Application of botulinum toxin in maxillofacial field: part I. Bruxism and square jaw

A Multicenter Phase II Study Evaluating the Safety and Efficacy of Botulax in Asian Patients with Benign Masseteric Hypertrophy

BACKGROUND

Benign masseteric hypertrophy (BMH) is a condition in which the thickness of the masseter muscle is increased, resulting in jawline prominence with an undesirable cosmetic appearance. Botulinum toxin type A (BTA) injection is a promising treatment option, but its effective dose remains debated.

METHODS

Adults older than 19 diagnosed with BMH through visual examination and palpation related to a masseter muscle prominence were selected, and 80 patients were randomly assigned into five groups (placebo group and four groups with different doses of BTA: 24 U, 48 U, 72 U, or 96 U, on both sides of the jaw) and treated with placebo or BTA once at their baseline visit. During each follow-up, the treatment efficacy was evaluated with ultrasound examination of the masseter muscle, three-dimensional facial contour analysis, visual evaluation by the investigator, and patient satisfaction evaluation.

RESULTS

The mean age of the 80 patients was 42.7 ± 9.98 years; 68.75% were women. The mean change in masseter muscle thickness during the maximum clenching state after 12 weeks of drug administration compared with baseline in the 24-U, 48-U, 72-U, and 96-U groups were -2.33 ± 0.41 mm, -3.35 ± 0.42 mm, -2.86 ± 0.42 mm, and -3.79 ± 0.42 mm, respectively. All treatment groups showed a statistically significant decrease compared with placebo. Regarding subjective satisfaction, all treatment groups, except the 24-U group at 4 weeks, showed higher satisfaction than the placebo group during all visits. No significant adverse events were noted.

CONCLUSION

BTA administration of at least 48 U for BMH is more cost-effective than high-dose units and has a low risk of side effects.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, II.

Botulinum Toxin for the Management of Pelvic Floor Tension Myalgia and Persistent Pelvic Pain: A Systematic Review and Meta-analysis

OBJECTIVE

To systematically review the literature on use of botulinum toxin to treat pelvic floor tension myalgia and persistent pelvic pain.

DATA SOURCES

The ClinicalTrials.gov , PubMed, EMBASE, and Scopus databases were searched from inception to November 2022 by two independent assessors (B.L.K. and F.G.L.). Identified studies were screened by title and abstract and included after full-text review. Data extraction was subsequently performed and recorded in Microsoft Excel.

METHODS

This study was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines after registration in PROSPERO (CRD42022289132). All randomized studies, prospective studies with more than five participants, and retrospective studies with more than 10 participants published in English or French and assessing the use of botulinum toxin for the treatment of pelvic floor tension myalgia and persistent pelvic pain in women were included. Meta-analyses were performed on randomized data.

TABULATION, INTEGRATION, AND RESULTS

Of 4,722 articles identified, 24 satisfied inclusion criteria. A meta-analysis of five randomized controlled trials totaling 329 participants demonstrated no differences in patient- and clinician-reported outcome measures, including pain, dyspareunia, sexual function, and vaginal manometry. Mean duration of follow-up was 6 months. A qualitative analysis of 14 prospective and four retrospective studies including 804 participants is supportive of botulinum toxin; however, the quality of data is low, and there is marked heterogeneity between studies.

CONCLUSION

Meta-analyses of randomized data do not support the use of botulinum toxin to treat pelvic floor tension myalgia and persistent pelvic pain. Failure of these data to confirm the findings of nonrandomized prospective studies that suggest a treatment benefit may be attributable to the absence of placebo control and confounding outcomes obtained from an active comparator group. Further randomized controlled trials with true placebo are strongly recommended.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42022289132.

Mechanism and clinical use of botulinum neurotoxin in head and facial region

PURPOSE

Botulinum neurotoxin (BoNT) is a biological toxin produced by Clostridium botulinum. BoNT is a potent toxin extensively used in therapeutic interventions. This review provides an updated overview of the mechanisms of action and clinical applications of BoNT in head and facial region.

STUDY SELECTION

MEDLINE/PubMed searches were conducted using the terms "botulinum neurotoxin" and "dentistry" along with a combination of other related terms. In addition, studies were manually selected from reference lists of the selected articles.

RESULTS

The Food and Drug Administration in the United States initially approved BoNT to treat strabismus, blepharospasm, and hemifacial spasms. The use of BoNT in dermatology and cosmetics has been widely established and has created a revolution in these fields. Over the years, its applications in various medical specialties have expanded widely. Owing to its safety, efficacy, and long duration of action, it is well-accepted by patients. BoNT/A and BoNT/B are widely used in clinical practice. Several off-label uses of BoNT in the dental fraternity have yielded promising results. We have elaborated on the speculated mechanism of action, dosage, effective sites of injection, and adverse effects of each therapeutic application. The various clinical indications for BoNT include bruxism, myofascial pain, temporomandibular joint dislocation, hemifacial pain, orofacial dystonia, facial paralysis, chronic migraine, and trigeminal neuralgia.

CONCLUSIONS

BoNT is a safe treatment that can be used effectively, provided that the clinician has adequate knowledge regarding the mechanism, injection techniques, and local and systemic side effects and that it is administered cautiously and purposefully.

Clinical investigation of botulinum toxin (prabotulinumtoxin A) for bruxism related to masseter muscle hypertrophy: A prospective study

This study aims to confirm the effectiveness and safety of a prabotulinumtoxin type A (praBTX-A) injection in patients with bruxism and masseter hypertrophy. The study included patients who ground or clenched their teeth while sleeping and had computed tomography (CT) scans that showed a maximum thickness of the masseter muscle of 15 mm or more. The praBTX-A was administered bilaterally into the masseter muscles; 15 U/side for group 1, 25 U/side for group 2, and 35 U/side for group 3. CT scans and bruxism questionnaires were conducted before and eight weeks after the injection. Thirty-seven patients were enrolled, but three dropped out due to loss of follow-up. After injection, masseter thickness decreased to 15.1 ± 2.0 mm for group 1, 14.3 ± 2.9 mm for group 2, and 13.4 ± 1.8 mm for group 3 (p = 0.043). Group 3 showed a statistically significant lower masseter thickness compared to group 1 (p = 0.039). Both subjective and objective frequencies of bruxism decreased for all groups, but there were no significant differences in either subjective (p = 0.396) or objective frequencies (p = 0.87) between the groups after the injection. The results of this study suggest that praBTX-A injection is a safe and effective treatment for bruxism and masseter hypertrophy. A dosage of 35 IU/side can effectively decrease masseter thickness and relieve bruxism symptoms. Even the minimum dosage of 15 IU/side can contribute to improvements in bruxism symptoms. This investigation provides valuable information for managing bruxism that is associated with hypertrophic masseter muscles.

Cosmetic Treatment Using Botulinum Toxin in the Oral and Maxillofacial Area: A Narrative Review of Esthetic Techniques

Botulinum toxin (BoNT) is an anaerobic rod-shaped-neurotoxin produced by Clostridium botulinum, that has both therapeutic and lethal applications. BoNT injection is the most popular cosmetic procedure worldwide with various applications. Patients with dynamic wrinkles in areas such as the glabella, forehead, peri-orbital lines, nasal rhytides, and perioral rhytides are indicated. Excessive contraction of muscles or hyperactivity of specific muscles such as bulky masseters, cobble stone chins, gummy smiles, asymmetric smiles, and depressed mouth corners can achieve esthetic results by targeting the precise muscles. Patients with hypertrophic submandibular glands and parotid glands can also benefit esthetically. There are several FDA-approved BoNTs (obabotuli-numtoxinA, abobotulinumtoxinA, incobotulinumtoxinA, letibotulinumtoxinA, prabotulinumtox-inA, daxibotulinumtoxinA, rimbotulinumtoxinB) and novel BoNTs on the market. This paper is a narrative review of the consensus statements of expert practitioners and various literature on the injection points and techniques, highlighting both the Asian and Caucasian population separately. This paper can serve as a practical illustrative guide and reference for optimal, safe injection areas and effective doses for application of BoNT in the face and oral and maxillofacial area. The history of BoNT indications, contraindications, and complications, and the merits of ultrasonography (US)-assisted injections are also discussed.

Botulinum Toxin Injection for Masseteric Hypertrophy Using 6 Point Injection Technique - A Case Report. Proposal of a Clinical Technique to Quantify Prognosis

Introduction

Masseter hypertrophy presents as unilateral or bilateral swellings over the ramus and angle of the mandible. It is caused by malocclusion, clenching, TMJ disorders, etc and alters facial symmetry, leading to discomfort and negative cosmetic impact in many patients, making this a popular request for aesthetic and functional correction.

Materials and Methods

This case report involves injecting Botulinum toxin into 6 equidistant bulging points on the masseter. Standardized photography and clinical parameters were used to assess facial contour and masseter muscle thickness at baseline and successive follow ups.

Results and Discussion

Significant masseteric bulk reduction was observed in subsequent follow ups.

Conclusion

The 6-point technique was found to be an effective treatment modality for Botox injection in masseteric hypertrophy. The clinical method to quantify prognosis was easy and economical.

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.

Application of Botulinum Toxin in Patients with Secondary Otalgia Caused by Bruxism

Aim

The aim of this study was to determine the effectiveness of botulinum toxin administration in patients who consulted the otolaryngology clinic with secondary otalgia caused by bruxism.

Introduction

Botulinum toxin can be applied to the hypertrophic muscles in patients who suffer from facial asymmetry even though they do not experience pain. Injection intervals and the condition of the muscles should be monitored as botulinum toxin applications to the muscles may result in decreased muscle strength and chewing difficulties.

Methods

This prospective study was conducted with bruxism patients at Private Kesan Hospital otorhinolaryngology outpatient clinic between August 2019 and December 2019. The diagnosis was based on the anamnesis and physical examination of the patient. The Visual Analogue Scale was used to evaluate patients' pain levels throughout the treatment.

Results

A total of 37 patients, between 19 and 51 years old, 22 (59.46%) females and 15 (40.54%) males, who consulted to the otolaryngology clinic in Private Kesan Hospital between August 2019 and December 2019 with a diagnosis of otalgia caused by bruxism were included in the study. Nine patients (24.3%) had facial asymmetry due to masseter muscle hypertrophy. The average age of the participants was 34.00 ± 9.13 years old. Two weeks after the application of botulinum toxin, patients' complaints subsided. In patients with facial asymmetry, it was observed that asymmetry decreased after the 2nd month and noticeably improved after the 4th month.

Discussion

Bruxism should be considered in the differential diagnosis of patients with ear pain. Botulinum toxin can be applied in patients who do not respond adequately to classical treatments such as medical treatments, chewing training, neck and facial muscle relaxation techniques, psychological support, and dental splint applications.

Three-Dimensional Bone Block Planning for Mandibular Sagittal Bone Defect Reconstruction

Bone defects seen in severe sagittal discrepancies between the maxilla and mandible do not solely qualify for orthodontic treatment. An interdisciplinary approach with the aid of a surgical, orthodontic, and periodontal team should be implemented in the treatment of such cases. Despite the use of standard treatment methods, the therapy is always planned and carried out individually for each patient. The surgical treatment of bone defects in the area of the jawbones is associated with a number of potential complications. Regenerative medicine, which has already been practiced in reconstructive surgery, is now gradually receiving more attention in the treatment of orthognathic defects. We developed a method for the reconstruction of the alveolar bone in the sagittal dimension using 3D allogenic graft blocks, as a preparing feature in the orthodontic treatment of borderline cases or as a treatment option for complications arising during general orthodontic treatment.

Efficacy and Safety of Botulinum Toxin vs. Placebo in Depression: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Major depressive disorder (MDD) is a serious mental disorder that represents a substantial public health problem. Several trials have been undertaken to investigate the role of botulinum toxin type A (BTX-A) in the treatment of MDD, but the conclusions were controversial. To examine the efficacy and safety of BTX-A vs. placebo on patients with a clinical diagnosis of MDD, we conducted this systematic review and meta-analysis. Methods: A systematic search was conducted for all relevant randomized controlled trials (RCTs) in PubMed and Web of Science from inception to June 17, 2020. All published studies that investigated the efficacy and safety of BTX-A injections on patients with a clinical diagnosis of MDD were included. The overall effect size was summarized using a random-effects meta-analysis model. The primary outcomes of the present meta-analysis were the changes in depressive rating scale at week 6 after BTX-A injection compared with placebo. The safety of BTX-A injections also was assessed. Results: Five RCTs with a total of 417 participants (189 patients in the BTX-A group, 228 patients in placebo group) were eligible in this meta-analysis. The results indicated an overall positive effect of BTX-A injections for reducing the depressive symptoms of patients with MDD (Hedges' g, -0.82; 95% CI, -1.38 to -0.27) with large effect size. Differences are likely explained by the dose of BTX-As and the gender of the participants. Our findings also highlighted that BTX-A injections were generally well-tolerated, with only mild and temporary adverse events reported. Conclusions: The present meta-analysis provides evidence that BTX-A injections are associated with a statistically significant improvement in depressive symptoms. BTX-A injections are generally safe and may provide a new, alternative option for the treatment of depression.