A Simple Botulinum Toxin Injection Technique for Masseter Reduction Zhi Yang Ng, MBChB, MRCS and Tiffiny Yang, MBBS, GDFM Author information Copyright and License information Disclaimer The off-label use of Botulinum toxin for masseteric hypertrophy is well-established in the Eastern Asian population and of growing interest in the West.


A Simple Botulinum Toxin Injection Technique for Masseter Muscle Reduction Zhi Yang Ng, MBChB, MRCS and Tiffiny Yang, MBBS, GDFM Author information Copyright and License information Disclaimer. The off-label use of botulinum toxin for masseteric hypertrophy is well established in the East Asian population and of increasing interest in the West. Many variations in injection techniques have been described, 5 reported so far. Not surprisingly, according to a recent literature review of more than 4,000 such cases from 1994 to 2018, a host of complications can develop. These include pain at the injection site which is the most common, followed by localized swelling, bruising, headache, weakness and pain in chewing, as well as the development of an asymmetrical smile. Recently, researchers have also looked at ultrasound-guided injections of botulinum toxin, which has an advantage over the "conventional" blind technique. Here, we would like to share a simple masseter muscle reduction injection technique with botulinum toxin that has been used by the senior author (T.Y.) since 2010 and successfully used by a more experienced practitioner (Z.Y.N.) during the period of October 2019 to July 2020. in 55 patients there was only 1 case of inadequate treatment response. Before entering the treatment room, the anesthetic cream is applied for approximately 30 minutes bilaterally in the lower massage area, near the angle of the mandible. Patients are then asked to clench and hold their teeth to enable the anterior border (Line A) and the most pronounced bulge (X) of the masseter to be marked (Figure 1); they are allowed to rest after. Depending on the individual anatomy, a second line is then drawn from the tragus (Line B) or from the inferior border of the earlobe (Line B') to the corner of the mouth, with the aim of capturing most of the mass . within these 2 lines (Figure 1) to minimize the risk of diffusion into the zygomaticus complex. Cooling of the skin with a cold pack is then applied to the most prominent point, followed by perpendicular injection with a 30G needle in a 1 cc syringe until the mandible is felt. At this point, the needle is withdrawn slightly and a third of the Botulinum toxin is deposited. The needle is then reoriented without withdrawing from the skin and advanced slightly for the next 2 deposits, usually anterior and superior; this is then repeated for the other side. The total time taken for actual injections (×2 total) is usually less than 1 minute. After the procedure, there may be spotting, but this resolves almost immediately with light pressure. Pain and bruising are rare, and occasionally some patients report mild discomfort, but otherwise this is self-limiting and resolves within a few days. In our experience, patients with bilateral benign masseteric hypertrophy can be safely treated with this simple technique (Figure 2). Our preference is to use Dysport (Ipsen, Wrexham, UK), but Botox (Allergan plc, Dublin, Ireland) can be similarly administered, depending on patient preference and budget. Repeated procedures are performed, usually at the request of the patient at 4-6-month intervals. We hope to have demystified the treatment of masseteric hypertrophy with botulinum toxins and believe that ours is a simple, fast and safe technique with an overall, very high level of patient satisfaction. Go to Simple Botulinum Toxin Injection Technique