Study examines complication rates of toxin injection in masseter

The Journal of Cosmetic Dermatology has published a paper examining the incidence rate of complications from 2,036 treatments of botulinum toxin injections for masseter hypertrophy. From 2011 to 2016, 680 patients received a total of 2,036 sessions of toxin injection for masseter hypertrophy. Their complications or complaints were recorded through follow-up on a by-treatment basis with complications grouped together based on causes. Of the 2,036 sessions, temporary mastication force decrease was reported after 611 (30%), bruising after 51 (2.5%), headaches after 12 (0.58%), smile limitation after 3 (0.15%), paradoxical bulging after 10 (0.49%), sunken cheeks after 9 (0.44%) and sagging after 4 (0.20%). The paper concluded that overall, masseter injections remain very safe but to further decrease the incidence rate and minimise undesirable complications, an understanding of the muscular anatomy is vital. Appropriate dosing, injection location and injection depth are all key factors in achieving the desired result with minimal complications. 

http://onlinelibrary.wiley.com/doi/10.1111/jocd.12473/full