Application of botulinum toxin in maxillofacial field: Part III. Ancillary treatment for maxillofacial surgery and summary

New advances in the treatment of thin endometrium

Thin endometrium (TE) is defined as a mid-luteal endometrial thickness ≤7mm. TE can affect endometrial tolerance, leading to lower embryo implantation rates and clinical pregnancy rates, and is also associated with impaired outcomes from assisted reproductive treatment. Herein, we systematically review TE causes, mechanisms, and treatments. TE pathogenesis has multiple causes, with the endometrium becoming thinner with age under hormonal influence. In addition, uterine cavity factors are important, as the inflammatory environment may affect expressions of certain genes thereby inhibiting endometrial stromal cell proliferation and promoting apoptosis. Long-term oral contraceptive use or the use of ovulation-promoting drugs are also definite factors contributing to endometrial thinning. Other patients have primary factors, for which the clinical etiology remains unknown. The main therapeutic strategies available for TE are pharmacological (including hormonal and vasoactive drugs), regenerative medicine, intrauterine infusion of growth factor-granulocyte colony-stimulating factor, autologous platelet-rich plasma, and complementary alternative therapies (including traditional Chinese herbal medicine and acupuncture). However, the associated mechanisms of action are currently unclear. Clinical scholars have proposed various approaches to improve treatment outcomes in patients with TE, and are exploring the principles of efficacy, offering potentials for novel treatments. It is hoped that this will improve TE tolerance, increase embryo implantation rates, and help more couples with infertility with effective treatments.

Optimizing drug regimens and supplementation in orthognathic surgery: A comprehensive and practical guide

OBJECTIVE

This study aimed to comprehensively review the literature and provide a practical guide for optimizing drug regimens and supplementation related to orthognathic surgery.

METHODS

The authors conducted a thorough review of the existing literature, following the PRISMA-ScR guidelines. Various types of studies except case reports and reviews were included. The study applied specific inclusion criteria, focusing on perioperative and/or postoperative drugs, medications, or supplementation related to orthognathic surgery.

RESULTS

This guide included 78 studies on various medications in orthognathic surgery. It encompasses clinical trials, cohort studies, cross-sectional studies, prospective and retrospective studies. The topics covered include antibiotics, analgesics, corticosteroids, antiemetics, hemostatic agents, local anesthetics, herbal medicine, and botulinum toxin. Pain and edema control involved specific medications, while local anesthesia utilized ropivacaine and bupivacaine. The guide also discusses mineral and vitamin supplementation. The effectiveness of hemostatic agents and antiemetics was highlighted.

CONCLUSION

Pain management, reduced swelling, enhanced wound healing, and faster recovery are among the advantages. In addition to the standard drugs and medications, the inclusion of vitamin and mineral supplements, tranexamic acid, postoperative anesthetic blocks, and preemptive antiemetics is anticipated to offer various benefits in orthognathic surgery, despite the limited available evidence.

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.

Intrauterine botulinum toxin A administration promotes endometrial regeneration mediated by IGFBP3-dependent OPN proteolytic cleavage in thin endometrium

Adequate endometrial growth is a critical factor for successful embryo implantation and pregnancy maintenance. We previously reported the efficacy of intrauterine administration of botulinum toxin A (BoTA) in improving the endometrial angiogenesis and the rates of embryo implantation. Here, we further evaluated its potent therapeutic effects on the uterine structural and functional repair and elucidated underlying molecular regulatory mechanisms. This study demonstrated that a murine model of thin endometrium was successfully established by displaying dramatically decreased endometrial thickness and the rates of embryo implantation compared to normal endometrium. Interestingly, the expressions of insulin-like growth factor binding protein-3 (IGFBP3) and an active 35 kDa-form of osteopontin (OPN) were significantly reduced in thin endometrium, which were almost fully restored by intrauterine BoTA administration. Neutralization of BoTA-induced IGFBP3 subsequently suppressed proteolytic cleavage of OPN, exhibiting un-recovered endometrial thickness even in the presence of BoTA administration, suggesting that BoTA-induced endometrial regeneration might be mediated by IGFBP3-dependent OPN proteolytic cleavage. Our findings suggest that intrauterine BoTA administration improves the endometrial environment in our murine model with thin endometrium by increasing endometrial receptivity and angiogenesis in a manner dependent on the regulatory effect of IGFBP3 on OPN proteolytic cleavage, proposing BoTA as an efficient therapeutic strategy for the patients with thin endometrium.

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.

Surgical Versus Nonsurgical Lower Face Contouring: Layperson Perceptions of Attractiveness and Personality Traits

BACKGROUND

Traditional approaches to lower face contouring involve ostectomy of the mandibular angle or body. More recently, nonsurgical techniques have gained popularity, including neurotoxin injection to the masseter muscle. This study aims to evaluate layperson perceptions of patient attractiveness and personality traits following lower face contouring using either surgical or nonsurgical treatment.

METHODS

In this survey study distributed via Amazon's Mechanical Turk, respondents viewed a series of 14 patient images obtained in clinic before and after surgical or nonsurgical jawline slimming, or without any facial aesthetic procedure. Respondents rated changes in attractiveness and personality trait scores between the before and after image (score: -50 to 50, with 50 representing the greatest posttreatment increase and 0 representing no change). We used descriptive statistics and multivariable regression to determine differences in respondent ratings between patient images.

RESULTS

A total of 415 respondents (mean age 38 years, 50.6% female) successfully completed the survey. Compared to patients who underwent nonsurgical treatment, those who received surgery had significantly greater increases in perceived attractiveness (P < 0.001), femininity (P < 0.001), friendliness (P < 0.001), intelligence (P < 0.001), trustworthiness (P < 0.001), financial wealthiness (P < 0.001), dominance (P < 0.01), and self-esteem (P < 0.001). Gonial angles increased and jaw widths decreased following both surgical and nonsurgical intervention, with no statistically significant difference between treatment groups.

CONCLUSIONS

From the layperson perspective, surgical compared to nonsurgical jawline contouring offers greater improvements in perceptions of attractiveness and favorable personality traits.

Non-invasive Intrauterine Administration of Botulinum Toxin A Enhances Endometrial Angiogenesis and Improves the Rates of Embryo Implantation

Endometrial angiogenesis plays crucial roles in determining the endometrial receptivity. Defects in endometrial receptivity often cause repeated implantation failure, which is one of the major unmet needs for infertility and contributes a major barrier to the assisted reproductive technology. Despite the numerous extensive research work, there are currently no effective evidence-based treatments to prevent or cure this condition. As a non-invasive treatment strategy, botulinum toxin A (BoTA) was administered into one side of mouse uterine horns, and saline was infused into the other side of horns for the control. Impact of BoTA was assessed in the endometrium at 3 or 8 days after infusion. We demonstrated that BoTA administration enhances the capacity of endothelial cell tube formation and sprouting. The intrauterine BoTA administration significantly induced endometrial angiogenesis displaying increased numbers of vessel formation and expression levels of related marker genes. Moreover, BoTA intrauterine application promoted the endometrial receptivity, and the rates of embryo implantation were improved with BoTA treatment with no morphologically retarded embryos. Intrauterine BoTA treatment has a beneficial effect on vascular reconstruction of functional endometrium prior to embryo implantation by increasing endometrial blood flow near the uterine cavity suggesting BoTA treatment as a potential therapeutic strategy for patients who are suffering from repeated implantation failure with the problems with endometrial receptivity.

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.