Botulinum Toxin Therapy for Managing Sleep Bruxism: A Randomized and Placebo-Controlled Trial.

The purpose of this study is to evaluate the effects of botulinum toxin type A (BoNT-A) for managing sleep bruxism (SB) in a randomized, placebo-controlled trial. Thirty SB subjects were randomly assigned into two groups evenly. The placebo group received saline injections into each masseter muscle, and the treatment group received BoNT-A injections into each masseter muscle. Audio-video-polysomnographic recordings in the sleep laboratory were made before, at four weeks after, and at 12 weeks after injection. Sleep and SB parameters were scored according to the diagnostic and coding manual of American Academy of Sleep Medicine. The change of sleep and SB parameters were investigated using repeated measures analysis of variance (RM-ANOVA). Twenty-three subjects completed the study (placebo group 10, treatment group 13). None of the SB episode variables showed a significant time and group interaction (p > 0.05) except for electromyography (EMG) variables. The peak amplitude of EMG bursts during SB showed a significant time and group interaction (p = 0.001). The injection decreased the peak amplitude of EMG bursts during SB only in the treatment group for 12 weeks (p < 0.0001). A single BoNT-A injection cannot reduce the genesis of SB. However, it can be an effective management option for SB by reducing the intensity of the masseter muscle.

Sectioned images and 3D models of a cadaver head with reference to dermal filler injection.

The purpose of this study was to describe anatomical consideration with reference to dermal filler injection on sectioned images and three dimensional (3D) models using Visible Korean for medical education and clinical training purposes in the field of facial surgery. Serially sectioned images of the head were acquired from a cadaver. Anatomic structures related to dermal filler injection were 3D-reconstructed based on sectioned images, and additional structures were built on the basis of the established ones using a semi-automatic method. The anatomical 3D models were assembled and converted to a PDF file (66MB), which can be downloaded and used for free. In the PDF file, noticeable anatomical structures related with dermal filler injection can be identified on the 3D models as well as on the sectioned anatomical images. The 3D models in PDF were optimized and displayed in real time. These state-of-the-art sectioned images, outlined images, and 3D models will aid students and trainees to acquire a better understanding of the anatomy related to dermal filler injection, and will also improve medical understanding of patients and the general public. The 3D models in PDF files also can be used on dermal filler injection simulations.

Effects of botulinum toxin on jaw motor events during sleep in sleep bruxism patients: a polysomnographic evaluation.

STUDY OBJECTIVES: To investigate the effects of botulinum toxin type A (BoNT-A) injection on jaw motor episodes during sleep in patients with or without orofacial pain who did not respond to oral splint treatment. METHODS: Twenty subjects with a clinical diagnosis of SB completed this study. Ten subjects received bilateral BoNT-A injections (25 U per muscle) into the masseter muscles only (group A), and the other 10 received the injections into both the masseter and temporalis muscles (group B). Video-polysomnographic (vPSG) recordings were made before and at 4 weeks after injection. Rhythmic masticatory muscle activity (RMMA) and orofacial activity (OFA) were scored and analyzed for several parameters (e.g., frequency of episodes, bursts per episode, episode duration). The peak amplitude of electromyographic (EMG) activity in the two muscles was also measured. RESULTS: BoNT-A injection did not reduce the frequency, number of bursts, or duration for RMMA episodes in the two groups. The injection decreased the peak amplitude of EMG burst of RMMA episodes in the injected muscles (p < 0.001, repeated measure ANOVA) in both groups. At 4 weeks after injection, 9 subjects self-reported reduction of tooth grinding and 18 subjects self-reported reduction of morning jaw stiffness. CONCLUSIONS: A single BoNT-A injection is an effective strategy for controlling SB for at least a month. It reduces the intensity rather than the generation of the contraction in jaw-closing muscles. Future investigations on the efficacy and safety in larger samples over a longer follow-up period are needed before establishing management strategies for SB with BoNT-A. CITATION: Shim YJ; Lee MK; Kato T; Park HU; Heo K; Kim ST. Effects of botulinum toxin on jaw motor events during sleep in sleep bruxism patients: a polysomnographic evaluation.