Administration of Low-level Laser on Muscles of Mastication Following the Induction of Initial Fatigue

University of Nove de Julho

Status: Unknown

Conditions: Muscle Fatigue

Treatments: Radiation: Sham laser; Radiation: Active laser; Diagnostic Test: Control group

Study type: Interventional

Funder types: Other

Identifiers

NCT03460639

919822905

290582 (Other Identifier)

Details and patient eligibility

About

Orofacial pain encompasses painful conditions, such as temporomandibular disorder. Multidisciplinary health teams seek to control such musculoskeletal disorders to improve the quality and functional capacity of the muscles of mastication. The aim of the proposed study is to evaluate the effect of low-level laser therapy as a form of treatment for the prevention of initial fatigue of the muscles of mastication (masseter and anterior temporal muscles) as well as the recovery of these muscles after induced exhaustion (caused by isometric contraction) in young adults. The participants will be 78 (n obtained from calculation of the sample size with p < 0.05) healthy male and female volunteers between 18 and 34 years of age. The volunteers will be randomly allocated to a laser group (n = 26), sham group (n = 26) and control group (n = 26). All participants will be submitted to a clinical evaluation to record mandibular movements, bite force, muscle sensitivity to palpation and initial muscle fatigue. Initial fatigue will be induced by isometric contraction of the jaws. Maximum voluntary contraction will be performed to record the time until initial exhaustion of the masseter muscle (determined by electromyography). The groups will then be submitted to the interventions: 1) active laser therapy (wavelength: 780 nm; fluence: 134 J/cm2; power: 50 mW; irradiance: 1.675 W/cm2; exposure time: 80 seconds per point) on three points of the masseter and one point on the anterior temporal muscles on each side, 2) sham laser (placebo effect) or 3) no intervention (control). Maximum voluntary contraction will be performed again after the interventions to record the time until initial exhaustion of the masseter muscle (determined by electromyography). Differences in individual time until exhaustion between the pre-intervention and post-intervention evaluations will be measured to determine the effect of low-level laser therapy.

Enrollment: 78 estimated patients

Sex: All

Ages: 18 to 34 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• will be included in this study young people in the age range between 18-34 years, without diagnosis of temporomandibular disorder (TMD) and with the signed free informed consent term.

Exclusion criteria

• will be excluded from the study individuals who are in orthodontic or orthopedic treatment of the jaw, psychological and / or physiotherapy. Also excluded are those who are taking anti-inflammatory drugs and anti-inflammatory drugs and occlusal plaques.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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78 participants in 3 patient groups

Active laser

Active Comparator group

Description:

Three points on the masseter muscle (upper, middle and lower portions) and one point on the anterior temporal on each side of the face will be irradiated with a wavelength of 780 nm, radiant exposure of 134 J/cm2, power of 50 mW and irradiance of 1.675 W/cm2 for 80 seconds per point, resulting in an energy of 4 J per point and total energy of 32 J per volunteer.20,21 Point application will be performed with a conventional tip in contact with the skin (beam spot: 0.04 cm2).

Treatment:

Radiation: Active laser

Sham laser

Sham Comparator group

Description:

The same procedures will be performed in the sham group, but the device will be switched off and a recording of the emission sounds will be used to give the volunteer the auditory sensation of laser therapy.

Treatment:

Radiation: Sham laser

Control group

Other group

Description:

In this group, no treatment will be done, we will only induce fatigue, for evaluation.

Treatment:

Diagnostic Test: Control group