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Bottom line
Central sensitization appears to play a role in TMD pain and its overlap with fibromyalgia and headaches; a range of conservative and pharmacological treatments may help reduce this component, but the evidence base is limited and not yet conclusive.
Preliminary evidencePublished
Evidence hierarchy
Study participants
Patients with temporomandibular disorders, with emphasis on myogenous (muscle-related) TMD pain and its overlap with fibromyalgia and primary headaches
Study Summary
This comprehensive (narrative) review examines the role of central sensitization in temporomandibular disorders (TMD), focusing on how myogenous TMD can overlap with other chronic primary pain conditions such as fibromyalgia and primary headaches through dysfunction of the central nervous system. The authors review how central sensitization is diagnosed (pressure algometry/pressure pain thresholds, quantitative sensory testing, and screening tools like the Central Sensitization Inventory) and survey the evidence for pharmacological and conservative/rehabilitative treatments. They report that several first-line conservative approaches and medications may have a positive impact on the central sensitization component of TMD pain, but conclude there is still no agreement in the literature and that the evidence base remains limited. The authors emphasize multimodal management and call for further observational research.
Key Findings
| Finding | Detail | Impact |
|---|---|---|
| Myogenous TMD overlaps with fibromyalgia and primary headaches via central sensitization | Unlike arthrogenous (joint) TMD, which appears localized, muscle-related (myogenous) TMD may share features with other chronic primary pain conditions such as fibromyalgia, migraine, and tension-type headache, all linked to CNS dysfunction and central sensitization (hyperexcitability of dorsal horn neurons, with hypersensitivity, allodynia, and pressure hyperalgesia). | High |
| Pressure pain thresholds are lowered in TMD patients in pooled evidence | Citing a 2018 systematic review/meta-analysis (La Touche et al., 22 studies), 8 of 12 studies evaluating pressure pain threshold (PPT) found PPT significantly lower in TMD patients vs controls, with strong evidence for greater trigeminal pressure pain sensitivity; thermal (hot/cold) pain thresholds showed no significant group differences. A 2021 meta-analysis (Meng et al.) in muscle-pain-related TMD also found reduced PPT and mechanical pain thresholds. | High |
| Conservative and pharmacological therapies may positively affect central sensitization, but evidence is unsettled | First-line treatments reviewed include physical therapy, occlusal splints, low-level laser therapy (LLLT), extracorporeal shockwave therapy (ESWT), TENS, oxygen-ozone therapy, biofeedback, and drugs (NSAIDs, beta-blockers, antidepressants, antiseizure medications, opioids). The authors state these may have a positive impact on central sensitization of TMD pain but that there is still no agreement in the literature. | Medium |
| Drug evidence for TMD pain is limited; specific agents show some benefit | A cited Cochrane review of TMD medications (11 studies) found insufficient evidence to support or refute any drug. Reported positive trial results include naproxen 500 mg twice daily reducing TMD symptoms, propranolol 60 mg twice daily achieving facial-pain-index reductions (greater effect in migraineur TMD patients), low-dose amitriptyline (25 mg/day) reducing pain, and gabapentin reducing spontaneous TMJ pain and tender muscle sites; clonazepam did not significantly differ from placebo. | Medium |
| Central sensitization screening tools exist but are not TMD-validated | The Central Sensitization Inventory (CSI; part A 25 symptoms with a 40-point cut-off, part B 10 conditions), the Pain Sensitivity Questionnaire (PSQ, 17 items), and the Sensory Hypersensitivity Scale (SHS, 25 items) are described as screening tools; the authors note further study is needed to establish these specifically in TMD patients. | Medium |
Unlike arthrogenous (joint) TMD, which appears localized, muscle-related (myogenous) TMD may share features with other chronic primary pain conditions such as fibromyalgia, migraine, and tension-type headache, all linked to CNS dysfunction and central sensitization (hyperexcitability of dorsal horn neurons, with hypersensitivity, allodynia, and pressure hyperalgesia).
Citing a 2018 systematic review/meta-analysis (La Touche et al., 22 studies), 8 of 12 studies evaluating pressure pain threshold (PPT) found PPT significantly lower in TMD patients vs controls, with strong evidence for greater trigeminal pressure pain sensitivity; thermal (hot/cold) pain thresholds showed no significant group differences. A 2021 meta-analysis (Meng et al.) in muscle-pain-related TMD also found reduced PPT and mechanical pain thresholds.
First-line treatments reviewed include physical therapy, occlusal splints, low-level laser therapy (LLLT), extracorporeal shockwave therapy (ESWT), TENS, oxygen-ozone therapy, biofeedback, and drugs (NSAIDs, beta-blockers, antidepressants, antiseizure medications, opioids). The authors state these may have a positive impact on central sensitization of TMD pain but that there is still no agreement in the literature.
A cited Cochrane review of TMD medications (11 studies) found insufficient evidence to support or refute any drug. Reported positive trial results include naproxen 500 mg twice daily reducing TMD symptoms, propranolol 60 mg twice daily achieving facial-pain-index reductions (greater effect in migraineur TMD patients), low-dose amitriptyline (25 mg/day) reducing pain, and gabapentin reducing spontaneous TMJ pain and tender muscle sites; clonazepam did not significantly differ from placebo.
The Central Sensitization Inventory (CSI; part A 25 symptoms with a 40-point cut-off, part B 10 conditions), the Pain Sensitivity Questionnaire (PSQ, 17 items), and the Sensory Hypersensitivity Scale (SHS, 25 items) are described as screening tools; the authors note further study is needed to establish these specifically in TMD patients.
Strengths
- Described by the authors as the first comprehensive review to investigate both the diagnosis and the treatment of TMD through control of central sensitization.
- Broad coverage spanning mechanisms, diagnostic/assessment tools, pharmacological therapies, physical/rehabilitative modalities, and interventional therapies.
- Explicitly frames TMD within the chronic primary pain (ICD-11) and comorbidity context, including fibromyalgia and primary headaches.
- Consistently reports the limited and unsettled nature of the evidence rather than overstating benefits.
Limitations
- The authors acknowledge the lack of a systematic literature search and the absence of a meta-analysis.
- Heterogeneity of the underlying studies prevented quantitative analysis, and reliance on numerous observational studies with differing outcomes makes strong conclusions difficult.
- Central sensitization cannot be measured directly, complicating its assessment in TMD.
- Several cited treatment effects come from animal/preclinical models or small trials; randomized controlled trials for TMD pharmacotherapy are still lacking, and a Cochrane review found insufficient evidence to support or refute any drug.
- Screening tools such as the CSI, PSQ, and SHS are not yet validated specifically in TMD populations.
Key Takeaways for Patients
What This Means for You
- 01Jaw pain from temporomandibular disorders (TMD), especially muscle-related TMD, can be connected to how the nervous system processes pain (central sensitization) and may overlap with conditions like fibromyalgia and headaches/migraine.
- 02Doctors cannot measure central sensitization directly, but they can use tools such as pressure pain testing and questionnaires to assess how sensitive the nervous system has become.
- 03First-line care is usually conservative and non-invasive, including physical therapy, jaw exercises, posture work, occlusal splints (bite guards), laser, shockwave, TENS, and ozone therapy.
- 04Several medications (such as NSAIDs, certain antidepressants at low doses, beta-blockers, and some anti-seizure drugs) may help TMD pain, but strong evidence is limited and treatment is often tailored case by case.
- 05A multidisciplinary, multimodal approach is often most effective, and emotional factors like anxiety and depression can increase pain sensitivity and should be addressed.
Read the Full Paper
Access the complete peer-reviewed study from International Journal of Molecular Sciences
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