The effects of botulinum toxin A injection on the lateral pterygoid muscle in patients with a painful temporomandibular joint click: a randomized clinical trial study

Abstract

Background Temporomandibular disorder (TMD) is the main cause of non-dental pain in orofacial area. The most common symptoms of TMD are joint pain, joint sound and limitation of jaw function. Botulinum toxin (BTX) injection is considered a potential treatment for TMD due to its pain-relieving properties and its ability to reduce muscle activity. Most of the studies are case series and further investigations are required to prove the efficacy of this treatment modality. Thus, in this study, we aimed to investigate the effect of BTX-A injection on the lateral pterygoid (LP) muscle and to evaluate its efficacy regarding TMD. Materials and methods Thirty-eight patients (19 women and 19 men; mean age of 26.53 years) with painful unilateral temporomandibular joint click and LP muscle tenderness were enrolled in this study. They were divided into two groups; one received an extraoral BTX-A injection in the LP muscle, and the other received a placebo injection. Pain severity, jaw movements, click severity, and Helkimo index were recorded at the first visit, as well as one week, one month, and three months after the intervention. Data were analyzed using repeated-measures analysis of variance and t-tests. Results The results showed that click severity was not significantly different between the BTX-A and placebo groups (P = 0.07). Pain and Helkimo index decreased significantly in the BTX group (P = 0.00 and P = 0.006, respectively); however, there was no significant difference between the two groups (P = 0.22 and P = 1, respectively). There was a significant difference in lateral movements between the groups (P = 0.00) but not in protrusive movement (P = 0.095). Conclusions It can be concluded that although some studies have stated that BTX injection can make the click sound disappear, in this study, we did not find a significant difference between the two groups. Furthermore, our results showed that click and pain severity decreased, but the difference was not statistically significant. Therefore, further studies with a higher dosage of BTX and more participants are recommended. Trial registration The local Ethics Committee of Shiraz University of Medical Sciences approved this research (IR.SUMS.REC. 01/10/2018 and IRCT20130521013406N3).

Preliminary Findings of the Efficacy of Botulinum Toxin in Temporomandibular Disorders: Uncontrolled Pilot Study

“…These results would agree with those obtained by Bakke et al [ 57 ], who, by BTX-A injections into the lateral pterygoid muscle, temporarily reduced the muscle action, but the clicking was permanently eliminated and did not reappear during the 1-year observation period, obtaining a small but clear positional improvement in the disc–condyle relationship. Similarly, other studies [ 58 , 59 , 60 ] with BTX-A injections into the lateral pterygoid muscle reported benefits on temporomandibular clicking.…”

Velopharyngeal Insufficiency After Botox Injection for Persistent Bruxism

“…An extraoral preauricular in-plane approach with ultrasound guidance can minimize the risk of complications 4,9 . Lower injection volume and dose are essential to reduce the risk of hemorrhage and complications due to proximity to vital structures when injecting BTX into the LP muscle 10 . Patients should receive proper medication and follow instructions, such as chewing bilaterally, eating soft foods, and using warm packs to alleviate symptoms.…”

Clinical and cone-beam CT analysis of the effectiveness of anterior repositioning splint therapy in the management of temporomandibular joint click in different age groups

“…Joint click is mainly caused by DDWR and is a typical symptom for TMD [4]. ARS therapy is considered one of the most effective therapies for treating disc-displacement TMD.…”

“…Currently, the ultimate goal of TMD manegement is to reduce or eliminate pain, to improve jaw function, and to enhance the quality of life [2,3]. As generally agreed, conservative treatments should always be the rst choice for TMD, including health education, medication, rehabilitation therapy, occlusal splint therapy, and even arthroscopic surgery [4].…”