The width of the lower third of the face is mainly determined by the size and shape of the jawbone, the thickness of the masseter muscle and the volume of adjacent subcutaneous tissue. The ideal, culturally recognized pattern for a male face corresponds to a wider lower third and a mandibular angle tending to 90º, while a female face should have a more oval appearance or the shape of a heart, and the middle third wider than the lower third. In order to achieve these aesthetically ideal proportions, botulinum toxin type A (BoNTA) has been successfully applied in the masseter muscle, which is one of the determinates of the lower face's width. Te present article reviews the current literature on the use of botulinum toxin for this purpose, offering the experience of the authors in this practice, aiming at achieving a more harmonious facial contour.

Keywords: BOTULINUM TOXINS, TYPE A; MASSETER MUSCLE; HYPERTROPHY

Introduction: The use of botulinum toxin in the periorbital muscles is aimed at reducing expression lines in that site, correcting the eyebrows' height and treating blepharospasm. However, the application of botulinum toxin in this area can lead to undesirable side effects, such as ptosis, edema in the lower eyelids, artificial appearance of the demarcation area between the orbicularis muscle's treated area and the malar region, ectropion and hematomas.
Objective: To treat the dynamic wrinkles in the lower portion of the orbicularis oculi muscle through injections of microdoses of botulinum toxin.
Methods: A prospective monocentric study with the analytical longitudinal observation of 300 patients undergoing treatment with botulinum toxin microdoses in the lower eyelids' rhytids was carried out. Sociodemographic data, patient satisfaction, dose quantification and complications were analyzed.
Results: Sixty-six percent of the patients showed a total improvement of the wrinkles after the first session. The other required an additional session. Eighty-six percent preferred the treatment with this therapeutic modality.
Conclusions: Despite the great benefit offered by the classic injection points for the treatment of periorbital rhytids types I to III, the authors observed the need to treat rhytids type B (presence of wrinkles on the lower eyelid). Due to the high rate of complications in this region, microdoses of botulinum toxin were proven to be effective and safe.

Keywords: BOTULINUM TOXINS, TYPE A; ESTHETICS; DERMATOLOGY

Introduction: The application of botulinum toxin in the perioral region is a minimally invasive procedure that leads to substantial improvement in the signs of aging in addition to increasing the volume of the lips. However literature on this procedure is still scarce.
Objective: To evaluate changes in shape and volume of the lips, as well as the patients' satisfaction after the application of botulinum toxin in perioral lines.
Methods: Nineteen patients underwent evaluation, photographic record and measurements following the application of botulinum toxin in the perioral region, being subsequently assessed for changes in the lips and satisfaction.
Results: Most of the patients rated their lips as moderately or significantly more attractive after the application of botulinum toxin (p = 0.039). Fifteen women deemed the changes in the lips as a major factor in the overall improvement of their faces.
Conclusions: The use of botulinum toxin in the perioral region leads to the elevation of the upper lip, causing the shortening of the philtrum and the extension of the vermilion. The application of botulinum toxin in the vermilion's border leads to the relaxation of the orbicularis muscle, favoring a more intense tonus effect arising from the upper lip lifting muscles. The patients' satisfaction with the appearance of their lips was evaluated by four additional questions (linked to the lip's shape, volume, attraction and beauty), receiving positive answers. Side effects were minimal.

Keywords: LIP; BOTULINUM TOXINS, TYPE A; BOTULINUM TOXINS

Introduction: Standard dilution of botulinum toxin is performed with 0.9% saline solution. Some studies show that when diluted in lidocaine and epinephrine, the toxin preserves its function without compromising effectiveness or safety.
Objective: To establish whether the paralyzing effect of ona-toxin type A reconstituted in anesthetic (2% lidocaine) and vasoconstrictor agent (1: 50,000 epinephrine) is as effective as that of the same toxin reconstituted in saline solution, at 48 hours, 1 week, 2, 4, 12 and 24 weeks, for the treatment of periocular lines. To compare the tolerance to pain between the two reconstitution alternatives.
Methods: Fifteen patients with periocular wrinkles were randomized to receive onabotulinum toxin diluted in lidocaine with epinephrine or in saline. Re-evaluations were carried out in 48 hours, 1 week, 2, 4, 12 and 24 weeks.
Results: The data indicate that there was no difference in the symmetry and durability of the botulinum toxin, nor in the pain during the application.
Conclusions: There was no statistically significant difference in the frequency of lateral periocular muscle paralysis and symmetry resulting from the applications of onabotulinum toxin reconstituted in lidocaine with epinephrine or in saline solution. This outcome is consistent with those of previous studies.

Keywords: BOTULINUM TOXINS, TYPE A; DILUTION; LIDOCAINE

Scalp folliculitis is a common condition in dermatological practice and a diagnostic and therapeutic challenge. The authors describe a case of chronic suppurative folliculitis in a 53-year-old man who had bore the condition for 18 years. The control of chronic staphylococcal infection with sulfamethoxazole-trimethoprim for 7 months, with progressive shaving of keloid lesions (5 sessions) and application of 90% trichloroacetic acid on wounds up until re-epithelialization (7 months), were successful in treating the disease.

Keywords: Folliculitis; Staphylococcus aureus; Trichloroacetic acid

INTRODUCTION: Acne vulgaris is an inflammatory disorder of the pilosebaceous gland. Palmitic acid is one of the major types of free fatty acid and may play a role in acne pathogenesis. In addition, recent studies suggested that Staphylococcus epidermidis might be involved in acne.
OBJECTIVE: To explore the association between Staphylococcus epidermidis and palmitic acid in acne vulgaris.
METHODS: Forty-three high school students at an urban area in South Sulawesi, Indonesia, were included. The palmitic acid level was measured using gas chromatography and comedone was cultured to detect the microbiota profile. Mann-Whitney test was used to analyze the median palmitic level diference between groups with different acne vulgaris severity.
RESULTS: Fourteen patients (32.6%) had mild acne vulgaris, while 14 and 15 patients had moderate and severe acne vulgaris, respectively The severe and moderate group showed significantly higher palmitic acid level compared with the mild group. Subgroup analysis of patients with moderate and severe acne vulgaris positive for S. epidermidis showed a significantly higher palmitic acid level compared with the mild group.
CONCLUSIONS: This result suggests that S. epidermidis may be associated with the palmitic acid level and may contribute to acne pathogenesis.

Keywords: Acne vulgaris; Staphylococcus epidermidis; Palmitic acid

INTRODUCTION: Raynaud's phenomenon (RP) is an exaggerated physiological response of the extremity vessels, mainly to cold and stress. Patients refractory to clinical treatment or intolerant to its adverse events may be treated with local injection of botulinum toxin (BTX).
OBJECTIVE: To describe the experience of botulinum toxin use in severe cases of RP.
METHODS: Observational, descriptive, retrospective, and unicenter study of case series of severe RP treated with BTX-A, from 2011 to 2015. Parameters of pain, numbness, color, and stiffness were scored by visual analogical scale (VAS) and tabulated and compared before and after the treatment.
RESULTS: Total pain improvement in 71.4% of cases and partial improvement in 28.6%. Numbness disappeared in 57.1% of cases and improvement in 42.9%. There was a total regression of stiffness in 57.1% of cases and partial improvement in 28.6%. The color was completely reversed in 57.1% of the patients. There was ulceration healing in the only case in with they were present. Ischemic attacks were reduced in 85,7% of cases. No complications occurred.
CONCLUSIONS: This study suggests that the use of BTX-A in patients with severe RP is a promising therapeutic option.

Keywords: Raynaud disease; Botulinum toxins; Botulinum toxins, type A

INTRODUCTION: Patients often request anti-aging treatments of the perioral and periorbital regions. Most of the time, it is necessary to use a combination of procedures, so the result meets the patient’s expectations.
OBJECTIVE: This is a prospective, single-center, and comparative study assessing the rejuvenation of the perioral and periorbital regions after treatment with medium depth chemical peel using phenol 88% with or without the previous application of botulinum toxin.
METHODS: Sixteen patients underwent regional peel with phenol 88%; eight received botulinum toxin application two weeks before. The assessment was conducted using standard photographs and evaluation scales by doctors and patients.
RESULTS: The overall evaluation by doctors and patients on the 45th day was considered excellent or good for all patients, with little advantage for combined treatment in the periorbital region.
CONCLUSION: Combining these two relatively low-cost procedures, often overlooked by dermatologists, resulted in a significant improvement in the changes related to aging in these areas.

Keywords: Botulinum toxins type A; Chemexfoliation; Phenol; Rejuvenation

INTRODUCTION: Facial erythema is a frequent and often distressing complaint in patients with rosacea. Botulinum toxin has been proposed as a treatment of facial erythema with relatively good results.
OBJECTIVE: This study aims to assess botulinum toxin’s safety and efficacy in a split-face trial in two different administration modalities: intradermal injections on one side of the face and facial electroporation on the other side.
MATERIALS AND METHODS: The trial enrolled 20 subjects aged between 25 and 75 years with erythematotelangiectatic rosacea. Subjects received five units of Botulinum toxin through intradermal injections on the right side of the face. The same amount was introduced through electroporation technique on the left side. We conducted the evaluation using a standardized erythema grading system (System Vectra) and digital photographs at baseline, 2, 6, and 12 weeks.
RESULTS: The effectiveness in reducing the erythema of botulinum toxin with both the injection and electroporation was evident from the second week and persisted until week 12. Both techniques were effective.
CONCLUSIONS: Intradermal injection of botulinum toxin and electroporation seems both effective and safe for treating erythema related to rosacea. The mechanism of action is still controversial.

Keywords: Erythema; Mesotherapy; Botulinum Toxins, Type A

INTRODUCTION: Hidradenitis suppurativa (HS) is an inflamatory, chronic, recurrent, and debilitating condition. There is a lack of consensus about its treatment.
OBJECTIVE: We conducted a review of the national and international literature, searching for articles that addressed the use of botulinum toxin in HS, in addition to describing the doses and techniques used.
METHODS: A bibliographic search was performed in LILACS, Medline, and SciELO.
RESULTS: Botulinum toxin can be an effective therapy in patients with HS, especially in cases of concomitant hyperhidrosis and traditional therapies fail. It offers the possibility of conducting treatment with minimal adverse events, reproducible over time without loss of effectiveness, in addition to reducing pain.
CONCLUSIONS: Patients will likely need more than one treatment over time, as the lesions tend to recur after 6 to 10 months. The technique used has been the standard for hyperhidrosis. Further research is needed to understand its role in the management of HS, including the ideal dosage and frequency of administration.

Keywords: Hidradenitis suppurativa; Hidradenitis; Botulinum toxins; Botulinum toxins, type A

Frontal fibrous alopecia is a primary lymphocytic scarring alopecia that is difficult to control, with a perifollicular lichenoid infiltrate marking its histology. Since its description in 1994 by Kossard, there has been an increase in cases reported worldwide. This article reports two cases that underwent incisional biopsies with longitudinal and transverse sections in areas presenting higher disease activity and reviews some aspects of this dermatosis. It also addresses the suspicion of a possible relationship with the application of botulinum toxin – a question already raised by other authors but with no established confirmation.

Keywords: Alopecia; Botulinum toxins; Botulinum toxins type A

BACKGROUND: The SARS-CoV-2 infection has spread worldwide rapidly since its identification at the end of 2019. Globally, until April 2021, there have been more than 150 million confirmed cases of Covid-19, including over 3 million deaths. Therefore, a race was promptly started to produce an effective vaccine against the new virus. Botulinum toxin injection remains the leading non-surgical cosmetic procedure worldwide, with a high rate of efficacy and patient satisfaction.
AIMS: This study aims to analyze the association between the SARS-CoV-2 vaccine and the immediate botulinum toxin response.
MATERIALS AND METHODS: This was an observational, retrospective, and multicenter study. Data were collected between April and June 2021, and a medical record review of 71 patients from 27 to 76 years old treated with botulinum toxin injection.
RESULTS AND CONCLUSION: There were no meaningful changes in the immediate outcome of patients vaccinated for Covid-19 and botulinum toxin. However, it is vital to underline that follow-up and further studies are needed to define whether the Covid-19 vaccine can alter the duration of effect and efficiency of the botulinum toxin.

Keywords: Covid-19; Botulinum toxins type A; Vaccination

Notalgia Paresthetica (NP) is a sensory neuropathy characterized by itching, with or without a macule. The Botulinum Toxin A treatment may have beneficial effects on pruritus, possibly by inhibiting the substance P. This study aims to evaluate the benefits/limitations of Botulinum Toxin in NP treatment. The methodology consisted of the selection of publications in PubMed, filtered by predefined criteria. Five articles were compiled, and the results were favorable in four of them. The study concluded the effectiveness of Botulinum Toxin A treatment in most of the articles, especially in the pruritus improvement.

Keywords: Pruritus; Botulinum toxins type A; Hyperesthesia; Hyperpigmentation.

Syringomas are benign adnexal neoplasms that develop from eccrine sweat ducts. They are mostly found in early adulthood, with a female gender predominance. They typically occur on the face, particularly the periorbital region, which has a high demand for cosmetic enhancement. Management of periorbital syringomas is challenging, with no consistently effective treatment available. Intradermal injection of botulinum toxin A (BTX-A) is a new treatment modality for periorbital syringoma. We present a 53-year-old female patient with periorbital syringoma who was successfully treated with intradermal BTX-A monotherapy as a painless, cost-effective treatment that produced better long-term results than carbon dioxide laser.

Keywords: Botulinum Toxins, Type A; Syringoma; Carbon Dioxide

A patient with dissecting folliculitis of the scalp who did not respond to antibiotic therapy received four monthly sessions of intradermal administration of 100 IU of botulinum toxin A. Four months after treatment, a complete recovery of the affected area of the patient's scalp was observed. A biopsy taken from the affected area showed the presence of Staphylococcus lugdunensis and Staphylococcus aureus resistant to erythromycin. Botulinum toxin A had no effect on the viability or biofilm production of the Staphylococcus strains, indicating that the healing effect of the toxin was associated with the host response alone.

Keywords: Botulinum Toxins Type A; Folliculitis; Alopecia; Staphylococcus aureus; Staphylococcus lugdunensis.