[Facial anatomy and botulinum toxin: the muscular balances]

[Forehead injections: Anatomy, technics, products]

Knowledge of anatomy not only allows optimal treatment and therefore full satisfaction of our patients, but is also fundamental in the prevention of complications. A thorough understanding of aging allows for effective treatments, as most patients demand a natural result, removing the inevitable signs of aging, which can only be understood by considering their aging. Facial aging is a natural but complex multifactorial process, particularly for the forehead. In this article, we will focus on botulinum toxin as well as fillers in aging.

The One21 Technique: An Individualized Treatment for Glabellar Lines Based on Clinical and Anatomical Landmarks

PURPOSE

Botulinum toxin type A is an effective treatment for glabellar dynamic wrinkles. As the muscular group involved in the contraction of the glabella varies among people, individualized treatment can achieve optimal results. This study evaluates a customized assessment for the treatment of glabellar lines with Incobotulinumtoxin-A, leading to an individualized points distribution and dosage.

PATIENTS AND METHODS

A single-center, evaluator-blinded, therapeutic cohort study enrolled 130 women with moderate or severe glabellar wrinkles. They underwent Incobotulinumtoxin-A injection following the standard 5-point injection at the glabellar muscles (n = 65) or an individualized assessment and scheme treatment based on anatomical references of contraction, the One21 technique (n = 65). All the patients were photographed under maximum contraction before treatment (T0) and after 4 weeks (T28). The photos were randomly assessed by two blinded, experienced raters to consensually grade the severity according to the Merz Aesthetics Scales (MAS). The primary clinical efficacy was defined as a 2-point reduction in the MAS score, on Day 28.

RESULTS

The groups were homogeneous regarding age, phototype, and baseline MAS scores. On Day 28 (T28), 64 (98.5%) patients from the One21 group and 52 (80%) from the 5-point group reduced the MAS score by at least two points (p < 0.01). When adjusted by age and phototype, both groups reduced the MAS score at T28 (p < 0.01); nevertheless, patients from the One21 group significantly performed better (p < 0.01), with a much higher rate response rate at T28, in comparison to the 5-point group. Of patients enrolled in the 5-point group, 83.1% utilized muscle groups other than the procerus and corrugator in glabellar wrinkle formation, and 17 (24.6%) presented asymmetrical contraction. Patients from the 5-point group with glabellar asymmetry and those who utilized the frontalis and orbicularis presented inferior performance (p < 0.05), reinforcing the importance of an individualized assessment and treatment plan.

CONCLUSION

The One21 technique yielded better results than the standard 5-point treatment in reducing glabellar dynamic lines with Incobotulinumtoxin-A, especially for asymmetric lines of the glabella or the involvement of muscle groups other than the procerus and corrugator.