Treatment of Radiation Induced Trismus with A Custom-Made Opening Device

Objective: A commonly observed sequela of radiation therapy for malignancy of the head and neck is trismus, with a loss of function that can reduce the overall quality of life. Radiation can cause an intense fibrosis within the masticatory muscles and transforming growth factor beta 1 (TGF β1) is involved in the treatment process. Intensity-modulated radiation therapy (IMRT) for nasopharyngeal carcinoma (NPC) provides better temporomandibular joint (TMJ) sparing and, thus, may reduce the incidence of radiation-induced trismus after radiotherapy. The objective of this report is to describe the use of a custom-made mouth opening device in treatment of radiation-induced trismus in a patient who had received IMRT by the reason of NPC.

Method: A 13 year old female patient  with NPC, had chemotherapy  and  radiotherapy 3 years ago, was referred to the Prosthodontic Department of Selcuk University of Dentistry for prosthetic rehabilitation . A clinical assessment of the patient showed that she had limited oral opening (7mm) and severe dental caries .The patient also had been suffered from acute pulpitis. Dental treatment can not be applied because of inadequate interdental distance. An acrylic custom-made  device was designed for the treatment. The device had upper and lower parts connected together with  two vertical screws in the right and left canine regions. The patient activated the screws daily to increase  the oral opening. 

Result: Interdental distance was improved from 7 mm to 19.50 mm after 4 months follow-up.

Conclusion: Patients may experience a marked restriction of jaw opening and overall mobility, which is of great concern and impaired the quality of life.This intraoral opening device is usefull to get  enough vertical opening for dental treatment.