Bruxism, Myofascial Pain
Conditions
Keywords
Botulinum Toxin Type A, Botulinum Neurotoxin Type A, Bruxism, Jaw Muscle Pain, Myofascial Pain, Oral Ibuprofen, Nonsteroidal Anti-inflammatory Drugs, Visual Analogue Scale, OHIP-14, Oral Health-Related Quality of Life, Randomized Controlled Trial, Masseter Muscle, Temporalis Muscle
Brief summary
This randomized controlled trial evaluated the effectiveness of Botulinum Toxin Type A compared with oral ibuprofen in reducing pain and improving oral health-related quality of life in patients with sleep bruxism and jaw muscle pain. Forty participants diagnosed with sleep bruxism were randomly assigned to receive either Botulinum Toxin Type A injections into the masseter and temporalis muscles or oral ibuprofen therapy. Participants were followed for 20 weeks. The primary outcome was pain intensity measured using the Visual Analogue Scale (VAS). Secondary outcomes included oral health-related quality of life assessed using the Oral Health Impact Profile-14 (OHIP-14), muscle tenderness, and mandibular function.
Detailed description
Bruxism is a parafunctional masticatory muscle activity characterized by repetitive clenching or grinding of the teeth and/or bracing or thrusting of the mandible. It is commonly associated with jaw muscle pain, muscle tenderness, fatigue, restricted mandibular movement, and impairment of oral health-related quality of life. Conventional treatment strategies include behavioral interventions, occlusal splints, physical therapy, and pharmacological agents such as non-steroidal anti-inflammatory drugs (NSAIDs). However, these approaches may not provide adequate symptom control in all patients, particularly those with persistent muscular pain. Botulinum Toxin Type A has been increasingly investigated as an alternative therapeutic option because it produces temporary chemodenervation by inhibiting the presynaptic release of acetylcholine at the neuromuscular junction. This mechanism reduces excessive muscle contraction and may alleviate pain, decrease muscle tenderness, and improve mandibular function. Despite encouraging evidence from previous studies, further randomized controlled trials comparing Botulinum Toxin Type A with conventional pharmacological therapy remain necessary to establish its clinical effectiveness. The present study was designed as a prospective, randomized, controlled clinical trial conducted at the Department of Dentistry, New Cyprus Health and Social Sciences University. Forty adult patients diagnosed with sleep bruxism associated with jaw muscle pain were enrolled after meeting the predefined eligibility criteria and providing written informed consent. Participants were randomly allocated into two equal treatment groups. The intervention group received Botulinum Toxin Type A injections administered into the bilateral masseter and temporalis muscles according to the study protocol, whereas the control group received oral ibuprofen therapy. Clinical assessments were performed at baseline and during a 20-week follow-up period. Pain intensity was evaluated using the Visual Analogue Scale (VAS), while oral health-related quality of life was assessed using the Oral Health Impact Profile-14 (OHIP-14). Additional clinical outcomes included muscle tenderness on palpation and mandibular function. Safety assessments were conducted throughout the study by monitoring treatment-related adverse events and documenting any unexpected clinical findings. The primary objective of this trial was to compare the effectiveness of Botulinum Toxin Type A with oral ibuprofen in reducing pain intensity in patients with sleep bruxism. Secondary objectives included evaluating changes in oral health-related quality of life, muscle tenderness, mandibular function, and the overall clinical response following treatment. The findings of this study are intended to provide evidence regarding the comparative effectiveness of Botulinum Toxin Type A as a minimally invasive treatment option for patients experiencing jaw muscle pain related to sleep bruxism.
Interventions
Botulinum Toxin Type A was administered by intramuscular injection into the bilateral masseter and temporalis muscles according to the study protocol. The intervention was performed once at baseline, and participants were followed for 20 weeks to evaluate pain intensity, oral health-related quality of life, muscle tenderness, and mandibular function.
DRUGIbuprofen
Ibuprofen was administered orally at a dose of 600 mg three times daily for one week according to the study protocol. Participants were followed for 20 weeks to evaluate pain intensity, oral health-related quality of life, muscle tenderness, and mandibular function.
Sponsors
NEW Cyprus Health and Social Sciences University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Masking description
Due to the nature of the interventions (Botulinum Toxin Type A injections versus oral ibuprofen therapy), blinding of participants and the treating investigator was not feasible. Outcome assessment was based on standardized patient-reported outcome measures (VAS and OHIP-14), and statistical analyses were performed using coded data to minimize analytical bias.
Intervention model description
Participants were randomly assigned in a 1:1 ratio to one of two parallel treatment groups. The intervention group received Botulinum Toxin Type A injections into the bilateral masseter and temporalis muscles, while the control group received oral ibuprofen. Participants remained in their assigned treatment group throughout the 20-week follow-up period, and no crossover between treatment groups occurred.
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* Adults aged 18 years or older. * Clinical diagnosis of sleep bruxism. * Presence of jaw muscle pain. * Ability to provide written informed consent.
Exclusion criteria
* Pregnancy or breastfeeding. * Previous botulinum toxin treatment within 6 months. * Neuromuscular disorders. * Allergy to botulinum toxin or ibuprofen. * Use of medications affecting neuromuscular function.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Pain Intensity Measured by the Visual Analogue Scale (VAS) | Baseline to Week 20 (week 1, week 2, week 4, week 8, week 12, week 16, and week 20). | Pain intensity will be assessed using the 10-point Visual Analogue Scale (VAS). Participants will mark their pain level on a horizontal line ranging from 0 (no pain) to 10 (worst pain imaginable). Pain severity may be interpreted as mild (1-3), moderate (4-6), or severe (7-9). The outcome measure will be the mean change in VAS score from baseline to each follow-up assessment. Lower scores indicate reduced pain intensity and improved treatment outcome. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Oral Health-Related Quality of Life (OHIP-14) | Baseline to Week 20 (week 1, week 2, week 4, week 8, week 12, week 16, and week 20). | Oral health-related quality of life will be assessed using the Oral Health Impact Profile-14 (OHIP-14), a validated questionnaire consisting of 14 items that evaluate the impact of oral conditions on functional limitation, physical pain, psychological discomfort, physical disability, psychological disability, social disability, and handicap. Each item is scored on a 5-point Likert scale (0 = Never, 1 = Hardly ever, 2 = Occasionally, 3 = Fairly often, and 4 = Very often), resulting in a total score ranging from 0 to 56. Higher total scores indicate poorer oral health-related quality of life, whereas lower scores indicate better quality of life. The outcome measure will be the mean change in the total OHIP-14 score from baseline to each follow-up assessment. |
| Change in Jaw Muscle Tenderness Assessed by Standardized Clinical Palpation | Baseline to Week 20 (week 1, week 2, week 4, week 8, week 12, week 16, and week 20). | Jaw muscle tenderness will be assessed by standardized bilateral manual palpation of the masseter and temporalis muscles using a consistent clinical examination protocol at every follow-up visit. The same trained, blinded outcome assessor will perform all examinations throughout the study to minimize inter-examiner variability. Tenderness will be evaluated by applying gentle, standardized digital pressure over predetermined anatomical sites of each muscle and recording the participant's pain response. The outcome measure will be the change in muscle tenderness from baseline to each scheduled follow-up visit, with reduced tenderness indicating clinical improvement following treatment. |
| Change in Mandibular Functional Performance Assessed by Clinical Examination | Baseline to Week 20 (week 1, week 2, week 4, week 8, week 12, week 16, and week 20). | Mandibular function will be evaluated using a standardized clinical functional examination performed by the same blinded outcome assessor at each follow-up visit. The assessment will include evaluation of maximum mouth opening, mandibular movements (opening, lateral excursion, and protrusion), functional jaw performance during routine clinical examination, and the presence of movement-related discomfort or functional limitation. The outcome measure will be the overall change in mandibular functional performance from baseline to each scheduled follow-up visit, with improved mandibular function indicating a better therapeutic response. |
Countries
Cyprus
Outcome results
None listed