The neuromuscular reaction to continuous dynamic jaw extension in cases with restricted mouth opening.

20 patients with severe trismus resulting from either trauma or infection have been treated using the method of "continuous dynamic jaw extension". The clinical results and the electromyographic tests show that almost complete rehabilitation of mandibular movement is possible. The treatment is most effective during the healing phase of the abscess and as an early treatment for the traumatised patient. Extension exercises should not be undertaken during the exudative phase of abscess formation. The reaction ability of the masticatory musculature obtained from the electromyographic investigations is defined in the "reactive myotonus-index". Thus the jaw extension appliance used is helpful both in the diagnosis and treatment of severe trismus.