Identicals twins: Assessment and treatment of five pairs with IncobotulinumtoxinA injection in the upper face taking into account the phenotype discordance with the aging process

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Carla de Sanctis Pecora and Karin Ventura

Universidade Estadual de Sao Paulo, Brazil

: J Clin Exp Dermatol Res

Abstract

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Hyperfunctional lines in the skin are caused by repeated contraction of underlying muscles and can develop into wrinkles on the upper face, such as the forehead, glabella, and crow's feet. Previous studies have evaluated the efficacy of botulinum toxin A injection based on standardized protocols, but no prospective study focused on assessing and treating identical twins based on their individual needs. This study aimed to evaluate the presence of hyperfunctional upper facial lines in five pairs of identical twin sisters aged 30 to 40 years, demonstrating the importance of customized injections using the ONE21 technique. The assessment of hyperfunctional upper facial wrinkles involved evaluating the individual anatomy, muscle function and habitual facial movements, including assessing muscles at rest and maximum contraction, mass, and strength. The ONE21 technique was used to determine the distribution of injection points and doses, and two investigators reached a consensus on the assessment before treatment. Standardized pictures were taken before the treatment and on day 30. The findings revealed that although the clinical-anatomical pattern of forehead lines was the same between identical twin pairs, they differed significantly in the number, depth of wrinkles, and facial expression pattern, resulting in distinct points distribution and dosage. Despite having the same genetically determined anatomical pattern, identical twins can present different muscle strength, particular habitual use, and individualized needs, emphasizing the importance of understanding intrinsic and extrinsic factors that contribute to changes in the face over time. The ONE21 technique allowed for an objective and careful assessment of wrinkles on the upper face based on clinical-anatomical features, demonstrating that even identical twins may have different needs and expectations. Therefore, an individualized assessment with a tailored botulinum toxin treatment must be done to achieve superior outcomes and improve patients' satisfaction. This study highlights the uniqueness of every human being, despite having the same genetic makeupn.
Recent Publications:
1) Binder WJ. Long-term effects of botulinum toxin type A (Botox) on facial lines: a comparison in identical twins. Arch Facial Plast Surg. 2006 Nov-Dec;8(6):426-31.
2) Rivkin A, Binder WJ. Long-term effects of onabotulinumtoxinA on facial lines: a 19-year experience of identical twins. Dermatol Surg. 2015 Jan;41 Suppl 1:S64-6
3) Abramo AC, Do Amaral TP, Lessio BP, et al. Anatomy of forehead, glabellar, nasal and orbital muscles, and their correlation with distinctive patterns of skin lines on the upper third of the face: Reviewing concepts. Aesthetic Plast Surg. 2016;40(6):962-71.
4) Moqadam M, Frank K, Handayan C, et al. Understanding the shape of forehead lines. J Drugs Dermatol. 2017;16(5):471- 7.
5) Friedman O. Changes associated with the aging face.h Am. 2005;13(3):371-80.

Biography

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Carla Pecora graduated in Medicine at the Medical Faculty from the Universidade Estadual de São Paulo - USP, Brazil, specialized in Clinical, Surgical and Aesthetic Dermatology in the Universidade Federal de São Paulo - UNIFESP, Brazil, and did a fellowship in clinical dermatology and laser therapy in Hôpital Universitaire de L’Archet, Nice, France. She worked for 14 years in the Cosmiatric Dermatology department of the Universidade Federal de São Paulo, involved in the production of scientific trials and training residents. Dra Pecora is a member of both Sociedade Brasileira de Dermatologia and Sociedade Brasileira de Cirurgia Dermatológica. She runs her own clinic in São Paulo, within 20 years of practice in aesthetic dermatology, including botulinum toxin injection, fillers, biostimulation, threads and lasers. Moreover, she has written some chapters in Dermatology books and published some papers in national and international scientific journals. She presents in national and international conferences and is a consultant and member in advisory boards for aesthetic dermatology including fillers and botulinum toxin.