The basic science of botulinum toxin

A Standardized Technique for Gummy Smile Treatment Using Repeated Botulinum Toxins: A 1-year Follow-up Study

The present study was performed to evaluate the effect of repeated botulinum toxin injections and their long-term effects, using a customized injection point and dosage technique in the treatment of excessive gingival display. Twenty women who had gummy smile due to hypermobility of the upper lip or gingival display, ranging from 4 to 6 mm' were included in the study. All patients were injected with Botox injections at different injection points according to the type of smile. Pre- and postoperative measurements were taken by measuring digitally the gingival display at smiling, using Adobe Photoshop software via standardized digital photographs. Patients were followed up at 14 days, 4 months, 8 months, and 12 months. Postoperative measurements showed marked improvement at 14-day follow-up, with a significant reduction in the amount of gingival display. Relapse, however, occurred at 4 months and later. For excessive gingival display, Botox is an effective treatment that lasts for 2-3 months, with almost complete relapse at 4 months. We concluded from the results of our study that, despite repeated Botox injections at two follow-up intervals (4 and 8 months), the theory that repeated Botox injections may offer a permanent effect is still questionable.

A Review of Complications Due to the Use of Botulinum Toxin A for Cosmetic Indications

BACKGROUND

Botulinum toxin A (botulinum toxin A) was found to provide a wide variety of therapeutic and aesthetic benefits as one of the most potent toxins in the world. Injectable remedies, including soft tissue fillers and botulinum toxin, have become very common in wrinkling and face rejuvenation management. While these methods of treatment are relatively safe, serious side effects can occur. In this review, the complications of BoNTA are highlighted.

METHODS

A literature research considered published journal articles (clinical trials or scientific reviews). Electronic databases (PubMed, Scopus, Science Direct) were searched using key terms, and for identification of additional relevant studies, reference lists have also been examined. Only articles published in English were included in this review with a time restriction from 2000 to 2020.

RESULTS

There are various injection-related adverse effects associated (AE) with botulinum toxins such as erythema, oedema, pain, ptosis of eyelid or brow and ecchymosis. The overall majority of adverse events identified are mild and temporary.

CONCLUSION

As the use of toxins becomes increasingly more common, adverse events can be expected to increase as well. The practitioners need to be aware of such AEs, and the patients should be informed of these before undertaking such procedures.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Botulinum Toxin Application in Facial Esthetics and Recent Treatment Indications (2013-2018)

Background

Ever-changing perception of beauty from childhood to old age is changing with the revolution in cosmeceuticals science. Esthetics is an individual's perception since time immemorial. Standards of beauty have changed through centuries with increased awareness about esthetics. The face remains main source of information for identification and discrimination. It constitutes a structural ground for many nonverbal messages including the emotional state of a person, so the proverb "Face is an index of mind" holds good. The wrinkles and laxity are considered to be one of the factors for aging. Hence, escalating demand for cosmetic treatment to reduce facial wrinkles and laxity has stimulated us to search for published literature for nonsurgical techniques for enhancement of facial beauty. The review analyzed the published data to provide narrative basic review in a concise way to the beginners, clinicians, and students.

Materials and Methods

We have adopted search criteria using keywords: Botox, Botulinum toxin, incobotulinumtoxinA, esthetics, face, uses of Botox, with various Boolean operators and or in title, and abstract using PubMed search engine. The database search limited to PubMed only from January 2013 to June 2018.

Results

Various search results have been appended as annexures at the end of the article for further reference for the readers. Finally, 17 references were selected to write narrative review to meet our objectives.

Conclusion

The advancing front in the use of toxins is an emerging science for the beautification of a face. Botox exploded in to market because of efficacy, tolerability, and minimally invasive nature. The present review gives brief about the history of Botulinum toxin, types, mechanism of action, clinical indications, preparations, storage, and technique for various uses with a brief note on patient selection, contraindications, and complications.

Comparison of botulinum neurotoxin type A formulations in Asia

Results

All protein-based therapeutics, such as botulinum neurotoxin type A (BoNT/A), are potentially immunogenic and can lead to anaphylaxis, autoimmunity, or diminished or complete absence of therapeutic efficacy, especially if administered repeatedly. Therefore, the protein quantity in BoNT/A products is an important consideration when selecting products for treatment. However, essential formulation data are not always publicly accessible.

Materials and methods

The neurotoxin protein content of products newly introduced in Asia, such as (listed alphabetically) Botulax^®, Meditoxin^®, Nabota^®, and Relatox^®, was measured by sandwich enzyme-linked immunosorbent assay with antisera directed against BoNT/A compared to Xeomin^®.

Results

Compared to Xeomin with no inactive neurotoxin, although Botulax and Nabota contained 844 and 754 pg of neurotoxin protein, respectively, the percentage of inactive neurotoxin was calculated to be 103 and 81, respectively, while the potency per pg of neurotoxin was 0.118 and 0.133 U, respectively. Meditoxin and Relatox had 575 and 578 pg of neurotoxins, respectively, marginally higher than that of Xeomin, while the percentage of inactive neurotoxins was 38 and 33, respectively, and the potency per pg of neurotoxin was 0.174 and 0.173 U, respectively. However, Xeomin, which has 416 pg/vial of purified neurotoxin and 0.240 U of efficacy per pg of neurotoxin, has the lowest neurotoxin protein content and consequently the highest specific potency compared to the four Asian BoNT/A preparations in this study.

Conclusion

Although Botulax and Nabota had more neurotoxin than Xeomin in an equivalent volume, they contained greater amounts of inactive neurotoxin. In addition, although Meditoxin and Relatox had slightly more neurotoxin than Xeomin, both contained greater amounts of inactive neurotoxin.

The application of W-plasty combined Botox-A injection in treating sunk scar on the face

This study was aimed to explore the effect of W-plasty combined Botox-A injection in improving appearance of scar.According to the inclusive and exclusive criteria, patients received W-plasty combined Botox-A injection (study group) or traditional (control group) scar repairment were enrolled in this study. After surgery, a follow-up ranged from 1 to 2 years was conducted. The effectiveness of surgery was assessed by visual analogue scale (VAS).A total of 38 patients were enrolled in this study, including 21 cases in the study group and 17 cases in the control group. There were no significant difference were identified in age (t = 0.339, P = .736), gender ratio (χ = 0.003, P = .955) and scar forming reason (χ = 0.391, P = .822) between 2 groups. After treatment, the VAS score in the study group was significantly higher than that in the control group (P < .001).W-plasty combined Botox-A injection can significantly improve the appearance of sunk scar on the face.

Botulinum Toxin Type A: Assessing The Effects on The Brain Stem

BACKGROUND

In this study, our aim is to investigate the possible effects of Botulinum toxin type A administrations in the early and late periods on the brain stem.

METHODS

Eighteen white New Zealand rabbits were used in this study with the subjects being divided into three groups. Group I received 0.05 mL sterile saline to the left anterior auricular muscles. Group II and III were injected with Botulinum toxin type A (Botox, Allergan) to the left anterior auricular muscles. Group II was sacrificed 5 days after application and Group III was sacrificed 12 weeks after application; brain stem tissues were then taken. The samples were examined with Caspase 3, 8, and 9 immunohistochemical stainings.

RESULTS

In the control group with Caspase-3 immune staining, moderate-to-strong immune reactivity was seen in a small number of neurons. In the Caspase-8 and 9 immune stainings, the immune reactive neurons were seen in greater numbers when compared with the Caspase-3 immune reactive neurons. In the early and late period, groups with Caspase-8 and 9 immune stainings, the immune reactive neurons were seen in greater numbers and in the wider area when compared with the Caspase-3 immune reactive neurons. No significant differences were recognized in the Caspase immune stainings between the early and late period groups. The results were statistically supported.

CONCLUSION

It was concluded that Botulinum toxin type A application did not trigger apoptosis in stem cell tissues.

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Botulinum toxin in the management of head and neck disorders

Botulinum toxin is a polypeptide protoxin synthesized by Clostridium botulinum that results in localized reduction of muscle activity by inhibiting acetylcholine release at the neuromuscular junction. In 2004, the US Food and Drug Administration approved its application in the treatment of various medical conditions, such as facial wrinkles, strabismus, cervical dystonia, blepharospasm, and hyperhidrosis. Later, its application extended to improving dental esthetics and gummy smile. It was found to be a safe and effective alternative to medical therapy to treat various head and neck disorders that have a neurologic component. In this review, we will highlight the mechanism of action and therapeutic benefits of botulinum toxin in the management of head and neck disorders.

Botulinum Toxin Type A and the Prevention of Hypertrophic Scars on the Maxillofacial Area and Neck: A Meta-Analysis of Randomized Controlled Trials

Background

The purpose of the meta-analysis was to evaluate the efficiency of therapeutic botulinum toxin type A (BTX-A) in the prevention of maxillofacial and neck scars.

Methods and Findings

Information came from the following electronic databases: Medline, PubMed, Cochrane Library, and EMBASE (time was ended by August 31, 2015) to retrieve RCTs evaluating the effect of the BTX-A for hypertrophic scar on the maxillofacial or neck. All languages were included as long as they met the inclusion criteria. Here the effects of BTX-A were evaluated by comparing the width of the scar, patient satisfaction, and the visual analysis scores (VAS), respectively. Pooled weighted mean differences (WMDs), pooled odds ratios (ORs), and 95% confidence intervals (CI) were calculated. Nine RCTs covering a total of 539 patients were included. A statistically significant difference in scar width was identified between the BTX-A group and control group (non-BTX-A used) (WMD = -0.41, 95% CI = -0.68 to -0.14, P = 0.003). A statistically significant difference in patient satisfaction was observed between the BTX-A group and control group (OR = 25.76, 95% CI = 2.58 to 256.67, P = 0.006). And in patients regarding visual analysis scores (VAS), a statistically significant difference was also observed between the BTX-A group and control group (WMD = 1.30, 95% CI = 1.00 to 1.60, P < 0.00001).

Conclusions

This meta-analysis evaluates the efficacy of the BTX-A and confirms that BTX-A is a suitable potential therapy for the prevention of hypertrophic scars in patients in the maxillofacial and neck areas.

Botulinum toxin the poison that heals: A brief review

Botulinum neurotoxins, causative agents of botulism in humans, are produced by Clostridium botulinum, an anaerobic spore-former Gram-positive bacillus. Botulinum neurotoxin poses a major bioweapon threat because of its extreme potency and lethality; its ease of production, transport, and misuse; and the need for prolonged intensive care among affected persons. This paper aims at discussing botulinum neurotoxin, its structure, mechanism of action, pharmacology, its serotypes and the reasons for wide use of type A, the various indications and contraindications of the use of botulinum neurotoxin and finally the precautions taken when botulinum neurotoxin is used as a treatment approach. We have searched relevant articles on this subject in various medical databases including Google Scholar, PubMed Central, ScienceDirect, Wiley Online Library, Scopus, and Copernicus. The search resulted in more than 2669 articles, out of which a total of 187 were reviewed. However, the review has been further constricted into only 54 articles as has been presented in this manuscript keeping in mind the page limitation and the limitation to the number of references. A single gram of crystalline toxin, evenly dispersed and inhaled, can kill more than one million people. The basis of the phenomenal potency of botulinum toxin (BT) is enzymatic; the toxin is a zinc proteinase that cleaves neuronal vesicle-associated proteins responsible for acetylcholine release into the neuromuscular junction. A fascinating aspect of BT research in recent years has been the development of the most potent toxin into a molecule of significant therapeutic utility. It is the first biological toxin which is licensed for the treatment of human diseases. The present review focuses on both warfare potential as well as medical uses of botulinum neurotoxin.

Therapeutic applications of botulinum neurotoxins in head and neck disorders

Objective

The aim of this article is to review the mechanism of action, physiological effects, and therapeutic applications of botulinum neurotoxins in the head and neck area.

Study design

An extensive literature search was performed using keywords. The resulting articles were analyzed for relevance in four areas: overview on botulinum neurotoxins, the role of botulinum neurotoxins in the management of salivary secretory disorders, the role of botulinum neurotoxins in the management of facial pain, and the role of botulinum neurotoxins in head and neck movement disorders. Institutional review board approval was not needed due the nature of the study.

Results

Botulinum neurotoxin therapy was demonstrated to be a valuable alternative to conventional medical therapy for many conditions affecting the head and neck area in terms of morbidly, mortality, and patient satisfaction with treatment outcomes.

Conclusion

Botulinum neurotoxin therapy provides viable alternatives to traditional treatment modalities for some conditions affecting the head and neck region that have neurological components. This therapy can overcome some of the morbidities associated with conventional therapy. More research is needed to determine the ideal doses of botulinum neurotoxin to treat different diseases affecting the head and neck regions.

A morphological evaluation of botulinum neurotoxin A injections into the detrusor muscle using magnetic resonance imaging

OBJECTIVES

Although botulinum neurotoxin type A (BoNT/A) intradetrusor injections are a recommended therapy for neurogenic detrusor overactivity (NDO), refractory to antimuscarinic drugs, a standardisation of injection technique is missing. Furthermore, some basic questions are still unanswered, as where the toxin solution exactly spreads after injection. Therefore, we investigated the distribution of the toxin solution after injection into the bladder wall, using magnet resonance imaging (MRI).

METHODS

Six patients with NDO were recruited. Three of six patients received 300 U of BoNT/A + contrast agent distributed over 30 injection sites (group 1). The other three patients received 300 U of BoNT/A + contrast agent distributed over 10 injection sites (group 2). Immediately after injection, MRI of the pelvis was performed. The volume of the detrusor and the total volume of contrast medium inside and outside the bladder wall were calculated.

RESULTS

In all patients, a small volume (mean 17.6%) was found at the lateral aspects of the bladder dome in the extraperitoneal fat tissue, whereas 82.4% of the injected volume reached the target area (detrusor). In both groups there was a similar distribution of the contrast medium in the target area. A mean of 33.3 and 25.3% of the total detrusor volume was covered in group 1 and 2, respectively. Six weeks after injection, five of six patients were continent and showed no detrusor overactivity in the urodynamic follow-up. No systemic side effects were observed.

CONCLUSIONS

Our results provide morphological arguments that the currently used injection techniques are appropriate and safe.

Effect of Fresh and Stored Botulinum Toxin A on Muscle and Nerve Ultrastructure

The aim of this study was to compare the ultrastructural alterations of the muscle and nerve that appear following injection of freshly reconstituted and stored botulinum toxin A. Fifteen New Zealand white rabbits were assigned to 6 groups, and anterior auricular muscle was used for injections. Group 1 did not receive any injection and group 2 received saline injection. Groups 3 and 5 received fresh botulinum; muscles and motor nerves were harvested at 5 days and 12 weeks, respectively. Groups 4 and 6 received stored botulinum; muscles and motor nerves were harvested at 5 days and 12 weeks, respectively. Alterations in muscle and nerve ultrastructure were evaluated with electron microscopy. Degeneration findings in muscle after botulinum toxin injection revealed no significant difference between freshly reconstituted and stored toxin in the early period. When stored toxin was used, atrophic changes in the muscle were less severe than the fresh toxin at 3 months. On nerve evaluation, fresh toxin displays significant acute changes on nerve ultrastructure; however, fresh and stored toxin shows similar degeneration at 12 weeks.

Botulinum neurotoxins: fundamentals for the facial plastic surgeon

The most commonly performed nonsurgical cosmetic procedure in the facial plastic surgery armamentarium involves the various commercial preparations of botulinum neurotoxins. These drugs have undergone a transformation from public health scourge to near ubiquitous therapeutic modality across the entire medical spectrum. Herein, the history of botulinum neurotoxins is reviewed, including an exploration of their pharmacology, neuromuscular junction physiology, a description of the commercially available preparations, and the recent research concerning the practicalities of their clinical use.