Botulinum Toxin Injections for Masseter Reduction in East Asians

Abstract

BACKGROUND Cultural ideals for a slimmer face have led to an upsurge in interest in facial contouring among East Asians. Although surgical resection has traditionally been the main treatment option, botulinum toxin injection is becoming a popular, noninvasive alternative. OBJECTIVE To describe the use of botulinum toxin injection for masseter reduction in East Asians. METHODS An electronic search of the PubMed database was performed for studies published from 2000 to 2017 that meet the word combination of botulinum toxin, masseter, hypertrophy, and/or lower face contouring. Only the studies conducted in East Asian countries were analyzed in this review, exception of one study from Thailand. RESULTS A total of 12 publications were identified. Each study was reviewed to extract relevant information on patient selection, injection techniques, efficacy, dosage, frequency, and main side effects of treating masseters with botulinum toxin. CONCLUSION Botulinum toxin injection for masseter reduction in East Asians is efficacious and generally considered safe with no significant side effects. Future areas for investigation include defining the criteria for benign masseteric hypertrophy, minimum effective dosage of botulinum toxin, and the potential long-term effects of the injection.

Pivotal role of injection volume on sunken cheek prevention in masseter muscle BoNT‐A injection: A cadaver study

“…Usually 100 units of BoNT‐A was diluted with 2 or 2.5 ml of saline to obtain a concentration of 50 or 40 U/ml, and 40–60 U and 0.8–1.5 ml of BoNT‐A was injected into either side of the masseter muscle 11,17–20 . Despite various multi‐point injection methods are commonly performed, 1 there are physicians who still prefer single‐point injection, 21 and some claim that there is no difference between the effects of single‐point injection and multi‐point injection 22 . In this cadaver study, we found that the upward ICG spread in 94.4% of masseters that injected with 1 ml of ICG exceeded the mouth corner‐tragus line.…”

Deep Lateral and Endoscopic Inferomedial Orbital Decompression Combined with Injection of BTA for Extraocular Muscles in A Patient with TAO

“…Botulinum toxin A (BTA) injection has been considered as a favorable procedure in treating benign masseteric hypertrophy because of its effective reduction of the volume of masseter muscle and with no significant side effects [6]. In fact, BTA injection in the extraocular muscles has also been suggested to provide temporary relief of diplopia in selected patients during the active phase of TAO.…”

Comparison between Conventional Blind Injections and Ultrasound-Guided Injections of Botulinum Toxin Type A into the Masseter: A Clinical Trial

“…Botulinum toxin type A (BoNT-A) was first used for weakening the eye muscles, and its application was expanded by Moore and Wood in 1994 as a treatment for masseter hypertrophy [ 1 , 2 , 3 ]. The demand for BoNT-A injections into the masseter muscle is increasing markedly, especially among some Asian populations in which it is assumed that the ovoid facial shape and slim lower face is optimal [ 3 , 4 , 5 ]. These injections are used not only for aesthetic purposes to reduce masseter hypertrophy, but also for therapeutic purposes to reduce bruxism and clenching [ 4 , 6 ].…”