If you read our September 10 post about ULLTRA, the trial testing light therapy for jaw pain, you have already met some of Margarete Ribeiro-Dasilva’s work without meeting her. She is its principal investigator.
She is a Clinical Professor in the Division of Prosthodontics at the UF College of Dentistry, and she does something this week’s theme is actually about: she runs a clinic, a laboratory and a clinical trial, and treats them as one activity rather than three.
In the clinic, she sees patients with denture problems, toothaches, and temporomandibular disorders — TMD, the family of conditions affecting the jaw joint and the muscles that move it. TMD is worth pausing on. It can mean constant facial pain, difficulty eating, disrupted sleep and headaches that never fully lift, it falls disproportionately on women, and it is routinely dismissed.
In the laboratory, she has spent two decades asking why. Her answers keep landing on the interaction between hormones, immune response and genetics.
A 2009 study in The Journal of Pain, comparing 200 women with TMJ disorder against 100 controls, found a specific estrogen receptor-alpha gene variant markedly more common in the women with painful TMJ disorder. A 2017 study in the Journal of Dental Research went after the mechanism: women with TMD showed a hyperinflammatory immune response, their monocytes releasing more IL-6 after a challenge, with estrogen amplifying the effect — and the women reporting more pain produced more IL-6.
She was also part of the large OPPERA genetics team whose 2019 paper in PAIN reported a variant near the MRAS gene associated with painful TMD in men only. Read alongside her own work, the picture is not “TMD is a women’s condition” but something more interesting: the routes into it may differ by sex.
In the trial, she is testing whether any of this can be turned into treatment. ULLTRA (NCT05916235) is a randomized, double-blind, sham-controlled trial of photobiomodulation — low-level light therapy — for TMD pain, funded by a five-year NIDCR grant, with Roger Fillingim as co-principal investigator. It is registered as NCT05916235 and currently listed as recruiting; the full record — design, eligibility, outcomes and contacts — is public on ClinicalTrials.gov.
And the laboratory work has followed the trial back indoors. A 2025 paper in the Journal of Oral & Facial Pain and Headache, on which she is senior author, took immune cells from people with painful TMD and applied the same light protocol in a dish. The cells shifted away from an inflammatory profile toward a repair-oriented one — a plausible mechanism for why the treatment might work, being investigated in parallel with whether it does.
That loop — chair to bench to trial and back — is what a pain center is for.
We asked her what she wishes patients with jaw pain were told sooner.
I wish patients with jaw pain were told to seek care when the first signs that something is wrong appear rather than trying to live with it. The longer pain persists, the more difficult it can become to treat, so early attention really matters.
Margarete C. Ribeiro-Dasilva, DDS, MS, PhD
What we study:
- Pain and Aging
- Chronic Pain Risk Factors
- Pain and the Brain
- Musculoskeletal Pain
- Pain and Exercise
- Non-Medical Treatment of Pain
Prefer to talk to a person? Call 352-273-5967 or email PRICE-CTSI@ufl.edu.
UF Study ID IRB201400126
References
- Photobiomodulation for Management of Temporomandibular Disorder Pain (ULLTRA). Principal Investigator: Margarete C. Ribeiro-Dasilva, DDS, MS, PhD. ClinicalTrials.gov Identifier NCT05916235. Status: Recruiting. https://clinicaltrials.gov/study/NCT05916235
- Rodriguez MG, Warchol M, Rubio S, et al., Migliorati CA, Gibson FC 3rd, Ohrbach R, Fillingim RB, Wallet S, Ribeiro-Dasilva MC. In vitro effects of dual wavelength photobiomodulation on monocytic response in painful temporomandibular disorder. J Oral Facial Pain Headache. 2025 Dec;39(4). https://doi.org/10.22514/jofph.2025.082
- Ribeiro-Dasilva MC, Fillingim RB, Wallet SM. Estrogen-Induced Monocytic Response Correlates with Temporomandibular Disorder Pain: A Case Control Study. J Dent Res. 2017 Mar;96(3):285-291. https://doi.org/10.1177/0022034516678599
- Smith SB, Parisien M, Bair E, et al., Ribeiro-Dasilva MC, Fillingim RB, Greenspan JD, Ohrbach R, Slade GD, Maixner W, Diatchenko L. Genome-wide association reveals contribution of MRAS to painful temporomandibular disorder in males. Pain. 2019 Mar;160(3):579-591. https://doi.org/10.1097/j.pain.0000000000001438
- Ribeiro-Dasilva MC, Peres Line SR, Leme Godoy dos Santos MC, Arthuri MT, Hou W, Fillingim RB, Rizzatti Barbosa CM. Estrogen receptor-alpha polymorphisms and predisposition to TMJ disorder. J Pain. 2009 May;10(5):527-533. https://doi.org/10.1016/j.jpain.2008.11.012