Patients with diagnosis of temporomandibular disorder and that are not submitted to pre-fatigue low-level laser therapy

Patients with diagnosis of temporomandibular disorder and that are submitted to pre-fatigue low-level laser therapy

Patients without diagnosis of temporomandibular disorder and that are not submitted to pre-fatigue low-level laser therapy

Patients without diagnosis of temporomandibular disorder and that are submitted to pre-fatigue low-level laser therapy

Patients with diagnosis of temporomandibular disorder and that are submitted to placebo low-level laser treatment

Three points will be irradiated over the masseter muscle (upper, middle and lower bundles) and one point will be irradiated over the anterior temporal muscle of each side of the face in the groups submitted to pre-fatigue laser. The following parameters will be employed: wavelength: 780 nm; energy density: 25 J/cm2; output power: 50 mW; power density: 1.25 W/cm2; and exposure time: 20 seconds per points, resulting in a total energy of 1 J per point. The laser will be applied punctually with a conventional tip in contact with the skin considering an area of 0.04 cm2.

A digital dynamometer will be used for the determination of bite force. The measurements will be taken in the region of the 1st molars.

The individuals will be instructed to open their mouths as wide as possible and maximum active vertical mandibular movement (distance between maxillary and mandibular central incisors) will be recorded with the aid of digital calipers. The individuals will then be instructed to repeat the motion with pressure applied to the maxillary and mandibular teeth to obtain maximum passive vertical mandibular movement with the aid of the calipers. These measurements will be made before and after LLLT.

The visual analog scale will be used before and after treatment to record pain upon palpation of the masseter and anterior temporal muscles. This is a numerical scale ranging from 0 (absence of pain) to 10 (worst pain imaginable) points.