Bruxism, Myofascial Pain, Masseter Muscle Hypertrophy
Conditions
Keywords
bruxism, Botulinum Toxin A, Masseter Muscle, Ultrasonography, Muscle Thickness, Fractal Analysis, Histogram Analysis
Brief summary
This prospective pilot study aimed to evaluate short-term clinical and ultrasonographic changes in the masseter muscle following botulinum toxin injection in patients with bruxism. Clinical assessments included pain evaluation using the Visual Analog Scale (VAS), while ultrasonographic evaluation included measurement of masseter muscle thickness and quantitative texture analysis using fractal dimension and histogram parameters. Measurements were performed at baseline, 14 days, and 90 days after treatment. The study aimed to assess both macroscopic and microstructural changes in the muscle tissue.
Detailed description
This study investigated the short-term effects of botulinum toxin injection on the masseter muscle in patients with bruxism using quantitative ultrasonographic methods. All participants received bilateral botulinum toxin injections into the masseter muscle using a standardized technique. Ultrasonographic examinations were performed using a high-frequency linear probe. Masseter muscle thickness was measured at a standardized anatomical location during maximal clenching. For quantitative texture analysis, a fixed-size region of interest (ROI) was placed in the central intramuscular portion of the masseter muscle while avoiding fascia, bone, and artifacts. Fractal analysis was performed using the box-counting method to assess structural complexity, while histogram analysis was used to evaluate grayscale pixel distribution reflecting echotexture characteristics. Clinical and ultrasonographic measurements were recorded at baseline, 14 days, and 90 days post-injection. The study aimed to determine whether botulinum toxin induces not only functional and morphological changes but also microstructural alterations in muscle tissue.
Interventions
Botulinum toxin A was injected bilaterally into the masseter muscle using a standardized injection protocol. Injections were administered at three points in the most prominent region of the muscle. Clinical and ultrasonographic evaluations were performed at baseline, 14 days, and 90 days after injection.
Sponsors
Kahramanmaras Sutcu Imam University
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Masking description
No masking was applied in this study. All participants received the same intervention, and both participants and investigators were aware of the treatment.
Intervention model description
Single-group, non-randomized interventional study in which all participants received bilateral botulinum toxin injections into the masseter muscle. Outcomes were assessed longitudinally at baseline, 14 days, and 90 days post-intervention. Each participant served as their own control.
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
No
Inclusion criteria
Adults aged 18-60 years Clinically diagnosed with bruxism Scheduled for botulinum toxin injection into the masseter muscle Willing to participate and provided written informed consent Completed all follow-up visits (baseline, Day 14, and Day 90)
Exclusion criteria
Previous botulinum toxin injection to the masseter muscle Presence of neuromuscular disorders affecting masticatory muscles History of temporomandibular joint surgery Pregnancy or breastfeeding Presence of trauma, infection, or mass in the masseter region Any condition that may interfere with ultrasonographic evaluation Failure to complete follow-up visits
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Masseter Muscle Thickness | Baseline, Day 14, Day 90 | Change in masseter muscle thickness measured in millimeters using ultrasonography at baseline, 14 days, and 90 days following botulinum toxin injection. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pain Intensity (VAS Score) | Baseline, Day 14, Day 90 | Change in pain intensity measured using the Visual Analog Scale (VAS) ranging from 0 (no pain) to 10 (worst imaginable pain) at baseline, 14 days, and 90 days after botulinum toxin injection. |
| Fractal Dimension of Masseter Muscle | Baseline, Day 14, Day 90 | Change in fractal dimension values derived from ultrasonographic images using region-of-interest (ROI)-based analysis to assess microstructural complexity at baseline, 14 days, and 90 days post-intervention. |
| Ultrasound Echotexture (Histogram Analysis) | Baseline, Day 14, Day 90 | Change in grayscale histogram parameters obtained from ultrasound images of the masseter muscle, reflecting echotexture characteristics, at baseline, 14 days, and 90 days after treatment. |
Countries
Turkey (Türkiye)
Outcome results
None listed