Cosmetic Treatment Using Botulinum Toxin in the Oral and Maxillofacial Area: A Narrative Review of Aesthetic Techniques January 2023 in “ Toxins ” Sung Ok Hong We don't know much about this study yet. We're maintaining the world's largest resposity of hair loss research. You can help out the community by sending a PDF of this study here . Not sure how to get a study's PDF? You can email the authors of the study. View this study on mdpi.com →