Effects of Photobiomodulation With Low-Level Laser Therapy in Burning Mouth Syndrome: A Randomized Clinical Trial

Study design A randomized, single blind, clinical trial was performed among patients with Burning Mouth Syndrome who attended the Oral Medicine Specialist Degree Program at the School of Dentistry at Complutense University in Madrid. This study was approved by the Hospital San Carlos Ethics Committee in Madrid (IEC no. 17/311-R_P) according with the principles of the Helsinki Declaration. This clinical study followed the guidelines established by the Consort Statement (http://www.consort-statement.org/).

Participants Adult patients older than 18 years of age who fulfilled the International Classification of Headache Disorders (ICHD-3) diagnostic criteria for BMS were consecutively included in this study. Patients not interested in participate in the study, unable to understand or answer the questionnaires and follow the appointments, patients suffering hiposialia or Sjögren's syndrome, patients who had received head and neck radiotherapy, pregnant women, patients with uncontrolled systemic diseases (diabetes, thyroid diseases, fibromyalgia or anemia) and patients suffering burning mouth symptoms secondary to local factors were excluded. Patients also had to read and sign and informed consent prior to inclusion in the study.

Before beginning the treatment, all patients provided a full medical history and a complete blood test including blood levels of iron, vitamin B12, folic acid, TSH and basal glucose levels. Patients who did not provide the blood tests, did not attend any of the appointments or follow-ups or did not fulfill correctly the questionnaires were removed from the study.

Interventions LLLT was applied in the study group with a Diode Laser Fox (A.R.C. Laser, Italy) using these parameters: a wavelength of 810 nm, a power of 0.6 W, a power density of 1.2 W/cm2, a beam area of 0.08 cm2 and an energy of 6 J with an application time per point of 10 seconds in 56 points (3 in the vestibular mucosa of the 4 quadrants, 6 in each of the two buccal mucosa, 6 in the hard palate, 4 in each lateral of the tongue, 6 in the dorse of the tongue and 4 sublingual points) with a distance between points of 2mm. It was applied, therefore, a dose of 12 J/cm2 in a continuous mode in a total of 10 sessions, 2 sessions per week for 5 weeks. The laser was applied perpendicularly in contact with the mucosa. All patients and the clinician wore the protective eyeglasses provided with the laser device.

For the placebo group the Low-Level Laser Therapy was applied in the same 56 points, 10 seconds per point and the same number of sessions but with the device turned off.