Investigating pain inhibition in chronic jaw pain conditions

The Role of Endogenous Pain Inhibition Deficiency in Chronic TMD Pain Pathophysiology

This study is trying to see how well people with chronic jaw pain can manage pain compared to those without pain, using a special test to understand how different types of pain affect them.

Quick facts

• Study type: Observational
• Enrollment: 40 (estimated)
• Ages: 18 Years to 74 Years
• Sex: All
• Sponsor: University of Minnesota (Academic / other)
• Locations: 1 site (Minneapolis, Minnesota)
• Trial ID: NCT06617494 on ClinicalTrials.gov

What this trial studies

This observational study aims to explore the efficiency of endogenous pain inhibition in individuals suffering from chronic temporomandibular disorders (TMD) compared to healthy controls. By utilizing the conditioned pain modulation (CPM) test, the study will assess how different stimuli affect pain inhibition in the face and other areas. Participants will include both individuals with chronic TMD pain and matched pain-free controls, with a focus on understanding the relationship between pain inhibition and fluctuations in TMD pain intensity. The findings could provide insights into the mechanisms underlying chronic pain in TMD patients.

Who should consider this trial

Good fit: Ideal candidates include individuals aged 18 to 74 with chronic TMD pain or healthy volunteers without significant orofacial pain.

Not a fit: Patients with significant orofacial pain or a previous diagnosis of common pain-related TMD conditions may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved understanding and management of chronic TMD pain.

How similar studies have performed: While the study addresses a known issue in TMD pain management, the specific approach of assessing endogenous pain inhibition through CPM testing is relatively novel.

Eligibility criteria

Inclusion Criteria:

To be eligible to participate in this study, an individual must meet all the following criteria:

1. Provide informed consent, documented in a signed and dated form.
2. Will comply with all study procedures, including daily ratings filling before and after the in-person study visit, and be available for the study duration.
3. All participants of both genders between ages 18 to 74 years.
4. Cases and controls will be matched for age within ±5 years, and all participants must understand English commands to follow study procedures (e.g., during CPM testing).

Pain-free controls:

1. Age matching (within ±5 years)
2. No previous diagnosis for the most common pain-related TMD as defined in the DC/TMD criteria (myalgia, arthralgia, headache attributed to TMD)
3. No significant orofacial pain (jaw pain, TMJ pain) in the past 3 months (""significant"" meaning 5 or more days in any month or any pain during the past month)
4. No report of significant pain in the last 3 months elsewhere in the body (""significant"" meaning 5 or more days in any month or any pain during the past month), e.g., low back pain, fibromyalgia, migraine headaches
5. Not meeting any of the most common pain-related TMD diagnoses as described in the DC/TMD criteria (myalgia, arthralgia, headache attributed to TMD) upon clinical exam following the DC/TMD protocol

Chronic painful TMD cases:

1. Primary TMD case criteria: Myalgia (masticatory muscle pain) based on clinical exam following the DC/TMD protocol
2. Concurrent arthralgia (TMJ pain) and/or headache attributed to TMD allowed
3. Myofascial pain must meet the following criteria:

   1. Onset \>3 months, occurring \>15 days/month on average for \>3 months
   2. Minimum of 10 jaw pain episodes since onset, each lasting at least 30 minutes and no less than 2 hours within the day, OR unremitting."

Exclusion Criteria:

An individual who meets any of the following criteria will be excluded from participation in this study:

1. Traumatic facial injury or surgery on the face/jaw, arms, or hands
2. Presence of pain related to dental and periodontal pathology
3. Pregnant
4. Has any of the following medical conditions by self-report:

   1. Renal failure or dialysis
   2. Heart disease (examples: uncontrolled arrhythmia or hypertension, cardiomyopathy) or heart failure
   3. Non-allergic bronchospasm (chronic obstructive pulmonary disease and emphysema)
   4. Diabetes (type I or II) that is not controlled with medication or diet
   5. Hyperthyroidism
   6. Uncontrolled seizures
5. Used any injection therapy (e.g., tender or trigger point injections, steroid injections), acupuncture, biofeedback, or TENS for managing facial/jaw pain within 2 weeks before the screening assessment.
6. If undergoing botulinum toxin injections in the head and neck area, must be 3 months since the last set of injections, and refrain from this treatment until study participation has ended
7. History of major depression or other major psychiatric disorder requiring inpatient hospitalization within the last 6 months before the screening assessment
8. History of treatment for drug or alcohol abuse within the last 12 months
9. Current pain medication use (e.g., opioids, ibuprofen, acetaminophen) that cannot be stopped \<24 hours before each study visit
10. Other conditions/diseases associated with altered pain perception: neurological or development disorders (dementia, autism spectrum disorder), neoplasm, multiple sclerosis, trigeminal neuralgia
11. Adults lacking the capacity to provide informed consent for themselves
12. Unable to understand instructions for sensory testing in English.
13. Thermal threshold for Pain-50 (pre-determined at the beginning of visit 1) is outside the temperature range of 40ºC to 49ºC
14. Inability to complete at least four daily ratings between the Informed consent, Pre-visit 1 procedures, and in-person visit 1
15. Lack of access to electronic devices with internet connection during the study participation
16. Anything that would place the individual at increased risk or preclude the individual's full compliance with study procedures or completion of the study. "

Where this trial is running

Minneapolis, Minnesota

• University of Minnesota — Minneapolis, Minnesota, United States (Recruiting)

Study contacts

• Principal investigator: Estephan Moana-Filho — University of Minnesota
• Study coordinator: Carla Campbell

Conditions Chronic Temporomandibular Disorders; Temporomandibular disorders; Chronic pain; Healthy volunteers