Correction of Malocclusion by Botulinum Neurotoxin Injection into Masticatory Muscles

Abstract

Botulinum toxin (BTX) is a neurotoxin, and its injection in masticatory muscles induces muscle weakness and paralysis. This paralytic effect of BTX induces growth retardation of the maxillofacial bones, changes in dental eruption and occlusion state, and facial asymmetry. Using masticatory muscle paralysis and its effect via BTX, BTX can be used for the correction of malocclusion after orthognathic surgery and mandible fracture. The paralysis of specific masticatory muscles by BTX injection reduces the tensional force to the mandible and prevents relapse and changes in dental occlusion. BTX injection in the anterior belly of digastric and mylohyoid muscle prevents the open-bite and deep bite of dental occlusion and contributes to mandible stability after orthognathic surgery. The effect of BTX injection in masticatory muscles for maxillofacial bone growth and dental occlusion is reviewed in this article. The clinical application of BTX is also discussed for the correction of dental malocclusion and suppression of post-operative relapse after mandibular surgery.Keywords: botulinum neurotoxin; masticatory system; maxillofacial bone; dental occlusion; orthognathic surgery Key contribution: BTX injection into masticatory muscles affects the maxillofacial bony growth and dental occlusion. In clinical practices, BTX injection has been used for reducing post-operative relapse after mandibular surgery.

Botulinum toxin A injection into the anterior belly of the digastric muscle increased the posterior width of the maxillary arch in developing rats

“…In clinical practice, BTX injection into the digastric muscle has been used for the treatment of malocclusion [24]. The patient who has an anterior open-bite after mandible fracture surgery receives BTX into the digastric muscle, and the counter-clock wise rotation of the mandible and stable occlusion can be achieved after treatment [1]. The patient who has BTX injected into the digastric muscle after orthognathic surgery shows more stable occlusion and reduced postoperative relapse [1].…”

“…Botulinum toxin A (BTX) paralyzes the muscle and has been used for therapeutic purposes [1]. In the maxillofacial area, BTX injection is considered a cosmetic therapy and it has been used for the removal of wrinkles or the reduction of muscle volume [2].…”

“…In the maxillofacial area, BTX injection is considered a cosmetic therapy and it has been used for the removal of wrinkles or the reduction of muscle volume [2]. Recently, the indication for BTX injection has become much wider [1, 3]. BTX injection into the maxillofacial area has been used for the treatment of orofacial pain [4], as well as for the prevention of open bite [4] or plate fracture [5].…”

The effect of botulinum toxin-A injection into the masseter muscles on prevention of plate fracture and post-operative relapse in patients receiving orthognathic surgery

“…BTX-A injection into the masticatory muscle in growing rats has shown changes in jaw bone morphology [ 21 ]. Based on these results, BTX-A injection has been used for preventing relapse after orthognathic surgery [ 22 ].…”

Introduction to the Toxins Special Issue on Botulinum Neurotoxins in the Nervous System: Future Challenges for Novel Indications

“…As for novel indications of BoNTs, we should not forget that BoNTs have been considered as agents for inducing controlled paralysis in different muscles of the oral, maxillofacial, and temporomandibular joint region, with the aim to treat dysfunction and dislocation in clinical orthodontics and maxillofacial surgery. Clinical applications of BoNTs in treatment for the correction of severe malocclusion-associated problems, including occlusion after orthognathic surgery and mandible fracture, are reviewed by Seok and Kim [ 18 ]. This particular application of BoNTs is based on the principle that the induction of controlled paralysis of masticatory muscles reduces the tensional force to the mandible and prevents relapse, and affects maxillofacial bone growth and dental occlusion.…”