Endogenous Pain Inhibition Deficiency in Chronic TMD Pain
United States40 participantsStarted 2024-09-16
Plain-language summary
Temporomandibular disorders (TMDs) involve a range of conditions with varied causes, affecting a large portion of the U.S. population and posing challenges for diagnosis and management, especially in chronic cases. Despite advances in understanding TMD pathophysiology, the role of central sensitization, particularly deficient endogenous pain inhibition, remains unclear. The conditioned pain modulation (CPM) test, used to assess pain inhibition in chronic TMD pain, has produced inconsistent results due to varying testing parameters. The proposed cross-sectional study will investigate the efficiency of endogenous pain inhibition in individuals with chronic TMD pain compared to controls by applying noxious and non-noxious stimuli to facial and non-facial sites. The findings aim to clarify the impact of weaker pain inhibition over the face, how the conditioning stimulus' painfulness affects inhibition and the relationship between pain inhibition and fluctuations in TMD pain intensity.
Who can participate
Age range
18 Years – 74 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Provide informed consent, documented in a signed and dated form.
. 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.
. All participants of both genders between ages 18 to 74 years.
. 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).
. Age matching (within ±5 years)
. No previous diagnosis for the most common pain-related TMD as defined in the DC/TMD criteria (myalgia, arthralgia, headache attributed to TMD)
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Conditioned pain modulation (CPM) effect
Timeframe: 3.5 hours single in-person visit
2
The relationship between daily pain intensity fluctuation and endogenous pain modulation (EPM) efficiency
Timeframe: 14 days: 7 days before and 7 days after the in-person visit
. 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)
. 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
Exclusion criteria
. Traumatic facial injury or surgery on the face/jaw, arms, or hands
. Presence of pain related to dental and periodontal pathology
. Pregnant
. Has any of the following medical conditions by self-report:
. Renal failure or dialysis
. Heart disease (examples: uncontrolled arrhythmia or hypertension, cardiomyopathy) or heart failure
. Non-allergic bronchospasm (chronic obstructive pulmonary disease and emphysema)
. Diabetes (type I or II) that is not controlled with medication or diet