Electromyography evaluation of occlusal splint influence on orbicularis oris in denture-wearing subjects with temporomandibular dysfunction and orofacial pain

  • Almenara de Souza Fonseca-Silva
  • Eduardo Sillos Uchoa
  • Mauro Antonio de Arruda Nóbilo
  • Fausto Bérzin
Keywords: occlusal splint, orofacial pain, electromyography


The occlusal splint constitutes a resource frequently used on temporomandibular dysfunction (TMD) and orofacial pain treatment, including the denture-wearing patients. Considering the active participation of lips in the functions of the stomatognathic system, the aim of this study was to verify the influence of occlusal splints on electromyography activity (EMG) of two portions – upper (OBU) and lower (OBL) of orbicularis oris muscle, during the yogurt suction. EMG was accomplished before and 70 days after the use of these splints, in 8 edentulous denture-wearing patients and that had signs and symptoms of TMD. The myoeletric signs were recorded by a electromyography (*Lynx Eletronics) with Butterworthtype band pass filter (20-500 Hz) with gain of 100 times and A/D converter board. The signs were caught by Ag/AgCl surface electrodes (Medi Trace) and displayed through by Aqdados Software installed in an Ibm-pc 486 DX2. The EMG sign was processed by Matlab® Software and the averages of the non-normalized amplitude envoltories (NNA) were statistically analyzed using Mann-Whitney test (p < 0,05). The NNA values found on pre-treatment was 60,11 ± 4.28 and 86,15 ± 6.15 μV and in the post-treatment was 106,0 ± 4.80 and 103,71 ± 3.83 μV for the portions OBU and OBL respectively. The verified statistical difference was highly significant (p < 0,0001) when compared the same muscular portion before and after use of splints. The results of this study, on those experimental conditions used, may conclude that the use of occlusal splints promoted a significant increase of the electric activity of the orbicularis oris. UNITERMS: occlusal splint; orofacial pain; electromyography.

Author Biographies

Almenara de Souza Fonseca-Silva
Doutora em Clínica Odontológica – Área de Prótese Dental pela FOP/UNICAMP.
Eduardo Sillos Uchoa
Cirurgião-dentista em Campinas/SP.
Mauro Antonio de Arruda Nóbilo
Professor Associado do Departamento de Prótese e Periodontia da FOP/UNICAMP.
Fausto Bérzin
Professor Titular do Departamento de Morfologia da FOP/UNICAMP.
Original Article