Effect of the use of stabilization splint on masticatory muscle activities in TMD patients with centric relation-maximum intercuspation discrepancy and absence of anterior/lateral guidance

Objective: To assess the masticatory muscle activities in patients with temporomandibular disorders (TMD) with centric relation (CR)-maximum intercuspation (MI) discrepancy and absence of anterior/lateral guidance by electromyography (EMG).Methods: Forty-six patients with TMD and 34 controls underwent clinical evaluations and EMG recordings at baseline. Twenty-three patients and 17 controls wore a stabilization splint. The remaining subjects were followed up without any intervention. After 3 months, the EMG recordings and clinical evaluations were repeated.Results: At baseline, the EMG values at rest and EMG value variations after movements in patients were higher than those in controls. After treatment, no difference was observed between EMG values of patients and controls.Conclusion: In the present study, patients with TMD had abnormal muscular activities. The stabilization splint is effective for functional recovery of the masticatory muscles, possibly by eliminating the CR-MI discrepancy and establishing anterior/lateral guidance.