Considering the auxiliary potential effect of photobiomodulation in controlling persistent CTT and TMD-related pain in patients who have been diagnosed with COVID-19, and are recovered from the viral infection, we intend to conduct a clinical trial comparing two modalities of therapeutic laser application: local application and transcutaneous application in the radial artery.

One of the main advantages of auxiliary techniques in pain control is the decrease of the use of drugs for analgesia, avoiding side effects and tolerance caused by them, and promoting an improvement in the individual's quality of life.

Orofacial pain and tensional cephalea were symptoms commonly reported in COVID-19 patients, even after recovery, and were considered chronic pain in these cases. The pain control, in these cases, is mostly accomplished with the use of analgesic and anti-inflammatory drugs. However, there are auxiliary treatments that can reduce the amount of pharmacological intake and improve the quality of life of compromised individuals, one of them is photobiomodulation. Using lasers for treatments to control inflammation and pain is successfully performed, but the parameters and the ways of application are not yet strongly established. The aim of this research is to evaluate the effect of the application of photobiomodulation with red and infrared lasers applied locally and systemically. For this purpose, individuals who have been diagnosed with COVID-19 and have had a tension headache and/or orofacial pain for more than 3 months will be selected by convenience. The participants will be divided into two different groups: G1- photobiomodulation with red and infrared laser with local application on the pain points (808 nm and 660 nm,100 mW, 6J per point) and G2 -photobiomodulation with red laser with transcutaneous application on the radial artery (660 nm, 100mW, 30 minutes). All participants will be treated for a period of 4 weeks, with 8 application sessions. The effects will be measured by means of blood lactate level, Brief Pain Inventory, Visual Analog Scale (VAS), and Cephalea Impact Test.

Inclusion Criteria:

• Individuals of both sexes, between the ages of 19 and 65, complaining of persistent orofacial pain or functional-type cephalea, for more than 3 months.
• Individuals diagnosed with COVID-19, confirmed by RT-PCR for SARS-CoV-2 already recovered, at least 30 days after infection.

Exclusion Criteria:

• Individuals with diagnoses of neuropathies and headaches other than tension-type headache
• Physical or intellectual incapacity to answer the survey questionnaires; illiterate; diabetics, pacemakers, and pregnant women.
• Individuals who report photosensitivity to laser.