Modified use of a dynamic bite opener--treatment and prevention of trismus in a child with head and neck cancer: a case report.

Trismus may be a complication arising during or after treatment of patients with head and neck cancer. Treatment of trismus is difficult, making prevention very important. To prevent and treat trismus in a patient with a nasopharyngeal tumor, the Contract-Relax-Antagonist-Contract (CRAC) technique was applied, with the aid of a custom-made dynamic bite opener (DBO). The CRAC technique in combination with the DBO, as a therapy/prevention program for trismus, is not referred to in the literature. The combination of CRAC and DBO appeared to be a gentle and effective method well tolerated by the patient.