A double-blind clinical trial was conducted on 30 female
Temporomandibular Disorders (TMD) patients who had
pain as a chief complaint. The patients were randomly allocated into three groups based on Low Intensity
Laser (LILT) regimes namely 820 nm
Gallium Aluminium Arsenide (
GaAlAs) laser at energy densities of 21.4J/cm(2), 107 J/cm(2) and placebo
laser. Each patient had three LILT treatments in a week. The pressure pain threshold (PPT) of trigger points in masticatory muscles, unassisted maximum mouth opening without
pain (MOSP) and symptom severity index (SSI) were recorded as baseline data and monitored after every treatment. Jaw kinesiology, electromyography (EMG) and
pain rating index from McGill
pain questionnaire were also recorded as baseline and final results. The analysis of covariance and further analysis showed that the higher energy density
laser group had significant increases in PPT and EMG amplitude recorded from voluntary clenching (cEMG) compared with the placebo group at P values 0.0001 and 0.022 respectively. A significantly greater number of patients recovered from myofascial
pain and TMJ
arthralgia as assessed clinically in the higher energy group compared with the placebo (P value = 0.02 and 0.006 respectively). There was no statistically significant difference in the other parameters of assessment among the groups at a P value 0.05. At a period of 2 to 4 weeks review after LILT, there was an average 52% reduction of
pain as assessed by SSI.