Botulinum Toxin Literature Review

The compilation of data in this review led to the fact that the use of Botox in TMJ Disorders is beneficial and has little or no side effects. This study made use of targeted and identified well-designed clinical trials in which investigators tested the usage of Botox on subjects directly using modern technology and equipment.
Botulinum toxin exerts its effect by cleaving key proteins required for nerve activation. First, the toxin binds specifically to nerves which use the neurotransmitter acetylcholine. Once bound to the nerve terminal, the neuron takes up the toxin into a vescicle. As the vesicle moves farther into the cell, it acidifies, activating a portion of the toxin which triggers it to push across the vesicle membrane and into the
Freund et al in 2013[8] reported on 46 patients with Temporomandibular disorders treated with 150 units of BoTN-A to the masseter and temporalis muscles. They found significant reductions in their subjective and objective pain scores, and all patients with restricted mouth opening had varying degrees of improved range of motion. They also reported successful treatment of various conditions that fall under the general category of TMD such as bruxism and clenching, oromandibular dystonias, trismus, masseter and temporalis hypertrophy, and headaches. In an open-label study of roughly 100 patients with TMD they found a 70% response rate to BoTN-A injections to the masseter, temporalis and lateral pterygoid muscles. Response was defined as a 50% or greater reduction of subjective pain and/or frequency of pain. In a multicenter randomized double-blind, placebo controlled fixed dose study (50 units Botox to each masseter muscle and 25 units Botox to each temporalis muscle), reduction of subjective pain and tenderness to palpation was greatest at 8 weeks following injections. The authors of this study also noted a decrease in the average daily use of pain medication over the 16 week duration of this
The study enrolled seven patients with a total of 11 joints; all patients were stage I or II of Wilke's staging for internal derangement. BOTN-A was injected in the ipsilateral LP muscle with electromyogram (EMG) guidance and the subjects were assessed for 4 months. Maximum inter-incisal opening, range of lateral movement, and the presence of a click were recorded throughout the follow-up period, and magnetic resonance imaging (MRI) was ordered at the end of the 4 months. The results showed that the decrease in inter-incisal opening and side to side movement immediately postoperative was statistically significant, while the difference by the end of the follow-up period was insignificant. MRI showed a marked improvement in disc position postoperatively. It may be concluded that BOTN injection in the LP muscle leads to the disappearance of joint clicking clinically and a significant improvement in disc position as shown on