgia (TN) require early recognition by primary care clinicians and referral to secondary care. Acute pain-related temporomandibular disorder (TMD) may be managed in the primary care setting, with identification of those at risk of developing chronic TMD receiving an early referral to secondary care. Adopting a biopsychosocial approach, consisting of physical therapies, pharmacotherapy and psychological support can lead to effective management and may limit the negative impact of facial pain upon quality of life and daily functioning.

Use of a botulinum toxin A in dentistry and oral and maxillofacial surgery

Botulinum toxin (BT) was the first toxin to be used in the history of human medicine. Among the eight known serotypes of this toxin, those currently used in medicine are types A and B. This review article mainly discusses BT type A (BTA) because it is usually used in dentistry including dental anesthesiology and oral and maxillofacial surgery. BTA has been used mainly in the treatment of temporomandibular joint disorder (TMD) and hypertrophy and hyperactivity of the masticatory muscles, along with being a therapeutic option to relieve pain and help in functional recovery from dental and oral and maxillofacial surgery. However, it is currently used broadly for cosmetic purposes such as reducing facial wrinkles and asymmetry. Although the therapeutic effect of BTA is temporary and relatively safe, it is essential to have knowledge about related anatomy, as well as the systemic and local adverse effects of medications that are applied to the face.

Clinical outcomes of Botox injections for chronic temporomandibular disorders: do we understand how Botox works on muscle, pain, and the brain?

The main objective of this retrospective review was to analyze the clinical outcomes following the use of botulinum toxin (onabotulinumtoxinA, Botox) injections to relieve the symptoms of chronic temporomandibular disorders (TMD). Seventy-one patients with a diagnosis of TMD (according to the RDC/TMD international consortium) associated with or without bruxism and refractory to conventional treatment (e.g. oral appliances, physiotherapy, etc.) received Botox injections into the temporalis and masseter muscles. Subjective responses to Botox were categorized as 'beneficial' or 'not beneficial', as patient-reported outcomes based on the subjective reduction in pain and/or improvement in function. Fifty-five of the 71 subjects (77%) reported beneficial effects with Botox. Subjects with a concomitant bruxism diagnosis reported significant improvement over subjects without bruxism (87% vs. 67%; P=0.042). Subjects with stress-related psychiatric comorbidities and bruxism had a significantly higher benefit than those with stress-related psychiatric comorbidities alone (P=0.027). Patients reported less improvement if the time between the initial Botox injection and follow-up was less than an average of 5 weeks, compared to an average follow-up of 5-10 weeks (P=0.009). The subgroup TMD diagnosis and time interval post-injection are important predictors of patient-reported beneficial outcomes.

Botulinum toxin treatment for essential palatal tremors presenting with nasal clicks instead of pulsatile tinnitus: a case report

Background

In this study, we report a rare case of an adult patient with essential palatal tremors (EPT) presenting as nasal clicks, instead of otic clicks or objective pulsatile tinnitus in common EPT.

Case presentation

Nasal endoscopic examination and EMG recordings of the soft palate muscles were performed to confirm the source of the clicks. Initial treatment with lidocaine provided symptomatic relief for four hours. The patient was then treated with four simultaneous injections of 12.5 U of botulinum toxin in four different sites of the soft palate. Palatal tremors and clicks completely disappeared within three months of treatment.

Conclusions

To our knowledge, this is the first case of EPT that presented with nasal clicks. We recommend that otolaryngologists should expect this rare occurrence in the clinical setting, and handle patients presenting with such symptoms with care and compassion in order not to worsen their psychological status.

Electronic supplementary material

The online version of this article (doi:10.1186/s13005-016-0129-6) contains supplementary material, which is available to authorized users.

An Evaluation of Use of Botulinum Toxin Type A in the Management of Dynamic Forehead Wrinkles - A Clinical Study

INTRODUCTION

The pursuit of youth and beauty has undergone a resurgence of interest which is evidenced by increasing cosmetic procedures. Botulinum Toxin Type A (Botox) is one among the many procedures invented for facial rejuvenation which denervates certain muscles of facial expression responsible for facial wrinkles. It has been applied in the forehead, glabella, lateral canthal area and neck. In maxillofacial area hyperactive forehead wrinkles show sagging.

AIM

This study was aimed to clinically evaluate the efficacy of Botox injection in the elimination of hyperdynamic forehead wrinkles and the objectives were to compare pre-operative and post-operative improvement in the number of wrinkles, photographic grading and patient satisfaction responses after 1^st week, 4^th week and 16^th week.

MATERIALS AND METHODS

A total of 10 patients were randomly included in the present study who were cooperative, motivated and aesthetically conscious with moderate to severe forehead wrinkles. Assessment was performed clinically, photographically (using standardized photographs) and patient satisfaction responses were recorded at 1^st week, 4^th week and 16^th week.

RESULTS

The study showed a significant difference in the elimination of wrinkles at rest and in action when assessed at 1^st week and 4^th week and it was consistent at 16^th week. The patient showed positive satisfaction response without ptosis of the upper eyelid.

CONCLUSION

Treatment with Botox is simple, safe and an effective modality for reduction of forehead wrinkles. It offers an alternative management in a cost-effective way when compared to surgical procedures.

Applications of botulinum toxin in dentistry: A comprehensive review

The horizons of treatment options in dentistry are broadening rapidly. In this scenario, applications of unconventional treatment options like use of botulinum toxin (BT) are gaining momentum. The use of BT has been popularly accepted in esthetic procedures like management of facial wrinkles; however, it has been documented to be successful in a variety of conditions. Of particular interest to this paper are applications of BT in the maxillofacial region, concerned to dentistry. BT offers a transient, reversible, relatively safe treatment option to many conditions of interest to a dental practitioner. Dental surgeons by their virtue of being extensively aware of the anatomy of faciomaxillary region are a potential pool of operators who can use BT in their armamentarium with minor skill enhancement and thus widen the perspective of alternative, minimally invasive options to refractory conditions or invasive protocols.

Botulinum Toxin Type A as Preoperative Treatment for Immediately Loaded Dental Implants Placed in Fresh Extraction Sockets for Full-Arch Restoration of Patients With Bruxism

OBJECTIVES

The aim of the present report was to describe the use of Botulinum toxin type A as preoperative treatment for immediately loaded dental implants placed in fresh extraction sockets for full-arch restoration of patients with bruxism.

METHODS

Patients with bruxism who were scheduled to receive immediately loaded full-arch implant supported fixed restorations were included in this retrospective clinical report. To reduce the occlusal forces applied in patients with bruxism, Botulinum toxin type A was introduced prior to the implant placement procedure. Patients were followed and implant survival as well as peri-implant bone level was assessed in each periodic follow-up visit. Adverse effects were also recorded. A control group with no use of Botulinum toxin was evaluated as well.

RESULTS

A total of 26 patients (13 test and 13 control), with bruxism, aged 59.15 ± 11.43 years on average were included in this retrospective report and received immediately loaded dental implants placed in fresh extraction sockets for full-arch restoration. The test group treatment preceded by Botulinum toxin type A injection. Maxillary arches were supported by 8 to 10 implants while the mandibular arch was supported by 6 implants. All surgeries went uneventfully and no adverse effects were observed. The average follow-up time was 32.5 ± 10.4 months (range, 18-51). In the test group, no implant failures were recorded. One patient presented with 1 to 2 mm bone loss around 4 of the implants; the other implants presented with stable bone level. In the control group 1 patient lost 2 implants and another demonstrated 2 mm bone loss around 3 of the implants.

CONCLUSIONS

The preoperative use of Botulinum toxin in patients with bruxism undergoing full-arch rehabilitation using immediately loaded dental implants placed in fresh extraction sockets seems to be a technique that deserves attention. Further long-term, large-scale randomized clinical trials will help to determine the additional benefit of this suggested treatment modality.

The effect of laser and botulinum toxin in the treatment of myofascial pain and mouth opening: A randomized clinical trial

This study conducted a randomized clinical trial in 15 patients, who sought care at the Dental Clinic of the University of Passo Fundo, in order to compare the use of low-level laser and botulinum toxin in the treatment of myofascial pain and whether they alter the mouth opening of patients with temporomandibular disorder. The patients were divided into two groups: the Laser group received low-level GaAlAs laser, 100mW of power at a wavelength of 830nm in continuous light emission; and the Toxin group received 30U of botulinum toxin type A (BTX-A) in the first session, and 15U after fifteen days. The assessments were performed by measuring pain with Visual Analogue Scale (VAS), and mouth opening with a digital caliper. Data were submitted to Student's t test at 5% significance level. Regarding pain symptoms, the results indicate that groups treated with laser and toxin registered 7U in VAS, at day 5 the scores were 4.75 and 4.86U, respectively. The laser worked faster (day 12) at 2.75U, and the group treated with BTX-A registered 2.86U at day 30. Both therapies investigated were effective in reducing pain, but the effect of low-level laser was faster than the use of BTX-A. Both treatments showed no statistically significant improvement in mouth opening.

Pain-Related Temporomandibular Disorder - Current Perspectives and Evidence-Based Management

Pain-related temporomandibular disorder (TMD) is one of the top three most common chronic pain conditions, along with headaches and back pain. TMD has complex pathophysiology and significant associations with a variety of other chronic pain conditions, eg fibromyalgia, irritable bowel syndrome and migraine. Chronic TMD is associated with a negative impact upon quality of life and high levels of healthcare utility. It is important that clinicians are able to diagnose TMD correctly, provide appropriate management in keeping with current evidence-based practice, and identify when to refer patients to specialist care. The presence of risk factors, eg anxiety, depression, pain-related disability and chronic pain conditions elsewhere in the body, may help to identify which TMD patients require referral for multidisciplinary management. TMD should be managed using a holistic approach, incorporating patient education and encouragement towards self-management. TMD care pathways should consider using the three'pillars'of pain management: physical therapies, pharmacotherapy and clinical psychology.

Botulinum neurotoxin type A in the masseter muscle: effects on incisor eruption in rabbits

INTRODUCTION

Botulinum neurotoxins are responsible for the paralytic food poisoning, botulism. Commercial formulations such as botulinum neurotoxin type A are increasingly used for various conditions, including cosmetic recontouring of the lower face by injection of the large masseter muscles. The paralysis of a major muscle of mastication lowers occlusal force and thus might affect tooth eruption. The purpose of this study was to investigate the effects of unilateral masseter muscle injection of botulinum neurotoxin type A on the rate of eruption of incisors in a rabbit model. We hypothesized that the teeth would overerupt in an underloaded environment.

METHODS

Forty rabbits were injected with either botulinum neurotoxin type A or saline solution in 1 masseter muscle. Mastication and muscle force production were monitored, and incisor eruption rate was assessed by caliper measurement of grooved teeth.

RESULTS

The injection of saline solution had no effect. The masseter muscle injected with botulinum neurotoxin type A showed a dramatic loss of force 3 weeks after injection despite apparently normal mastication. Incisor eruption rate was significantly decreased for the botulinum neurotoxin type A group, an effect attributed to decreased attrition.

CONCLUSIONS

This study has implications for orthodontics. Although findings from ever-growing rabbit incisors cannot be extrapolated to human teeth, it is clear that botulinum neurotoxin type A caused a decrease in bite force that could influence dental eruption.

Myofascial pain of the jaw muscles: comparison of short-term effectiveness of botulinum toxin injections and fascial manipulation technique

A randomized controlled trial was performed to compare the short-term effectiveness of botulinum toxin injections and physiatric treatment provided by means of Fascial Manipulation techniques in the management of myofascial pain of jaw muscles. Thirty patients with a Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) diagnosis of myofascial pain were randomized to receive either single-session botulinum toxin injections (Group A) or multiple-session Fascial Manipulation (Group B). Maximum pain levels (VAS ratings) and jaw range of motion in millimeters (maximum mouth opening, protrusion, right and left laterotrusion) were assessed at baseline, at the end of treatment, and at a three-month follow-up. Both treatment protocols provided significant improvement over time for pain symptoms. The two treatments seem to be almost equally effective, Fascial Manipulation being slightly superior to reduce subjective pain perception, and botulinum toxin injections being slightly superior to increase jaw range of motion. Differences between the two treatment protocols as to changes in the outcome parameters at the three-months follow-up were not relevant clinically. Findings from the present investigation are in line with literature data supporting the effectiveness of a wide spectrum of conservative treatment approaches to myofascial pain of the jaw muscles. Future studies on larger samples over a longer follow-up span are needed on the way to identify tailored treatment strategies.

Botulinum toxin in masticatory muscles: short- and long-term effects on muscle, bone, and craniofacial function in adult rabbits

Paralysis of the masticatory muscles using botulinum toxin (BTX) is a common treatment for cosmetic reduction of the masseters as well as for conditions involving muscle spasm and pain. The effects of this treatment on mastication have not been evaluated, and claims that the treatment unloads the jaw joint and mandible have not been validated. If BTX treatment does decrease mandibular loading, osteopenia might ensue as an adverse result. Rabbits received a single dose of BTX or saline into one randomly chosen masseter muscle and were followed for 4 or 12 weeks. Masticatory muscle activity was assessed weekly, and incisor bite force elicited by stimulation of each masseter was measured periodically. At the endpoint, strain gages were installed on the neck of the mandibular condyle and on the molar area of the mandible for in vivo bone strain recording during mastication and muscle stimulation. After termination, muscles were weighed and mandibular segments were scanned with micro CT. BTX paralysis of one masseter did not alter chewing side or rate, in part because of compensation by the medial pterygoid muscle. Masseter-induced bite force was dramatically decreased. Analysis of bone strain data suggested that at 4 weeks, the mandibular condyle of the BTX-injected side was underloaded, as were both sides of the molar area. Bone quantity and quality were severely decreased specifically at these underloaded locations, especially the injection-side condylar head. At 12 weeks, most functional parameters were near their pre-injection levels, but the injected masseter still exhibited atrophy and percent bone area was still low in the condylar head. In conclusion, although the performance of mastication was only minimally harmed by BTX paralysis of the masseter, the resulting underloading was sufficient to cause notable and persistent bone loss, particularly at the temporomandibular joint.

Effectiveness of botulinum toxin type A treatment of neck pain related to nocturnal bruxism: a case report

OBJECTIVE

This case report describes a patient with nocturnal bruxism and related neck pain treated with botulinum toxin type A (BTX-A).

CLINICAL FEATURES

The patient was a 27-year-old man with nocturnal bruxism and difficulty in active mouth opening and chewing and neck pain at rest. His numeric pain score was 7 of 10. Surface electromyography of the temporalis and masseter muscles showed typical signs of hyperactivity, characterized by compound muscle action potential amplitude alterations.

INTERVENTION AND OUTCOME

After clinical evaluation, he was treated with BTX-A to reduce masseter and temporalis muscle hyperactivity. After 3 days of treatment with BTX-A, with each masseter muscle injected with a dose of about 40 mouse units with a dilution of 1 mL and with temporal muscle bilaterally injected with 25 mouse units with the same dilution, a decrease in bruxism symptoms was reported. Neck pain also decreased after the first treatment (visual analog scale of 2/10) and then resolved completely. After 4 weeks, electromyography showed the reduction of muscle hyperactivity with a decrease in the amplitude of the motor action potential. The same reduction in signs and symptoms was still present at assessment 3 months posttreatment.

CONCLUSION

These findings suggest that BTX-A may be a therapeutic option for the treatment of bruxism and related disorders.

Pathophysiology of TMD pain--basic mechanisms and their implications for pharmacotherapy

This article discusses the pathophysiology of temporomandibular disorders (TMD)-related pain and its treatment with analgesic drugs. Temporomandibular disorders are comprised of a group of conditions that result in temporomandibular joint pain (arthralgia, arthritis) and/or masticatory muscle pain (myofascial TMD). In at least some patients with TMD, a peripheral mechanism contributes to this pain. However, there is often a poor correlation between the severity of TMD-related pain complaints and evidence of definitive tissue pathology. This has led to the concept that pain in some patients with TMD may result from altered central nervous system pain processing and further that this altered pain processing may be attributable to specific genes that are heritable. Psychosocial stressors are also thought to contribute to the development of TMD-related pain, particularly masticatory muscle pain. Finally, substantially more women suffer from TMD than men. Although there are arguably multiple reasons for sex-related differences in the prevalence of TMD, one candidate for the increased occurrence of this disorder in women has been suggested to be the female sex hormone oestrogen. Analgesic drugs are an integral part of the primary treatment for TMD-related pain and dysfunction with more that 90% of treatment recommendations involving use of medications. The most commonly used agents include non-steroidal anti-inflammatory drugs, corticosteroids, muscle relaxants, anxiolytics, opiates and tricyclic antidepressants, however, evidence in support of the effectiveness of these drugs is lacking. Continued research into the pathophysiology of TMD-related pain and the effectiveness of analgesic treatments for this pain is required.