RESUMO
BACKGROUND: There is no consensus in the literature about the ideal technique for precisely placing botulinum toxin in the frontal facial regions for the most natural posttreatment appearance. OBJECTIVES: The authors describe a safe and effective dosage template for botulinum toxin injection (a "dose disc," which makes it possible to estimate the approximate area to which the action of the toxin dose will reach, thereby guiding the positioning of the injection in a very practical way) for frontal wrinkle effacement, preserving residual movement whenever possible. METHODS: Fifty adult patients who presented to the authors' private clinic between January 2009 and May 2010 with aesthetic concerns about cutaneous expression wrinkles in the frontal region of their faces were selected for this study. Patients were sequentially divided into two groups: Group 1 included the first 15 patients, who underwent injections in the frontal region on the first visit and glabellar injections 15 days later; Group 2 included the subsequent 35 patients, who underwent frontal and glabellar treatment simultaneously. All pretreatment markings in both groups were made with the authors' "dose disc, which allows for overlap of the "halos" of effect. RESULTS: In the 50 patients included in the study, 317 injections were performed with the dose disc. Two treatment failures occurred (etiology unknown), and five patients presented with failure due to irregular technical positioning of the discs. The latter patients were treated at the beginning of the study and exhibited residual wrinkles. Only one case of complete toxin inactivity was observed. All patients with treatment failures underwent successful correction with additional injections. There was no evidence of palpebral ptosis, eyebrow ptosis, or any other serious diffusion or positioning side effects. CONCLUSIONS: A fixed dose disc template can be a useful tool for botulinum toxin injections in the frontal region of the face. Future studies assessing other disc models for different doses and different injection methods are needed, with the goal of establishing a longer duration of the effect and devising similar templates for other facial areas.