The use of botulinum toxin type A to minimize scarring in cleft lip repair: A literature review

Intramuscular versus intradermal botulinum toxin for forehead wrinkles: a review of side effects and efficacy

Botulinum toxin type A (BTA) is a neurotoxin used for both cosmetic and non-cosmetic purposes. BTA is commonly administered as an intramuscular injection to treat wrinkles. However, when it comes to treating forehead wrinkles, intramuscular injection is associated with a greater rate of ptosis. Intradermal injection is currently thought to be a better alternative. We searched PubMed and Google Scholar for research articles published between 1989 and 2023 using the following keywords: "intradermal," "intramuscular," "botulinum toxin," and "forehead wrinkle." The search yielded three randomized controlled trials and a double-blind, split-face case report on 58 patients. We found that although intradermal and intramuscular injections have symmetrical anti-wrinkle effects, the former results in a lower rate of ptosis and a greater degree of pain.

Assessing Adult Patients with Facial Deformities for Injectable Treatment: Do Current Classification Systems and Methodologies Meet Important Patient Needs?

BACKGROUND

Many individuals are affected by facial deformities. Injectable aesthetic treatments can often be used to improve appearance and/or dynamic function. However, to best meet the needs of these patients, broadly applicable methodologies are required for classifying the deformity, assessing severity, and developing a treatment strategy.

OBJECTIVE

To assess whether any published systems could be used for this purpose.

METHODS

Thirty-eight searches were conducted in PubMed (1999-2019; in English). Forty-two publications were identified describing novel classification systems for adult facial deformity. They were analyzed against a checklist of 10 characteristics defining an "optimal" system-based on appropriate anatomical coverage, wide usability across types of deformity, user-friendliness, applicable underlying methodology, and ability to guide treatment with injectables.

RESULTS

None of the systems met more than 7 of the 10 checklist criteria; none were usable across multiple types of deformity or provided a recommendation for treatment with injectables.

CONCLUSION

There remains a need for a broadly applicable system for classifying adult facial deformities ahead of injectable therapy. The checklist provides a developmental framework. With the increasing popularity and accessibility of injectables, this diverse and complex demographic is at risk of mismanagement without superior methods for devising treatment strategies.

Mechanotransduction in skin wound healing and scar formation: Potential therapeutic targets for controlling hypertrophic scarring

Hypertrophic scarring (HTS) is a major source of morbidity after cutaneous injury. Recent studies indicate that mechanical force significantly impacts wound healing and skin regeneration which opens up a new direction to combat scarring. Hence, a thorough understanding of the underlying mechanisms is essential in the development of efficacious scar therapeutics. This review provides an overview of the current understanding of the mechanotransduction signaling pathways in scar formation and some strategies that offload mechanical forces in the wounded region for scar prevention and treatment.

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 botulinum toxin A in unilateral cleft lip scar: comparison of results with different sites of injection

Botulinum toxin type A (BTA) injections into the subjacent orbicularis oris muscle have been shown to improve appearance and produce narrower cheiloplasty scars. This study was performed to determine the effect of BTA injected at different sites on the unilateral cleft lip scar and cleft side nostril width. A double-blind, randomized prospective trial was conducted involving 64 consecutive patients with unilateral cleft lip undergoing primary cheiloplasty between September 2016 and January 2019. The patients were randomized to receive BTA injections either into the subjacent orbicularis oris muscle (4 points group) or into the bilateral nasolabial fold region (6 points group) during cheiloplasty. The scars were assessed by photographic scar width measurements and Vancouver scar scale assessment tool. The cleft side nostril width was compared to the non-cleft side width. Fifty-six patients completed the trial, 24 in the 4 points group and 31 in the 6 points group. There was no significant difference in scar width or nostril width measurements between the groups at the end of follow-up. The Vancouver scar scale assessment was also similar between the groups. There was no significant difference in scar width or nostril width measurements after cleft lip repair between patients treated with botulinum toxin injections to the subjacent orbicularis oris muscle and patients treated with injections in the nasolabial region.

Efficacy and Safety of Botulinum Toxin Type A in Preventing Postoperative Scars and Improving the Cosmetic Appearance of Scars: A Systematic Review and Meta-Analysis

BACKGROUND

Scars with poor cosmesis that develop after wound healing may affect normal life.

OBJECTIVE

To assess the efficacy and safety of botulinum toxin type A (BTXA) in preventing postoperative hypertrophic scars or keloids.

METHODS

A systematic review was performed by searching the PubMed, Cochrane Library, and EMBASE databases from their inception date up to February 2020 for randomized controlled trials (RCTs) evaluating the efficacy of BTXA in preventing hypertrophic scars or keloids. The primary outcome measures included the Vancouver Scar Scale (VSS) score, Visual Analog Scale (VAS) score, scar width, patient satisfaction, and adverse events.

RESULTS

Twelve RCTs involving 497 cases (372 patients) were included. The meta-analysis showed significant differences in the VAS score (weighted mean difference [WMD] = 1.31, 95% CI = 1.06 to 1.55, P < .00001), VSS score (WMD = -1.02, 95% CI = -1.72 to -0.32, P = .004), scar width (WMD = -0.18, 95% CI = -0.29 to -0.08, P = .0008), and patient satisfaction (relative risk = 1.25, 95% CI = 1.06-1.49, P = .01). Four studies reported trivial adverse events.

CONCLUSIONS

This meta-analysis showed that BTXA was more effective than the control treatment in preventing postoperative scars and improving the cosmetic appearance of facial scars for East Asians, and no serious adverse events were found during the follow-up period. However, there was insufficient evidence to support the use of BTXA for the prevention of scars in patients from other ethnic groups and regions or scars in non-facial areas.