Investigation of the Effectiveness of Occlusal Splint, Acupuncture, and Pharmacological Treatment in Myofascial Pain
Çifter et al. · J Tradit Complem Med · 2018
Evidence Level
MODERATEOBJECTIVE
To compare the effectiveness of nighttime occlusal splints, acupuncture, and acetaminophen in the treatment of myofascial pain
WHO
45 patients with myofascial pain syndrome diagnosed by Research Diagnostic Criteria for TMD
DURATION
3 months for occlusal splint, 5 sessions for acupuncture, 1 week for acetaminophen
POINTS
ST-6, ST-7, ST-8, GB-3, SI-18, LI-4 for acupuncture
🔬 Study Design
Occlusal splint
n=15
Hard 3 mm splint worn at night for 3 months
Acupuncture
n=15
5 acupuncture sessions at specific points
Acetaminophen
n=15
1,000 mg/day for 1 week in divided doses
📊 Results in numbers
Improvement in maximum mouth opening (splint)
Improvement in maximum mouth opening (acupuncture)
Reduction on VAS scale (all groups)
Improvement in pressure pain threshold
Percentage highlights
📊 Outcome Comparison
Maximum mouth opening (pre vs post)
Pain reduction (VAS)
This study compared three treatments for muscle pain in the face and jaw: a dental appliance worn at night, acupuncture sessions, and acetaminophen medication. The results show that both the dental appliance and acupuncture were effective in improving mouth opening and reducing pain, and were superior to acetaminophen in some respects.
Article summary
Plain-language narrative summary
This randomized study investigated the effectiveness of three distinct therapeutic approaches for the treatment of myofascial pain syndrome related to temporomandibular disorders: nighttime occlusal splints, acupuncture, and pharmacological treatment with acetaminophen. The research was conducted with 45 patients diagnosed according to the Research Diagnostic Criteria for Temporomandibular Disorders, randomized into three groups of 15 participants each. The first group used hard 3 mm occlusal splints at night for three months. The second group received five acupuncture sessions at points ST-6, ST-7, ST-8, GB-3, SI-18, and LI-4, with 30-minute sessions performed every 3-4 days.
The third group was treated with acetaminophen 1,000 mg/day divided into two equal doses for one week. Assessments included measurements of unassisted maximum mouth opening, pain scores on the Visual Analog Scale (VAS), and pressure pain thresholds in the temporalis, masseter, sternocleidomastoid muscles, and temporomandibular joint, using an algometer. The results demonstrated that both the occlusal splint and acupuncture produced significant increases in maximum mouth opening (from 44.80±5.83 to 48.33±6.53 mm in the splint group; from 41.07±6.44 to 44.60±5.92 mm in the acupuncture group), while acetaminophen showed no significant improvement in this parameter. All three treatments resulted in significant reductions in VAS pain scores.
In the assessment of pressure pain thresholds, the occlusal splint showed superior effectiveness to acetaminophen in five of the ten regions evaluated, while acupuncture surpassed acetaminophen in one region. No statistically significant differences were found between occlusal splint and acupuncture in most of the parameters evaluated. The study suggests that non-pharmacological approaches, particularly occlusal splints and acupuncture, may offer benefits superior to treatment with simple analgesics for this condition. The proposed mechanisms of action include modification of occlusal relationships and condylar positioning by splints, and stimulation of A-delta and C nerve fibers by acupuncture, leading to release of vasoactive neuropeptides.
The clinical implications suggest that a personalized approach, considering the individual patient profile, may be necessary to optimize therapeutic results in myofascial pain syndrome.
Strengths
- 1Randomized design comparing three therapeutic modalities
- 2Use of standardized diagnostic criteria (RDC/TMD)
- 3Objective evaluation with algometry for pain thresholds
- 4Active control group with standard medication
Limitations
- 1Small sample size (n=15 per group)
- 2Different treatment durations between groups
- 3Absence of placebo group
- 4Possible bias due to the unblinded nature of the treatments
Expert Commentary
Dr. Marcus Yu Bin Pai
MD, PhD · Pain Medicine · Physical Medicine and Rehabilitation · Medical Acupuncture
▸ Clinical Relevance
Chronic myofascial pain associated with temporomandibular disorders represents one of the most challenging conditions at the interface between physiatry, dentistry, and pain medicine — and frequently reaches the medical office only after going through multiple specialists without resolution. This randomized trial by Çifter et al. places three commonly used approaches side by side, with results that guide therapeutic choice in concrete scenarios: the patient who does not tolerate or refuses medication, the one who already uses a splint without complete response, or the one seeking a short-term strategy for functional control. The most directly applicable finding is the objective improvement in maximum mouth opening with both splint and acupuncture, while acetaminophen alone did not sustain this functional gain — which reinforces the rationale for reserving the simple analgesic as an adjuvant rather than the cornerstone of treatment in this population.
▸ Notable Findings
The most noteworthy point is that five acupuncture sessions, applied at points ST-6, ST-7, ST-8, GB-3, SI-18, and LI-4 at three-to-four-day intervals, produced gains in mouth opening comparable to the occlusal splint used for three months — without statistically significant differences between the two groups in most parameters. This suggests that acupuncture acts on a much shorter time horizon for measurable functional outcomes. Another striking finding is the algometric assessment of pressure pain thresholds in ten distinct regions, including temporalis, masseter, sternocleidomastoid, and TMJ: the splint surpassed acetaminophen in five of these regions, while acupuncture surpassed it in one — showing that the mechanisms of action of the two non-pharmacological approaches, although distinct, converge in overall clinical efficacy for this craniocervical myofascial pain phenotype.
▸ From My Experience
In my practice at the musculoskeletal pain clinic, temporomandibular myofascial pain frequently presents with associated cervical involvement — and the protocol of points used in this study, centered on the masticatory musculature, is very close to what I adopt, with the routine addition of dry needling at trigger points in the upper trapezius and splenius when there is cephalic radiation. I have observed perceptible functional response — less masticatory fatigue, improved opening — already in the first three sessions, which is consistent with the five-session course reported here. For maintenance, I usually propose cycles of six to eight sessions, progressively spaced. The profile that responds best, in my experience, is the patient without significant degenerative joint involvement of the TMJ and with predominantly muscular pain, identified clinically by algometry and the distribution of trigger points. I usually combine acupuncture with postural guidance and, when documented nighttime bruxism is present, the association with the splint makes sense — not as an alternative, but as a complementary strategy to expand and consolidate the functional gain.
Indexed scientific article
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Scientific Review
Marcus Yu Bin Pai, MD, PhD
CRM-SP: 158074 | RQE: 65523 · 65524 · 655241
PhD in Health Sciences, University of São Paulo. Board-certified in Pain Medicine, Physical Medicine and Rehabilitation, and Medical Acupuncture. Scientific review and curation of every entry in this library.
Learn more about the author →Medical disclaimer: This content is for educational purposes only and does not replace consultation, diagnosis, or treatment by a qualified professional. Some information may be assisted by artificial intelligence and is subject to inaccuracies. Always consult a physician.
Content reviewed by the medical team at CEIMEC — Integrated Centre for Chinese Medicine Studies, a reference in Medical Acupuncture for over 30 years.
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